Comparison of the outcomes between two 3-component total ankle implants.

BACKGROUND: Total ankle arthroplasty (TAA) with the use of third generation implants has demonstrated favorable clinical results and improved survival. However, few studies have compared the different types of implants. The purpose of this study was to perform a retrospective evaluation of patient outcomes and complications by comparing TAA procedures performed with HINTEGRA versus MOBILITY systems.

METHODS: Fifty-two consecutively enrolled patients (28 men and 24 women; mean age 64.8 years) underwent TAA using HINTEGRA (21 ankles) or MOBILITY (33 ankles) between September 2004 and July 2012. Visual analog scale (VAS) pain scores and the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores were determined at each follow-up visit. The radiographs were reviewed to assess component positioning, radiolucency, heterotopic ossification, and other factors. The mean follow-up period was 28.3 months in the HINTEGRA group and 32.5 months in the MOBILITY group.

RESULTS: VAS decreased from 8.3 to 2.0 for the HINTEGRA group and from 7.9 to 2.7 for the MOBILITY group. The AOFAS score increased from 43.8 to 87.3 for the HINTEGRA group and from 46.6 to 83.7 for the MOBILITY group. Intra- and postoperative malleolar fractures were not noted in the HINTEGRA group, whereas 5 ankles (15.2%) in the MOBILITY group sustained this injury (P = .144). Ankle impingement syndrome was noted in 8 ankles (38.1%) in the HINTEGRA group and 3 (9.1%) in the MOBILITY group (P = .015). However, no significant differences in postoperative osteolysis and neuralgia were noted between the groups.

CONCLUSIONS: Both implants exhibited favorable clinical outcome without significant differences. However, in terms of complications, ankle impingement syndrome was significantly more common in the HINTEGRA group, while intraoperative malleolar fracture was observed only in the MOBILITY group.

LEVEL OF EVIDENCE: Level III, comparative series.