Satisfactory clinical and radiographic outcomes following revision total hip arthroplasty by direct anterior approach using primary femoral stems at 2-8 years of follow-up.

INTRODUCTION: To report clinical and radiographic outcomes of revision total hip arthroplasty (THA) through the direct anterior approach (DAA) using primary stems.

MATERIALS AND METHODS: The authors assessed a consecutive series of revision THAs operated by DAA using primary (cemented and uncemented) stems between 1/1/2010 and 30/06/2017. The initial cohort comprised 47 patients (50 hips), aged 65 ± 10 years with BMI of 25 ± 4 kg/m2 . Clinical assessment included modified Harris Hip Score (mHHS) and satisfaction with surgery. Radiographic assessment included radiolucent lines > 2 mm, bone remodelling, cortical hypertrophy, pedestal formation, and osteolysis. Linear regression analyses were performed.

RESULTS: Of the 50 hips (47 patients) in the initial cohort, intraoperative complications that did not require re-revision occurred in 5 hips. At a follow-up of > 2 years: 5 hips (10%) were lost to follow-up and 3 hips (6%) required stem re-revision, leaving a final cohort of 42 hips (40 patients). Postoperative complications that did not require re-revision occurred in 4 hips (8%). At 4.3 ± 1.6 years, post-revision mHHS was 89 ± 14 (range 47-100) and 38 patients were satisfied or very satisfied with revision surgery. Bone remodelling was observed in 8 hips (16%), cortical hypertrophy in 6 hips (12%), grade I heterotopic ossification in 7 hips (14%), and grade II in 1 hip (2%). There were no cases of radiolucent lines, pedestal formation, or osteolysis. Regression analyses revealed that post-revision mHHS was not associated with any variable.

CONCLUSIONS: Revision THA performed through the DAA using primary stems grants satisfactory clinical and radiographic outcomes at a minimum follow-up of two years.