Pain and function following total hip arthroplasty. A 2-year comparison between the direct anterior and the anterolateral approach

Background: Defining the most effective surgical approach for total hip arthroplasty (THA) is still a controversial issue. The purpose of the current study was to compare the short-term post-operative pain and function between patients who underwent THA through an anterolateral (AL) approach to those who underwent the surgery through a direct anterior (DA) approach.

Methods: 80 patients underwent elective THA and met the inclusion criteria. 40 patients were operated through an AL approach and 40 patients were operated through a DA approach. Patients` characteristics were collected from the medical records. The Oxford Hip Score (OHS) was used to assess pain and function. Univariate comparisons were done to examine differences between groups. Spearman correlation was used to examine the relationship between patients` characteristics and OHS.

Results: There were no significant differences between groups in age, BMI and time elapsed since surgery to questionnaire completion. A significant difference was found between groups in OHS (p<0.001). Patients in the AL approach group reported a mean (SD) OHS of 38.3 (9.4), while patients in the DA group reported a mean (SD) OHS of 44.4 (6.0). Sub-analysis of the OHS items revealed significant differences in some pain and function items, mainly in locomotion aspects including limping when walking, stand up from a chair, pain interfered with work, walking tolerance, climb a flight of stairs, car/transportation, and shopping, while others did not differ. There were no significant correlations between patients` characteristics and OHS.

Conclusion: Patients who underwent THA through a DA approach reported significantly better OHS score compared to patients who underwent THA through an AL approach when assessed at a short-term follow-up period. The source of differences was mainly in aspects of locomotion.