Fusion Sign of Tendon-to-Bone Healing on X-Ray after Rotator Cuff Repair

Purpose: In clinical practice, increased radiolucency at the insertion site of a repaired tendon on the humerus on postoperative radiographs of patients following rotator cuff repair is often observed. Separately, magnetic resonance imaging (MRI) revealed tendon-to-bone healing in conjunction with this finding. Thus, we suspected that such radiographic changes are associated with tendon-to-bone healing, a phenomenon we labeled as the “fusion sign.” This study sought to investigate the diagnosis rate of the fusion sign in relation to tendon-to-bone healing after rotator cuff repair. Methods: Patients who underwent open rotator cuff repair (ORCR) or arthroscopic rotator cuff repair (ARCR) at two centers from 2010 to 2018 and who underwent MRI more than 6 months postoperatively were included in this study. The presence of radiolucency of the humeral footprint on a radiograph (the fusion sign) was investigated and checked for the concurrent presence of tendon-to-bone healing on MRI. Results: In total, 187 shoulders after ARCR and 55 shoulders after ORCR were included in this study. Among these, SH repair was performed in 202 shoulders and suture-bridging repair was performed in 40 shoulders. The fusion sign was positive in 67.8% of cases and negative in 32.3%. The positive predictive value (PPV) of the total population was 0.963 and did not differ according to the suture method used, reported as 0.964 in ARCR, 0.962 in ORCR, 0.966 in the surface-holding technique, and 0.938 in the suture-bridging technique. The intraobserver reliability was ĸ = 0.4478 (p < 0.001). The interobserver reliability for all observers was ĸ = 0.408 (p < 0.001). Conclusion: Postoperatively, the presence of the fusion sign at the footprint of the humerus strongly suggests that tendon-to-bone healing has occurred.

Rotator Cuff Reconstruction and Humeral Head Replacement Using Smaller Humeral Prostheses in Cuff Tear Arthropathy Patients under 70 Years of Age

Background: Most reverse shoulder arthroplasty (RSA) studies have shown good improvement in arm elevation without improvements in external rotation (ER). In addition, high rates of complications after long-term RSA have been reported, suggesting that RSA should be limited to elderly patients, especially those who are older than 70 years old. Since 2001, we have developed a strategy of rotator cuff reconstruction with muscle transfer and humeral head replacement (HHR), using smaller humeral prostheses, in cuff tear arthropathy patients. The aim of the present study was to investigate the clinical outcome of our strategy in patients under 70 years of age who had irreparable rotator cuff tears and osteoarthritis. Materials and Methods: A total of 25 shoulders of 25 patients under 70 years of age (males, 15;females, 10) with irreparable cuff tears were treated with HHR and cuff reconstruction. The average age at the time of surgery was 64.3 years (range, 55 - 69) and the average follow-up period was 38.7 months (range, 24 - 72). The cuff defect was repaired using a partial subscapularis transfer in 14 shoulders;nine shoulders required a latissimus dorsi transfer, one required a pectoralis major transfer, and one required both a latissimus dorsi and a pectoralis major transfer. Clinical outcomes were assessed with the range of motion (ROM), UCLA score, Japanese Orthopaedic Association (JOA) score and postsurgical complications. Results: Shoulder pain was diminished in all patients after surgery. The preoperative UCLA and JOA scores were 13.1 and 47.0 respectively, improving to 28.6 and 81.5 respectively after surgery. Active forward flexion has improved from an average of 89.0° to 138.8°, and the ER improved from an average of 16.2° to 33.2°. No complications occurred after surgery. Conclusion: Anatomical reconstruction using smaller head humeral prostheses yielded favorable results and less complication, compared with RSA. Considering another advantage of ability to retain glenoid bone stock, the current procedure can be a useful option for irreparable rotator cuff tears with OA in patients under 70 years old.