Markus Knupp

Sports and Recreation Activity of Ankle Arthritis Patients Before and After Total Ankle Replacement

Background Total ankle replacement is a possible treatment for ankle arthritis; however, participation in sports after this procedure has not yet been analyzed. Hypotheses There is a significant increase of sports activity after total ankle replacement in patients with arthritis. There is a significant correlation between sports activity and American Orthopaedic Foot and Ankle Society hindfoot score in patients after total ankle replacement. Study Design Case series; Level of evidence, 4. Methods A clinical evaluation was performed preoperatively and at follow-up after total ankle replacement in 147 patients (152 ankles) with ankle arthritis (mean age, 59.6 years; range, 28-86 years). Ankle arthritis origin, patient satisfaction, range of motion, American Orthopaedic Foot and Ankle Society hindfoot score, radiologic assessment, and rate, level, and type of sports activity were documented at both evaluations. The mean follow-up was 2.8 years (range, 2-4 years). Results Preoperative diagnosis was posttraumatic osteoarthritis in 115 cases (76%). At total ankle replacement follow-up, excellent and good outcomes were reported in 126 cases (83%); 105 cases (69%) were pain free. The mean range of motion preoperatively was 21° (range, 0°-45°); after total ankle replacement, it was 35° (range, 10°-55°; P < .05). The preoperative American Orthopaedic Foot and Ankle Society score was 36 points; after total ankle replacement, it was 84 points (P < .001). Before surgery, 36% of the patients were active in sports; after surgery, this percentage rose to 56% (P < .001). After total ankle replacement, sports-active patients showed a significantly higher hindfoot score than did patients not active in sports: 88 versus 79 points (P < .001). The 3 most frequent sports activities were hiking, biking, and swimming. Conclusion There was a significant increase of sports activity by treating ankle arthritis patients with total ankle replacement. Sports-active total ankle replacement patients showed better functional results than did inactive ones.

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.

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.

Cartilage lesions and the development of osteoarthritis after internal fixation of ankle fractures : a prospective study

BACKGROUND The role of the location and severity of the initial cartilage lesions associated with an ankle fracture in the development of posttraumatic osteoarthritis has not been established, to our knowledge. METHODS We performed a long-term follow-up study of a consecutive, prospectively included cohort of 288 ankle fractures that were treated operatively between June 1993 and November 1997. Arthroscopy had been performed in all cases in order to classify the extent and location of cartilage damage. One hundred and nine patients (47%) were available for follow-up after a mean of 12.9 years. The main outcome parameters were the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score for clinical evaluation and a modified Kannus osteoarthritis score for radiographic assessment of the development of posttraumatic osteoarthritis. RESULTS Cartilage damage anywhere in the ankle joint was associated with a suboptimal clinical outcome (odds ratio, 5.0 [95% confidence interval = 1.3 to 20.1]; p = 0.02) and with a suboptimal radiographic outcome (odds ratio = 3.4 [95% confidence interval = 1.0 to 11.2]; p = 0.04). An association was also found between the development of clinical signs of osteoarthritis and a deep lesion (>50% of the cartilage thickness) on the anterior aspect of the talus (odds ratio = 12.3 [95% confidence interval = 1.4 to 108.0]; p = 0.02) and a deep lesion on the lateral aspect of the talus (odds ratio = 5.4 [95% confidence interval = 1.2 to 23.5]; p = 0.02). A deep lesion on the medial malleolus was associated with the development of clinical signs of osteoarthritis (odds ratio = 5.2 [95% confidence interval = 1.9 to 14.6]; p < 0.01) and radiographic signs of osteoarthritis (odds ratio = 2.9 [95% confidence interval = 1.1 to 7.9]; p = 0.03) of osteoarthritis. There was no significant correlation between cartilage lesions on the fibula and the long-term outcome. CONCLUSIONS Our findings show that initial cartilage damage seen arthroscopically following an ankle fracture is an independent predictor of the development of posttraumatic osteoarthritis. Specifically, lesions on the anterior and lateral aspects of the talus and on the medial malleolus correlate with an unfavorable clinical outcome.

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

Effect of supramalleolar varus and valgus deformities on the tibiotalar joint: a cadaveric study

Background: Distal tibia coronal plane malalignment predisposes the ankle joint to asymmetric load. The purpose of this cadaveric study was to quantify changes in pressure and force transfer in an ankle with a supramalleolar deformity. Materials and Methods: Seventeen cadaveric lower legs were loaded with 700 N after creating supramalleolar varus and valgus deformities. The fibula was left intact in 11 specimens and osteotomized in six. Tekscan© sensors were used to measure the tibiotalar pressure characteristics. Results: In isolated supramalleolar deformity, the center of force and peak pressure moved in an anteromedial direction for valgus and posterolateral direction for varus deformities. The change was in an anteromedial direction for varus and in a posterolateral direction for valgus deformities in specimens with an osteotomized fibula. Conclusion: Two essentially different groups of varus and valgus deformities of the ankle joint need to be distinguished. The first group is an isolated frontal plane deformity and the second group is a frontal plane deformity with associated incon-gruency of the ankle mortise. Clinical Relevance: Our findings underline the complexity of asymmetric osteoarthritis of the ankle joint. 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.

Realignment Surgery for Valgus Ankle Osteoarthritis

ObjectiveImprovement of joint congruence, reduction of pain, slowdown of osteoarthritis progression, and prevention or delay of total ankle arthroplasty or ankle fusion.IndicationsActive patients with lateral valgus ankle joint degeneration.ContraindicationsPatients in poor general condition.Inability to adhere to postoperative non-weight-bearing rehabilitation.Distinct cartilage degeneration of more than half of tibiotalar joint surface.Systemic joint disease.Insufficiency of the deltoid ligament with tibiotalar subluxation malalignment.Surgical TechniqueDepending on stage of deformity:Stage I – collapse of the lateral tibia plafond and/or lateral malleolar gutter with subsequent valgus ankle arthritis: medial closing-wedge osteotomy of the distal tibia. Derotation- lengthening osteotomy in case of fibula malunion.Stage II – excessive calcaneus valgus: add medial sliding calcaneus osteotomy.Stage III – forefoot-induced hindfoot valgus (flatfoot deformity with forefoot abduction): add repair/augmentation of the posterior tibial tendon, superficial delta and spring ligaments; gastrocnemius/triceps release; flexion osteotomy of the first cuneiform or metatarsal bone or fusion of the first tarsometatarsal joint.Postoperative ManagementContinuous active and passive range of motion starting at the 2nd postoperative day. Removable short leg cast during nights. Partial weight bearing for 6–8 weeks until osseous healing has occurred, followed by gradual return to full weight bearing and activity.Results14 patients with stage I, three with stage II, and five with stage III valgus ankle osteoarthritis were treated. In two cases realignment surgery failed and progressive painful arthritis was treated by arthroplasty. The other 20 patients improved at an average follow-up of 4.5 years (range 3–6.5 years). Eight patients (41%) were free of pain. Tibiotalar arthritis and alignment (Takakura Score) improved significantly and correlated with significant improvement of pain (visual analog scale) and function (American Orthopaedic Foot and Ankle Society Score).ZusammenfassungOperationszielVerbesserte Gelenkkongruenz, Schmerzreduktion, Aufhalten des Arthroseprozesses und zeitliches Hinausschieben von Arthroplastik oder Versteifung des oberen Sprunggelenks (OSG).IndikationenAktive Patienten mit Valgusfehlstellung und lateraler Arthrose im OSG.KontraindikationenPatienten in schlechtem Allgemeinzustand.Unfähigkeit, das postoperative Rehabilitationsprogramm mit Entlastung durchzuführen.Fortgeschrittene Arthrose mit Degeneration von mehr als der Hälfte der tibiotalaren Gelenkfläche.Systemische GelenkerkrankungInsuffizienz des gesamten Ligamentum deltoideum mit tibiotalarer Subluxation.OperationstechnikIn Abhängigkeit vom Stadium der Deformität:Stadium I – Kollaps des lateralen Pilon tibiale und/oder des fibulotalaren Malleolargelenks mit konsekutiver Valgusarthrose: Medial zuklappende Osteotomie der distalen Tibia. Fibulaosteotomie zur Derotation und Verlängerung bei Pseudarthrose.Stadium II – Valgusfehlstellung der Ferse: Zusätzliche Durchführung einer medialen Verschiebeosteotomie des Tuber calcanei.Stadium III – Valgusfehlstellung der Ferse, induziert durch eine Vorfußabduktion bei Pes planovalgus: Zusätzliche Durchführung einer Naht/Augmentation der Tibialis-posterior-Sehne, des vorderen Ligamentum deltoideum und des Ligamentum calcaneonavicular, einer Verlängerung des Musculus gastrocnemius/Musculus triceps, einer Flexionsosteotomie des Os cuneiforme mediale/Metatarsale I oder einer Versteifung des ersten tarsometatarsalen Gelenks.WeiterbehandlungAktive und passive Bewegungsübungen im OSG ab dem 2. postoperativen Tag. Entfernbarer Unterschenkelgipsverband. Sohlenkontakt für 6–8 Wochen postoperativ bis zur Knochenheilung. Anschließend schrittweiser Übergang zur Vollbelastung.Ergebnisse14 Patienten im Stadium I, drei im Stadium II und fünf im Stadium III wurden Korrekturoperationen bei Valgusarthrose im OSG unterzogen. In zwei Fällen kam es zur Ausbildung einer progressiven schmerzhaften OSG-Arthrose, welche mittels OSG-Prothese therapiert wurde. Die übrigen 20 Patienten zeigten nach einer mittleren Nachkontrollzeit von 4,5 Jahren (3–6,5 Jahre) eine Verbesserung der Studienvariablen. Acht Patienten (41%) waren schmerzfrei. Tibiotalare Arthrose und Alignment (Takakura-Score) verbesserten sich signifikant und korrelierten mit der Verbesserung der Schmerzen (visuelle Analogskala) und der Funktion (Score der American Orthopaedic Foot and Ankle Society).