The Quest for Flexible Fixation with Locking Plates

By Michael Bottlang, PhD, Director, Legacy Biometrics Laboratory

Tuesday, January 4th, 2011

A 2004 editorial entitled ‘‘When Evolution Begets Revolution’’ described locking plates as the next great advance in orthopaedic traumatology that was adopted at an unprecedented speed [1]. The editorial concluded with the prudent prediction that ‘‘this wave of enthusiasm will surely be followed with an analysis of the inherent problems, followed by a truer understanding of the role of these implants.” Today, locking plates are recognized for the superior fixation strength of fixed-angle locking screws, particularly for metaphyseal fixation in osteoporotic bone. They furthermore support biological fixation, allowing subcutaneous plating while preserving periosteal perfusion. Hence, they satisfy two out of three principal aspects of fracture fixation, being stable fixation, preservation of biology, and promotion of fracture healing.

The latter aspect of fracture healing is increasingly being recognized as an inherent problem of the current generation of locking plates. If locking plates do not provide a mechanical environment that promotes fracture healing, they become prone to losing the race between healing and fixation failure, leading to late implant breakage and loss of fixation. There is growing evidence from clinical and animal studies that the inherent stiffness of a locked plating construct can suppresses fracture motion to a level that is insufficient to promote fracture healing by callus formation [2-4].

With hindsight, locked bridge plating constructs pose an apparent conundrum: They provide inherently rigid stabilization, yet they should facilitate secondary bone healing that relies on flexible fixation to stimulate callus formation. To resolve this conundrum, we developed a modified locked plating concept, termed Far Cortical Locking (FCL) that enables flexible fixation with locking plates [4,5]. FCL reduces the stiffness of a locked plating construct by means of FCL screws that are fixed in the plate and in the far cortex while retaining a controlled motion envelope in the near cortex of a diaphysis. FCL screws have a flexible shaft with a reduced diameter that can elastically deflect within the near cortex motion envelope. The motion envelope is controlled by the diameter of a collar segment adjacent to the FCL screw head. FCL constructs therefore resemble a monolateral external fixator, the bar of which has been applied close to the bone surface and the pins of which are secured in the far cortex rather than in the near cortex.

A biomechanical study has shown that FCL screws reduce the stiffness of locked plating construct by over 80% while retaining comparable strength [5]. An in vivo study has furthermore shown that FCL constructs reliably yielded bridging of all cortices, causing healed fractures to be 156% stronger than control fractures stabilized with standard locked plating constructs [4]. Most interestingly, standard locked constructs suppressed fracture healing at the cortex under the plate where fracture motion is minimal. A clinical study is currently being conducted to document the effect of FCL screws on healing of supracondylar femur fractures.

The facts that controlled interfragmentary motion can promote fracture healing while absence of motion will suppress callus formation have long been recognized in the external fixator literature, particularly by the landmark studies of Goodship and Kenwright [6] and Claes [7]. As such, the evolution of locked plating towards more flexible fixation is both novel and conservative. If clinical results should support the prior finding on improved healing with FCL, they will likely inspire a variety of implant solutions aimed at providing flexible fixation with locking plates. These solutions will be key for the quest on flexible fixation with locking plates. However, solutions should be supported by evidence on their ability to promote fracture healing while ensuring that flexible fixation is not gained on cost of fixation strength. Such next generation of flexible locking plates will resemble true internal fixators that replicate the biomechanical behavior of external fixators by allowing adequate interfragmentary motion to promote the natural fracture healing cascade via callus formation. It is the hope of the author that this evolution will in turn resolve the misnomer “secondary” bone healing by recognizing the prime importance of this natural healing cascade for the vast majority of fractures.

Dr. Bottlang is the Director of the Legacy Biomechanics Laboratory in Portland, OR, USA. His research is focused on orthopaedic trauma and fracture care. His line of research on FCL was funded by the NIH and has received the Award of Excellence at the 2010 meeting of the American Association of Orthopaedic Surgeons. He holds several patents and has contributed to the development of several devices, including Zimmer “MotionLoc” FCL screws for which he receives royalties.

Note:  Listings of the MotionLoc FCL screws and the NCB Polyaxial Plate can be found on OrthopaedicLIST.com and x-ray examples of plate and screw fixation of fractures can be seen in the OrthopaedicLIST.com Implant Identification section.

[1] Sanders R. When evolution begets revolution. J Orthop Trauma. 2004;18:481-482.

[2] Henderson CE, Bottlang M, Marsh JL, Fitzpatrick DC, Madey SM. Does locked plating of periprosthetic supracondylar femur fractures promote bone healing by callus formation? Iowa Orthop J. 2008;28:73-6.

[3] Lujan TJ, Henderson CE, Madey SM, Fitzpatrick DC, Marsh JL, Bottlang M. Locked plating of distal femur fractures leads to inconsistent and asymmetric callus formation. J Orthop Trauma. 2010;24-3:156-62.

[4]  Bottlang M, Lesser M, Koerber J, Doornink J, von Rechenberg B, Augat P, Fitzpatrick DC, Madey SM, Marsh JL. Far cortical locking can improve healing of fractures stabilized with locking plates. The Journal of bone and joint surgery. 2010;92:1652-1660.

[5] Bottlang M, Doornink J, Fitzpatrick DC, Madey SM. Far Cortical Locking can reduce the stiffness of locked plating constructs while retaining construct strength. J Bone and Joint Surg. 2009; 91(8):1985-1994.

[6] Goodship AE, Kenwright J. The influence of induced micromovement upon the healing of experimental tibial fractures. J Bone Joint Surg Br. 1985;67-4:650-5.

[7] Claes LE, Wilke HJ, Augat P, Rubenacker S, Margevicius KJ. Effect of dynamization on gap healing of diaphyseal fractures under external fixation. Clin Biomech (Bristol, Avon) 1995;10-5:227-34.

Costs and Rationing: Issues to Address

by Augusto Sarmiento, M.D.

Thursday, April 14th, 2011

The medical profession and the lay community continue to be bombarded on a daily basis with information arising from a myriad of opinions dealing with the escalating costs of care, which according to many, has reached unaffordable and unsustainable levels. Medical care cost has soared to the point where it is responsible for 16% of the national budget expenditures.

The resulting confusion paralyzes progress, while the condition becomes exponentially worse.       For people who like me, possessing only limited understanding of the complexity of the issues involved, all we can do is try to gain additional meaningful knowledge so that when we express individual opinions our voices have a better change of being heard. With that attitude in mind, I discuss my perceptions on two issues where the medical profession can play a major role: rationing of medical care and abuse of services.

The mere mention of rationing provokes an immediate and oftentimes violent reaction from which politicians and extremists readily take advantage. This issue, steeped in cultural and traditional religious reasons, has prevented a serious and candid analysis of its true meaning. Furthermore, it precludes efforts to determine whether or not the time has come for the citizenry of this country to consider if a system with elements of rationing, but without abandoning its foundations, can be found. It is rather sophomoric to negate that several other highly advanced counties around the world have done such a soul searching and adopted health-care delivery mechanisms that ration services but have continued to provide good medical care while lowering its costs. This has been done without compromising basic human values and sensitivities.  In America, the state of Oregon has had in place during the past few years a system with elements of rationing which other states hopefully are carefully studying.

One area where rationing must be carefully and dispassionately addressed is the so-called end of life care. It has been documented that at this time 95% of healthcare dollars are spent in the last 30 days of life. How it is possible is that such an egregious and incomprehensible figure cannot be brought to the center of the political debate rather than deliberately keeping it away from the discussion table?

To look at rationing only as vehicle to reduce health care cost is not appropriate. Objectivity and common sense in related matters are also very important. As physicians we were told from the first days in medical school that uppermost in our professional life we had the responsibility to use all available means to preserve life, never to give up, and adherence to the principle of “Primum non nocere.” However, we much too often lose objectivity and find it difficult to act in a manner that at first glance seems to run contrary to traditional  precepts and values.

A visit to a Surgical Intensive Care Unit is a vivid example of the many times when our commitment to prevent death makes us follow irrational routes. Does it make sense to keep alive for weeks and weeks an octogenarian barely alive, suffering from a long history of debilitating medical conditions, who now suffers from the effects of a stroke? Why is it that these hospital units are always full of patients, many of whom never return home?

The answers given to this reality are not of a universal nature. There are times when the attending physicians sincerely believe that discontinuing the respirator and feeding tubes is not necessarily right since recoveries from the recent event is possible and justify continuing treatment. At other times the treating doctors surrender to pressure from relatives who for reasons dictated by emotion refuse to accept the verdict that life is no longer possible to maintain. Unfortunately, there are other times when keeping such patients under care brings financial benefits to the treating physicians and hospital.

In my case it is difficult to intelligently verify the latter situation because I have never spent time in Intensive Care Units as part of my professional work. I base my suspicion on observations of the manner in which some dishonest surgeons perform major elective surgical procedures, such as total hip or knee replacement, in elderly patients that can be satisfactorily managed symptomatically. Many of these patients die during their hospitalization or shortly afterwards. The greed and avarice of these people result in enriching their pockets.

If a truly confidential polling were to be conducted regarding the need to develop a sensible and humane system to prevent the futility of unrealistic prolongation of life, I suspect the vast majority of people with a modicum of intelligence and education would agree that rationing of some degree would be welcome. Likewise, a comparable means to prevent the performance of unnecessary surgery would be applauded.

Acceptable systems can be structured, though very difficult to gain wide and rapid acceptance. In the case of the end of life issues it would take a coordinated effort where representatives from various segments of the government, religious and educational organizations, the media, the medical profession and society as whole would get together to as dispassionately as possible to educate each other on the seriousness of the problem at hand and the unintended consequences likely to come from a refusal to address it.

When it comes to the abuse of expensive and unnecessary diagnostic and therapeutic modalities and surgeries, the medical profession has the moral power to play a major role in the resolution of the crisis. It would take, however, a deliberate effort to set aside the fruitless perpetuation of the concept that medicine is no longer a profession but a business to be squeezed to the maximum. Organized medicine would play a most pivotal place by divorcing itself from the control of education, research, and patient care that it selfishly relegated to the pharmaceutical and surgical implant industry. Through meaningful mechanisms to prevent continued tolerance of what the Justice Department’s current investigation of what it calls “egregious ethical transgression” in the relationship between orthopaedics and industry, much could be accomplished. Forbidding individuals with conflicts of interest to hold office in organized administrative and educational organizations would be essential.

Dr. Sarmiento is the former Professor and Chairman of Orthopaedics at the Universities of Miami and Southern California, and past-president of the American Academy of Orthopaedic Surgeons.  He is a contributor to Implant Identification on OrthopaedicList.com and has guest authored a number of other articles for this blog.

Orthopaedics and Industry: An Issue in Need of Resolution

by Augusto Sarmiento, MD

Saturday, March 27th, 2010                                                            

“Reason should be the slave of passion.”     David Hume

It is inherent in our nature to believe that views we passionately hold on given issues are correct. However, much too often, eventually we find them wanting. This realization did not keep David Hume, the empiricist/pragmatist par excellence, and one of the most influential figures in the past five-hundred years, to conclude “Reason should be the slave of passion.” (Ref. 1).  The topic of this commentary is an example where I found myself wondering if my long-held conviction of the harm brought about by an inappropriate relationship between orthopaedics and Industry, now spread throughout most of the industrialized world, needed to be questioned and radically modified.

The United States’ Justice Department investigation of serious trespasses and unethical conduct in the relationship, already in its fifth year, does not seem to have had a meaningful impact (Ref. 2). All we hear is that most of the identified culprits had “resolved” the conflicts by claiming that the receipt of moneys from Industry was justified because they represented grants devoted to legitimate educational ventures. It is very likely that this argument was valid in some instances since many educators/researchers are honest and reputable members of the orthopaedic community. On the other hand it is naïve, at best, to believe such an excuse applies to all the accused individuals, particularly in light of the fact that many of the identified parties are not in any way involved in educational or research endeavors.

I have previously reported on episodes where I was either offered by high-industry representatives large amounts of money for the use of implants by the faculty of the department I shared at the time, or even larger funds for accepting to have a total hip prosthesis named after me even though I had nothing to do with its development. After refusing the dishonest “deals’, the response I got was, “But we do this all the time.” In the early 1970s I was invited by Industry to lecture in the capital cities of five Latin American countries. I declined on the grounds that I considered unprofessional the acceptance of the attractive offer. My reply was followed by a letter from the firm’s headquarters saying that they would not have any trouble finding someone to fill my place. I responded by saying that I was aware of the availability of others for such deeds and resentful of the fact his company seemed to consider orthopaedics a bordello, where the choice of a prostitute is simple and uncomplicated. (Ref. 3).

It is most demeaning to our profession that some of our representative organizations as well as directors of residency programs and other people occupying high positions in the hierarchy continue to perpetuate the situation. I suspect it would be very difficult to find at this time many heads of orthopaedic societies and directors of orthopaedic residency programs in America whose dependency in Industry is not significant.

A number of subterfuges are used to justify all kind of questionable activities. Sometimes funds are provided to academic programs to pay the salary of new Fellows and faculty members. Endowed chairs are accepted without hesitation in some places; in other instances the real funding source is camouflaged under the name of some “generous donor,” when the true funding source is Industry.

Would not be anything wrong with Industry’s “generosity” if it were not by the fact that Industry expects a great deal of say in the selection of topics for discussion and the choice of faculty. In addition, it economically compensates for the moneys given away by escalating the costs of their products (Ref. 4). Industry continues to win the battle. The subordination of the orthopaedic profession to Industry’s profit-driven wishes seems complete (Ref. 5).

However, throughout the land, there is a growing number of people in our discipline who are increasingly unhappy with the breakdown of the moral sphere and professionalism in our ranks, and the control of education by Industry. The increasingly large number of orthopaedists in private practice and many in the academic world are not getting sufficient support from their representative organizations, which have chosen to remain silent and comfortably continue to enjoy the status quo.

This crisis may soon become of a serious nature. We most respond with a loud and unequivocal chorus opposing the current practices. If we continue to simply limit our efforts to increasing our financial well-being and to dwell on self-serving pocketbook issues the future our heirs will inherit from us will be an unhappy one.

References:

1)  Hume, David. A treatise of human nature. Oxford, 1888

2) United States Justice Department. Christopher J. Christie. Press Release September 27, 2007

3)  Sarmiento A. Bare Bones. Prometheus, 2005.

4) Sarmiento A.  Medicine Challenged. Publish America,2009.

5)  Sarmiento A. Rise and Decline. JBJS (A) 91:2740-2,  2009.

Dr. Sarmiento is the former Professor and Chairman of Orthopaedics at the Universities of Miami and Southern California, and past-president of the American Academy of Orthopaedic Surgeons.  He is a contributor to Implant Identification on OrthopaedicList.com.

“Conflict of Interest”: What Does it Mean to You?

by Douglas Dirschl, MD

Saturday, May 16th, 2009

The term “conflict of interest” means many things to many people but, in the context of an orthopaedic department in an academic medical center, the term applies to the relationship we have with companies in the pharmaceutical and orthopaedic device industries. These companies do business with us and our hospitals (we buy, use, or prescribe their products) and, as in any sales industry, their representatives want to treat us – their customers – well.  Sounds like good customer service, right?

The problem is that the medical profession (physicians and hospitals in particular) is being held to a higher standard regarding conflict of interest than most other professions or industries. Governmental agencies, consumer groups, patients, and law enforcement agencies are increasingly concerned with assuring that those providing healthcare services to patients are not being unduly influenced by the pharmaceutical or device industries. In almost no industry is it legal to accept a monetary “kick-back” for using or buying a specific company’s products, but in healthcare it is even being questioned whether seemingly insignificant gifts – such as pens, lunches, or notepads – might unduly influence the prescribing/ordering habits of a physician providing care for a patient.

We may each have our own opinion as to whether this is fair or unfair. We may each agree or disagree with the research done on the topic indicating that even small gifts can influence a buyer’s attitude towards a seller. We cannot, however, deny that this topic is getting a lot of national attention right now. The US Department of Justice has raised it to the “top of our minds” with allegations against companies for making – and physicians for accepting – improper payments. The American Association of Medical Colleges, the American Medical Association, and just about every other national medical association and industry group have gone on record stating that conflict of interest is an important topic that should be watched and managed carefully. Some academic institutions have gone so far as to ban ALL gifts from their campuses; for example, Yale University School of Medicine prohibits any pens, notepads, lunches, or any other gift in its medical center. Stanford University has taken it one step further, announcing last month it would not allow industry support for any educational activities conducted within its medical school or healthcare system.

So, what does this mean for us in our daily professional lives? Where will it end? Will CME as we know it disappear due to loss of industry support? I don’t know the answer to these questions, but I do know that we all need to acknowledge and understand that conflict of interest is an important issue that many of our patients will be in tune with.  We should be cautious about having, in patient care areas, items that clearly show a manufacturer’s name or logo, as some patients will interpret this as a conflict of interest.  Calendars, notepads, pens, scissors, models – anything that has a company’s name on it, should not be openly displayed in patient care areas. If a patient sees and asks about such items, we should not remark glibly that “they give those to us all the time”, but remind the patient that some items are important to carrying out patient care (such as models, notepads, scissors, etc).

I’m afraid that conflict of interest is a topic we can no longer ignore – it won’t go away. It is a train on a track and is headed right for us. Most medical schools, most medical associations, and most medical companies in the United States are in the process of revising their policies on conflict of interest. While this may be frightening because it may change daily professional life for us, it is probably wise that the “House of Medicine” tackle this issue in a proactive way.  If our own profession does not take an active role in providing a satisfactory response to this issue, then is it likely the federal government will define policies on conflict of interest for us. The only thing worse than having to do things a bit differently would be having the government dictate to us how to do them differently.

Dr. Douglas R. Dirschl is Frank C. Wilson Distinguished Professor and Chair of Orthopaedics at UNC School of Medicine. He also serves on the Own the Bone Steering Committee and chairs the Critical Issues Committee for the American Orthopaedic Association.

Avoiding 3 Common Audit Risks In EMRs

by Cheryl Toth, KarenZupko & Associates, Inc.

Thursday, June 10th, 2010

Digitizing your medical records is an effective way to improve practice workflow and reduce paper. But EMRs can also increase your risk of a documentation audit, unless you use their record keeping and automation features properly. Here are three risk areas that any orthopaedist who is evaluating, or using, EMR should be concerned with.

Risk #1: Poorly Designed Visit Templates

A critical component of successful EMR implementation is customizing the vendor’s visit templates. But many surgeons skip or abdicate this step. A large spine practice we worked with passed the task off to its non-clinical Practice Administrator. It should have been no surprise that the surgeons found the templates useless.

Why is customization so important? Standard visit templates create multi-page notes that don’t necessarily document what you did. The exam template for a spine surgeon bears little resemblance to what a foot and ankle surgeon needs. Templates are the most critical step toward making sure your documentation is right; bypass their customization at your own peril.

Vendors often aren’t much help in this area. Better to print an ICD-9 frequency report to identify the conditions you see and treat most often, and create a template for each of them in your new system.

 Risk #2: ‘Cloning’ 

Touted as a time-saver, EMRs automatically ‘pull forward’ the History of Present Illness (HPI) documentation from each previous patient encounter. That’s ok as long as you review and update the HPI for the current encounter. But when surgeons get busy, this step can be forgotten.

Letting the EMR pull the previous history into an auto-generated form without reviewing it is risky because E&M documentation guidelines state that each record must stand on its own. You’ve got to pay close attention to what is being pulled forward because the patient problem could be completely different. Cloning also creates a verbose chart note that contains rote responses, which don’t necessarily call out pertinent positives.

How do you deal with cloning? Make sure you factor into your workflow the essential step of reviewing HPI at every visit, and making updates to the documentation that the EMR has ‘pulled forward.’

 Risk #3: Coding Calculators

 Don’t assume the coding calculator algorithm in your EMR is generating the correct code. Some of these put practices at risk by suggesting code levels that don’t match what was documented.

A seven-surgeon orthopaedic group in Minnesota noticed an increased number of high level E&M codes after their EMR go-live. The practice conducted an internal audit and realized the algorithm on the medical decision-making component was incorrect. Luckily, they had a savvy billing office that picked up on the error and overrode it with the correct, lower level E&M code.

Orthopaedists should be concerned about this. Medicare recently said that, in the past three years, it processed a greater percentage of 99214 and 99215 code in almost all specialties. According to Part B News, the ‘proliferation’ of EHRs ‘allows easier documentation,’ thereby justifying higher E&M levels. It’s likely Medicare may target these code levels for an audit sooner rather than later.

What to do? Ask the vendor to create and code few chart notes using some of your current documentation, and verify that the codes ‘calculated’ match what you billed.

 The American Academy of Orthopaedic Surgeons’ June issue of AAOSNow features interviews with nationally-recognized auditorsand coding educators discussing these documentation risks and how to deal with them. Heeding this advice can reduce your audit risk exposure and improve EMR success.

Cheryl Toth is a consultant with KarenZupko & Associates, Inc. and wrote this article as a guest author for OrthopaedicLIST.com.  She helps practices implement and adopt technology in order to work smarter and more efficiently.  KarenZupko & Associates, Inc. is a national leader at providing coding and documentation audits, training, and consultations.

Ischemic Optic Neuropathy (ION)

by James W. Ogilvie, MD

Thursday, November 26th, 2009

 Ischemic optic neuropathy (ION) is a disorder than can occur following surgical procedures. There is partial or complete loss of vision as the result of a vascular insult. It has several possible etiologies including thrombosis of the central retinal artery most commonly associated with giant cell arteritis. Direct trauma to the orbit and cortical blindness must also be considered. ION has also been reported with acute non-surgical blood loss and the use of Viagara™. Hippocrates gives an account of someone with acute hematemesis who subsequently lost their sight, perhaps the first report of ION.

The least common and most enigmatic cause of post-operative vision loss is an ischemic episode to the optic nerve heads which are supplied by the short posterior cilliary arteries. The diagnosis of ION is made by fundoscopic examination of the eye in someone who reports a visual field defect following surgery. Emboli in the retinal vessels (posterior ION) can be visualized while in anterior ION (That which occurs anterior to the cribriform plate.) there are no initial diagnostic findings. After several months there is visible atrophy of the optic nerve heads resulting in a pale retina.

Because there may be effective therapies for other causes, it is important to differentiate ION from other etiologies of visual loss. An ophthalmologic consultant can accurately make the diagnosis. To date there is no effective treatment for anterior ION. Many therapeutic trials have been performed including the use of steroids, osmotic agents, hyperbaric oxygen, vasodilators and surgical decompression, all without benefit. There may be some spontaneous improvement in visual fields, but recovery from no light perception is very rare.

The causes of ION are not well understood, but acute blood loss is the most constant finding. ION has been reported with surgery in the supine, sitting and prone position. Prolonged spinal surgery in the prone position is the other commonly reported factor. Long surgical procedures resulting in facial edema when accompanied by hypotension or low hematocrit is often encountered in cases of ION. While atherosclerosis or diabetes may be predisposing factors, the relationship has not been studied in a scholarly fashion and ION has been reported in adolescents undergoing scoliosis surgery.

There is speculation that with acute blood loss there is an idiosyncratic response from released endogenous vasoconstrictors which may cause vasospasm of the short posterior cilliary vessels. It is not a sympathetic nervous system response due to the fact that sympathetic nerves do not supply the short posterior cilliary arteries. There may also be a congenital predisposition to ION due to a reduced ratio of capillary vessels to optic nerve heads. Unfortunately, there are no pre-operative tests to identify those with an increased susceptibility to ION.

Prevention of ION is clearly preferable. Reducing facial edema with the use of the reverse Trendelenburg position, limiting the use of crystalloids for fluid resuscitation and avoiding hypotension or anemia may lessen the incidence of ION.

ION frequently results in a medical liability action. If there are irregularities in the anesthetic record such as prolonged anemia or hypotension, use of large amounts of crystalloid for fluid resuscitation resulting in facial edema or improper patient positioning, the surgical team is often held liable. The issue of informed consent is often raised. What responsibility for discussing visual loss lies with the surgeon and anesthesiologist? There are no absolute answers to this issue, however this question should be settled long before discovery depositions are taken, preferably prior to the surgery itself.

     The guest author of this article for OrthopaedicList.com is Dr. James Ogilvie, a board certified orthopaedic surgeon.  He is Professor, Department of Orthopaedic Surgery, at the University of Utah in Salt Lake City and Professor Emeritus, Department of Orthopaedic Surgery, at the University of Minnesota in Minneapolis, MN. He is Staff Surgeon / Attending Staff at Shriners Hospital Intermountain Unit in Salt Lake City.

     A more detailed article on ION by Dr. Ogilvie can be found by clicking on the following link to it in the October 2009 issue of the American Academy of Orthopaedic Surgeons newsletter “AAOS Now”.

Thromboprophylaxis in Orthopaedic Surgery

Richard J. Friedman, MD, FRCSC

Saturday, March 5th, 2011

Abstract

Venous thromboembolism is a serious complication after total hip or knee surgery and there is a well-established clinical need for thromboprophylaxis. However, in a large number of cases adequate administration of thromboprophylaxis does not seem to occur after total joint arthroplasty. A major challenge in the management of thromboprophylaxis is to balance the benefits of treatment with the risks, including bleeding complications. Another potential barrier to the optimal use of thromboprophylaxis could be the inconvenience of currently available agents. Many surgeons therefore adopt a conservative approach towards thromboprophylaxis. Simplifying therapy with more convenient, efficacious and safe anticoagulants could change attitudes to anticoagulant use, and improve adherence to thromboprophylactic guidelines.

Introduction

Venous thromboembolism (VTE) is a serious complication after major orthopaedic surgery [1]. The rates of venographic deep vein thrombosis (DVT) and proximal DVT 7 to 14 days after major orthopaedic surgery in patients who receive no thromboprophylaxis are approximately 40% to 60% and 10% to 30%, respectively [1]. The manifestation of DVT is, to some extent, a consequence of bone damage during surgery, when procoagulant debris triggers thrombin generation, resulting in hypercoagulability [2]. In addition to hypercoagulability, the other components of Virchow’s triad of venous stasis and endothelial damage are also thought to play a part in thrombosis [3]. Thus, there is a well-established clinical need for thromboprophylaxis after arthroplasty [1].

A major challenge in the management of anticoagulants is to balance the benefits of treatment with the risks, including bleeding complications. Many surgeons appear concerned about postoperative bleeding and tend to adopt a conservative approach towards the relative risks and benefits of thromboprophylaxis [2]. Consequently, although evidence-based guidelines and recommendations advocate the use of anticoagulants after major orthopaedic surgery, thromboprophylaxis is still used suboptimally [4–6]. However, the evidence that careful prophylaxis administered at an appropriate time after surgery causes surgical bleeding is sparse [7]. In this review, current trends in thromboprophylaxis after orthopaedic surgery in the United States (US) are described. Factors limiting appropriate implementation of thromboprophylaxis regimens are also discussed 

Current Standard of Care

Further to the consensus document developed by the National Institute of Health in 1986 [8], there have been a series of American College of Chest Physicians (ACCP) guidelines published on the use of pharmacological agents for thromboprophylaxis after total hip arthroplasty (THA) and total knee arthroplasty (TKA), last updated in 2008 [1].

In the US, the available options for anticoagulation and thromboprophylaxis after elective THA or TKA are the vitamin K antagonists (VKAs, e.g. warfarin), the low molecular weight heparins [LMWHs]), and fondaparinux (an indirect Factor Xa inhibitor). Each of these options is associated with significant limitations that complicate use in clinical practice. VKAs have been the mainstay of oral anticoagulant therapy for more than 60 years [9]. However, VKAs have unpredictable pharmacokinetics and pharmacodynamics, and significant inter- and intrapatient variability in dose–response relationships. They are associated with multiple drug–drug and food–drug interactions and have a narrow therapeutic window [9]. Regular coagulation monitoring is therefore required to ensure that the international normalized ratio is within the recommended range of 2.0 to 3.0. The heparins are administered subcutaneously, which means patients often require daily appointments or a nurse visit to administer their medication. LMWHs are also associated with the risk of developing heparin-induced thrombocytopenia [10]. Fondaparinux is also administered subcutaneously, and is contraindicated in patients with severe renal impairment and in those that weigh less that 50 kg. In patients over the age of 75 who have undergone THA or TKA, fondaparinux causes an increased risk of bleeding [11].

The timing of initiation of prophylaxis depends upon the type of anticoagulant used. Warfarin therapy is generally initiated prior to surgery because of its delayed onset of action, whereas prophylaxis with LMWH can be started 10–12 hours before or 12–24 hours after surgery. There does not seem to be a clear advantage with either regimen, and both regimens are recommended by the ACCP [1]. Thromboprophylaxis is recommended to continue for at least 10 days after joint replacement surgery, with extended prophylaxis for up to 35 days recommended for those patients undergoing THA surgery and with a suggestion that thromboprophylaxis for up to 35 days could be beneficial for those undergoing TKA [1]. Traditionally, thromboprophylaxis used to continue only until the patient was discharged from hospital [12], despite the fact that this could be a suboptimal duration [13] and the risk of DVT and mortality after discharge is considerable [14, 15]. The median length of stay in US hospitals is now as short as 3 days after THA and 4 days after TKA [16]. A retrospective study of the medical records of 3,778 orthopaedic surgery patients found that 88% were discharged from hospital and prescribed warfarin or acetylsalicylic acid [6].

Suboptimal Utilization of Thromboprophylaxis

Despite the fact that thromboprophylaxis is now recommended for routine use after total joint arthroplasty, it is not always used optimally. Approximately 10% of patients received inadequate in-hospital thromboprophylaxis, and approximately 33% received inadequate post-discharge thromboprophylaxis according to findings from the US Hip and Knee Registry (1996–2001) [17]. An analysis of the data from the multinational Global Orthopaedic Registry (GLORY) to evaluate the compliance of surgeons with the ACCP guidelines for the prevention of VTE showed that only 47% of THA patients and 61% of TKA patients received prophylaxis in accordance with the recommended start time, duration and dose/treatment intensity recommended by the guidelines [16]. Although nearly all patients received prophylaxis on the first day after surgery, more than a quarter did not receive any form of prophylaxis 7 days after surgery [18].

 

Suboptimal thromboprophylaxis decreases patient outcomes, resulting in many patients remaining at unnecessary risk of thrombosis and its complications [4]. The reasons for lack of compliance with the guidelines may be numerous. They include lack of awareness, poor understanding or disagreement with guidelines (either specifically or as a general concept), resistance to changing established practices, and doubt that a new approach will change outcomes. Established surgeons may also be reluctant to use new anticoagulant regimens because of a fear of increased bleeding risk [17]. Attitudes may also limit a physician’s willingness to follow guidelines. An awareness of the guidelines does not necessarily mean physicians have sufficient knowledge to critically evaluate and apply recommendations [4].

Other potential barriers include the mistaken belief that a small asymptomatic DVT is not important because it cannot cause clinically significant pulmonary embolism (PE) [19], which fortunately is only held by a minority [20]. Due to the often clinically silent nature of VTE, and the low incidence of VTE during the short postoperative hospital stay, the chances of a surgeon witnessing a major DVT or an acute PE are rare [4]. In addition, the trend towards earlier hospital discharge means that many symptomatic events occur after that time [21, 22], and patients are often seen by other specialists when referred back to hospital with a venous thromboembolic event; therefore, surgeons are often unaware of the true incidence of VTE in their patients.

Long-term sequelae of VTE are frequent and often disabling [23]. Recurrent VTE can occur after surgery, although the incidence is less than in other patients groups such as those with cancer [24]. Thrombosis damages the deep venous valves resulting in venous reflux and venous hypertension of the lower limbs. This residual venous obstruction and inflammation are thought to be responsible for the development of post-thrombotic syndrome [25, 26]. Chronic thrombotic pulmonary hypertension, which is associated with considerable morbidity and mortality, occurs in approximately 3–4% of patients over 2 years after a symptomatic PE [27].

Economic Impact of Venous Thromboembolism

The acute and chronic phases of VTE related care have substantial economic consequences [28, 29] that can be effectively modeled [30]. A recent study found the total annual healthcare cost for a VTE ranged from $7,594 to $16,644, depending on the type of event and whether it was a primary or secondary diagnosis. The hospital readmission rates for DVT or PE within 12 months were 5.3% for primary and 14.3% for secondary diagnoses [31]. These data indicate that thromboprophylaxis with anticoagulants should not only be beneficial to patients, but could also be cost effective for the healthcare system [32, 33].

Need for More Convenient Anticoagulants

Another potential barrier to the optimal use of thromboprophylaxis could be the inconvenience of currently available agents [34]. Orthopaedic surgeons and their patients would benefit from an oral anticoagulant that could be administered in fixed doses [35].

Simplifying Therapy

Non-compliance can result in a poor quality of life and increased medical expenditures in managed care. In a study of diabetic patients, total medical costs were approximately $4,500 for patients at 80–100% adherence compared with approximately $8,900 for those at 1–19% adherence [36]. A variety of factors affect non-compliance, but simplifying treatment has been shown to improve adherence in asthma patients [37] and cardiovascular patients given single-pill amlodipine/atorvastatin were found to be approximately three times more likely to achieve adherence over 1 year of follow-up than patients given a two-pill regimen [38]. Similarly, simplifying therapy to a once-daily regimen in virologically suppressed HIV-1-infected patients improved adherence and patient satisfaction [39].

Novel Anticoagulants

Anticoagulants in development are targeting different steps in the coagulation pathway to provide simpler alternatives to currently available anticoagulants. Among these new agents are direct thrombin inhibitors and direct Factor Xa inhibitors [40]. The direct thrombin inhibitor dabigatran etexilate appears an attractive alternative to the current standard of care in patients after THA and TKA [41–44]. It has been granted marketing authorization in the European Union and Canada for the prevention of VTE after THA or TKA. The manufacturer’s recommended dose is 220 mg once daily (starting 1–4 hours after surgery with a single 110 mg capsule) for a total of 28–35 days after THA or a total of 10 days after TKA [45]. Direct Factor Xa inhibitors in development include rivaroxaban, apixaban, edoxaban (DU-176b), and YM150, and of these rivaroxaban is in the most advanced stage of development [46]. Rivaroxaban has shown potential as a once-daily, oral anticoagulant that may be administered in fixed doses for the prevention and treatment of thromboembolic disorders following orthopedic surgery [47–52]. Rivaroxaban is approved in more than 90 countries worldwide, including the European Union and Canada, for the prevention of venous thromboembolism after elective hip or knee replacement surgery in adult patients. A dose of 10 mg once daily (with the initial dose 6–10 hours after surgery, provided that hemostasis has been achieved) for 5 weeks after elective hip arthroplasty or 2 weeks after elective knee arthroplasty is recommended by the manufacturer [53].

 

The main difference between direct thrombin inhibitors and direct Factor Xa inhibitors is their mechanism of action. They also differ in their pharmacokinetic and pharmacodynamic profiles, such as metabolism. For example, in the case of dabigatran, more than 80% of the systemically available drug is eliminated by renal excretion [54]. Two–thirds of administered rivaroxaban is metabolized to inactive metabolites (half of this is eliminated via the kidneys and half via the fecal route), and one–third is excreted as unchanged active drug in the urine [55].

 

Conclusion

The need to use thromboprophylaxis after major orthopaedic surgery is now becoming well recognized. However, adequate administration of thromboprophylaxis regimens does not seem to occur after total joint arthroplasty in a large number of cases. The reasons for this appear complex, involving surgeons’ poor awareness of the problem of post-surgical thrombosis, their attitudes to guidelines, concerns about causing bleeding, and the complexities of anticoagulation with current agents. Simplifying therapy, such as once–daily fixed dosing, could change attitudes to anticoagulant use and improve adherence to guidelines. Newly developed, oral, fixed-dose anticoagulants should enable substantial improvement in thromboprophylaxis usage, thereby improving patient outcomes. The primary drawback of the new anticoagulants, particularly those with a long half-life, is the lack of specific antidotes to reverse their anticoagulant effect[56]. Specific antidotes might be needed in particular situations such as for overdose or emergency surgery. However, this may not pertain to dabigatran and rivaroxaban as they have relatively short half–lives (12–14 hours and 7–11 hours, respectively) [45, 53]. As off-label prescribing is not uncommon, there is a risk that new anticoagulants licensed for thromboprophylaxis after THA or TKA will be prescribed for unlicensed indications [57]. These current challenges could be overcome by finding specific antidotes and post-approval surveillance of off-label prescribing.

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29.       K. K. Knight, J. Wong, O. Hauch, G. Wygant, D. Aguilar, and J. J. Ofman, “Economic and utilization outcomes associated with choice of treatment for venous thromboembolism in hospitalized patients,” Value Health, vol. 8, no. 3, pp. 191–200, 2005.

30.       S. D. Sullivan, S. R. Kahn, B. L. Davidson, L. Borris, P. Bossuyt, and G. Raskob, “Measuring the outcomes and pharmacoeconomic consequences of venous thromboembolism prophylaxis in major orthopaedic surgery,” Pharmacoeconomics, vol. 21, no. 7, pp. 477–496, 2003.

31.       A. Spyropoulos, “Direct medical costs of venous thromboembolism and subsequent hospital readmission rates: an administrative claims analysis from 30 managed care organizations,” Journal of Managed Care Pharmacy, vol. 13, no. 6, pp. 475–486, 2007.

32.       B. Detournay, A. Planes, N. Vochelle, and F. Fagnani, “Cost effectiveness of a low-molecular-weight heparin in prolonged prophylaxis against deep vein thrombosis after total hip replacement,” Pharmacoeconomics, vol. 13, no. 1 Pt 1, pp. 81–89, 1998.

33.       G. Agnelli, M. R. Taliani, and M. Verso, “Building effective prophylaxis of deep vein thrombosis in the outpatient setting,” Blood Coagulation and Fibrinolysis, vol. 10 Suppl 2, pp. S29–S35, 1999.

34.       B. I. Eriksson, D. J. Quinlan, “Oral anticoagulants in development: focus on thromboprophylaxis in patients undergoing orthopaedic surgery,” Drugs, vol. 66, no. 11, pp. 1411–1429, 2006.

35.       J. I. Weitz, “Emerging anticoagulants for the treatment of venous thromboembolism,” Thrombosis and Haemostasis, vol. 96, no. 3, pp. 274–284, 2006.

36.       M. C. Sokol, K. A. McGuigan, R. R. Verbrugge, and R. S. Epstein, “Impact of medication adherence on hospitalization risk and healthcare cost,” Medical Care, vol. 43, no. 6, pp. 521–530, 2005.

37.       A. Gillissen, “Patients adherence in asthma,” Journal of Physiology and Pharmacology, vol. 58, no. Suppl 5, pp. 205–222, 2007.

38.       B. V. Patel, R. S. Leslie, P. Thiebaud, et al., “Adherence with single-pill amlodipine/atorvastatin vs a two-pill regimen,” Vascular Health and Risk Management, vol. 4, no. 3, pp. 673–681, 2008.

39.       B. A. Boyle, D. Jayaweera, M. D. Witt, K. Grimm, J. F. Maa, and D. W. Seekins, “Randomization to once-daily stavudine extended release/lamivudine/efavirenz versus a more frequent regimen improves adherence while maintaining viral suppression,” HIV Clinical Trials, vol. 9, no. 3, pp. 164–176, 2008.

40.       J. Ansell, “Factor Xa or thrombin: is factor Xa a better target?,” Journal of Thrombosis and Haemostasis, vol. 5 Suppl. 1, pp. 60–64, 2007.

41.       B. I. Eriksson, O. E. Dahl, N. Rosencher, et al., “Oral dabigatran etexilate vs. subcutaneous enoxaparin for the prevention of venous thromboembolism after total knee replacement: the RE-MODEL randomized trial,” Journal of Thrombosis and Haemostasis, vol. 5, no. 11, pp. 2178–2185, 2007.

42.       J. S. Ginsberg, B. L. Davidson, P. C. Comp, et al., “Oral thrombin inhibitor dabigatran etexilate vs North American enoxaparin regimen for prevention of venous thromboembolism after knee arthroplasty surgery,” Journal of Arthroplasty, vol. 24, no. 1, pp. 1–9, 2009.

43.       B. I. Eriksson, O. E. Dahl, N. Rosencher, et al., “Dabigatran etexilate versus enoxaparin for prevention of venous thromboembolism after total hip replacement: a randomised, double-blind, non-inferiority trial,” Lancet, vol. 370, no. 9591, pp. 949–956, 2007.

44.       B. I. Eriksson, R. Friedman, “Dabigatran Etexilate: Pivotal Trials for Venous Thromboembolism Prophylaxis After Hip or Knee Arthroplasty,” Clinical and Applied Thrombosis/Hemostasis, vol. 15, pp. 25S–31S, 2009.

45.       Dabigatran Summary of Product Characteristics, “Pradaxa®(dabigatran etexilate) Summary of Product Characteristics,” http://www.pradaxa.com/Include/media/pdf/Pradaxa_SPC_EMEA.pdf, 2008.

46.       K. A. Bauer, “New anticoagulants,” Current Opinion in Hematology, vol. 15, no. 5, pp. 509–515, 2008.

47.       B. I. Eriksson, L. C. Borris, O. E. Dahl, et al., “A once-daily, oral, direct Factor Xa inhibitor, rivaroxaban (BAY 59-7939), for thromboprophylaxis after total hip replacement,” Circulation, vol. 114, pp. 2374–2381, 2006.

48.       W. Mueck, B. I. Eriksson, K. A. Bauer, et al., “Population pharmacokinetics and pharmacodynamics of rivaroxaban – an oral, direct factor xa inhibitor – in patients undergoing major orthopaedic surgery,” Clinical Pharmacokinetics, vol. 47, no. 3, pp. 203–216, 2008.

49.       B. I. Eriksson, L. C. Borris, R. J. Friedman, et al., “Rivaroxaban versus enoxaparin for thromboprophylaxis after hip arthroplasty,” The New England Journal of Medicine, vol. 358, no. 26, pp. 2765–2775, 2008.

50.       A. K. Kakkar, B. Brenner, O. E. Dahl, et al., “Extended duration rivaroxaban versus short-term enoxaparin for the prevention of venous thromboembolism after total hip arthroplasty: a double-blind, randomised controlled trial,” Lancet, vol. 372, pp. 31–39, 2008.

51.       M. R. Lassen, W. Ageno, L. C. Borris, et al., “Rivaroxaban versus enoxaparin for thromboprophylaxis after total knee arthroplasty,” The New England Journal of Medicine, vol. 358, no. 26, pp. 2776–2786, 2008.

52.       A. G. G. Turpie, M. R. Lassen, B. L. Davidson, et al., “Rivaroxaban versus enoxaparin for thromboprophylaxis after total knee arthroplasty (RECORD4): a randomised trial,” Lancet, vol. 373, no. 9676, pp. 1673–1680, 2009.

53.       Xarelto® Summary of Product Characteristics, http://www.xarelto.com/html/downloads/Xarelto_Summary_of_Product_Characteristics_May2009.pdf, 2009.

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Dr. Friedman is a Clinical Professor of Orthopaedic Surgery at The Medical University of South Carolina and Chairman of the Department of Orthopaedic Surgery of Roper Hospital, Charleston, SC, USA.  He is a world reknown leader in the prevention of deep vein thrombosis.

A Triumph of Matter over Mind

by Augusto Sarmiento, MD

January 25th, 2014 

The current pervasive and misguided infatuation with the idea that in the care of fractures it is indispensable to achieve perfect restoration of anatomy in all instances in order to obtain good clinical results continues to blind many in our profession. I have previously made reference to this obsession suggesting that we train our residents to be cosmetic surgeons of the skeleton rather than physicians/scientists1.

My belief that Orthopaedics is losing its scientific primacy and rapidly becoming an entirely technical discipline was reinforced a short time ago when I learned of a clinical situation where passion prevailed over reason with very likely adverse serious consequences.

The clinical case consisted of a 21 year old man who was involved in automobile accident rendering him paraplegic. In addition he had suffered bilateral comminuted, distal intraarticular fracture of both forearms. The fractures were treated by means of internal fixation using plates and screws as well as multiple pins that held together the diligently repositioned small fragment. Radiographs obtained following surgery demonstrating excellent reduction of the fractures.

For reasons not known to me, the surgeon chose to improve upon the fixation achieved from the plates and screws by placing on the dorsum of the patient’s right arm a long plate that extended from the neck of the third metacarpal to the mid-radius. Several screws filled the holes in the long plate. This plate, I was told, would be removed six weeks after surgery; therefore I assumed it was not intended to encourage fusion of the wrist.

I cannot express strong disagreement with the procedure performed for the care of the radius fractures that must have taken a great deal of time plus the likely possibility that the extensive dissection of the bony fragments could result in major stiffness of his wrists joints. After all this is the current party line. However, I cannot help but question the wisdom of inserting a plate that inevitably will increase the degree of limitation of motion of the wrist from which the patient will never completely recovered.

This very realistic scenario provokes an even greater discomfiture when one realizes that the young man was paraplegic and will remain paraplegic for the rest of his days. As such, his only mode of locomotion will be a wheel chair, from which he will transfer to his bed and automobiles. A bit of thought should have made the surgeon aware that transfer activities from a wheel chair require a significant degree of dorsiflexion of the wrists. In order to lift one’s body with the use of the hands, dorsiflexion of the wrists is essential. The young man, I anticipate, will not be able to do so, and if he masters s technique to accomplish the task it will be a very complicated and difficult one.

I have surmised that the surgeon performing the surgery was very likely a technically skillful one, but either because of his blind reliance on the virtues of internal fixation and perfect reapproximation of fragments, or lack of objectivity, he has condemned a young man to a disability greater than the one that the paraplegia had already imposed on him.2. It does not suffice to adhere to the aphorism expressed by Simon Bolivar, the Latin American liberator, “Good judgment comes from experience and experience comes from bad judgment”, at least not when we are dealing with the health and future of other human beings.

The rampant lack of objectivity, clearly demonstrated in this instance, can be improved if we, the educators, emphasize objective reasoning to our students. Unharnessed enthusiasm and fascination with surgical experiences must be tempered with reason. “La raison avant la passion”.

REFERENCES:

1.   Sarmiento A. The future of our specialty. Acta Orthopedica Scandinavica. 71 (6): 574-579, 2000

2.   Sarmiento A. Have we lost Objectivity?  Jour. Bone and Joint Surgery. Vol. 84A:  1254-58, 2002.

Dr. Sarmiento is the former Professor and Chairman of Orthopaedics at the Universities of Miami and Southern California, and past-president of the American Academy of Orthopaedic Surgeons.  He is a contributor to Implant Identification on OrthopaedicList.com and has guest authored a number of other articles for this blog.

The Dangers of Unchallenged Tradition

by Augusto Sarmiento, M.D

November 27th, 2013 

     Since for the first time I find myself with time in my hands I decided to dwell on exploring issues with which in the past I was involved to a major degree. Today I will discuss an issue where long-held, rigid adherence to an unchallenged tradition has forced me to challenge its validity.

My comment deals with the Colles fractures, which is one of the first subjects in orthopaedics we come into contact during our year of internship.  We learned about the ubiquitous fracture that affected a large number of older people and were told that its treatment was simple and the clinical results good.  All that was needed:  “closed reduction” and immobilization in a long arm cat for a few weeks.

It was not until late in my career that I first began to ask questions as to the etiology of the frequently observed loss of the obtained reduction. I had followed the gospel-like lessons we had learned from the British orthopaedist who forcefully stated that once the reduction had been obtained, the cast had to extend over the elbow, the forearm held in pronation and the wrist in a position of ulnar deviation and slight flexion.

One day, however, I suspected that the recommended position of the foreman in pronation in the cast was the guiltiest party. My logic was based on my understanding of the anatomy and physiology of the wrist. I reasoned that if it is true that muscles in order to function most effectively should be placed in a condition of tension then the forced pronation of the forearm would result in activation of the brachioradialis muscle, the only muscle attached to the distal radius, and in that manner recreate the deformity. The contraction of this muscle during flexion of the elbow could easily displace proximally and dorsally the distal radial fragment. 1

I met with the neurologist who was performing electromyography and asked him for his advice and help. I brought him volunteer medical students and patients to have the studies conducted.  Without exceptions, every time the elbow was flexed the brachioradialis muscle contracted. In cadaver specimens, where we had created fractures that resembled the Colles fracture pattern, any pull on the muscle readily recreated the typical deformity.

Based on all that information we began to treat Colles fractures in supination and compared the results with those obtained when treated in pronation. The results were published, which indicated a lower incidence of re-displacement in the supination group. We went as far as developing a foreman brace that permitted limited flexion of the elbow, but prevented pronation of the forearm. It permitted limited flexion of the wrist but made impossible any radial deviation. 2, 3 I concluded that the classical position as described by Colles and faithfully accepted by the orthopaedic community was wrong.

At that time my career took a major turn toward Hip surgery following  a three-month visit to Sir John Charnley in England that resulted in my concentrating more seriously on total hip replacement and ignoring to some degree my interest in wrist fractures. I deeply regret the foolish decision since I am sure I could have been able to continue to devote time to both subjects simultaneously.

I vividly recall that during those days of romancing with Colles fractures I visited with some regularity local Nursing Homes where I followed patients I had treated surgically for various conditions. Oftentimes I took along with me one or two residents. During those visits I made it a habit to ask as many patients as possible if they had at any time in their lives sustained fractures of their wrists. As expected, many of them had. I saw many where a close look failed to indicate any deformity whatsoever. Other times I observed obvious deformities.  However, I have no recollection of a single patient who presented symptoms of osteoarthritis or complained of any serious clinical problems as a result of the deformed wrist.

No doubt, my mind was conditioned not to question the wisdom of Colles and consequently I had rigidly adhered to his well-intentioned but erroneous premise. I suspect we do this very often with many other pronouncements and treatment which overtime gain an odor of sanctity that precludes questioning. This is why I am such a strong advocate of conditioning residents to ask questions and to challenge virtually everything we teach them.

During the last two decades a great deal of enthusiasm has grown in support of open reduction and internal fixation of Colles fracture. The readers would not be surprised to hear that I have not surrendered to the new treatment modality. However, I trust I am smart enough to realize that the technique has made possible the attainment of better anatomical reduction and restoration of articular congruity and in many occasions is the treatment of chicer. 

        Approximately 10 years ago I sustained a comminuted, intraarticular Colles fracture with a severe dislocation of the radio-ulnar joint.  My hand surgeon fixed the fracture with multiple wires. When I woke up from the surgery and glanced at the radiographs I immediately commented “This will never work.” My remark was based on the recognition that the dislocated radio-ulnar joint had not been addressed. The surgeon had concentrated on reduction of the fragments in the best possible way, but ignored the dislocation of the ulna, which was the most important feature. Good fragment reduction in the presence of a dislocated radio-ulnar joint is not enough, particularly if the distal-lateral radial fragment has an oblique geometry. The reduction is easily lost when the brachioradialis contracts    . That was exactly what happened. Ten days after surgery new x-rays demonstrated the recurrence of the radial deviation of the held-together distal epiphysial bones. Soon after that I was back in surgery where a plate was used to stabilize the bony fragments.

My feeling regarding the closed treatment of Colles fractures may soon become meaningless since the current infatuation with surgery is displacing the nonsurgical treatment into the heap of history. Or maybe not. We should not be surprised if within a few years the orthopaedic profession will conclude that plating was nothing but a flash in the pan when the technique is applied to all displaced fractures and that plate fixation should be reserved for the very severely comminuted fractures with associated radio-ulna dislocation. We are already learning that the results from routine surgery are not any better than those obtained from manipulation and close reduction. Economics may the fact that triggers the arresting of the trend. Equal pay for the care of those patients may become the law of the land regardless as to whether or not surgery is performed.

REFEERENCES:

  1. Sarmiento, A. The Brachioradialis as a Deforming Force in Colles’ Fractures Clin. Orthop. Rel. Res. 38:86-92, 1965.
  2. Sarmiento, A., Pratt, G.W., Berry, N.C. and Sinclair, Wm. F. Colles’ Fractures – Functional Bracing in Supination. J. Bone and Joint Surg. 57A:3,311-317, 1975.
  3. Sarmiento, A., Zagorski, J.B. and Sinclair, W.F. Functional  Bracing of Colles’ Fractures: A Prospective Study of Immobilization in Supination versus Pronation.  Orthop. & Rel.  Res. 146:175-187, 1980

Dr. Sarmiento is the former Professor and Chairman of Orthopaedics at the Universities of Miami and Southern California, and past-president of the American Academy of Orthopaedic Surgeons.  He is a contributor to Implant Identification on OrthopaedicList.com and has guest authored a number of other articles for this blog.

Saving Time and Making Better Informed Clinical Decisions

by Donna Flake, MSLS, MSAS, Director, SEAHEC Medical Library, Wilmington, NC 

Medical Librarians CAN save you time AND assist you in making better informed clinical decisions.

Medical Librarians have an essential role in health care.  They provide evidenced-based medical information to health professionals, enabling them to make better informed clinical decisions.

A recent JAMA article (Sept. 25, 2013), “The Evolving Role and Value of Libraries and Librarians in Health Care,” reported on a study of health professionals in which 71% of the respondents said they changed how they managed the care of a particular patient as a result of information provided by the health science library.

At many medical centers, medical librarians are actually going on rounds with physicians and medical residents, then providing evidenced-based medical information on the medical cases studied.  I did this with the Pediatric physicians and residents in a former job.

A landmark study was published in the Journal of the Medical Library Association in January 2013.  It demonstrates the importance, value, and cost savings of medical libraries, and medical librarians.  16,122 physicians, nurses, and other health professionals at 118 hospitals in the US and Canada responded to the survey.  The survey was designed to determine whether information obtained from library services was perceived as valuable and if the information was considered to have impacted patient care.  Here are some of the results:

  • 7% felt the impact was significant enough to reduce patient length of stay
  • 56% felt the knowledge helped avoid adverse events, such as hospital readmission, patient mortality, and additional procedures
  • 92% of health professionals said medical information provided through library services provided new knowledge
  • 95% of health professionals said medical information provided through library services resulted in the provider making a better informed clinical decision
  • 85% of physicians believed the information from the library saved, on average, 2.5 hours of their time
  • 84% of health professionals felt the knowledge contributed to a positive change in patient care, such as advice given to patient or choices of drugs

In Spring, 2013, I completed a user satisfaction survey on the SEAHEC Medical Library in Wilmington, NC.  Of the physicians who responded, 95% agreed that the information the library provided would have been difficult to obtain on their own.  Additionally, 75% agreed that the information the library or the library databases provided influenced decisions on patient care.  Below is a sampling of comments from my user satisfaction survey:

  • A physician stated:  “The library has been invaluable for research projects and articles submitted for publication.”
  • An OB/GYN resident stated:  “The librarians are very knowledgeable and helpful with journal articles and literature searches.”
  • A physician stated:  “The librarians provided excellent, prompt help.”
  • A nurse administrator stated:  “I’d never be able to find what I want due to lack of knowledge and/or time constraints.  My job would be so much more difficult without the library services.”
  • An administrator of the Emergency Department stated:  “Love our library, we couldn’t do without it.”

I encourage readers of this blog to contact their medical librarians – great things can happen!

Sources:

Sollenberger, J, Holloway, R.  The evolving role and value of libraries and librarians in health care.  JAMA Sept 25, 2013 310 (12): 1231.

Marshall, J, Sollenberger J, Easterby-Gannett S, et al.  The value of library and information services in patient care:  results of a multisite student.  J Med Lib. Assoc 2013 101 (1): 38-46.

Mrs. Flake is Library Director at the SEAHEC Medical Library in Wilmington, NC and renown for her work with libraries around the world.