Glenoid Track Revisited.

The risk of Hill-Sachs lesion (HSL) to cause instability depends not only on the HSL but also on the glenoid size. Clinically, the only method to assess the risk of instability considering the dynamic interaction of both, the HSL together with the glenoid bone loss, is the glenoid track concept. Since it was introduced in a cadaveric study, its clinical efficacy and validity have been reported in the literature. Sometimes, the medial margin of the footprint (lateral margin of the glenoid track) is difficult to identify when a HSL is overriding the footprint. In such cases, we propose a method to draw an imaginary line connecting two landmarks. Although 3D-CT is the most accurate and widely used method to assess on/off-track lesions, our interest gradually is shifting towards MRI, which has no radiation concern. The current MR method is still under way. There are various risk factors influencing the recurrent instability after surgery. The glenoid track concept deals with only one of these factors, i.e., instability caused by bony lesions. Therefore, the following two issues are important: 1) how to assess the glenoid track precisely and 2) how to incorporate other risk factors into consideration. The former can be achieved by obtaining the custom-made glenoid track width using not the fixed value of 83%, but more individualized value obtained by measuring the active horizontal extension angle of the opposite shoulder in the sitting position. At the same time, the gray zone (peripheral-track lesion) needs to be clearly defined. The latter can be achieved by incorporating the risk factors other than the bony lesions. One example is the glenoid track instability management score (GTIMS), a combination of the glenoid track concept and the instability severity index (ISI) score. This new scoring system is expected to increase the predictive potential of the scoring system, and accordingly to enhance clinical decision making.

Optimizing Muscle-Tendon Lengths in Reverse Total Shoulder Arthroplasty: Evaluation of Surgical and Implant-Design-Related Parameters.

BACKGROUND: Optimizing the function of muscles that cross the glenohumeral articulation in reverse total shoulder arthroplasty (RTSA) is controversial. The current study used a geometric model of the shoulder to systematically examine surgical placement and implant-design parameters to determine which RTSA configuration most closely reproduces native muscle-tendon lengths of the deltoid and rotator cuff. METHODS: A geometric model of the glenohumeral joint was developed and adjusted to represent small, medium, and large shoulders. Muscle-tendon lengths were assessed for the anterior deltoid, middle deltoid, posterior deltoid, and supraspinatus from 0 to 90° of scaption; for the subscapularis from 0° to 60° of internal rotation (IR) and 0° to 60° of scaption; for the infraspinatus from 0° to 60° of external rotation (ER) and 0° to 60° of scaption; and for the teres minor from 0° to 60° of ER at 90° of scaption. RTSA designs were virtually implanted using the following parameters: (1) surgical placement with a centered or inferior glenosphere position and a humeral offset of 0, 5, or 10 mm relative to the anatomic neck plane, (2) implant design involving a glenosphere size of 30, 36, or 42 mm, glenosphere lateralization of 0, 5, or 10 mm, and humeral neck-shaft angle of 135°, 145°, or 155°. Thus, 486 RTSA-shoulder size combinations were analyzed. Linear regression assessed the strength of association between parameters and the change in each muscle-tendon length from the native length. RESULTS: The configuration that most closely restored anatomic muscle-tendon lengths in a small shoulder was a 30-mm glenosphere with a centered position, 5 mm of glenoid lateralization, 0 mm of humeral offset, and a 135° neck-shaft angle. For a medium shoulder, the corresponding combination was 36 mm, centered, 5 mm, 0 mm, and 135°. For a large shoulder, it was 30 mm, centered, 10 mm, 0 mm, and 135°. The most important implant-design parameter associated with restoration of native muscle-tendon lengths was the neck-shaft angle, with a 135° neck-shaft angle being favored (ß = 0.568 to 0.657, p < 0.001). The most important surgical parameter associated with restoration of native muscle-tendon lengths was humeral offset, with a humeral socket placed at the anatomic neck plane being favored (ß = 0.441 to 0.535, p < 0.001). CONCLUSIONS: A combination of a smaller, lateralized glenosphere, a humeral socket placed at the anatomic neck plane, and an anatomic 135° neck-shaft angle best restored native deltoid and rotator cuff muscle-tendon lengths in RTSA. CLINICAL RELEVANCE: This study of surgical and implant factors in RTSA highlighted optimal configurations for restoration of native muscle-tendon lengths of the deltoid and rotator cuff, which has direct implications for surgical technique and implant selection. Additionally, it demonstrated the most influential surgical and implant factors with respect to muscle-tendon lengths, which can be used to aid intraoperative decision-making.

A high level of scientific evidence is available to guide treatment of primary shoulder stiffness: The SIAGASCOT consensus.

PURPOSE: Shoulder stiffness (SS) is a condition characterised by active and passive restricted glenohumeral range of motion, which can occur spontaneously in an idiopathic manner or be associated with a known underlying aetiology. Several treatment options are available and currently no consensus has been obtained on which treatment algorithm represents the best choice for the patient. Herein we present the results of a national consensus on the treatment of primary SS. METHODS: The project followed the modified Delphi consensus process, involving a steering, a rating and a peer-review group. Sixteen questions were generated and subsequently answered by the steering group after a thorough literature search. A rating group composed by professionals specialised in the diagnosis and treatment of shoulder pathologies rated the question-answer sets according to the scientific evidence and their clinical experience. RESULTS: Recommendations were rated with an average of 8.4 points out of maximum 9 points. None of the 16 answers received a rating of less than 8 and all the answers were considered as appropriate. The majority of responses were assessed as Grade A, signifying a substantial availability of scientific evidence to guide treatment and support recommendations encompassing diagnostics, physiotherapy, electrophysical agents, oral and injective medical therapies, as well as surgical interventions for primary SS. CONCLUSIONS: A consensus regarding the conservative and surgical treatment of primary SS could be achieved at a national level. This consensus sets basis for evidence-based clinical practice in the management of primary SS and can serve as a model for similar initiatives and adaptable guidelines in other European countries and potentially on a global scale. LEVEL OF EVIDENCE: Level I.

Postoperative Radiographic Outcomes Following Primary Open Coracoid Transfer (Bristow-Latarjet) Vary in Definition, Classification, and Imaging Modality: A Systematic Review.

PURPOSE: To analyze radiographic outcomes by conventional radiography, computed tomography (CT), or both and complication rates of open coracoid transfer at a minimum of 12-months follow-up. METHODS: A literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using PubMed, Medline (Ovid), and EMBASE library databases. Inclusion criteria were clinical studies reporting on open Latarjet as the primary surgical procedure(revision coracoid transfer after failed prior stabilization excluded) with postoperative radiographic outcomes at a minimum mean 1-year follow-up. Patient demographics, type of postoperative imaging modality, and radiographic outcomes and complications including graft union, osteoarthritis, and osteolysis were systematically reviewed. Data were summarized as ranges of reported values for each outcome metric. Each radiographic outcome was graphically represented in a Forest plot with point estimates of the incidence of radiographic outcomes with corresponding 95% confidence intervals and I2. RESULTS: Thirty-three studies met inclusion criteria, with a total of 1,456 shoulders. The most common postoperative imaging modality was plain radiography only (n = 848 [58.2%]), both CT and radiography (n = 287 [19.7%]), and CT only (n = 321 [22.1%]). Overall, the reported graft union rate ranged from 75% to 100%, of which 79.8% (n = 395) were detected on plain radiography. The most common reported postoperative radiographic complications after the open coracoid transfer were osteoarthritis (range, 0%-100%, pooled mean 28%), graft osteolysis (range, 0%-100%, pooled mean 30%), nonunion (range, 0%-32%, pooled mean 5.1%), malpositioned graft (range, 0%-75%, pooled mean 14.75%), hardware issues (range, 0%-9.1%, pooled mean 5%), and bone block fracture (range, 0%-8%, pooled mean 2.1%). Graft healing was achieved in a majority of cases (range, 75%-100%). CONCLUSION: Postoperative radiographic outcomes after open coracoid transfer vary greatly in definition, classification, and imaging modality of choice. Greater consistency in postoperative radiographic outcomes is essential to evaluate graft healing, osteolysis, and nonunion. LEVEL OF EVIDENCE: Level IV, systematic review of Level III-IV studies.

Operational strategies to deal with the COVID-19 emergency: recommendations from the Italian national society SIAGASCOT following the introduction of vaccines against the SARS-CoV-2 infection.

BACKGROUND: This article aims to present the operational recommendations adopted by the Italian national society for orthopaedic surgery, arthroscopy, and sports medicine (SIAGASCOT) in managing patients eligible to undergo elective orthopaedic surgery during the COVID-19 pandemic after the beginning of a national vaccination campaign. MATERIALS AND METHODS: An extensive literature search, analysing medical databases and scientific societies protocols, was performed to support this document. A four-step approach was used: 1-definition of priorities; 2-definition of significant clusters of interventions; 3-extraction of recommendations from international literature; and 4-adaptation of the recommendations to the specific features of the Italian healthcare system. RESULTS: Three operational priorities were defined ("continuity of care and containment of the virus spread", "examination of waiting lists", and "definition of the role of vaccines"), six significant clusters of intervention were identified, and recommendations regarding the risk management for healthcare staff and hospital facility as well as the preoperative, in-hospital, and postoperative management were produced. Patient selection, preoperative screening, and pre-hospitalization procedures, which are regarded as pivotal roles in the safe management of patients eligible to undergo elective orthopaedic surgery, were analysed extensively. CONCLUSIONS: This document presents national-wide recommendations for managing patients eligible to undergo elective orthopaedic surgery with the beginning of the vaccination campaign. This paper could be the basis for similar documents adapted to the local healthcare systems in other countries. LEVEL OF EVIDENCE: Level IV.

Impact of reverse shoulder arthroplasty design and patient shoulder size on moment arms and muscle fiber lengths in shoulder abductors.

BACKGROUND: Reverse shoulder arthroplasty (RSA) increases the moment arm of the deltoid; however, there is limited knowledge on the accompanying changes in muscle architecture that play a role in muscle force production. The purpose of this study was to use a geometric shoulder model to evaluate the anterior deltoid, middle deltoid, and supraspinatus regarding (1) the differences in moment arms and muscle-tendon lengths in small, medium, and large native shoulders and (2) the impact of 3 RSA designs on moment arms, muscle fiber lengths, and force-length (F-L) curves. METHODS: A geometric model of the native glenohumeral joint was developed, validated, and adjusted to represent small, medium, and large shoulders. Moment arms, muscle-tendon lengths, and normalized muscle fiber lengths were assessed for the supraspinatus, anterior deltoid, and middle deltoid from 0° to 90° of abduction. RSA designs were modeled and virtually implanted, including a lateralized glenosphere with an inlay 135° humeral component (lateral glenoid-medial humerus [LGMH]), a medialized glenosphere with an onlay 145° humeral component (medial glenoid-lateral humerus [MGLH]), and a medialized glenosphere with an inlay 155° humeral component (medial glenoid-medial humerus [MGMH]). Descriptive statistics were used to compare moment arms and normalized muscle fiber lengths. RESULTS: As shoulder size increased, the moment arms and muscle-tendon lengths for the anterior deltoid, middle deltoid, and supraspinatus increased. All RSA designs achieved greater moment arms for the anterior and middle deltoid, with the MGLH design achieving the largest increase. The resting normalized muscle fiber length of the anterior and middle deltoid was substantially increased in the MGLH (1.29) and MGMH (1.24) designs, shifting the operating ranges of these muscles to the descending portions of their F-L curves, whereas the LGMH design maintained a resting deltoid fiber length (1.14) and operating range similar to the native shoulder. All RSA designs demonstrated a decrease in the native supraspinatus moment arm in early abduction, with the largest decrease in the MGLH design (-59%) and minimal decrease in the LGMH design (-14%). The supraspinatus operated on the ascending limb of its F-L curve in the native shoulder and remained on this portion of the F-L curve for all RSA designs. CONCLUSION: Although the MGLH design maximizes the abduction moment arm for the anterior and middle deltoid, overlengthening of the muscle may compromise deltoid muscle force production by forcing the muscle to operate on the descending portion of its F-L curve. In contrast, the LGMH design increases the abduction moment arm for the anterior and middle deltoid more modestly while allowing the muscle to operate near the plateau of its F-L curve and maximizing its force-producing potential.

Reverse shoulder arthroplasty: State-of-the-art.

The reverse shoulder arthroplasty conceived by Paul Grammont in 1985 has gradually gained popularity as a treatment for multiple shoulder diseases. Unlike previous reverse shoulder prosthesis characterized by unsatisfactory results and a high glenoid implant failure rate, the Grammont design has immediately shown good clinical outcomes. This semi constrained prosthesis solved the issues of the very first designs by medializing and distalizing the center of rotation with an increased stability of the replacement of the component. The indication was initially limited to cuff tear arthropathy (CTA). It has then been expanded to irreparable massive cuff tears and displaced humeral head fractures. The most frequent problems of this design are a limited postoperative external rotation and scapular notching. Different modifications to the original Grammont design have been proposed with the aim of decreasing the risk of failure and complications and improving the clinical outcomes. Both the position and version/inclination of the glenosphere and the humeral configuration (e.g. neck shaft angle) influence the RSA outcomes. A lateralized glenoid (whether with bone or metal) and a 135° Inlay system configuration leads to a moment arm which is the closest to the native shoulder. Clinical research will focus on implant designs reducing bone adaptations and revision rate, strategies to prevent more effectively infections. Furthermore, there is still room for improvement in terms of better postoperative internal and external rotations and clinical outcomes after RSA implanted for humeral fracture and revision shoulder arthroplasty.

Depression, fear of re-injury and kinesiophobia resulted in worse pain, quality of life, function and level of return to sport in patients with shoulder instability: a systematic review.

INTRODUCTION: Maladaptive psychological responses may hinder participation and return to pre-injury level in sport. The aim of this study was to investigate the psychological factors influence on pain, function, quality of life and time to return to sport in subjects with shoulder instability. EVIDENCE ACQUISITION: The research was conducted until the 15th of May 2022 in MEDLINE, CENTRAL, PEDro, and PubPSYCH regardless language, publication status or date. We included adults (≥16 years old) with shoulder instability. Quality assessment was performed using Joanna Briggs Institute Critical Appraisal tools. EVIDENCE SYNTHESIS: Three papers, 270 participants, met the inclusion criteria. Subjects with preoperative depression demonstrated worse 1-year postoperative shoulder-related quality of life score than the cohort without depression. Shoulder function had a weak negative correlation with depression. Pain intensity and depression showed a positive correlation of moderate strength. Fear of re-injury correlated with SPADI total, pain and function; moreover, it increased the likelihood of recurrent dislocation in multivariate analysis. Kinesiophobia at baseline correlated with WOSI. CONCLUSIONS: Depression, fear of re-injury and kinesiophobia correlate with pain, function, quality of life and return to sport in people with shoulder instability. We recommend a multi-professional approach to integrate the psychological standpoint in rehabilitation treatment to maximize quality of life and function in subjects with instability.

Surgical guides for flapless dental implant placement and immediate definitive prosthesis installation by using selective laser melting and sintering for 3D metal and polymer printing: A clinical report.

Integration between the phases of computer-based guided dental implant surgery can be used to optimize oral rehabilitation. Two new surgical guides prepared by using the 3D metal and polymer printing technology are presented for immediate implant loading and definitive fixed prosthesis construction in flapless dental implant surgery. Nine implants and 2 fixed prostheses were installed in 2 completely edentulous adult patients by using a metallopolymer surgical guide with a metal central bar attached to a polymer seal or a metal guide. Virtual planning was used to design the 3D-printed surgical guides, which were then constructed by using selective laser sintering (SLM) and selective laser melting (SLS). The 3D-printed surgical guides oriented the surgical placement of the implants and were welded to the abutments and attached to the denture framework. The technique allowed implants and prostheses to be installed on the same day.

Depression and Anxiety Are Associated With Worse Subjective and Functional Baseline Scores in Patients With Frozen Shoulder Contracture Syndrome: A Systematic Review.

Purpose: To investigate whether psychological factors, such as avoidance behavior, fear, pain catastrophization, kinesiophobia, anxiety, depression, optimism, and expectation are associated with different subjective and functional baseline scores in patients with frozen shoulder contracture syndrome (FSCS). Methods: Searches were conducted in MEDLINE, Cochrane Library (CENTRAL Database), PEDro, Pubpsych, and PsychNET.APA without restrictions applied to language, date, or status of publication. Two authors reviewed study titles, abstract, and full text based on the following inclusion criteria: adult population (≥ 30 < 70 years old) with FSCS. Results: Seven hundred and seventy-six records were included by the search strategies. After title final screening, 6 studies were included for the qualitative synthesis. Psychological features investigated were anxiety, depression, pain-related fear, pain catastrophizing, and pain self-efficacy; reported outcomes included pain, function, disability, quality of life, and range of motion. Data suggest that anxiety and depression impact self-assessed function, pain, and quality of life. There is no consensus on the correlation between psychological variables and range of motion. Associations were suggested between pain-related fear, pain-related beliefs, and pain-related behavior and perceived arm function; pain-related conditions showed no significant correlation with range of motion and with perceived stiffness at baseline. Conclusion: Scores traditionally thought to assess physical dimensions like shoulder pain, disability, and function seem to be influenced by psychological variables. In FSCS patients, depression and anxiety were associated with increased pain perception and decreased function and quality of life at baseline. Moreover, pain-related fear and catastrophizing seem to be associated with perceived arm function.

The Use of Scapular Bone Flaps During Head-and-Neck Reconstruction: Functional, Orthopedic, and Quality of Life Analyses of Flap-Harvest-Related Deficits.

ABSTRACT: The authors sought correlations between harvesting of the scapular bone tip free flap used for head-and-neck reconstruction and any shoulder function deficit, particularly at the level of the rotator cuff. The flap permits reconstruction of large and diverse regions of the head and neck, but long-term harvest morbidity has not been investigated extensively. The authors analyzed the clinical records of all patients who underwent head-and-neck reconstructions using free scapular tip flaps in our department over the past 5 years. The inclusion criteria were complete clinical and radiological documentation and follow-up for at least 12 months. Two populations, a surgical and control population, were analyzed. All patients in both populations underwent the simple shoulder test, an internationally validated self-administered test that highlights functional shoulder deficits, and 3 additional tests at orthopedic visits: the external rotation test, Patte test, and external rotation lag sign test. A head-and-neck cancer-specific questionnaire (University of Washington Quality of Life, version 4) was completed by the surgical patients. All statistical analyses were performed using Software IBM SPSS Statistics (IBM Corp., Armonk, NY).A total of 19 patients met the inclusion criteria: 11 males (57.8%) and 8 females (42.2%) of mean age 60.9 years (range 23-75 years). In addition, 20 age-and sex-matched volunteers with no history of shoulder pathology were evaluated in terms of shoulder functionality. The average score on the simple shoulder test was 10.55 in the healthy population versus 8.31 in the study population ( P < 0.001); in particular, shoulder strength differed between the groups. Similarly, the orthopedic examinations revealed clinically significant differences between the controls and patients on the Patte test and external rotation lag sign test (both P < 0.001), but not the external rotation test ( P > 0.001). The mean University of Washington Quality of Life was 73.39; most patients reported good quality of life (52.6%), followed by very good (15.7%).The free scapular bone tip flap is valuable for reconstruction of head-and-neck defects; the long and reliable vascularpedicle allows rapid patient mobilization. Morbidity was confined to small reductions in shoulder strength and external rotation, which do not affect quality of life.

Accuracy Evaluation of the Computer-Designed Selective Laser Sintering Surgical Guide for Flapless Immediate Loading Dental Implants Surgery in Edentulous Jaws.

This study was designed to evaluate the accuracy of a novel computer-designed and selectively laser sintered surgical guide for flapless dental implant placement in the edentulous jaw. Fifty dental implants were placed in 11 patients with at least 1 totally edentulous jaw. Initially, cone-beam computed tomography (CBCT) was performed in each patient to define the virtual position of the dental implants based on the assessment of bone availability and the proposed dental prosthesis. After virtual planning, 3D surgical guides were printed using selective laser sintering. CBCT was repeated after the surgery, and the pre- and postoperative images were overlapped in computer-assisted design software to compare the planned and actual positions of the dental implants using a 1-sample t test. The mean ± angular standard deviation between the long axes of the planned and final dental implant positions was 4.58° ± 2.85°; the linear deviation in the coronal position was 0.87 ± 0.49 mm and in the apical region of the dental implants was 1.37 ± 0.69 mm. These differences were statistically significant (P < .001). The proposed modifications reduced the deviations, resulting in an improvement in the technique. We were able to place implants and temporary prostheses using the present protocol, taking into account the differences between the planned and final positions of the dental implants.

Return to sport after reverse total shoulder arthroplasty is highly frequent: a systematic review.

IMPORTANCE: One of the most frequent concerns of the increasing number of patients undergoing shoulder arthroplasty is the possibility to resume sport after surgery. OBJECTIVE: The aim of this systematic review was to determine the rate of return to sport after reverse total shoulder arthroplasty (RSA) and the subjective level of performance. EVIDENCE REVIEW: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to perform this systematic review. A systematic electronic search was performed using the PubMed (MEDLINE), Embase and Cochrane Library databases. All the studies analysing the rates were pooled; data were extracted and statistically analysed. The eligibility criteria were studies with at least 20 adult patients recruited. All studies had to relate return to sports after RSA. FINDINGS: A total of six studies were included for a total of 457 patients. Mean age and average follow-up were, respectively, 74.7 years (range 33-88 years) and 3.6 years (range 1-9.4 years). The mean rate of return to sport ranged from 60% to 93%. The mean time for resuming sports was 5.3 months. The overall rate of return to sport after reverse shoulder arthroplasty was 79%. The mean level of sports at the time of the survey was worsened in 7.9%, improved in 39.6% and had no change in 55.2% of the cases. CONCLUSIONS AND RELEVANCE: Based on the current available data, return to sports after reverse shoulder arthroplasty is possible and highly frequent. The subjective level of practice undergoes no change or improves in most of the cases. More studies and better-designed trials are needed in order to enrich the evidence on specific sports recovery after the procedure. LEVEL OF EVIDENCE: IV.

New Trends in Shoulder Surgery from Biomechanics to the Operating Room.

After a rigorous peer review process, twelve papers were accepted and published [...].

Evaluation and Management of Glenohumeral Instability With Associated Bone Loss: An Expert Consensus Statement Using the Modified Delphi Technique.

PURPOSE: To establish an international expert consensus, using the modified Delphi technique, on the evaluation and management of glenohumeral instability with associated bone loss. METHODS: A working group of 6 individuals generated a list of statements related to history and physical examination, imaging and specialized diagnostic tests, bone loss quantification and classification, treatment outcomes and complications, and rehabilitation for the management of glenohumeral instability associated with bone loss to form the basis of an initial survey for rating by a group of experts. The expert group (composed of 22 high-volume glenohumeral instability experts) was surveyed on 3 occasions to establish a consensus on the statements. Items with over 70% agreement and less than 10% disagreement achieved consensus. RESULTS: After a total of 3 rounds, 31 statements achieved consensus. Eighty-six percent of the experts agreed that a history of multiple dislocations and failed soft-tissue surgery should raise suspicion about the possibility of an associated bone deficit. Ninety-five percent of the experts agreed that 3-dimensional (3D) computed tomography (CT) is the most accurate diagnostic method to evaluate and quantify bone loss. Eighty-six percent of the experts agreed that any of the available methods to measure glenoid bone deficiency is adequate; however, 91% of the experts thought that an en face view of the glenoid using 3D CT provides the most accurate method. Ninety-five percent of the experts agreed that Hill-Sachs lesions are poorly quantified and classified by current imaging systems. Ninety percent of the experts agreed that in cases with a glenoid bone deficit greater than 20%, glenoid bone graft reconstruction should be performed and any of the available options is valid. There was no consensus among experts on how Hill-Sachs injuries should be managed or on how postoperative rehabilitation should be carried out. CONCLUSIONS: The essential statements on which the experts reached consensus included the following: A history of multiple dislocations and failed soft-tissue surgery should make surgeons consider the possibility of an associated bone deficit. Three-dimensional CT is the most accurate diagnostic method to evaluate and quantify bone loss. Although any of the available methods to measure glenoid bone deficiency is adequate, an en face view of the glenoid using 3D CT provides the most accurate method. Hill-Sachs lesions are poorly quantified and classified by current imaging systems. Finally, in cases with a glenoid bone deficit greater than 20%, glenoid bone graft reconstruction should be performed. LEVEL OF EVIDENCE: Level V, consensus statement.

Limited Predictive Value of the Instability Severity Index Score: Evaluation of 217 Consecutive Cases of Recurrent Anterior Shoulder Instability.

PURPOSE: To review the existing variables and their ability to predict recurrence of shoulder instability as it relates to the Instability Severity Index Score (ISIS), as well as evaluate any other pertinent imaging and patient history variables that may impact risk of recurrent anterior instability after arthroscopic Bankart repair. METHODS: All consecutive patients with recurrent anterior shoulder instability and who had arthroscopic instability repair were identified. Exclusion criteria were prior surgery on the shoulder, posterior or multidirectional instability, instability caused by seizure disorder, or a rotator cuff tear. All ISIS variables were recorded (age <20 years, sport type and level, hyperlaxity, Hill-Sachs on anteroposterior external rotation radiograph, loss of glenoid contour on anteroposterior radiograph), as well as additional variables: (1) number of instability events; (2) total time of instability; (3) glenoid bone loss (GBL) percent; and (4) Hill-Sachs measures (H/L/W/D/Volume). Postoperative outcomes were assessed based on the Western Ontario Shoulder Instability Index (WOSI), Single Assessment Numeric Evaluation (SANE) scores, and American Shoulder and Elbow Surgeons (ASES) scores, and recurrent anterior instability. Regression analysis was used to determine preoperative variables that predicted outcomes and failures. RESULTS: There were 217 consecutive patients (209 male patients [96.5%], 8 female patients [3.5%]) who met the inclusion criteria and were all treated with a primary arthroscopic shoulder stabilization during a 3.5-year period (2007-2011), with a mean follow-up time of 42 months (range, 26-58). The mean age at first instability event was 23.9 years (range, 16-48 years) and the mean cumulative ISIS score for the overall group was 3.6 (range, 1-6). Outcomes were improved from mean preoperative (WOSI = 1,050/2,100; ASES = 61.0; SANE = 52.5) to postoperative (WOSI = 305/2,100; ASES = 93.5; SANE = 95.5). A total of 11.5% (25/217) of patients had evidence of recurrent instability (subluxation or dislocation). Additionally, all 25 patients who failed postoperatively also had consistently inferior ASES, SANE, and WOSI outcome scores when compared with successfully treated patients. Factors associated with failure were GBL greater than 14.5% (P < .001), total time of instability symptoms greater than 3 months (P = .03), Hill-Sachs volume greater than 1.3 cm3 (P = .02), contact sports participation (P = .05), and age 20 years or younger (P < .01). There was no correlation in outcomes with Hill-Sachs on presence of glenoid contour loss on radiograph (P = .07), participation sports, or ISIS (mean = 3.4 success vs 3.9 failure, P > .05). CONCLUSIONS: At a mean follow-up of 42 months was an 11.5% failure rate after arthroscopic Bankart stabilization surgery. This study shows no correlation between treatment outcome and the ISIS measure, given a mean score of 3.4 for the overall cohort with little difference identified in those who failed. However, several important parameters previously unidentified were detected including, GBL greater than 14.5%, Hill-Sachs volume greater than 1.3 cm3, and duration of instability symptoms (>3 months). The ISIS may need to be redesigned to incorporate variables that more accurately portray the actual risk of failure after arthroscopic stabilization, including quantification of both glenoid and humeral head bone loss. LEVEL OF EVIDENCE: III (Retrospective Case Series).

Measuring Bone Loss in the Unstable Shoulder: Understanding and Applying the Track Concept.

An interesting international debate has been developed over the past 10 years (the last decade) surrounding the surgical procedure for recurrent anteroinferior instability and a definitive consensus is lacking on the factors which favor one technique over another, especially when bone loss is present (soft tissue vs. bone block). Glenoid bone loss is commonly observed in the shoulder with anterior instability, and it is difficult to evaluate the shape of the glenoid using plain radiograph, therefore, computed tomography or intraoperative observation is recommended for accurate assessment of glenoid bone loss and Hill-Sachs lesion. When we consider the bony defect of the glenoid as a risk factor for surgical failure, it is crucial to take into consideration the features of a concomitant Hill-Sachs lesion. However, all the previous reports focusing on the size of the Hill-Sachs lesion or on the glenoid bone loss in isolation, overlook the interaction of the 2 lesions through the arc of range of motion and how this may influence instability. The glenoid track is the first model to determine, in a dynamic way, how bone loss on both sides of the joint can lead to instability. The glenoid track is a zone of contact created by the glenoid on the humeral articular surface when the arm is moved along the end-range of motion (abduction and external rotation). The use of the glenoid track concept can potentially help guide surgical decision-making.

Risk Factors for Recurrent Anterior Glenohumeral Instability and Clinical Failure Following Primary Latarjet Procedures: An Analysis of 344 Patients.

BACKGROUND: Patients with a greater risk of recurrent instability and inferior clinical outcomes following a primary Latarjet procedure can be preoperatively identified on the basis of clinical, radiographic, and demographic criteria. The purpose of this study was to identify risk factors influencing the rates of recurrent anterior glenohumeral instability and clinical failure following a primary Latarjet procedure. METHODS: All patients who underwent a primary Latarjet procedure were prospectively enrolled and evaluated. The Western Ontario Shoulder Instability Index (WOSI) and Single Assessment Numeric Evaluation (SANE) outcome scores were collected at a minimum 5-year follow-up along with evidence of recurrent instability. Recurrent instability (recurrent subluxation or dislocation) was considered as a failure. Clinical failure was defined as a postoperative WOSI score of ≥630 points (≤70% normal) or a SANE score of ≤70 points. RESULTS: From 2004 to 2014, 344 patients (358 shoulders) with a mean age of 30.6 years (range, 16 to 68 years) were enrolled and had a mean follow-up time of 75 months (range, 61 to 89 months). The median postoperative WOSI score was 265 points (range, 0 to 1,100 points), and the median SANE score was 88 points (range, 50 to 100 points). Recurrence occurred in 17 shoulders (4.7%), 5 with dislocation and 12 with subluxation; and 28 (8.2%) of 341 shoulders without recurrent instability were clinical failures following a Latarjet procedure. The risk factors for recurrence included atraumatic dislocation (odds ratio [OR], 4.6; p < 0.01) and bilateral instability (OR, 4.0; p = 0.01), whereas the risk factors for clinical failure (WOSI score of ≥630 points or SANE score of ≤70 points) were female sex (OR, 2.8; p < 0.01) and bilateral instability (OR, 4.6; p = 0.01). CONCLUSIONS: Outcomes at a mean of >6 years following a primary Latarjet procedure for anterior shoulder instability were very good, with an overall recurrence rate of 4.7%. An additional 8.2% of cases were defined as clinical failures. Patients with an atraumatic mechanism of primary dislocation, bilateral instability, and female sex were identified to be at a greater risk of recurrence or clinical failure. Although additional work is necessary, patients with capsuloligamentous laxity, relatively atraumatic instability history, bilateral instability, and female sex may be preoperatively identified as having a higher risk of treatment failure after a primary Latarjet procedure. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical Analysis of Plate Fixation Compared With Various Screw Configurations for Use in the Latarjet Procedure.

BACKGROUND: The biomechanical properties of coracoid fixation with a miniplate during the Latarjet procedure have not been described. PURPOSE: To determine the biomechanical properties of miniplate fixation for the Latarjet procedure compared with various screw fixation configurations. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 8 groups (n = 5 specimens per group) were tested at a screw insertion angle of 0°: (1) 3.75-mm single screw, (2) 3.75-mm double screw, (3) 3.75-mm double screw with washers, (4) 3.75-mm double screw with a miniplate, (5) 4.00-mm single screw, (6) 4.00-mm double screw, (7) 4.00-mm double screw with washers, and (8) 4.00-mm double screw with a miniplate. In addition, similar to groups 1 to 3 and 5 to 7, there were 30 additional specimens (n = 5 per group) tested at a screw insertion angle of 15° (groups 9-14). To maintain specimen uniformity, rigid polyurethane foam blocks were used. Testing parameters included a preload of 214 N for 10 seconds, cyclical loading from 184 to 736 N at 1 Hz for 100 cycles, and failure loading at a rate of 15 mm/min until 10 mm of displacement or specimen failure occurred. RESULTS: All single-screw constructs and 77% of 15° screw constructs failed before the completion of cyclical loading. Across all groups, group 8 (4.00-mm double screw with miniplate) demonstrated the highest maximum failure load (P < .001). There were no differences in failure loads among specimens with single-screw fixation (groups 1, 5, 9, and 12; P > .05). All specimens in groups 9, 10, 11, 12, 13, and 14 (insertion angle of 15°) had significantly lower maximum failure loads compared with specimens in groups 2, 3, 4, 6, 7, and 8 (insertion angle of 0°) (P < .001 for all). CONCLUSION: These results indicate significantly superior failure loads with the miniplate compared with all other constructs. Across all fixation techniques and screw sizes, constructs with screws inserted at 0° performed better than constructs with screws inserted at 15°. CLINICAL RELEVANCE: The use of a miniplate for coracoid fixation during the Latarjet procedure may provide a more durable construct for the high-demand contact athlete.

Editorial Commentary: Latarjet Mechanics and Biology: Thinking in Biodynamic Fashion.

Latarjet technique via open or arthroscopic approach is a very complex surgery that includes several steps. The coracoid placement that is performed at the end of this procedure represents the key point to avoid complications and attain the best clinical results. Mechanics and biology need to work as a whole to improve the integration of the graft on the glenoid neck.