Buechel-Pappas ankle replacement shows good intermediate results at 5 years for OA

Only one patient showed evidence of talar avascular necrosis, but remained asymptomatic at 3 years follow-up.

Performing total ankle replacement for ankle osteoarthritis using the Buechel-Pappas device shows good intermediate results, with 97% of implants surviving at 5 years follow-up, according to a study by British surgeons.

"Our study results demonstrate [that], with careful patient selection, the Buechel-Pappas Uncemented Total Ankle Replacement [Endotech] has good reproducible intermediate term results comparable with other ankle replacements in the literature," the authors wrote.

Gordon A. Higgins, MBChB, MRCS, and colleagues at the Dudley Hospitals Acute Trust reviewed their results implanting the device in 35 ankles of 34 consecutive patients between 1990 and 2005. They published their findings in the Journal of Foot and Ankle Surgery.

The Buechel-Pappas total ankle replacement (TAR) device is a mobile bearing, unconstrained implant with a nitride-coated articulation. It is a non-hydroxyapatite-coated, uncemented implant featuring a porous-coated surface for bone interface, according to the study authors.

In all cases, the surgeon used a standard anterior approach and implanted the tibial prosthesis via a tibial bone window. Postoperatively, patients were placed in a backslab and remained nonweight-bearing for 6 weeks before beginning active physiotherapy.

Patients then progressed to full weight-bearing over the following 6 weeks, according to the study.

All patients underwent TAR for osteoarthritis (OA) at an average age of 69 years, with 70% of cases having post-traumatic OA. Follow-up averaged 5 years.

Preoperatively, the American Orthopaedic Foot and Ankle Society Score averaged 34.6, which significantly improved to 70 at follow-up (P<.001). Also at follow-up, Visual Analog Scale scores for pain averaged 30, function scores averaged 40 and alignment scores averaged 9. Patients had 41° of ankle movement clinically and 44° radiologically, according to the study.

Subjectively, 97% of patients reported being happy with their results, with 66% reporting no pain or only occasional discomfort. In addition, all patients were mobile, with 45% requiring no walking aids, the authors reported.

Radiographs showed no evidence of gross subsidence or lucencies, they noted.

One patient had evidence of talar avascular necrosis, but was asymptomatic at 3-years follow-up. Two patients sustained intraoperative medial malleolar fractures, which the surgeon fixed using threaded cancellous screws. Also, two superficial wound infections occurred, but no patients developed deep infections or nerve injuries, according to the study.

At latest follow-up, only one tibial component had failed and required revision, the authors noted.

For more information:
Ali MS, Higgins GA, Mohamed M. Intermediate results of the Buechel Pappas unconstrained uncemented total ankle replacement for osteoarthritis. J Foot Ankle Surg. 2007;46:16-20.