Lateral versus direct anterior approach in total hip arthroplasty: evaluation of short- and medium-term clinical outcomes with the Forgotten Joint Score-12

BACKGROUND: This study aims to compare the short-term and mid-term outcomes of two surgical approaches for total hip arthroplasty (THA) in terms of pain and scores obtained at the Forgotten Joint Score (FJS), at the modified Harris Hip Score (mHHS), and at the Numeric Rating Scale (NRS) questionnaires. Two groups of patients were examined: one of them underwent THA via a direct anterior approach (DAA), while the other via a direct lateral approach (transgluteal approach according to Bauer).METHODS: In this prospective study, 130 patients undergoing THA were enrolled. Each patient received the mHHS, FJS, and NRS questionnaires at 3 months, 6 months, 1 year, and 2 years post-surgery. Statistical analysis was conducted applying the ANOVA method, and a Sidak test was performed to compare the resulting means of the two groups.RESULTS: A statistically significant difference was observed between the two patient groups (P<0.0001) at the FJS, mHHS, and NRS questionnaires within the first 6 months post-surgery, favoring the DAA approach. At 12 months post-surgery, a smaller difference was observed between the two groups, with a lesser level of significance (FJS, NRS P<0.05, while NRS P<0.001). At 2-year follow-up, there was no difference between the two surgical approaches. The analysis of results collected 3 and 6 months post-surgery reveals a considerable difference between the two surgical approaches in terms of pain and prosthesis perception (FJS), demonstrating the significant impact of the chosen surgical approach. Future studies, eventually based on surveys at 3-, 5- and 10-years post-surgery may confirm or refuse the hypothesis that the long-term results of the direct lateral approach are comparable to those of the direct anterior approach.CONCLUSIONS: THA performed through a direct anterior approach provides better short- and medium-term results. Patients experience less pain, they forget about the implant sooner and they go back more easily to their normal daily-life activities, as shown by the results at both the mHHS and the FJS.