Extreme Deformity Correction with TAA Alone

by James K. DeOrio, MD

Many ankle replacement systems are best used when the deformity does not exceed varus or valgus greater than 10 degrees and when there is minimal bone loss. However, that would exclude many ankles from being replaced which would leave ankle fusion as the only option. I have chosen to pursue one ankle replacement sytem whenever there is significant deformity. This modular intramedullary total ankle replacement is a fixed-bearing two-component design with a modular stem system for both tibia and talar components.  It is indicated for resurfacing of the ankle in severe inflammatory, traumatic or osteoarthritis. Contraindications include poor skin quality over the anterior ankle, peripheral vascular disease, paralysis and ongoing infection. The tibia is inserted into the intramedulary tibia, but does not resurface the malleoli.  The talar component entirely replaces the superior aspect of the natural talus, after a flat dome resection.  Multiple modular segments may be added to the tibial stem, depending on the surgeon’s determination of how much stability is needed or how much the stem should pass beyond a simultaneous supramalleolar osteotomy performed for tibial malunion.  The talar component’s stem may be limited to the body of the talus or can be can be extended across the subtalar joint into the calcaneus if greater support for the talar component is required or when a simultaneous subtalar arthrodesis is warranted.  The longer talar component calcaneal stem is not currently FDA approved and is only available after approval of compassionate use.

Unique to the modular intramedullary total ankle system is the alignment guide system. The ankle is opened identical to the other ankles between the tibialis anterior and the EHL. The leg is then placed in the leg holder and the rotation of the leg holder aligned parallel to the medial mortise. The calcaneus is fixed with two pins and the foot and lower leg secured to the leg holder with elastic wrap. The large fluoroscopic C-arm is guided into place and the anterior-posterior aiming sites are aligned confirming center location of the guide over the talus and the tibia. Then the lateral centering is accomplished with the C-arm in the lateral view. The AP view is then reobtained with proper centering and the plantar calcaneal heel pad is opened.  This routine technique requires simultaneous alignment of the talus with the tibia.   (For more severe cases I have aligned the talus only and then rotated the talus with the drill bit inserted to obtain tibial alignment.) Once that is achieved, the drill is passed from the plantar foot through the calcaneus, just anterior to the posterior facet, through the center of the talar body into the center of the tibial metaphysis, much like the guide pin for a retrograde ankle arthrodesis nail. While many argue that it is undesirable to violate the subtalar joint when performing TAA, the designers of the alignment guide maintain that if the device is applied appropriately, the drill safely negotiates the subtalar joint between the arterial anastamosis on the inferior talar neck and the posterior facet’s articulation with the inferior talus. No detriment has been observed thus far for this 6 mm hole.

A cannula is locked into position through the soft tissue and the calcaneus, talus and tibia drilled.  The cutting guide is now applied (its size predetermined on templated x-rays and confirmed intraoperatively) and verified with the C-arm. Alignment of the cutting guide on the drill is accomplished under fluoroscopy and the guide pinned into position. The antirotation drill is used to create a hole in the tibia.  Then the tibia and talus are cut through the saw guide. The saw guide is removed and the bone extracted. The tibia is reamed by applying the reamer onto the reaming rod inserted up through hole previously drilled in the calcaneus and talus. The ankle is then plantar flexed and the hole for the talar stem drilled. Then the cone portion of the prosthesis with one attached cylinder is inserted into the tibia followed by one additional cylinder, then the cylindrical base. The Morse taper tibial component is then tamped into place and the whole prosthesis driven into the tibia.  Next, the talar component is slid into place with the 10mm stem attached. If the longer 14 mm stem is chosen, it is inserted first (same for even longer stems, not yet FDA approved).  Then the talar component is inserted over the top of this stem and locked onto the Morse taper design. Finally, the polyethylene component is inserted and impacted into place. The wound is closed in layers.

Primary modular intramedullary ankle replacement is relatively straightforward. However, malalignment in the form of varus or valgus makes it more difficult to insert the INBONE when it exceeds 10 degrees in either direction and is especially problematic when it is over 15 degrees. However, newer techniques make this possible. For example, with varus malalignment, the use of a complete medial deltoid ligament “peel” combined with the use of lamina spreaders medially to tension the remaining lateral ligaments had led to expanding use of the modular intramedullary TAA for these deformities.   Similarly, lamina spreaders may also be used to align valgus deformities by placing tension laterally and distracting and realigning the ankle before making bone cuts. The surgeon must be prepared in the end to achieve bony alignment with calcaneal and sliding osteotomies, subtalar and TN fusions, Achilles tendon releases or gastrocnemius recessions, ligament reconstructions and even tendon transfers.

Significant bone loss has previously been a contraindication for ankle replacements.  However, the modular intramedullary ankle, by allowing an extended intramedulary stem gives the surgeon the ability to get good stability even with significant bone loss. Once the stem is in, the remaining defects can be bone grafted. Similarly, a flat top cut on the talus with the use of stems which vary in length, can be used to gain as much purchase on the talus as necessary. This is particularly valuable in cases of avascular necrosis where you want living bone to be in contact with the prosthesis.

Previously for tibial malunions, it has been recommended that realignment procedures be done as a staged procedure. However, modularity of the intramedullary tibial stem allows the surgeon to do a simultaneous supramalleolar osteotomy, temporarily hold it with K-wires and/or a plate and then use the intramedulary portion of the tibial stem to fixate it.

For many of these same reasons, the modular intramedullary ankle system is ideally suited to revise failed ankle replacements.  After prophylactic screw fixation has been inserted in the malleoli, existing loose ankles can be removed and well fixed ankle components can be sawed away from ongrowth bone. Then, by resecting minimal bone, again with the use of the lamina spreaders tensioning the soft tissue, a revision ankle can be inserted much like a primary ankle.

Finally, painful ankle fusions can also be taken down and replaced with the modular prosthesis. Of course it helps to have the fibula retained but takedowns have also involved those cases in which the fibula has been removed. Once more, prophylactic screws are recommended in the malleoli because this unstressed bone is weak and could lead to fracture. Placing the cutting jigs on the ankle without recutting the joint line has worked well if the ankle has been fused in a correct position. Afterwards the gutters are opened to once more allow freedom of motion.  If the ankle was fused in malposition, it is first necessary to recreate the ankle joint to allow orthogonal bone cuts.

These newer ankle systems will potentially allow all patients, regardless of deformity, to have an ankle replacement if no other contraindications exist.

Dr. DeOrio is an Associate Professor of Surgery specializing in Orthopaedic Surgery at the Duke University School of Medicine.  His special interests are lower extremity reconstruction, especially total ankle replacements and all other procedures involving the hind foot, midfoot, and forefoot deformities.

How Urgent are Open Fractures?

Dahners photo

Dr. Laurence Dahners

by Laurence E. Dahners, M.D.

A relatively new factor to consider in the treatment of trauma victims with open fractures is the fact that the data do not support the concept that open fractures are “emergencies requiring surgical debridement within six hours.” Initial studies were in pediatric open fracture but recently papers regarding infection rates in adults have been published as well. None of these studies has shown a statistically significant difference in infection rates in fractures debrided in less than six hours as compared to those debrided between six and twenty-four hours. The “trends” (non statistical differences) lean toward higher infection rates in those debrided in the first six hours! It does make a huge difference how soon the antibiotics are started so this remains very important. It is difficult to rationalize why early debridement would not lower infection rates but I hypothesize that it may be easier to differentiate necrotic from viable tissue when the debridement is carried out after six hours. In any case I now perform debridement during the daylight hours.

Dr. Dahners is a Professor of Orthopaedic Surgery at the UNC School of Medicine in Chapel Hill, NC, USA.  His clinical focus is on trauma and his research interests are in ligament physiology, ligament healing, ligament growth and contracture, and bone healing and the biomechanics of internal fixation.  You can see his “Pearls of Orthopaedics” on OrthopaedicList.com.

National Nurses Week

OR nurse

The Backbone of the OR

by James D. Hundley, MD

May 6 – 10, 2013 is National Nurses Week.  Please join the OrthopaedicLIST.com team in celebrating them for their extraordinary efforts.

My exposure has primarily been in the operating room, the PACU, and the wards where they do what is necessary to help patients recover.  Surgeons are generally very good at what they do.  Without nurses, however, we would be lost.

OR nurses prepare the patient, the operating room, the instruments, and help us do what we have set out to do.  If we didn’t have them to do that, we may be able to do one or two cases a day and probably not nearly as well.  Above that, they are typically the most compassionate of caregivers in the OR and their goals are in line with ours:  to do everything we can to help patients do better.

After surgery, nurses take care of patients in the PACU, a time of high risk as they awake from anesthesia.  Because of their skills and competence, we can compartmentalize our thinking and temporarily forget about the patient on whom we have just operated so that we can concentrate on the next.

Then patients go to the nursing floors.  Again, we depend heavily on them to do the right things and they aspire to do the same.  Their training, competence, attention, and compassion make the difference.  We can’t be there all of the time.  There are always nurses there and they know what to do.

Here’s hoping that you fellow surgeons will thank every nurse you see every day, especially this coming week.  As for your nurses, we thank you and hope that you’ll give yourselves a pat on the back, even if we can’t reach out and personally do so to every one of you.

Dr. Hundley is a retired orthopaedic surgeon and a Founder and the President of OrthopaedicLIST.com.

 

 

The Hensler Bone Press

Lumbar Lam Photo Cropped 20121231

Bone Block Formed from Graft Taken During Surgery

by Sean Hensler, PA-C (Neurosurgery) and Thomas Melin, MD (Neurosurgeon)

The Hensler Bone Press launched in the United States and in select countries internationally on December 18, 2012. It is a Class 2, 510K exempt device, FDA-approved for use. European launch is expected in March of 2013 following CE certification.

During the course of many operative procedures, bone is removed with the use of high speed drills. The bone removed with this technique is usually discarded. Unfortunately, this discarded bone is an excellent source of autologous bone graft for fusion procedures — if separated from blood and other tissues. The Hensler Bone Press (HBP) is a new, innovative device proven to maximize the collection and separation of this previously discarded material to yield high quality autologous bone graft. This device produces compressed, viable autologous bone which is immediately available for use. Many orthopedic, neurosurgical, maxillofacial and podiatry cases involve bone fusion where bone grafting is mandatory. Though many options for bone graft exist, autologous bone graft is universally accepted as the “gold standard”. All other options (synthetic and biologic) attempt to duplicate the characteristics of autologous bone but none has achieved all of these characteristics. This fact, coupled with the high cost of synthetic and biologic grafting options, renders them inferior to autologous bone graft. Though this device may not completely eliminate the need for synthetics or biologics, it will significantly diminish the use of these products. In summary, the HBP is an easy to learn, cost effective device proven to yield high quality autologous bone graft, which will decrease, if not eliminate, the need for synthetic and biologic options.

Founded in May 2011, Hensler Surgical Products, LLC is a Wilmington, NC-based medical device company dedicated to finding and developing innovative products that help to cut costs within health care. Friends and colleagues, Sean Hensler, a Neurosurgical Physician Assistant, and Dr. Thomas Melin, Neurosurgeon, formed Hensler Surgical Products, as a way to conceive, develop and introduce leading surgical innovations into the medical field. Hensler Surgical’s first product to market is the Hensler Bone Press, an innovative 2 stage device, designed to both collect and separate blood from valuable autologous bone generated by the high speed drill during surgical bone fusion grafting procedures while not interrupting the flow of the case.

Implant Identification, A Needed Service

by James D. Hundley, MD

Ross

Total Knee Prosthesis,
Model and Manufacturer Unidentified

From time to time I have been confronted with an implant that I did not recognize and could not find out what it was. Who hasn’t seen or heard of a bent femoral rod from trauma? If you haven’t, you likely will. Another example was an intramedullary rod that had been in a femur for thirty years and had to be removed for a total knee replacement. There are knee and hip prostheses that had been implanted at “Elsewhere General” and needed to be revised.
When I looked for a source that listed implants, I couldn’t find it. That’s when OrthopaedicList.com was conceived. That has proved to be immensely popular and useful for finding sources of implants, but we needed more. You still had to know what you were looking for. The next stage of evolution was “Implant Identification”.
As orthopaedic surgeons and operating room nurses know only too well, removing implants can be tricky and is not as easy to do as the x-ray might “suggest”. Various rods have a variety of cap screws, removal threads, locking screws, etc. You must have compatible instruments. If you are revising a total joint replacement implant and don’t need to revise all components, it is essential to know the brand and model of the device. Thus, you can match compatible components and preserve that which seems better left in place than removed.
Naturally it’s better to get the operative notes from the original surgery, but too often they don’t describe the implants. The best source I’ve seen are the implant package labels that the OR nurse affixes to the operating room record, but they are not always available.
At the suggestion of an orthopaedic professor, we started collecting x-ray images of identified implants on OrthopaedicList.com a few years ago. Since this is something that will always be evolving and since we wish to provide free access to our colleagues all over the world, we chose the Internet as our platform. Our library of implants has grown but needs to grow more. To do so, we need your help. Why would you wish to go to the trouble?
1. As time passes, more and more devices will be implanted in younger patients. Many will live into old age. When the time comes to do something, records may be unavailable, the surgeon may no longer be in practice, the surgeons and product representatives who may recognize these implants will be gone, and so on. By going to our library of X-Rays, you at least have a chance of figuring it out.
2. Please remember that what is familiar to you in your time and locale may very well be unfamiliar to someone else in another place or time. Thus, we are not just looking for what you consider uncommon, but we’re looking for what you implant in your everyday practice.
3. Some implant companies have their own library of images of their implants, but they are predominantly specific to their implants and not necessarily available to us.
4. Privacy rules are making it harder to obtain records, even with signed releases from our patients. I know about that from experience.
5. Our population is aging and people move around. There will be more and more people with implants. A growing number will need second surgeries in places different from the original hospitals.
6. The educational benefit has been an unanticipated bonus. Nursing and technical schools use our images to train their students. Medical schools in some countries do the same. At least one large orthopaedic manufacturer uses our service to train their new representatives. Furthermore, surgeons can send their patients to the site to see what various implants look like, including some cases that they have performed.
7. Those who give presentations need illustrations for their slides. You/they can copy the images from “Implant Identification” for those presentations.
8. We will make a donation to the Orthopaedic Research and Education Foundation in honor of those who submit images of x-rays.
9. You can post “unknowns” yourself in hope that our colleagues will help you identify your inherited, troublesome implants.

So, how does one submit an x-ray? Go to www.orthopaediclist.com and “roll over” “Implant Identification” on navigation bar near the top of the page. Click on “Submit an X-Ray”. The rest should be easy. If you have problems, please contact us at info@orthopaediclist.com.
Oh, how about patient privacy? When you submit images just crop out information that may identify the patient.
Thanks for your help. We’re all in this together for the benefit of our patients.

Dr. Hundley is a retired orthopaedic surgeon with forty years of experience. He is the president and a founder of OrthopaedicList.com.

Regaining Shoulder Range of Motion

by James D. Hundley, MD

Way back in 1968 during my first year of orthopaedic residency at the UNC Hospitals, Dr. Charles Neer, a famous shoulder surgeon, was our visiting professor. We learned a lot from Dr. Neer but the idea that stuck with me forever was his simple technique for regaining shoulder range of motion following surgery.
Dr. Frank Wilson, our training chief, was very graphic with his description of the shoulder capsule as being analogous to the leaves of an accordion. You had to tease them apart bit by bit. Except in rare cases, he frowned on manipulation under anesthesia.
Keep in mind that this is about regaining functional use of the shoulder in average people after a fracture or other injury and surgery. It is not about regaining strength other than in daily use of the limb and it’s certainly not about the definitive rehabilitation of athletes.
Naturally I must insert a disclaimer: I am not your treating physician. I am simply telling you what has worked for my patients for many years. Your treating physician is the one you should listen to primarily. Consider these ideas as supplementary or complimentary to what you’ve been told.

Here are some ideas to keep in mind:

1. Neer
a. The most useful positions of the shoulder find the hands in front of the body so if you can reach up in front enough to get to a cabinet above eye level and reach down to your lap, you can do most of what you want to do.
b. A simple way to accomplish this is to grasp your palms together and interlock your fingers. Straighten the elbows. Then use the normal arm to lift the hurt one. It works better if you lie supine since once you get to 90 deg. of forward flexion, gravity will assist you rather than fight you.

2. Wilson
a. Steady, almost constant, gentle stretching is needed, is generally safe, and can be very effective.
b. You need to move your shoulder often, not just once a day or so when a therapist is there to help you.
c. Manipulation under anesthesia seems fast but carries the risk of muscle and tendon ruptures as well as fracture. Furthermore, after a manipulation there is a tendency to quickly return to the pre-manipulation contractures.

3. Hundley
a. Passive range of motion precedes active range of motion. “Passive range of motion” means that something moves the affected limb other than the muscles of that limb. In these techniques you are using your good arm to move your bad one. “Active range of motion” may be contraindicated (i.e. should not be done) following some operations (rotator cuff repair for example) and fractures. Listen to your surgeon about when you can start active motion. Unless you regain passive range of motion, there is no chance of regaining active range of motion.
b. Flexion to get the arm overhead also helps with external rotation. Concentrate on flexion and don’t worry much about external rotation. It will follow.
c. It really helps to lie supine to use gravity when using the Neer technique. Otherwise, “gravity uses you”.
d. If you will prop your arm away from your body (pillows or arm rest or arm over the back of a sofa when sitting, elbow on a table or desk), you can change your starting point from down by the side to a better place. That gives you a head start and helps tease those sticky layers of capsule apart.
e. Find ways to stretch your arm forward and upward. Reach up to a tree limb, bar, door jamb, whatever it takes, and hold on to it for as long as possible.
f. Internal rotation is another matter. You have to make that happen. The best way is to reach the bad arm as far behind your back as you can and grasp the wrist of the bad arm with the hand of your good arm. Initially it will be just pulling to get it behind your body. Ultimately you need to start lifting the hand up the back until you get it as high as the hand of the good one will go.
g. Physical Therapists are very important in the rehabilitation process. If you depend on them to do all of the work, however, you are missing many opportunities to help yourself do better. They can treat you once every day or two. You need to be moving your shoulder almost all of the time.
h. Finally, here’s something to keep in mind about healing and my concept of “cumulative pain”. The body is a remarkable organism and starts trying to heal things almost the instant it is injured. That includes surgery. Healing starts with bleeding followed by formation of scar tissue and so on. If you wait until the pain of injury/surgery has subsided before you do any serious movement of a joint, I think that there is a 100% chance of it scarring down and never moving well. Early motion is critical. Cumulative Pain: I’ve always told my patients that the pain of regaining motion in injured joints can be equated to the pain of walking barefooted across a bed of hot coals. If you go slowly, I believe that you will hurt longer than if you push through the pain and go faster. Thus, your ultimate pain burden will be less if you move on and get it over with. That’s not to say that you can regain your motion in a day, but you probably do need to regain it in two or three weeks. Once four to six weeks have passed, you have a big mountain to climb.

Summary
1. You can and need to help yourself regain motion in your shoulder after injury or surgery. Your therapist is important but cannot do it all for you.
2. If you are doing your own pulling, you may cause pain but you are unlikely to harm yourself.
3. Time is critical. You cannot wait weeks and weeks to regain substantial range of motion.
4. Forward flexion is the most important movement. Do this by grasping the hands together and lifting the good arm with the bad. This is easier when lying supine than when vertical.
5. Prop your arm away from your body as often, as far, and for as long as you can.
6. External rotation tends to improve along with forward flexion, so concentrate on forward flexion.
7. Internal rotation needs special attention. Regain that by pulling the wrist of the bad arm behind and then up the back with the good hand.
8. Check with your physician/surgeon before doing these exercises and do not begin lifting the bad arm with its own muscles without your surgeon’s approval.

Dr. Hundley is a retired orthopaedic surgeon and the president of OrthopaedicLIST.com.