Alexej Barg

Realignment surgery as alternative treatment of varus and valgus ankle osteoarthritis.

In patients with asymmetric (varus or valgus) ankle osteoarthritis, realignment surgery is an alternative treatment to fusion or total ankle replacement in selected cases. To determine whether realignment surgery in asymmetric ankle osteoarthritis relieved pain and improved function, we clinically and radiographically followed 35 consecutive patients with posttraumatic ankle osteoarthritis treated with lower leg and hindfoot realignment surgery. We further questioned if outcome correlated with achieved alignment. The average patient age was 43 years (range, 26-68 years). We used a standardized clinical and radiographic protocol. Besides distal tibial osteotomies, additional bony and soft tissue procedures were performed in 32 patients (91%). At mean followup of 5 years (range, 3-10.5 years), pain decreased by an average of 4 points on a visual analog scale; range of ankle motion increased by an average of 5°. Walking ability and the functional parts of the American Foot and Ankle Society score increased by an average of 10 and 21 points, respectively, and correlated with achieved reversal of tibiotalar tilt and the score of Takakura et al. Revision surgery was performed in 10 ankles (29%), of which three ankles (9%) were converted to total ankle replacement. We believe the data support realignment surgery for patients with asymmetric ankle osteoarthritis. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Tumor-derived matrix metalloproteinase-1 targets endothelial proteinase-activated receptor 1 promoting endothelial cell activation.

In the vascular system, circulating tumor cells interact with endothelial cells. Tumor-endothelial cross-talk transforms the intravascular milieu to a prothrombotic, proinflammatory, and cell-adhesive state called endothelial cell activation (ECA). In the present study, we analyze the potential of metastatic tumor-derived soluble factors to transform the vascular endothelium into a prothrombotic and proinflammatory activated state. Supernatant from cultured melanoma and colon cancer cells (A375, WM9, A7, and HT-29) induced an acute activation of macrovascular and microvascular endothelial cells (human umbilical vein endothelial cells and human dermal microvascular endothelial cells) as shown by intracellular calcium flux and secretion of von Willebrand factor and interleukin-8, all markers of acute ECA. This process was inhibited using specific proteinase-activated receptor 1 (PAR1) inhibitors (RWJ-58259 and SCH-79797), indicating a mediating role for endothelial thrombin receptors. Immunofluorescence, Western blot analysis, and collagenase activity assay of tumor cells and culture supernatant revealed the presence of matrix metalloproteinase-1 (MMP-1), a recently described activator of PAR1. Inhibition of MMP-1 in supernatant from cultured tumor cells significantly attenuated ECA. Additional studies using isolated human MMP-1 (5 nmol/L) proved the presence of a functional MMP-1/PAR1 axis in tumor-endothelial communication. These findings show a new pathway of tumor-endothelial cross-talk via an intravascular MMP1/PAR1 axis in microvascular and macrovascular endothelium. Inhibition of this cross-talk may be a powerful means to prevent tumor-induced ECA and thus thrombotic and inflammatory cell adhesion.

SPECT‐CT compared with conventional imaging modalities for the assessment of the varus and valgus malaligned hindfoot

The combined single‐photon emission computed tomography and conventional computed tomography (SPECT/CT) technique has increased the sensitivity and specificity of bone scans. We examined the value of using SPECT/CT for the assessment of coronal plane hindfoot deformities. Twenty‐seven patients with varus (11 patients) or valgus (16 patients) malalignment of the hindfoot were assessed using radiography, conventional CT, bone scintigraphy, and SPECT/CT. The amount of deformity, stage of osteoarthritis, and level of activation on bone scans and SPECT/CT were measured. Activation was assessed in 12 regions of interest. The stage of osteoarthritis seen on plain radiographs correlated significantly with the level of activation detected on bone scans (p < 0.05). No correlation was observed between the amount of deformation and activity, and between bone scan activation and signs of osteoarthritis on CT scans. The varus malaligned ankles showed higher radioisotope uptake in the medial areas, while the valgus malaligned ankles showed increased uptake in the lateral areas (p < 0.05). SPECT/CT may be a valuable tool for the assessment and staging of osteoarthritis. Our findings underline the adverse effects of coronal plane deformity of the hindfoot. In addition, results from this study provide useful information for future basic research on coronal plane deformity of the hindfoot and for determining appropriate surgical approaches.

Classification and Treatment of Supramalleolar Deformities

Background: Supramalleolar osteotomies are increasingly popular for addressing asymmetric arthritis of the ankle joint. Still, recommendations for the indication and the use of additional procedures remain arbitrary. We preoperatively grouped different types of asymmetric arthritis into several classes and assessed the usefulness of an algorithm based on these classifications for determining the choice of supramalleolar operative procedure and the risk factors for treatment failure. Methods: Ninety-two patients (94 ankles) were followed prospectively and assessed clinically and radiographically 43 months after a supramalleolar osteotomy for asymmetric arthritis of the ankle joint. Results: Significant improvement of the clinical scores was found. Postoperative reduction of radiological signs of arthritis was observed in mid-stage arthritis. Age and gender did not affect the outcome. Ten ankles failed to respond to the treatment and were converted to total ankle replacements or fused. Conclusions: Supramalleolar osteotomies can be effective for the treatment of early and midstage asymmetric arthritis of the ankle joint. However, certain subgroups have a tendency towards a worse outcome and may require additional surgery. Therefore preoperative distinction of different subgroups is helpful for determination of additional procedures. Level of Evidence: II, Prospective Comparative Study

The Scandinavian total ankle replacement: long-term, eleven to fifteen-year, survivorship analysis of the prosthesis in seventy-two consecutive patients.

BACKGROUND The objective of this study was to determine the long-term survivorship and clinical and radiographic results of the Scandinavian Total Ankle Replacement (STAR). METHODS From February 1996 to March 2000, seventy-seven ankles in seventy-two patients (thirty-seven female and thirty-five male patients, with an average age of fifty-six years) underwent total ankle replacement using the STAR prosthesis with a single coating of hydroxyapatite. Two patients were lost to follow-up, and twelve patients with thirteen ankle replacements died. The average duration of follow-up for the patients without revision was 12.4 years (range, 10.8 to 14.9 years). Sixty-two of the seventy-seven ankles were available for final follow-up. RESULTS Twenty-nine (38%) of the seventy-seven ankles had a revision of at least one of the metallic components. The probability of implant survival was 70.7% at ten years and 45.6% at fourteen years. The main reasons for revision were aseptic loosening, subsidence of the talar component, and progressive cyst formation. Polyethylene insert fractures were observed in eleven ankles. CONCLUSIONS While the midterm to short-term results for patients managed with the STAR prosthesis have been encouraging at 3.7 years, the long-term survivorship of the same cohort was considerably inferior. The subjective and clinical results of the patients with retained prostheses are generally good and comparable with results reported in the current literature.

Postoperative complications of posterior ankle and hindfoot arthroscopy.

BACKGROUND Posterior ankle and hindfoot arthroscopy, performed with use of posteromedial and posterolateral portals with the patient in the prone position, has been utilized for the treatment of various disorders. However, there is limited literature addressing the postoperative complications of this procedure. In this study, the postoperative complications in patients treated with posterior ankle and hindfoot arthroscopy were analyzed to determine the type, rate, and severity of complications. METHODS The study included 189 ankles in 186 patients (eighty-two male and 104 female; mean age, 37.1 ± 16.4 years). The minimum duration of follow-up was six months, and the mean was 17 ± 13 months. The most common preoperative intra-articular diagnoses were subtalar osteoarthritis (forty-six ankles), an osteochondral lesion of the talus (forty-two), posterior ankle impingement (thirty-four), ankle osteoarthritis (twenty), and subtalar coalition (five). The most common extra-articular diagnoses were painful os trigonum (forty-six), flexor hallucis longus tendinitis (thirty-two), and insertional Achilles tendinitis (five). RESULTS The most common intra-articular procedures were osteochondral lesion debridement (forty-four ankles), subtalar debridement (thirty-eight), subtalar fusion (thirty-three), ankle debridement (thirty), and partial talectomy (nine). The most common extra-articular procedures were os trigonum excision (forty-eight), tenolysis of the flexor hallucis longus tendon (thirty-eight), and endoscopic partial calcanectomy (five). Complications were noted following sixteen procedures (8.5%); four patients had plantar numbness, three had sural nerve dysesthesia, four had Achilles tendon tightness, two had complex regional pain syndrome, two had an infection, and one had a cyst at the posteromedial portal. One case of plantar numbness and one case of sural nerve dysesthesia failed to resolve. CONCLUSIONS Our experience demonstrated that posterior ankle and hindfoot arthroscopy can be performed with a low rate of major postoperative complications.

HINTEGRA Total Ankle Replacement: Survivorship Analysis in 684 Patients

BACKGROUND Total ankle replacement is increasingly recommended for patients with end-stage ankle osteoarthritis. We analyzed the survivorship of 722 arthroplasties performed with one type of three-component total ankle prosthesis. METHODS Seven hundred and seventy-nine primary total ankle arthroplasties (741 patients) were performed between May 2000 and July 2010 with use of the HINTEGRA three-component prosthesis. A logistic multiple regression model was used to identify independent risk factors for prosthesis failure in 684 patients (722 ankles). The mean time to final follow-up (and standard deviation) was 6.3 ± 2.9 years. RESULTS Seven hundred and twenty-two ankles (684 patients) were available for survivorship analysis at the latest follow-up. The overall survival rates were 94% and 84% after five and ten years, respectively. Sixty-one ankles had a revision arthroplasty (twenty-seven both components, thirteen the tibial component only, and fourteen the talar component only) or were converted to a fusion (seven ankles).There were no polyethylene failures. There were no amputations. The generation category of the prosthesis, the cause of ankle osteoarthritis, and the age of the patient were identified as independent risk factors for prosthesis failure. CONCLUSIONS The midterm survivorship of the HINTEGRA implant was comparable with that of other third-generation total ankle replacements.

The effect of three-component total ankle replacement malalignment on clinical outcome: pain relief and functional outcome in 317 consecutive patients.

BACKGROUND Total ankle replacement has become an increasingly popular treatment for patients with end-stage ankle osteoarthritis. The surgery is technically demanding and generally performed by only experienced foot and ankle surgeons. An important complication of total ankle replacement is malposition of the talar component. The biomechanical effect of malposition has been reported; however, the functional outcomes of patients with varying degrees of talar component malposition have not. The purpose of this study was to assess the influence of talar component malposition on postoperative pain relief and functional outcome. METHODS This retrospective cohort study included 317 total ankle replacements in 317 patients. The anteroposterior offset ratio was measured with use of lateral ankle radiographs made with the patient in a standing, weight-bearing position. Patients were classified into one of three groups: those with an anteroposterior offset ratio of 0 (127 ankles), those with a ratio of >0 (103 ankles), and those with a ratio of <0 (eighty-seven ankles). Postoperative pain relief was assessed with use of a visual analogue scale. Functional outcome was assessed with the American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score and measurement of ankle range of motion. The mean duration of follow-up (and standard deviation) was 53.2 ± 18.4 months (range, twenty-four to ninety-eight months). RESULTS The postoperative pain level in the group with an anteroposterior offset ratio of 0 was significantly lower than that for both the group with a ratio of >0 (p < 0.001) and the group with a ratio of <0 (p = 0.017). Also, the functional outcome, measured with use of the AOFAS hindfoot score, was significantly higher, and ankle motion was significantly greater, in the group with an anteroposterior offset ratio of 0 than in the group with a ratio of >0 (p = 0.003 and p < 0.001, respectively) and the group with a ratio of <0 (p = 0.007 and p = 0.080). CONCLUSIONS The anteroposterior offset ratio may be a useful predictor of outcome in patients with total ankle replacement with regard to both pain and function. LEVEL OF EVIDENCE Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Conversion of Painful Ankle Arthrodesis to Total Ankle Arthroplasty

BACKGROUND Pain following an ankle arthrodesis continues to be a challenging clinical problem. Recent reports on semiconstrained two-component ankle implants have demonstrated the feasibility of reversing a problematic ankle fusion and converting it to a total ankle arthroplasty. However, the failure rate is high. The objective of the present prospective study was to evaluate the intermediate-term outcome associated with the use of an unconstrained three-component ankle implant after taking down an ankle arthrodesis. METHODS Thirty painful ankles in twenty-eight patients (average age, 58.2 years) who were managed with takedown of a fusion and total ankle arthroplasty were followed for a minimum of thirty-six months (average, 55.6 months). The outcome was assessed on the basis of clinical and radiographic evaluations. RESULTS In twenty-nine ankles in twenty-seven patients, the American Orthopaedic Foot and Ankle Society hindfoot score increased from 34.1 preoperatively to 70.6 at the time of the latest follow-up. Twenty-four patients (82.7%) were satisfied with the results. While five ankles were completely pain-free, twenty-one ankles were moderately painful, and three remained painful. The average clinically measured range of motion of 24.3 degrees amounted to 55.1% of that of the contralateral, unaffected ankle. Radiographically, the tibial component was stable in all ankles but one. The talar component was found to have migrated in four ankles but was asymptomatic in two of them. One ankle had to be revised to a tibiocalcaneal arthrodesis because of persistent pain and loosening of the talar component. CONCLUSIONS For patients with pain at the site of a failed ankle arthrodesis, conversion to total ankle arthroplasty with the use of a three-component ankle implant is a viable treatment option that provides reliable intermediate-term results. Key factors for the success of this procedure may be the intrinsic coronal plane stability provided by the ankle implants and the use of wider talar implants.

Anterior double plating for rigid fixation of isolated tibiotalar arthrodesis.

Background: Arthrodesis is the most common procedure used to treat end-stage osteoarthritis of the ankle, particularly in patients with difficult conditions such as poor bone quality. While many techniques are available to fuse the ankle, current recommendations favor the use of internal fixation with screws and/or plates. Despite of progress, the complication rate remains a major concern. Non-union is one difficult problem especially with difficult bone conditions, particularly the loss of bone stock on the talar side. Therefore, fusion of the tibiotalar joint is often extended to the talocalcaneal joint to provide sufficient stability. To preserve the subtalar joint, an anterior double plate system for rigid fixation of isolated tibiotalar arthrodesis was developed. This is a preliminary report on the clinical and radiological outcome with this technique. Materials and Methods: Twenty-nine patients (15 men, 14 women; one ankle per patient) were treated from October 2006 to September 2007. We converted 16 ankles with osteoarthritis and difficult bone conditions, four non-united ankle arthrodeses, and nine failed total ankle replacements to an isolated tibiotalar arthrodesis using anterior double plating. If necessary, we used solid allograft to fill bony defects. Outcomes included bone union as assessed by radiographs, pain as indicated by the American Orthopaedic Foot and Ankle Society scores, and patient satisfaction. Results: Solid arthrodesis was achieved after an average of 12.3 (eight to 26) weeks in the 16 ankles without bone graft interposed between the tibia and talus, and 14.3 (range, 8 to 26) weeks in the 13 ankles with interpositional bone allograft. Radiographs showed that the position of arthrodesis obtained at the time of surgery did not change in any patient up to one year after surgery. The mean American Orthopaedic Foot and Ankle Society (AOFAS) Hindfoot Score increased from 37 (range, 20 to 63) preoperatively to 68 (range, 50 to 92) at the last followup. Twenty-seven patients (93%) were satisfied with their outcome and indicated they would have the operation again. No complications were noted. Conclusion: The anterior double plating system was shown be a reliable method to achieve solid isolated tibiotalar arthrodesis, even in ankles with difficult conditions such as loss of bone stock due to failed total ankle arthroplasty. Level of Evidence: IV, Retrospective Case Series