Intermediate-term Experience With the STAR Total Ankle in the United States.

BACKGROUND:: Limited intermediate and no real long-term follow-up data have been published for total ankle arthroplasty (TAA) in the United States. This is a report of clinical follow-up data of a prospective, consecutive cohort of patients who underwent TAA by a single surgeon from 1999 to 2013 with the Scandinavian Total Ankle Replacement (STAR) prosthesis. METHODS:: Patients undergoing TAA at a single US institution were enrolled into a prospective study. These patients were followed at regular intervals with history, physical examination, and radiographs; American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot Scale scores were obtained and recorded. Primary outcomes included implant survivability and functional outcomes scores. Secondary outcomes included perioperative complications such as periprosthetic or polyethylene fracture. Between 1999 and 2013, a total of 138 STAR TAAs were performed in 131 patients; 81 patients were female. The mean age at surgery was 61.5 ± 12.3 years (range, 30-88 years). The mean duration of follow-up for living patients who retained both initial components at final follow-up was 8.8±4.3 years (range 2-16.9 years). RESULTS:: The mean change in AOFAS Ankle-Hindfoot scores from preoperative to final follow-up was 36.0 ± 16.8 ( P < .0001). There were 21 (15.2%) implant failures that occurred at a mean 4.9 ± 4.5 years postoperation. Ten polyethylene components in 9 TAAs (6.5%) required replacement for fracture at an average 8.9 ± 3.3 years postoperatively. Fourteen patients died with their initial implants in place. CONCLUSION:: This cohort of patients with true intermediate follow-up after TAA with the STAR prosthesis had acceptable implant survival, maintenance of improved patient-reported outcome scores, and low major complication rates. LEVEL OF EVIDENCE:: Level IV, case series.

Salvage arthrodesis after failed ankle replacement: surgical decision making.

Fusion remains the primary technique to salvage the failed total ankle. Fusions present a daunting challenge because of the large bone defect left by the explanted arthroplasty components and the difficulty obtaining stable fixation. Limiting the fusion to the tibiotalar joint preserves the essential motion of the hindfoot. However, because of loss of talar bone stock, it is often necessary to include the subtalar joint in a tibiotalocalcaneal fusion. This article discusses how to determine whether an isolated ankle or ankle-hindfoot fusion is indicated and presents surgical techniques for filling the bone defect and achieving stable internal fixation.

Salvage of failed total ankle arthroplasty with fusion using structural allograft and internal fixation.

BACKGROUND: The current study presents our experience with conversion of failed TAA to fusion. MATERIALS AND METHODS: A retrospective review of all failed total ankles converted to fusion from 1999 to 2009 was performed at our institution. RESULTS: Twelve total ankles were converted to isolated ankle fusions (Group I) and 12 converted to ankle-hindfoot fusions (Group II). All isolated ankle fusions were stabilized with anterior plate and screws with one nonunion. Structural bone graft was used in ten of 12. Mean outcome scores using the AOFAS-Ankle/Hindfoot score and Maryland Foot Score improved from preoperative values of 43 ± 13 and 56.7 ± 14 to 67 ± 12 and 71.2 ± 16 postoperatively, respectively (p < 0.05). All Group II ankle-hindfoot fusion patients were fixed using either anterior plate and screws, intramedullary nail, or a combination nail:plate construct. All received structural allografts. Five patients developed nonunion including four subtalar nonunions Preoperative scores on the AOFAS-AHS and MFS were 48.8 ± 14 and 58.3 ± 14. Postoperative scores were 51.2 ± 17 for the AOFAS and 64.5 ± 14 for the MFS. These changes were not statistically significant. However, the difference in nonunions was significant, p < 0.05. CONCLUSION: Failed total ankles can be successfully converted to fusion using structural bone graft and internal fixation. The primary risk appears to be nonunion of the subtalar joint when ankle-hindfoot fusion is required. We believe this risk can be decreased by using a separate approach for preparation of the subtalar joint.

The use of tricortical autograft versus allograft in lateral column lengthening for adult acquired flatfoot deformity: an analysis of union rates and complications.

BACKGROUND: The management of adult acquired flatfoot is an evolving practice with the optimal lateral column lengthening procedure still left to considerable debate. The usual choices include lengthening with the use of autograft or allograft through a calcaneocuboid lengthening arthrodesis or Evans' calcaneal lengthening osteotomy. To our knowledge there is only one other study comparing autograft to allograft in adult lateral column lengthening procedures.(9) The purpose of this study was to evaluate differences with regard to union rates and complications when comparing the use of iliac tricortical autograft versus iliac tricortical allograft supplemented with platelet rich plasma (PRP) in adult acquired flatfoot lateral column lengthening procedures. MATERIALS AND METHODS: The charts and radiographs of 49 patients (51 feet) were evaluated. Twenty total procedures were performed using iliac tricortical autograft and 31 procedures were performed using iliac tricortical allograft with PRP. RESULTS: Successful union was achieved in 14 of 20 (70%) autograft procedures and 29 of 31 (94%) allograft procedures. Thirteen of 20 (65%) of the autograft group and 11 of 31 (35%) of the allograft group had a documented complication other than nonunion. Average length of hospital stay for patients who had procedures using autograft was 3.6 days and those who had allograft was 2.5 days. The average charge for those receiving allograft with PRP, including hospital stay, was roughly $2,500 more than those receiving an autograft procedure. CONCLUSION: Although the numbers were small, we believe that equivalent if not better healing and complication rates are possible with the use of allograft with PRP versus autograft for lateral column lengthening procedures while allowing for similar correction of deformity.

Prospective controlled trial of STAR total ankle replacement versus ankle fusion: initial results.

BACKGROUND: Mobile-bearing ankle replacements have become popular outside of the United States over the past two decades. The goal of the present study was to perform a prospective evaluation of the safety and efficacy of a mobile-bearing prosthesis to treat end stage ankle arthritis. We report the results of three separate cohorts of patients: a group of Scandanavian Total Ankle Replacement (STAR) patients and a control group of ankle fusion patients (the Pivotal Study Groups) and another group of STAR total ankle patients (Continued Access Group) whose surgery was performed following the completion of enrollment in the Pivotal Study. MATERIALS AND METHODS: The Pivotal Study design was a non-inferiority study using ankle fusion as the control. A non-randomized multi-centered design with concurrent fusion controls was used. We report the initial perioperative findings up to 24 months following surgery. For an individual patient to be considered an overall success, all of the following criteria needed to be met: a) a 40-point improvement in total Buechel-Pappas ankle score, b) no device failures, revisions, or removals, c) radiographic success, and d) no major complications. In the Pivotal Study (9/00 to 12/01), 158 ankle replacement and 66 arthrodesis procedures were performed; in the Continued Access Study (4/02 to 10/06), 448 ankle replacements were performed, of which 416 were at minimum 24 months post-surgery at time of the database closure. RESULTS: Major complications and need for secondary surgical intervention were more common in the Pivotal Study arthroplasty group than the Pivotal Study ankle fusion group. In the Continued Access Group, secondary procedures performed on these arthroplasty patients decreased by half when compared with the Pivotal Arthroplasty Group. When the Pivotal Groups were compared, treatment efficacy was higher for the ankle replacement group due to improvement in functional scores. Pain relief was equivalent between fusion and replacement patients. The hypothesis of non-inferiority of ankle replacement was met for overall patient success. CONCLUSION: By 24 months, ankles treated with STAR ankle replacement (in both the Pivotal and Continued Access Groups) had better function and equivalent pain relief as ankles treated with fusion.

Posttraumatic avascular necrosis of the talus.

Avascular necrosis of the talus is one the most challenging problems encountered in posttraumatic reconstruction of the hindfoot. Since the first description of the talus injury in 1608 by Fabricius of Hilden, our knowledge of the talar anatomy, injuries, sequelae, and management has increased significantly. Adequate knowledge of the etiology, the extent of the disease, and the degree of patient symptoms are required to determine optimal treatment.

Simple (unicameral) bone cyst of the calcaneus: a pathologic variant revisited.

A 17-year-old girl was admitted to the hospital for surgery of an enlarging, painful mass of the left calcaneus. Preoperative imaging studies suggested either a simple (unicameral) or aneurysmal bone cyst. Intraoperative biopsy of the lesion revealed a simple bone cyst with extensive cholesterol clefts. Such cysts are not uncommon in the calcaneus. However, the pathology of this case is unusual and often overlooked. The typical presentation, treatment, and pathology of these lesions are reviewed.

The adult clubfoot (congenital pes cavus).

Clubfoot occurs in approximately 1 of every 1000 live births, with multiple theories proposed regarding the cause. The pathologic anatomy of the adult clubfoot consists of four components (cavus, adductus, varus, and equinus) and the specific soft tissue and bony procedures indicated for correction depend completely on the constellation of residual deformity that may exist. If the patient was successfully treated at a younger age and has only limited deformity, all that may be required is symptomatic treatment or bracing. Flexible deformities may be treated with a combination of soft tissue procedures and osteotomies or limited fusions, which will not compromise the essential joints of the ankle, subtalar, and talonavicular joints. More rigid deformities require fusions with their associated functional loss, in an attempt to obtain a plantigrade foot.

Anterior plate supplementation increases ankle arthrodesis construct rigidity.

BACKGROUND: The success of ankle arthrodesis for the treatment of post-traumatic ankle arthritis depends on achieving and maintaining rigid fixation of the prepared tibiotalar interface. The purpose of this study was to examine the biomechanical effect of anterior plate supplementation of a popular three-screw fusion construct. METHODS: Six fresh-frozen cadaver ankles were prepared and instrumented with three partially threaded screws compressing the tibiotalar interface. Testing was done with and without supplementary anterior plate fixation under three different decoupled loading conditions: plantarflexion/dorsiflexion, inversion/eversion, and rotation. Motion at the tibiotalar interface was recorded. RESULTS: Anterior plating increased construct stiffness by a factor of 3.5, 1.9, and 1.4 for the sagittal, coronal, and torsion modes, respectively. Less motion occurred at the tibiotalar interface in all to the three different loading conditions (p = 0.031) with plate supplementation. CONCLUSIONS: Compared to screws alone, anterior plate supplementation increases construct rigidity and decreases micromotion at the ankle fusion interface.

Open fractures of the calcaneus: soft-tissue injury determines outcome.

BACKGROUND: Studies of open calcaneal fractures have been limited and have not analyzed results according to wound location, severity of soft-tissue disruption, fracture type, or treatment method. In this study, results were evaluated on the basis of the hypothesis that early surgical intervention was indicated. METHODS: Between 1989 and 1997, 503 calcaneal fractures were treated at our institution, and forty-three of these fractures, in forty-two patients, were open (8.5%). According to the Gustilo classification there were nine type-I, eight type-II, twelve type-IIIA, and thirteen type-IIIB open fractures as well as one type-IIIC open fracture. All fractures were treated according to the same protocol, consisting of intravenous administration of antibiotics chosen on the basis of the wound type, irrigation and débridement in the operating room, temporary wound coverage, and initial stabilization of the limb. Definitive final fixation was performed after the wound was clean, and soft-tissue swelling was minimal. The final follow-up examinations were performed at a minimum of two years after treatment. Clinical results were graded with use of the AOFAS (American Orthopaedic Foot and Ankle Society) score. RESULTS: An infection developed at the sites of 37% of the forty-three fractures, with osteomyelitis developing at the sites of 19%. Seven of the nine type-I open fractures were treated with open reduction and internal fixation or with primary fusion, with no major complications and a good-to-excellent short-term result. Three of the eight type-II open fractures were complicated by an infection. Three of the twelve type-IIIA open fractures and ten of the thirteen type-IIIB open fractures were complicated by an infection. Six of the infections associated with a type-IIIB open fracture progressed to osteomyelitis, and three of those cases led to an amputation. Overall, thirteen (50%) of the twenty-six type-III open fractures were complicated by an infection, with osteomyelitis occurring in seven (27%). Thirty-three patients with a total of thirty-four open calcaneal fractures were available for follow-up at a minimum of two years, and an average of fifty-five months. The average AOFAS hindfoot score for the twenty-seven patients who had not undergone amputation was 71 points. CONCLUSIONS: Open calcaneal fractures have a high propensity for deep infection despite the use of an aggressive treatment protocol to prevent it. It appears that type-I and type-II open fractures associated with a medial wound can be treated with open reduction and internal fixation. Type-II fractures associated with a wound in another location should be treated with limited or no internal fixation. Type-III open fractures, and especially type-IIIB open fractures, require extensive débridement and prompt soft-tissue coverage as soon as possible. Early internal fixation should be avoided in this subgroup because of the high rates of osteomyelitis and subsequent amputation.