Background. Humeral retroversion is variable among individuals, and there are several measurement methods. This study was conducted to compare the concordance and reliability between the standard method and 5 other measurement methods on Twodimensional (2D) computed tomography (CT) scans. Methods. CT scans from 21 patients who underwent shoulder arthroplasty (19 women and 2 men; mean age, 70.1 years [range, 42 to 81 years]) were analyzed. The elbow transepicondylar axis was used as a distal reference. Proximal reference points included the central humeral head axis (standard method), the axis of the humeral center to 9 mm posterior to the posterior margin of the bicipital groove (method 1), the central axis of the bicipital groove –30° (method 2), the base axis of the triangular shaped metaphysis +2.5° (method 3), the distal humeral head central axis +2.4° (method 4), and contralateral humeral head retroversion (method 5). Measurements were conducted independently by two orthopedic surgeons. Results. The mean humeral retroversion was 31.42° ± 12.10° using the standard method, and 29.70° ± 11.66° (method 1), 30.64°± 11.24° (method 2), 30.41° ± 11.17° (method 3), 32.14° ± 11.70° (method 4), and 34.15° ± 11.47° (method 5) for the other methods. Interobserver reliability and intraobserver reliability exceeded 0.75 for all methods. On the test to evaluate the equality of the standard method to the other methods, the intraclass correlation coefficients (ICCs) of method 2 and method 4 were different from the ICC of the standard method in surgeon A (p < 0.05), and the ICCs of method 2 and method 3 were different form the ICC of the standard method in surgeon B (p < 0.05). Conclusions. Humeral version measurement using the posterior margin of the bicipital groove (method 1) would be most concordant with the standard method even though all 5 methods showed excellent agreements

Purpose. The presence of a Hill-Sachs lesion is a major contributor to failure of surgical intervention following anterior shoulder dislocation. The relationship between lesion size, measured on pre-operative MRI, and risk of recurrent instability after surgery has not previously been defined. Hypothesis: We hypothesized that the size of Hill-Sachs lesions on pre-op MRI would be greater among patients who failed soft tissue stabilization when compared to patients who did not fail. We also hypothesized that the existence of a glenoid lesion would lead to failure with smaller Hill-Sachs lesions. Method. Nested case-control analysis of 114 patients was performed to evaluate incidence of failure after soft tissue stabilization. Successful follow-up of at least 24 months was made with 91 patients (80%). Patients with recurrent instability after surgery were compared to randomly selected age and sex matched controls in a 1:1 ratio. Pre-operative sagittal and axial MRI series were analyzed for presence of Hill-Sachs lesions, and maximum edge-to-edge length and depth as well as location of the lesion related to the bicipital groove (axial) and humeral shaft (sagittal) were measured. Results. Of 91 patients included in analysis, 77 (84.6%) had identifiable Hill-Sachs lesions. 32 patients (35.2%) suffered from failure of soft tissue stabilization (redislocation 22.0%; subjective instability 13.2%). Ten of these patients (11.0%) underwent further surgery. When comparing the age and sex matched failure and control groups, statistically significant differences in unadjusted data were found for axial edge-to-edge length (p = 0.01), axial depth (p = 0.01), and sagittal edge-to-edge length (p = 0.04), with larger sized lesions found in the failure group (Figure 1). Differences trended towards significant for sagittal depth and angle from the bicipital groove. Conclusion. In this retrospective case-control study, humeral head defect size was positively correlated with recurrent instability after soft-tissue stabilization. Larger Hill-Sachs lesions, as measured on pre-op MRI, were found in patients who failure surgical intervention when compared to patients who did not fail. These data and future studies may help determine pre-operative clinical guidelines for the treatment of anterior shoulder dislocation

Revision of the humeral component in shoulder arthroplasty is frequently necessary during revision surgery. Newer devices have been developed that allow for easy extraction or conversion at the time of revision preserving bone stock and simplifying the procedure. However, early generation anatomic and reverse humeral stems were frequently cemented into place. Monoblock or fixed collar stems make accessing the canal from above challenging. The cortex of the Humerus is far thinner than the femur and stress shielding has commonly led to osteopenia. Many stem designs have fins that project into the tuberosities putting them at risk for fracture on extraction. Extraction starts with an extended deltopectoral incision from the clavicle to the deltoid insertion. The proximal humerus needs to be freed from adhesions of the deltoid and conjoined tendon. The deltopectoral interval is fully developed. Complete subscapularis and anterior capsular release to the level of the latissimus tendon permits full exposure of the humeral head. After head removal the stem can be assessed for loosening and signs of periprosthetic joint infection. The proximal bone around the fin of the implant should be removed from the canal. If possible, the manufacturer's extractor should be utilised. If not, then a blunt impactor can be placed from below against the collar of the stem to assist in extraction. With luck the stem can be extracted from the cement mantle. If there is no concern for infection, the cement-in-cement technique can be used for revision. Otherwise, attempts should be made to extract all the cement and cement restrictor, if present. The small cement removal tools from the hip set can be used and specialised shoulder tools are available. An ultrasound cement removal device can be very helpful. The surgeon must be particularly careful to avoid perforation of the humeral cortex. This is especially important when near the radial nerve as injury can occur. When a well-fixed stem is encountered, an osteotomy of the proximal humerus is necessary. The surgeon can utilise a linear cut with an oscillating saw along the bicipital groove for the length of the implant. An osteotome is used to crack the cement mantle allowing stem extraction. Alternatively, a window can be created to offer additional access to the cement mantle. In the event the surgeon has required an osteotomy or window, cerclage wires, cables or suture will be needed and when the bone is potentially compromised, allograft bone graft struts (tibial shaft) are used for additional support. Care is needed when passing cerclage wires to avoid injury to the radial nerve which is adjacent to the deltoid insertion. If infection is suspected or confirmed an ALBC spacer is placed. When single stage revision is planned both cemented and uncemented stem options are available. Cement placed around the humeral stem has been suggested to decrease infection incidence. Revision of cemented humeral stems is a continued challenge in revision shoulder surgery. Newer systems and reverse total shoulder options have improved the surgeon's ability to achieve good outcomes when revising prior shoulder arthroplasty

Purpose:. The objective of this study was to determine the tensile strength of the different components of the rotator cuff tendons and their relationship to rotator cuff tears. Method:. The tests were done on a newly designed and built test-bench that performed the tests at a consistent rupture speed. The tests were done on four fresh frozen cadaver shoulders. The capsular and tendinous layers of the rotator cuff were divided leaving them only attached on the humeral side. Separate tensile tests were done on these tendons, after they were divided into 10 mm wide strips before testing. The tendon thickness was also measured. Results:. The maximum force tolerated by these tendons is comparable. The elongation however is not the same; the tendinous part of the tendon elongated more. The strength of the “rotatorhood” was then determined. This is a thin layer of tendon extending beyond the greater tuberosity, connecting the supra-spinatus to the sub-scapularis via the bicipital groove. The 10 mm of the “rotator hood” ruptured at an average force of 70 Newtons. Conclusion:. 1. The two layers of the rotator cuff contribute equally to the cuff's strength. 2. The difference in elongation of the tendinous and capsular layers makes the capsular layer more vulnerable to elongation stress. 3. The “rotatorhood” is a strong important structure with a mechanically advantageous insertion

Background:. Massive rotator cuff tear can cause functional disability due to instability and degenerative changes of the shoulder joint. In patients with massive irreparable rotator cuff tear, tendon transfer is often used as the salvage procedure. Latissimus dorsi and pectoris major transfer are technically demanding procedures and may incur complications. The biceps tendon transfer may provide a biologically superior tissue patch that improves the biomechanics of the shoulder joint in patients with irreparable rotator cuff tear. This study evaluated the functional outcomes of biceps tendon transfer for irreparable rotator cuff tear in 6 patients with two years and longer follow-up. Methods:. Between September 2006 and October 2011, 50 patients with 50 shoulders underwent surgical repair for MRI confirmed rotator cuff tear. Among them, six patients with massive irreparable rotator cuff tear were identified intraoperatively, and underwent proximal biceps tendon transfer to reconstruct the rotator cuff tear. The biceps tendon was tenodesed at the bicipital groove, and the proximal intra-articular portion of the biceps tendon was transected. The biceps graft was fanned out and the distal end fixed to the cancellous trough around the greater tuberosity with suture anchor. The anterior edge was sutured to the subscapularis and the posterior edge to the infraspinatus tendon or supraspinatus if present. Postoperative managements included sling protection and avoidance of strenuous exercises for 6 weeks, and then progressive rehabilitation until recovery. Results:. The evaluation parameters included VAS pain score, UCLA score, Constant score and AHES score, and X-rays of the shoulder. At follow-up of 25.3 ± 25.0 (range 22 to 63) months, the mean VAS pain score decreased from 9.3 ± 0.8 preoperatively to 1.7 ± 1.4 postoperatively (p < 0.001). All patients presented with significant improvements in pain and function of the shoulder for daily activities after surgery, however, only one patient achieved excellent results. There is no correlation of functional outcome with age, gender and body mass index. There was no infection or neurovascular complication. Discussion:. The biceps transfer provides soft tissue coverage of the humeral head, and restores the superior stability of the shoulder joint. The transferred biceps tendon also improves the mechanics and increases the compression force of the humeral head to the glenoid fossa. The results of the current study showed significant pain relief and improvement of shoulder function after biceps tendon transfer for irreparable rotator cuff tear. Conclusion:. Biceps tendon transfer is effective in the management of massive irreparable rotator cuff tear. The procedure is technically accessible with minimal surgical risks