Activities and participation after primary total hip arthroplasty; posterolateral versus direct anterior approach in 860 patients

BACKGROUND AND PURPOSE: In the past decade, a shift occurred in surgical total hip arthroplasty (THA) approaches to the posterolateral (PLA) and direct anterior approach (DAA). Comparisons of postoperative activities and participation between surgical approaches for THA are sparse. We therefore investigated the association between PLA and DAA for THA regarding the construct “activity and participation” (ICF model) during the first postoperative year. PATIENTS AND METHODS: This was an observational cohort study on osteoarthritis patients scheduled for primary THA in 2 hospitals. Questionnaires to assess the ICF domain “activity and participation” were completed preoperatively, and 3, 6, and 12 months postoperatively (HOOS Activities of daily living (ADL) and Sport and Recreation Function (SR), Hospital for Special Surgery Hip Replacement Expectations Survey, and questions regarding return to work). Each hospital exclusively performed one approach (PLA [Alloclassic-Zweymüller stem] or DAA [Taperloc Complete stem]) for uncemented THA. Hospital was included as instrumental variable, thereby addressing bias by (un)measured confounders. Adjusted mixed-effect models were used, stratified by employment. RESULTS: Total population: 238 PLA (24% employed) and 622 DAA (26% employed) patients. At 12 months, the PLA group had a lower ADL score (–7, 95% CI –12 to –2 points). At 6 months, significantly fewer PLA patients had fulfillment of the expectation sports-performance (OR = 0.3, CI 0.2–0.7]. Other outcomes were comparable. Employed population: At 6 and 12 months, PLA patients scored clinically lower on ADL (respectively –10, CI –19 to 0 and –9, CI –19 to 0 points) and SR (respectively –13, CI –21 to –4 and –9, CI –18 to –1 points). At 6 months, fewer PLA patients fulfilled the expectation joining recreational activities (OR = 0.2, CI 0.1–0.7]. Fulfillment of other expectations was comparable between groups. PLA patients less often returned to work within 3 months (31% vs. 45%), but rates were comparable at 12 months (86% vs. 87%). INTERPRETATION: Overall, functional recovery regarding “activity and participation” was comparable for PLA and DAA. Among employed patients, DAA resulted in better functional recovery and more fulfillment of expectations compared with PLA patients. DAA might also facilitate faster return to work.