The association of anterior soft tissue depth (ASTD) with wound dehiscence following total ankle arthroplasty

Total ankle arthroplasty (TAA) is a common intervention for the treatment of end-stage ankle arthritis. Unfortunately, use of a longitudinal anterior incision to gain access to the ankle is commonly associated with postoperative wound dehiscence. In this retrospective cohort study the incidence of postoperative anterior wound dehiscence following TAA in 100 consecutive patients was 21 %, and 7 (33.33 %) of the dehiscence cases were serious enough to require additional operative treatment. The anterior soft tissue depth (ASTD) at the level of the tibiotalar joint was measured from the anterior margin of the skin to the anterior margin of the ankle as viewed on the standard lateral radiograph. The overall median ASTD for the entire cohort was 21.79 (range 5.7 to 37.3) mm, whereas that in the non-dehiscence group was 22.06 (5.7, 37.3) mm and that in the dehiscence group was 18.6 (12.78, 35.9) mm, and this difference was statistically significant (p = 0.0240). Receiver operating characteristic (ROC) curve analyses showed that a preoperative ASTD ≤ 16 mm maximized diagnostic sensitivity and specificity and predicted dehiscence.