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Background: Only a few articles describe the reproducibility and clinical feasibility of glenoid inclination measurements on conventional radiographs, and none of them validated their method in shoulder arthroplasty cases. From a clinical point of view, the angle measured between the supraspinatus fossa and the glenoid fossa line (angle β) appears to be the most interesting angle to assess glenoid inclination. This study aimed to validate the angle β in shoulder arthroplasty patients to facilitate the assessment of glenoid component inclination., Materials and Methods: Seventeen patients who underwent total or reverse shoulder arthroplasty were evaluated. The angle β was measured by 2 independent observers on postoperative radiographs and 3-dimensional (3D) models. The interobserver variability and accuracy of angle β were analyzed by calculating the intraclass correlation coefficient (ICC) and by generating Bland-Altman plots., Results: The angle β showed a good interobserver variability (ICC = 0.971 for radiographs, ICC = 0.980 for 3D models) and a good agreement between the radiographic and 3D measurements (ICC = 0.904 for observer 1 and ICC = 0.908 for observer 2). Bland-Altman plots demonstrated that in 95% of the measurements on radiographs, the error will be <10. In the investigated population, 85% showed an error <6., Conclusion: This study demonstrates that angle β can be measured on radiographs to assess glenoid component inclination in total and reverse shoulder arthroplasty, but clinicians and researchers should keep in mind that measurement errors of 10° may occur in a minority of cases., (Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

Background: The aim of this study was to assess the influence of 3-dimensional (3D) preoperative planning and patient-specific instrument (PSI) guidance of glenoid component positioning on its inclination in total shoulder arthroplasty (TSA) and reverse shoulder arthroplasty (RSA)., Materials and Methods: Thirty-six shoulder arthroplasties (12 TSAs, 24 RSAs) were analyzed, of which 18 procedures (6 TSAs, 12 RSAs) were executed using preoperative 3D planning and patient-specific guides to position the central guide pin for glenoid component implantation. In 9 cases, the glenoid anatomy was severely distorted through wear or previous surgery. The inclination of the glenoid component was measured by 2 observers, using the angle between the glenoid baseplate and the floor of the supraspinatus fossa (angle β) on postoperative radiographs., Results: For TSA, the average angle β was 74 ± 9 in the PSI group and 86 ± 12 in the non-PSI group; for RSA, the average angle β was 83 ± 7 in the PSI group and 90 ± 17 in the non-PSI group. Extreme angles β, which represent extreme values of glenoid component inclination, are more likely to occur in the non-PSI group than in the PSI group (P < .001 for TSA; P = .02 for RSA)., Conclusions: The3D preoperative surgical planning and PSI guidance reduce variability in glenoid component inclination and avoid extreme inclination errors for TSA and RSA., (Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.)

The number of shoulder arthroplasty procedures performed in the United States is steadily increasing as a result of an expansion in implant options, clinical indications, and surgical experience. Available options include stemmed implants, short-stemmed or stemless prostheses, fracture-specific designs, resurfacing implants, partial surface replacement, metal-backed or polyethylene glenoid components designed for cementation or bone ingrowth, and reverse total shoulder arthroplasty. Efforts to re-create anatomy, improve outcomes, and avoid complications have resulted in many changes in prosthesis design. Despite these changes, failures still occur, and revision surgery is sometimes necessary. A thorough knowledge of current arthroplasty options, indications, and the principles of implantation is necessary to optimize outcomes after shoulder arthroplasty.

Longevity of total anatomic and reversed shoulder arthroplasty largely depends on accurate correction of glenoid deformity and correct positioning and fixation of the glenoid component. However, the morphology of the scapula is inconsistent, varying degrees of osteoarthritis cause numerous anatomic changes, and standard 2-dimensional imaging and standard surgical instrumentation are imprecise for preoperative planning and execution of glenoid reconstruction. Recently, various authors have shown that preoperative 3-dimensional surgical planning and computer navigation technology may increase the accuracy and repeatability of the implantation of the glenoid component, especially for the position and orientation of the glenosphere and screws in reversed arthroplasty. These novel techniques may allow the surgeon to better define the preoperative deformity, select the optimal implant position, and then accurately execute the plan at the time of surgery. Future studies are needed to determine the long-term effect on functional outcome and cost-effectiveness of computer-assisted technology in shoulder arthroplasty.

Humeral implant design in shoulder arthroplasty has evolved over the years. The third generation shoulder prostheses have an anatomic humeral stem that replicates the 3-dimensional parameters of the proximal humerus. The overall complication rate has decreased as a result of these changes in implant design. In contrast, the rate of periprosthetic humeral fractures has increased. To avoid stem-related complications while retaining the advantages of the third generation of shoulder implants, the stemless total evolutive shoulder system has been developed. The indications, the surgical technique, and the complications of this humeral implant in shoulder arthroplasty will be described.

Hypothesis: In total shoulder arthroplasty, the humeral component, particularly the stem, can be involved in some of the complications and technical difficulties increase in posttraumatic arthritis with proximal humeral malunion. To decrease the intraoperative complications related to the stem, the TESS (Biomet Inc, Warsaw, IN) humeral implant, was designed in 2004 hypothesis that we can obtain a good fixation with a stemless prosthesis. This investigation reports the preliminary results of this prosthesis with more than 3 years of follow-up., Methods: Between March 2004 and June 2005, 70 patients underwent 72 shoulder replacements with the TESS humeral prosthesis. Sixty-three patients were reviewed with a follow-up of more than 36 months (average, 45.2 months; range, 36-51 months). The mean preoperative Constant score was 29.6., Results: Gain in active mobility was 49 degrees for forward flexion and 20 degrees for external rotation. The postoperative Constant score was 75. Radiographic analysis showed no radiolucencies or implant migration. Functional results are comparable with previous reports on prosthetic glenohumeral replacement., Discussion: Our clinical results are similar to this with classical prosthesis. The humeral head removal facilitates the glenoid exposure and implantation. After the initial cases any specific complication was seen., Conclusions: Owing to the automatic central positioning of the implant, an anatomic reconstruction was achieved. In malunions, no tuberosity osteotomy was required. At 3 years of follow-up, there is radiologic evidence of maintained implant stability. These encouraging preliminary results confirm our belief that a stemless prosthesis can be used to obtain an anatomic reconstruction of the proximal humerus. A longer-term follow-up study is needed to validate these results., ((c) 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)