[Short-term efficacy of endoscope assisted arthroplasty for total hip replacement via a minimum invasive direct anterior approach].

Objective: To present the surgical technique of endoscope assisted arthroplasty for total hip replacement via minimum invasive direct anterior approach and analyze its early clinical outcome. Methods: From November 2019 to May 2020, endoscopic total hip arthroplasty via direct anterior approach was performed on 30 patients (32 hips), including 12 males (13 hips) and 18 females (19hips), in the Department of Orthopedics of Fujian Provincial Hospital. The average age of patients was (63±14) years (ranged 32-87 years). The average body mass index (BMI) of the patients was (26.9±4.5) kg/m2. There were 12 cases whose BMI was higher than 28.0 kg/m2 and the maximum BMI was 35.2 kg/m2. The surgery was performed on supine position using a 5-6 cm proximal transverse incision and a distal selective percutaneous puncture incision to perform the acetabulum preparation and the prosthesis implantation with the novel designed split tool under the monitoring of endoscope; the lift-top tractor system was used to raise the femur in the transverse incision for femoral side preparation and prosthesis implantation. Relevant data such as the perioperative status, operation time, postoperative pain score assessed with visual analogue score (VAS), prosthesis position, joint function, lateral femoral cutaneous nerve function and patient satisfaction were recorded to analyze the short-term efficacy. Results: The average length of incision of the 30 cases(32 hips)was (5.9±0.4) cm. All patients in this study had I/A wound healing with no perioperative complications such as infection, poor wound healing and fractures of the proximal femur. The average operation time was (65±14) min, and the average amount of blood loss was (136±56) ml. The average acetabular abduction angle and acetabular antegrade inclinations was 41.4°±3.6° and 16.0°±5.3°, respectively. The resting-state VAS of pain at 6 h and 24 h after operation were all ≤2, and there was no significant difference between the VAS scores after exercise and the VAS scores at the resting state (both P>0.05). There was no statistically significant difference between the VAS scores at the same state at different times (both>0.05). The weight-bearing exercise was applied in all patients within 12 h after surgery. The length of postoperative hospital stays varied from 1 to 3 days((2.0±0.9) days). At the 6th-month follow-up, the Harris score of the hip was 94.7±3.0, which significantly improved when compared with that before the operation (35.5±8.1)(P<0.01). No sensory abnormalities were observed. The satisfaction score of the patients was 9.3±0.5 (full score set to 10). Conclusions: The efficacy and safety of the endoscope assisted total hip arthroplasty for total hip replacement is acceptable. This procedure can help to reduce the compression of the muscles by the retractor in the conventional operation. It can be applied to obese and muscular patients.