To compare the effectiveness of total ankle replacement (TAR) using modified anterolateral and anterolateral approaches in the treatment of elderly ankle osteoarthritis (OA).

The medical records of 87 elderly patients with ankle joint OA who were diagnosed and treated in the hospital from August 2019 to December 2023 were retrospectively collected, among which 83 cases received complete follow-up. There were 46 males and 37 females with an average age of (66.55±2.76) years. According to the different approaches of TAR surgery, the medical records of 41 patients who received anterior lateral approach TAR treatment were assigned to Group A, while the medical records of the remaining 42 patients who received modified anterior lateral ankle approach TAR treatment were assigned to Group B. Perioperative indicators, ankle joint function, ankle joint range of motion, and postoperative complications were ompared between two groups.

83 elderly patients with ankle osteoarthritis were fully followed up, with a follow-up rate of 95.40% and a follow-up time of 6-14 months, with an average of (10±2) months. The follow-up period for Group A was 6-13 months, with an average of (9±2) months. The follow-up period for Group B was 7-14 months, with an average of (10±2) months. The first postoperative time for getting out of bed in Group B (7.32±1.84) weeks was shorter than that in Group A [(8.42±2.24) weeks, t=2.447, P=0.017]. The initial weight-bearing walking time of Group B (14.11±1.97) weeks was shorter than that of Group A [(15.73±2.78) weeks, t=3.069, P=0.003]. After 6 months of surgery, the American Association of Foot and Ankle Surgeons (AOFAS) scores (51.35±4.21), 63.21±3.52, and 72.11±2.64) in Group B were higher than those in Group A [48.53±3.46, 60.42±3.61, and 69.45±2.56, P<0.001]. After 6 months of surgery, the range of motion of the dorsiflexion, plantar flexion, eversion, and varus joints in Group B [(31.55±3.85) °, (36.63±5.21) °, (24.64±3.71) °, (25.58±4.75) °] was higher than that in Group A [(28.63±4.64) °, (33.53±5.31) °, (21.31±3.64) °, (22.46±3.53) °], t=3.123, t=2.685, t=3.390, P=0.003, P=0.009, P<0.001, P=0.001]. The incidence of postoperative complications in Group B (9.52%) was not statistically significant compared to Group A (7.32%) (P=1.000).

Compared to the anterior lateral approach, the modified anterior lateral ankle joint approach for TAR treatment can shorten the postoperative time for getting out of bed and weight-bearing activities in elderly patients with ankle osteoarthritis, which is more conducive to improving postoperative ankle joint function and range of motion, and does not increase the incidence of complications.