Improved Clinical Outcomes After Lateralized Reverse Shoulder Arthroplasty: A Systematic Review.

BACKGROUND: Lateralized reverse shoulder arthroplasty (RSA) has emerged as an attempt to improve on some of the drawbacks of conventional RSA, such as glenoid notching and decrease in ROM. Although this new design is being used in clinical practice, the evidence is mostly limited to case series and has not been systematically reviewed. QUESTIONS/PURPOSES: (1) How much did patient-reported outcome measures (PROMs) and ROM improve among patients who receive a lateralized RSA implant? (2) What proportion of shoulders experience complications, revision surgery, or scapular notching? METHODS: The PubMed and EMBASE databases were searched from database inception to January 31, 2020. We included clinical studies that reported the PROMs and/or ROM of patients with insufficient rotator cuffs undergoing RSA with a lateralized implant. All other types of studies and those including patients with fractures, instability or escape, infection, rheumatologic disease, neurologic disease, or revision surgeries as an indication for RSA were excluded. PROMs and ROM were collected and are reported as mean values and ranges. Complications, revision surgery, and scapular notching are presented as proportions. The percentage of the mean change relative to the minimum clinically important difference (MCID) was calculated using the anchor-based value for each outcome. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. The initial search yielded 678 studies; 61 full-text articles were analyzed according to our eligibility criteria. After a detailed analysis, we included nine studies that evaluated 1670 patients (68% of whom [1130] were women) with a mean age of 71.8 ± 0.6 years. The mean follow-up period was 41.1 ± 5.6 months. The mean MINORS score was 12 ± 4. RESULTS: Active ROM improved for forward flexion (mean change 47° to 82°; MCID 12°), abduction (mean change 43° to 80°; MCID 7°), external rotation (mean change 8° to 39°; MCID 3°), and internal rotation (mean change -2 to 1 points). PROM scores also improved, including the American Shoulder and Elbow Surgeons score (mean change 20 to 50; MCID 20.9 points), Constant score (mean change 28 to 40; MCID 5.7 points), Simple Shoulder Test score (mean change 3 to 7; MCID 2.4 points), and VAS score (mean change -1.8 to -4.9; MCID -1.6 points). The proportion of shoulders with complications ranged from 0% (0 of 44) to 21% (30 of 140), and the proportion of shoulders with scapular notching ranged from 0% (0 of 76) to 29% (41 of 140). The proportion of patients undergoing revision ranged from 0% (0 of 44) to 13% (10 of 76) at short-term follow-up. CONCLUSION: Lateralized RSA is a reasonable alternative to medialized implants for patients with rotator cuff insufficiency because it might reduce the likelihood of scapular notching without apparently compromising PROMs or ROM. More studies are required to determine whether there is a direct correlation between the amount of lateralization and PROMs or ROM.

Benefits of radial distortion correction in arthroscopic surgery: a first experimental study on a knee model.

BACKGROUND: Lens probes used in arthroscopy typically have a small diameter and wide field-of-view. This introduces strong radial distortion (RD) into the image, ultimately affecting the surgeon's hand-eye coordination. This study evaluates potential benefits of using distortion-free images in arthroscopic surgery. METHODS: Distortion-free images were obtained using RDFixer™ software (Perceive3D, SA) to remove RD in the input video stream. Twelve orthopedic residents performed an arthroscopic task (loose body removal) in a dry-knee model using video with and without distortion. Residents were questioned about image quality, and surgical performance was rated using an adapted Global Rating Scale. RESULTS: A statistically significant improvement of all parameters was observed with distortion-free images. Residents perceived distortion-free images as providing a wider field-of-view and a better notion of relative depth and distance. CONCLUSION: RD correction improved the surgical performance of residents, potentially decreasing their learning curve. Future work will study whether the benefits are observable in experienced surgeons. Copyright © 2014 John Wiley & Sons, Ltd.