P. Maldague

Medium term follow-up of the AES ankle prosthesis: High rate of asymptomatic osteolysis☆

BACKGROUND The AES (Ankle Evolutive System) is a cobalt-chromium three-component ankle prosthesis with a hydroxyapatite coating, similar to the Buechel-Pappas ankle prosthesis, but with some modifications. Our objective was to assess its medium term follow-up results as well as its complications. METHODS 21 patients (mean age of 57.6 years) were operated by a total ankle arthroplasty (TAA), using the AES implant, according to the standard technique. Only 18 patients were included. The other three patients were excluded from the study: two had been revised for avascular talar necrosis and one patient was happy with her outcome but could not present for logistic reasons at the last follow-up. Indications for surgery included posttraumatic osteoarthritis, primary osteoarthritis, hemochromatosis, rheumatic arthritis and osteoarthritis as a sequel of ankle instability. All patients were analyzed clinically and radiologically. Special attention was given to the presence or not of areas of osteolysis around the implants as well on conventional radiography as on CT-scan imaging, according to a specific protocol. RESULTS The mean follow-up was 39.4 months. Average American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score improved from 52.2 preoperatively to 86.6 postoperatively. No intra-operative complications or early complications have been noted. Delayed complications were the following: one valgus malalignment, one recurrent painful anterior heterotrophic bone formation. Above all, we noted on conventional X-ray the presence of osteolysis in 77% (14) of our patients, with a size of 0.5-1cm or greater on conventional X-ray. The most vulnerable area seemed to be the posterior tibial plafond. The four remaining patients did not show any cyst formation on X-ray but did also, just as the other 14 patients, on the CT-scan. CT-scan, on the contrary, found more osteolysis in the body of the talus, underneath the implant, an area masked on conventional X-ray. Only one patient was revised with allograft bone filling of a symptomatic osteolysis, without the need for implant removal. CONCLUSIONS This retrospective study shows a high frequency of delayed appearance of osteolysis (77%) in 18 AES total ankle arthroplasties. Fortunately at this moment and considering one revision, this considerable amount of asymptomatic osteolysis could not warrant a durable uncomplicated outcome.

Arthrodesis After Failed Total Ankle Replacement.

Background: The literature on salvage procedures for failed total ankle replacement (TAR) is sparse. We report a series of 17 patients who had a failed TAR converted to a tibiotalar or a tibiotalocalcaneal arthrodesis. Methods: Between 2003 and 2012, a total of 17 patients with a failed TAR underwent an arthrodesis. All patients were followed on a regular basis through chart review, clinical examination and radiological evaluation. The following variables were analyzed: pre- and postoperative Meary angle, cause of failure, method of fixation, type of graft, time to union, complications, and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) score. The average follow-up was 30.1 months. The average period from the original arthroplasty to the arthrodesis was 49.8 months. Results: Thirteen of the 17 ankles were considered radiographically healed after the first attempt in an average time of 3.7 months and 3 after repeat arthrodesis. Bone grafts were used in 16 patients. The median postoperative AOFAS score was 74.5. The mean Meary angle of the hindfoot was 5 degrees of valgus. Conclusion: Tibiotalar and tibiotalocalcaneal arthrodeses were effective salvage procedures for failed TAR. Massive cancellous allografts were a good alternative to compensate for the large bone defect after removal of the prosthesis and to preserve the leg length. Level of Evidence: Level IV, retrospective case series.

Technique and early experience with posterior arthroscopic tibiotalocalcaneal arthrodesis.

Tibiotalocalcaneal arthrodesis is indicated for pain relief in patients with combined arthritis of the ankle and subtalar joint. An arthroscopic posterior approach was designed to improve upon traditional methods by using a minimally invasive technique. The technique involves prone positioning of the patient, one anterolateral and two posterolateral portals, and arthroscopic debridement of both the tibiotalar and posterior talocalcaneal joint. Stabilisation is obtained with a retrograde intramedullary nail, with static interlocking. This article presents illustrative cases and discusses some of the technical advantages and disadvantages over conventional open surgery. For surgeons familiar with posterior ankle or subtalar arthroscopy, this minimally invasive debridement and nailing appears to offer superior exposure, high patient satisfaction and lower postoperative morbidity than traditional methods; fusion is encouraged by preserving the medullary reaming material at the site of the fusion.

Intermediate-term Results of Mobile-bearing Total Ankle Replacement

Background: The literature analyzing total ankle replacement (TAR) results should be critically interpreted because studies made by the design surgeons are potentially subject to bias. European nondesigner surgeon studies reviewing the HINTEGRA TAR system are scarce in the literature. The present study is a European nondesigner surgeon study reviewing a consecutive series of 50 HINTEGRA TAR systems with a minimum follow-up of 2 years, focusing on clinical and radiographic outcomes. Methods: Fifty primary TAR procedures were performed between February 2008 and January 2012 by a single surgeon. Every patient underwent a standardized clinical and radiographic follow-up at 6 weeks, 3 and 6 months, and 1 year postoperatively and annually thereafter. The mean time to final follow-up was 45 months. Results: The mean American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale score significantly increased from 43.5 preoperatively to 83.8 postoperatively. Clinical range of motion of the ankle also improved from 23.3 degrees preoperatively to 28.3 degrees postoperatively. In 70% of the TAR procedures, the talar component was positioned anteriorly with respect to the tibial axis. Radiological evidence of osteolysis was identified in 24 ankles. The failure rate in the present series was 10%, which was defined as having major revision surgery within 4 years. Conclusion: The survival of the first 50 HINTEGRA TAR systems in this series was satisfactory from clinical and radiological points of view. However, the incidence of asymptomatic periprosthetic osteolytic lesions was quite high (24 ankles). Level of Evidence: Level IV, retrospective case series.

Plantar pressure relief using a forefoot offloading shoe.

AIM To assess the effectiveness of the Barouk(®) second-generation postoperative forefoot relief shoes during appropriate use of the shoe on healthy subjects. MATERIALS AND METHODS A convenience sample of 35 volunteer subjects (17 women, 18 men) was recruited to participate in this study. Dynamic foot loading was evaluated with inshoe plantar pressure measurements. Subjects were asked to walk two trials at a self-selected speed: (a) in their mass-produced shoes to assess baseline pressure values, defined as 100% and (b) with the Barouk(®) postoperative shoe on the right foot and their own shoe on the left side. Data analysis was tested for statistical differences with paired Students t-tests (with p<0.05 as a significance level). RESULTS The Barouk(®) second-generation postoperative forefoot relief shoes relieved forefoot pressure in all trials. For all 35 volunteers, there was a 79-96% mean peak pressure reduction (p<0.001) of the forefoot except for the fifth metatarsal head during appropriate use of the postoperative shoe. In contrast to the results for the forefoot, a significant increase of the peak pressure values was observed in the heel region. Similar findings were observed for the pressure-time integral values. CONCLUSION The data of our study provide evidence that the second-generation Barouk(®) shoe relieve pressure of the forefoot with appropriate use.

Tarsal tunnel syndrome and flexor hallucis longus tendon hypertrophy

Tarsal tunnel syndrome (TTS) defines an entrapment neuropathy of the posterior tibial nerve or one of its branches, within the tarsal tunnel. Numerous etiologies have been described explaining this entrapment, including trauma, space-occupying lesions, foot deformities, etc. We present an unreported cause of a space-occupying lesion in the etiology of TTS, namely the combination of a hypertrophic long distally extended muscle belly of the flexor hallucis longus and repetitive ankle motion. Surgical debulking of the muscle belly in the posterior ankle compartment resolved all symptoms.

Anatomical characteristics of the flexor digitorum accessorius longus muscle and their relevance to tarsal tunnel syndrome a systematic review.

BACKGROUND Clinical and cadaver studies have reported that supernumerary muscles could be the etiology of a variety of pathologic disorders, such as posterior impingement syndrome, tarsal tunnel syndrome (TTS), and flexor hallucis longus tenosynovitis. We describe a unique variant of the flexor digitorum accessorius longus (FDAL) muscle as an apparent cause of TTS, functioning as an independent flexor of the second toe, which has not been described in the literature. In addition to this case report, a systematic review was performed of TTS caused by the FDAL muscle. METHODS A targeted search of PubMed, the Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature, and Web of Science identified full-text papers that fulfilled the inclusion and exclusion criteria. RESULTS Twenty-nine papers were identified for inclusion in the systematic review: 12 clinical papers of TTS caused by the FDAL muscle and 17 cadaver-based papers. CONCLUSIONS Clinicians often do not include the FDAL muscle in the differential diagnosis of TTS. This literature review suggests that the FDAL is an important muscle in terms of its functional and clinical significance. Knowledge of this muscle, its anatomical location and variations, and its magnetic resonance imaging characteristics may help clinicians make an accurate differential diagnosis.

Arthroscopic Debridement After Total Ankle Arthroplasty

Background: Residual pain due to impingement after ankle arthroplasty can be addressed with arthroscopic debridement. Literature focusing on the effectiveness of arthroscopic debridement after total ankle arthroplasty (TAA) is scarce. The authors report a case series of 12 patients complaining of anterior or posterior impingement pain, 11 of which were in the absence of malalignment which were treated by arthroscopy. Methods: Of the 106 TAAs performed between 2003 and 2012, a total of 12 subjects reported postoperative pain resulting from anterior or anteromedial impingement, medial and/or lateral gutter impingement, posterior impingement, and/or ankylosis. All patients were reviewed on a regular basis through chart review, clinical examination, and radiologic evaluation. The average time to final follow-up was 58.8 months. The average period from the original TAA to the arthroscopic debridement was 38.2 months. Results: The median AOFAS hindfoot score was significantly (P < .05) improved from 64.6 preoperatively to 73.5 postoperatively. Eight subjects reported good pain relief after the arthroscopic debridement, and partial pain relief was reported by 4 subjects. Three patients with painful ankylosis had no improvement in the total range of motion of the TAA implant after the arthroscopic debridement. Conclusion: The results suggest that arthroscopic debridement in patients with residual pain due to impingement syndromes after TAA was effective in 8 of the 12 cases at 2 years’ follow-up. However, the results suggest that arthroscopic debridement in the presence of painful ankylosis associated with or without impingement syndromes results only in partial pain relief and does not improve the range of motion. Level of Evidence: Level IV, case series.

Posterior Arthroscopic Subtalar Arthrodesis

Introduction Although subtalar joint arthrodesis may be achieved through open or arthroscopic approaches, we have found that posterior arthroscopic subtalar arthrodesis has technical advantages compared with other approaches. Step 1 Preoperative Assessment and Planning Clinically assess the foot and ankle with regard to remaining motion, previous scarring, and associated deformities, ensuring that no concomitant procedure will be needed in the supine position. Step 2 Positioning of the Patient Use spinal or general anesthesia. Step 3 Placement of the Posterolateral Portal Lateral to the Achilles Tendon Place the posterolateral portal lateral to the Achilles tendon at the level of the tip of the lateral malleolus, according to the original technique described by van Dijk et al. Step 4 Placement of the Posteromedial Portal Medial to the Achilles Tendon Place the posteromedial portal medial to the Achilles tendon at the level of the tip of the lateral malleolus. Step 5 Exposure of the Subtalar Joint by Removing the Fatty Tissue and Part of the Posterior Joint Capsule With the help of the shaver, look for the landmarks of the posterior arthroscopy, going from the posterolateral part of the subtalar joint toward the flexor hallucis longus tendon, which is medially located, while exposing the tibiotalar joint. Step 6 Debridement and Microfracturing of the Posterior Facet of the Subtalar Joint Sometimes an accessory portal, just anterior to the tip of the external malleolus, may be needed to achieve a distraction of the anterior part of the subtalar posterior facet. Step 7 Use of Bone Graft To perform this concomitant step, which generally is not necessary, use an arthroscopic forceps to insert a 5 by 20-mm autograft or allograft in the subtalar joint. Step 8 Fixation of the Subtalar Joint Using Two Cannulated Screws and Fluoroscopy Use two cannulated screws with a 7.3-mm diameter; we prefer stabilization screws to compression screws. Step 9 Additional Surgical Procedures Always clean out the posterior compartment of the ankle during the PASTA procedure, as is done during surgical treatment for posterior impingement syndrome, and note that both posterior impingement syndrome and subtalar degenerative changes may thereby be easily addressed through this procedure. Step 10 Postoperative Care A short posterior leg splint is worn for three to ten days, followed by another non-weight-bearing cast for another three weeks. Results Since the appearance of the original article, a total of forty-one unilateral subtalar joints in twenty-five men and sixteen women, seen between May 2007 and December 2012, with isolated subtalar arthritis or talocalcaneal coalition without any other major hindfoot arthritis were treated by posterior arthroscopic subtalar arthrodesis, and all subtalar joints except for two were considered radiographically fused at the first attempt after an average of 6.7 weeks (range, six to ten weeks).IndicationsContraindicationsPitfalls & Challenges.