https://doi.org/10.46889/JOSR.2023.4107 https://athenaeumpub.com/journal-of-orthopaedic-science-and-research/ Review Article Systematic Review of Lesser Tuberosity Osteotomy Techniques, Outcomes and Biomechanical Testing Parameters: A Critical Appraisal Trevor Ottofaro 1 , Suvleen K Singh 1 , Richard J Friedman 1 , Josef K Eichinger 1* 1 Department of Orthopaedics and Physical Medicine, Medical University of South Carolina, Charleston, United States *Correspondence author: Josef K Eichinger, Professor of Orthopaedics, Department of Orthopaedics and Physical Medicine, Medical University of South Carolina, Charleston, United States; Email: eichinge@musc.edu Abstract Background: Given that optimization of management of the subscapularis is essential to ensuring an optimal outcome after shoulder arthroplasty, this review will focus on the ideal method of Lesser Tuberosity Osteotomy (LTO) repair and the methods by which this is assessed. Specifically, we will review the existing literature to determine how suture configuration, number of sutures, type of sutures, and osteotomy size all influence the biomechanics of an LTO repair. Methods: A systematic review was performed in which one reviewer searched PubMed to find studies analyzing biomechanical strength of lesser tuberosity osteotomy repairs after a total shoulder arthroplasty. The following keywords were used to retrieve articles: (biomechanical) and (Lesser Tuberosity Osteotomy) or (LTO) or (subscapularis repair) and (total shoulder). Results: Nine studies met inclusion criteria. LTO was the strongest, most durable repair in most biomechanical studies. However, the biomechanical testing protocols and repair techniques widely varied throughout the literature. Dual row repair with sutures wrapped around the stem as well thin LTO fragments showed superior biomechanical outcomes. There has been minimal literature focusing on how the number, size and type of suture utilized in a repair affect biomechanical outcomes. Discussion: While the LTO repair technique has been demonstrated in multiple studies to be a biomechanically superior method of subscapularis repair in the setting of TSA, there has not been a single study which has analyzed the effects of repair technique, osteotomy size, as well as suture number/type/size using a standardized biomechanical testing protocol. Level of Evidence: Level I; Biomechanics Keywords: Subscapularis; Lesser Tuberosity Osteotomy (LTO); Total Shoulder Arthroplasty (TSA); Biomechanics; Repair; Strength Abbreviation LTO: Lesser Tuberosity Osteotomy; TSA: Total Shoulder Arthroplasty; ST: Subscapular Tenotomy; MTS: Materials Testing Systems Introduction Total Shoulder Arthroplasty (TSA) is an increasingly common surgical procedure. Over the past 10 years, multiple studies have shown that the number of total shoulder arthroplasties increased by 89% [1]. A key portion of shoulder arthroplasty is release of subscapularis to allow for adequate exposure and in turn appropriate component positioning. There are multiple techniques described for subscapularis release since the advent of TSA. In 1974, Neer, et al., first described subscapularis mobilization via a Subscapular Tenotomy (ST) [2]. This involved a tenotomy 1 cm medial to its insertion on the Lesser Tuberosity (LT) with subsequent end to end repair. However, there was concern regarding subscapularis dysfunction. One of the first research studies addressing potential complications was Miller et al reporting abnormal results in 67.5% liftoff and 66% of belly press Citation: Eichinger JK, et al. Systematic Review of Lesser Tuberosity Osteotomy Techniques, Outcomes and Biomechanical Testing Parameters: A Critical Appraisal. J Ortho Sci Res. 2023;4(1):1-10. https://doi.org/10.46889/JOSR.2023. 4107 Received Date: 07-03-2023 Accepted Date: 31-03-2023 Published Date: 07-04-2023 Copyright: © 2023 by the authors. Submitted for possible open access publication under the terms and conditions of the Creative Commons Attribution (CCBY) license (https://creativecommons.org/li censes/by/4.0/).