Objective To investigate the safety and efficacy of a new biodegradable magnesium internal fixation screw for vascularized iliac bone flap grafting in treatment of osteonecrosis of the femoral head (ONFH). Methods Patients with ONFH admitted between July 2020 and February 2021 were selected as the research objects, and 20 patients (20 hips) met the selection criteria and were included in the study. The patients were divided into two groups (n=10) by central random method. The iliac bone flap was fixed with a new biodegradable magnesium internal fixation screw in the trial group, and the iliac bone flap was wedged directly in the control group. There was no significant difference (P>0.05) in gender, age, and side, type, Association Research Circulation Osseous (ARCO) stage, and disease duration of ONFH between the two groups. The operation time and intraoperative blood loss of the two groups were recorded. Laboratory tests were performed at each time point before and after operation, including white blood cell (WBC), electrolytes (K, Ca, P, Mg), blood urea nitrogen (BUN), serum creatinine (Scr), glomerular filtration rate (eGFR), lymphocyte ratio (CD4/CD8), immunoglobulin G (IgG), IgM, alanine transaminase (ALT), aspartate aminotransferase (AST). After operation, Harris score was used to evaluate the hip joint function. CT of the hip joint and X-ray films in anteroposterior and frog positions of the pelvis were used to review the iliac bone flap position, fusion, and screw biodegradation in the trial group. Results The vital signs of the two groups were stable, the incisions healed by first intention, and no adverse events occurred after operation. One patient in the control group refused to return to the hospital for follow-up at 3 months after operation, and 1 patient in the trial group refused to return to the hospital for follow-up at 1 year after operation. The rest of the patients completed the follow-up at 2 weeks, 3 months, 6 months, and 1 year after operation. Laboratory tests showed that there was no significant difference in WBC, electrolytes (K, Ca, P, Mg), BUN, Scr, eGFR, CD4/CD8, IgG, IgM, ALT, and AST between the two groups at each time point before and after operation (P>0.05). The operation time and intraoperative blood loss of the trial group were significantly less than those of the control group (P<0.05). The Harris scores of the two groups at 1 year significantly increased when compared with the values before operation and at 6 months after operation (P<0.05). There was no significant difference in Harris score between the two groups at each time point (P>0.05). Postoperative CT of hip joint and X-ray films of pelvis showed that the iliac bone flap reached osseous fusion with the fenestration of the head and neck junction of femoral head in the two groups at 1 year after operation, and no loosening or shedding of iliac bone flap was observed during follow-up. In the trial group, there were signs of dissolution and absorption of the new biodegradable magnesium internal fixation screws after operation, and the diameter of the screws gradually decreased (P<0.05); no screw breakage or detachment occurred during follow-up. Conclusion In the treatment of ONFH with vascularized iliac bone flap grafting, the new biodegradable magnesium internal fixation screws can fix the iliac bone flap firmly. Compared with the traditional iliac bone flap wedging directly, it has a shorter operation time, less intraoperative blood loss, and can obtain similar joint function.
ObjectiveTo observe the effectiveness of digital subtraction angiography (DSA) assisted musculoskeletal flap transplantation in the treatment of osteonecrosis of the femoral head (ONFH).MethodsThe clinical data of 15 patients with 15 hips of ONFH admitted between January 2016 and December 2019 were retrospectively analyzed. All patients were male, aged 20-45 years, with an average age of 31.6 years. There were hormone type in 9 cases and alcohol type in 6 cases. The disease duration ranged from 15 days to 3 years, with an average of 8 months. The Association Research Circulation Osseous (ARCO) staging: 4 hips in stage Ⅱ, 11 hips in stage Ⅲ. The preoperative visual analogue scale (VAS) score was 6.2±0.2, and the Harris score of the hip joint was 57.3±1.3. Preoperative DSA examination of the femoral head was performed to determine the location of vascular lesions of the femoral head. According to the results of the angiography, the surgical selection of the musculoskeletal flap was guided. For the patients with both superior and inferior retinaculum vessels developed, simple core decompression was performed. For the patients with superior retinaculum vessels developed but inferior retinaculum vessels not developed, anterolateral tensor fasciae flap was used. For the patients whose superior retinaculum did not develop and the inferior retinaculum developed, posterolateral quadratus femoris flap was used. The fibular flap with anastomotic vessels was used in the patients whose superior and inferior retinaculum vessels were not developed.ResultsAll 15 cases of 15 hips were followed up 6-24 months, with an average of 14 months. During the follow-up, the patient’s ONFH did not worsen, the femoral head did not collapse, the joint space was normal, and the hip joint fextion and extension function was acceptable. At last follow-up, the VAS score was 1.9±0.2, and the hip Harris score was 92.1±0.8, both of which were significantly improved when compared with preoperative ones (t=14.85, P=0.00; t=23.22, P=0.00).ConclusionFor patients with ONFH who need musculoskeletal flap transplantation, preoperative DSA of femoral head can determine the location of vascular lesions of femoral head, so as to guide the selection of musculoskeletal flap transplantation, which is of great significance for hip-conserving surgery.