Defects in the anterior glenoid cause anterior instability of the shoulder joint. According to reports, up to 22% of traumatic anterior dislocations of the shoulder result in some degree of bone loss due to glenoid rim fractures. The failure rate of solely arthroscopic Bankart repair significantly increases for patients with substantial bone defects, ranging from approximately 4% to 67%. In 2007, Yamamoto et al. proposed the concept of "on-track" and "off-track" shoulder joint trajectories as a more geometric approach to studying the engagement of Hill-Sachs and bony defects. It is generally believed that glenoid bone defects exceeding 20% and being "off-track" should be addressed through glenoid bone grafting, utilizing either autologous iliac bone, coracoid transfer (Latarjet surgery), or allograft bone transplantation. Literature research indicates that autologous iliac bone grafting shows superior bone healing and shaping compared to allograft materials, with less bone absorption and higher postoperative shoulder joint stability and functional scores. The position of the iliac bone block plays a crucial role in postoperative functional recovery: a block positioned below the glenoid articular surface may lead to postoperative shoulder joint instability or recurrent dislocation, while a fragment positioned above the glenoid articular surface may result in restricted shoulder joint movement, crepitus, and complications such as osteoarthritis. Relevant studies on the area for harvesting autologous iliac bone, block size, and how to match it with the curvature of the glenoid are still lacking.

To investigate the clinical efficacy of precise iliac bone osteotomy for glenoid bone grafting in the treatment of severe recurrent anterior dislocation of the shoulder joint due to extensive bone defects and assessment of the matching condition between the curvature of the iliac bone graft and glenoid curvature.

The research was conducted retrospectively on patients admitted to the Department of Sports Medicine at Foshan Traditional Chinese Medicine Hospital from December 2020 to June 2022, focusing on recurrent shoulder anterior dislocation cases with severe bone defects. There were 32 cases with complete follow-up data: 30 males and 2 females. Among them, 12 cases involved the left side, while 20 involved the right. The average age was 28.65 years (16 to 41 years old). Preoperatively, dislocation occurrences ranged from 5 to 30 times. Before the surgery, shoulder joint CT measurements were conducted bilaterally to determine the glenoid curvature, defect size, and curvature. Comparisons were made with the normal contralateral glenoid. The defect width ranged from 20.2% to 33.4% (average 26.7%). All cases underwent autologous iliac bone grafting combined with glenoid rim repair surgery. Precise bone harvesting from the iliac crest was performed in an area with a curvature matching the defect in the glenoid, determined by CT measurements of the iliac crest on the same side. Postoperatively, CT measurements were used to assess the matching of the bone block with the glenoid curvature. A follow-up evaluation of shoulder joint function was conducted using the American shoulder and elbow surgeons (ASES), Constant-Murley, and Rowe scores.

All patients underwent postoperative follow-ups, ranging from 12 to 26 months, with an average follow-up of (20.37±6.20). None of the patients experienced postoperative complications such as surgical site infections, recurrent dislocations, iliac bone fracture at the harvesting site, or nerve damage. Immediate postoperative CT measurements revealed consistency between the glenoid curvature and the iliac bone block curvature, with no step formation between the bone block and the glenoid fossa. At one year post-surgery, the bone block completed its shaping, showing osseous healing in all patients during the final follow-up. No subjective instabilities were reported, and the apprehension test results were negative. Regarding shoulder joint function, the average lateral rotation in the preoperative and final follow-up assessments showed no significant difference (60.25±10.57) degrees vs (59.34±7.69) degrees (P>0.05). However, the external rotation at 90° abduction exhibited a statistically significant difference (P<0.05) between preoperative (40.30±14.57) degrees and final follow-up (60.20±16.49) degrees. At the last follow-up, the ASES score improved significantly from (72.43±10.42) to (94.44±5.35) (P<0.05), the Constant-Murley score increased from (80.24±15.40) points to (96.55±2.64) points (P<0.05), and the Rowe score increased from (43.47±8.82) points to (92.45±3.20) points (P<0.05) compared to preoperative values.

Matching the curvature of the iliac crest harvesting site with the glenoid curvature allows for precise iliac bone harvesting. This precision aids in better matching the bone fragment with the glenoid curvature post-shoulder reconstruction, thereby reducing postoperative complications resulting from the bone block being positioned too internally or externally. This approach lowers the risk of iliac bone fractures and contributes to favorable outcomes during the early to mid-term postoperative period.