This study is a prospective randomized controlled case study and used blind methods. The evaluator is trained and does not know the specific test plan. This study involved human participants and all procedures performed in the study were in accordance with the Medical Institution Administration Regulation, conformity with the ethical standards of the National Research Council and Helsinki Declaration. This study was approved by the Ethics Committee of Affiliated Hospital of Xuzhou Medical University, registration number (XYEY2014-xjs010-02).
All patients undergoing primary THA at our hospital from January 2015 to April 2017. All patients received the same THA care, pain management, and rehabilitation program before and after surgery. Gait analysis was performed at the gait analysis laboratory of Xuzhou Medical University.
Inclusion criteria:(1)Primary bilateral simultaneous THA;(2) Implanted with the same design and type of uncemented prosthesis on both sides;(3) Hip osteoarthritis;(4) Avascular necrosis of femoral head;(5) DDH (Crowe Type 1 or2);(6) Informed consent, signed informed consent, and agreement to participate in clinical research;(7) Same surgeon.
Exclusion criteria;(1) Severe internal medical disease comorbidities;(2) Severe hip anatomic deformity;(3) History of hip infection;(4) Ipsilateral lower extremity deformity;(5) Diseases in other ipsilateral joints;(6) Neurological or musculoskeletal diseases affecting gait;(7) Reluctant to join this clinical research.
After the evaluation, 37 patients were eligible for this study, 15 patients refused to join the study, and 2 patients were lost for follow-up. A total of 20 patients were included in the study, 9 males and 11 females with an average age of 63.0 years old (range 51-73). Patients were randomly assigned before surgery and sealed opaque envelopes were created using computer generated random lists. (Fig1)
All patients underwent general anesthesia. All operations were performed by the same surgeon in the same hospital, and the surgeon was specially trained and experienced in both approaches. And before the study, the doctor went far beyond the learning curve and completed hundreds of DAA and PLA total hip arthroplasty independently.
DAATHAs take the lateral decubitus position, starting from 2 cm below and outside of the anterior superior iliac spine, and making a surgical incision about 10 cm long to the distal end. The fascia of the skin, subcutaneous, and fascia lata is cut open layer by layer. The outer cutaneous nerve is protected and the lateral branch of the circumflex femoral artery is ligated. The fat pad above the joint capsule was removed, the joint capsule was fully exposed, the front hip joint capsule was removed, and the femoral neck was revealed. The femoral neck was amputated and the femoral head was removed. Excision of the acetabular peripheral hyperplasia and foreign body, and then gradually increase the diameter of the acetabulum to polish the acetabulum, control the proper anteversion and inclination angle, and increase the diameter of the acetabulum to the appropriate size., install the cup, put the acetabular lining. The hip joint is externally rotated and extended, and the proximal end of the femur is raised to expand the medullary cavity. The femoral stem prosthesis is inserted into the medullary cavity and pressed tightly, and then the femoral head is mounted. Reset the hip joint, check hip stability, and compare the length of both lower limbs. Place a drainage and suture the wound.
PLATHAs take the lateral decubitus position. Taking the apex of the great trochanter as the center point, making an arc incision about 13 cm in length. The skin, subcutaneous tissue, and fascia lata were cut layer by layer, and the external rotation muscle group was exposed and separated. The posterior joint capsule was exposed and cut, the femoral neck was exposed, the femoral neck was cut, and the femoral head was taken out. Excision of the acetabular peripheral hyperplasia and foreign body, and then gradually increase the diameter of the acetabulum to polish the acetabulum, control the proper anteversion and inclination angle, and increase the diameter of the acetabulum to the appropriate size., install the cup, put the acetabular lining. Exposing the proximal femur and expanding the medullary cavity. The femoral stem prosthesis is inserted into the medullary cavity and pressed tightly, and then the femoral head is mounted. Reset the hip joint, check hip stability, and compare the length of both lower limbs. Place a drainage and suture the wound.
All patients were treated with the same nutritional intervention, antibiotics, thrombosis prevention, perioperative pain management, and the same nursing and rehabilitation exercise program. One hour before the operation, all patients received cefazolin according to body weight. Postoperative analgesia was administered with 200mg celecoxib orally. Drainage tubes were not attached in incision. The wound dressing change was carried out by the same doctor, and the patients were guided to walk with the walker after the operation, and informed of the relevant precautions and the standard preventive measures to prevent dislocation. Blood transfusion was determined according to the clinical manifestation and blood routine test results, such as patients with obvious anemia symptoms or hemoglobin below 70g / L will be given blood transfusion. All patients started subcutaneous injection of low molecular weight heparin 12 hours after surgery (4100IU, qd, Clexane, Sanofi-Aventis, France). Continued oral rivaroxaban after discharge (5mg, qd, Xarelto, Bayer, Cologne, Germany). To prevent deep venous thrombosis of lower limbs, the minimum time of anticoagulation is 5 weeks. Standard rehabilitation programs, including weight-bearing and assisted walking, were implemented the next day after surgery. Hip flexion reaches 100° flexion and 40° abduction and can walk independently and safely, the patients can leave the hospital.
The preoperative and postoperative data of the patients were collected by the graduate students, and the intraoperative data were collected according to the surgical records. Hip joint X-ray for imaging evaluation (including position and stability of prosthesis) and the patients were reviewed in the outpatient according to the routine THA review program (first review is in the sixth week and every three months thereafter). D’Aubigne - Postel score for hip function assessment. VAS score for pain assessment.
At the same time, all patients were asked to answer the same questions, these questions were not included in the D’Aubigne - Postel score. Ask the patient which side is better and why (provide explanation if possible)? If they have to undergo total hip arthroplasty, which method they would recommend.
Gait analysis was performed before and 3 and 6 months after surgery. All gait analyses were performed by the same professional two technicians, who did not participate in patient care and were unaware of the clinical information of all patients. According to gait analysis protocol，a total of 29 markers are attached to the bilateral lower extremity bony markers( including anterior superior iliac spine, posterior superior iliac spine, sacral, thigh, knee, tibia, heel, ankle, toe )[13, 14].
Statistical data were processed using SPSS 23.0 statistical software and a threshold of significance of p <0.05. Results were reported as mean ± SD(`X±S). Demographic and clinical data were compared between the DAA and PLA groups using Pearson’s chi-squared test. Inter-group differences were assessed for significance using independent t tests after confirming that the data followed a normal distribution.