Muscular strength and function after total hip arthroplasty performed with three different surgical approaches: one

Surgical approach influences short-term muscular strength, and leg-strength asymmetry has been demonstrated after total hip arthroplasty (THA). We evaluated muscular strength, physical function and patient-reported outcome measures (PROMs) up to 12？months postoperatively, in patients operated on using 3 different surgical approaches. 60 patients scheduled for primary THA were allocated to the direct lateral (DLA), posterior (PA) or anterior (AA) approach. The following parameters were evaluated: leg press and abduction strength, pain, 6-minute walking test, Harris Hip Score and Hip disability and Osteoarthritis Outcome Score - Physical Function Shortform (HOOS-PS). Abduction strength in the DLA group was significantly more reduced than the PA and AA groups 12？months postoperatively (p < 0.001). A significant interleg difference in abduction (p < 0.01) and leg press (p < 0.03) persisted in all groups up to 6？months, and up to 12？months in the DLA (p < 0.05). In the AA group, interleg difference in leg press was present up to 12？months (p = 0.01). Pain scores were higher in the DLA than the AA group at 6？months (p = 0.01). Patients in the PA group had better HOOS-PS score than those in the DLA group 3？months postoperatively (p = 0.02). No intergroup differences in pain or PROMs were found 12？months postoperatively. Patients operated via the DLA had reduced muscular strength, HOOS-PS scores and higher pain scores than those who underwent PA and AA type surgery. The non-operated leg was significantly stronger than the operated leg in all groups 6？months postoperatively and this persisted up to 12？months postoperatively for the DLA and AA groups. Clinical Trial Protocol number: ClinicalTrials.gov (NCT01506024)