Predictive factors for forgotten joints after direct anterior approach total hip arthroplasty

BACKGROUND: Research indicates that the Direct Anterior Approach (DAA) for Total Hip Replacement (THA) may achieve a higher degree of joint oblivion compared to other approaches. However, the factors predicting postoperative joint awareness following DAA-THA remain unclear. METHODS: In this retrospective research, 165 patients with hip osteoarthritis who underwent DAA-THA at our hospital between 2020 and 2022 were selected, with a minimum postoperative follow-up of 2 years. Patients were categorized into the Forgotten Joint Group and Non-Forget Joint Group based on their response to the Patients' Joint Perception (PJP) anchor question. Univariate and multivariate logistic regression analyses were performed using preoperative and intraoperative factors as potential predictors. Postoperative patient-reported outcome measures (PROMs) were excluded from the final multivariate model to avoid circularity. RESULTS: A total of 165 patients were included in the data analysis. The Forgotten Joint Group comprised 29 patients, and the Non-Forgotten Joint Group 136 patients. Preoperative radiographic severity(Kellgren-Lawrence grade), bone mass, and change in femoral offset (ΔFO) showed significant difference (P < 0.001).No significant differences were observed in gender, age, surgical side, BMI, albumin, smoking, drink, ASA grade, or VAS score (P > 0.05). According to the multivariate logistic regression model, preoperative radiographic severity was associated with "Forgotten Joint" [OR = 1.720 (95% CI:1.110-2.696), p = 0.002], Osteoporosis was associated with a lower likelihood of "Forgotten Joint" [OR = 0.205 (95% CI: 0.075-0.523), p = 0.001] and ΔFO was positively associated with "Forgotten Joint" within a certain range [OR = 1.520 (95% CI: 1.225-1.891), p = 0.001]. CONCLUSION: This study indicates that poorer preoperative radiographic scores were associated with lower joint awareness, whereas osteoporosis was associated with higher joint awareness. Furthermore, a greater femoral offset reconstruction within the normal range was associated with achieving a forgotten joint.