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Background Our first-line choice of surgical method for massive shoulder rotator cuff tears not amenable to primary repair is a patching method that uses a graft consisting of a section of the iliotibial band with an attached bone block. The objective of this study was to examine the functional and structural results. Methods The study included 5 patients who were not eligible for primary repair, received iliotibial band autografts with an attached bone block, and could be monitored for 2 years or more. The grafting method involved suturing the ligament part of the graft to the remaining rotator cuff and fixing the bone part to the greater tubercle of the humerus by means of a suture-bridge technique. Clinical evaluation was performed for 24 months postoperatively. Postoperative structural evaluation was performed using computed tomography at 3 to 4 months and magnetic resonance imaging at 6, 12, and 24 months. Results A clear improvement was seen at the final clinical evaluation. Fusion of the bone graft with the greater tubercle of the humerus was confirmed on computed tomography in all patients. No retearing was observed on magnetic resonance imaging at the 24-month point, and the thickness of the ligament part of the graft was maintained. Conclusion The patching method using an iliotibial band with an attached bone block as the graft enabled good reconstruction of the rotator cuff, including the greater tubercle footprint. Moreover, good clinical results were seen at 24 months.

Background Although clinical investigations indicate that the limit of reversibility of rotator cuff muscles fibers type I and II atrophy is grade 2 of fatty degeneration (FD) according to the Goutallier computed tomography classification, little is known about the morphometric verification of these findings. Methods The supraspinatus tendon was detached from the greater tubercle and the infraspinatus and subscapularis in 12 rabbits, and a 12-week observation period followed. This proved to be sufficient for development of grade >2 FD of the supraspinatus tendon. The tendon was then reinserted. The animals were euthanized 24 weeks after tendon reconstruction. The sections of middle part of supraspinatus were stained for adenosine triphosphatase reaction, and morphometric measurements were taken of type I and II muscle fiber diameters. The contralateral shoulders served as controls. Results The macroscopic inspection of the supraspinatus tendons revealed complete healing in all cases. No statistically significant differences were found between controls and operated-on shoulders for type I ( P = .13) and type II ( P = .55) muscle fibers. Conclusions Atrophy of type I and II muscle fibers in rabbit supraspinatus muscle, characterized by grade >2 fatty degeneration according to the Goutallier computed tomography classification, is reversible after 24 weeks from reattachment of its tendon. A requirement for type I and II muscle fibers hypertrophy is a change in the biomechanical and functional conditions of the muscle after its tendon is reconstructed.

Background The objective of this study was to evaluate the topographic relationship between the morphology of the greater tubercle and the insertion of the tendon of the infraspinatus. Materials and methods First, we defined an impression of the greater tubercle, which has not been recognized in classic textbooks, as the "lateral impression" and then measured the dimensions of the "lateral impression" of the greater tubercle in 71 samples of dry bone of humeri. Next, we examined 16 cadaveric humeri with rotator cuff tendons by micro–computed tomography to analyze the positional relationship between the lateral impression and the infraspinatus tendon. Results In all samples of dry bones, the lateral impression could be identified as a triangle shape. The lateral impression was composed of the border with the highest impression (mean, 6.3 mm), the border with the middle impression (mean, 5.0 mm), and the border with the lateral wall of the greater tubercle (mean, 8.5 mm). In all samples of humeri with rotator cuffs, we could confirm the lateral impression, and the border between the highest impression and the lateral impression corresponded to the anterior border of the insertion of the infraspinatus tendon. Conclusion We propose a new anatomic concept of the lateral impression that could enable the precise diagnosis of and facilitate repair techniques for infraspinatus tear, according to specific anatomic characteristics, by applying 3-dimensional computed tomography assessment preoperatively.

Because of the biomechanics of the glenohumeral joint, impairment of rotator cuff function leads to cranial migration of the humeral head, impinging the greater tubercle against the coraco-acromial arch and irritating the subacromial bursa. When bursal irritation has become established, active elevation of the arm against gravity will cause pain within an arc of motion. When a patient with a painful arc is asked to bend forward and let the arm hang, the same arc will become painless. This noninvasive clinical test called the "bow test" is a simple means by which subacromial impingement can be clinically identified as the source of pain in the painful arc of shoulder motion.

Background The attachments of muscles and the position of the humeral head are important for a good functional outcome of shoulder hemiarthroplasties after displaced fractures of the proximal humerus. Deviations in the attachments and changes in their spatial position with respect to the humeral head during surgical reconstruction change the biomechanics and reduce the range of motion of the should joint postoperatively. Methods and Results We used 198 humerus preparations and using 3-dimensional analysis measured the angular relationships between the humeral head axis and medial margin of the greater tuberosity (11.9° ± 9.1°), lateral margin of the lesser tuberosity (48.0° ± 7.8°), and the crest of the greater tuberosity (27.1° ± 9.6°). Conclusion This study provides average values of the positions of the greater and lesser tuberosities with respect to the humeral head axis. We show that the greater and lesser tuberosities are more reliable than the transepicondylar line for reconstruction of humeral head retroversion. Level of Evidence Basic Science.