Augmentation of a Transosseous-Equivalent Repair in Posterosuperior Nonacute Rotator Cuff Tears With a Bioinductive Collagen Implant Decreases the Retear Rate at 1 Year: A Randomized Controlled Trial.

PURPOSE: To determine whether the addition of a bioinductive collagen implant (BCI) over a transosseous equivalent (TOE) repair of medium-to-large posterosuperior rotator cuff tears improves the healing rate determined by magnetic resonance imaging (MRI) at 12-month follow-up. METHODS: A Level I randomized controlled trial was performed in 124 subjects with isolated, symptomatic, reparable, full-thickness, medium-to-large posterosuperior nonacute rotator cuff tears, with fatty infiltration ≤2. These were randomized to 2 groups in which an arthroscopic posterosuperior rotator cuff tear TOE repair was performed alone (Control group) or with BCI applied over the TOE repair (BCI group). The primary outcome was the retear rate (defined as Sugaya 4-5) determined by MRI at 12 months of follow-up. Secondary outcomes were characteristics of the tendon (Sugaya grade and thickness of the healed tendon) and clinical outcomes (pain levels, EQ-5D-5L, American Shoulder and Elbow Surgeons, and Constant-Murley scores) at 12 months of follow-up. RESULTS: Of the 124 randomized patients, 122 (60 in the BCI group and 62 in the Control group) were available for MRI evaluation 12.2 ± 1.02 months after the intervention. There were no relevant differences in preoperative characteristics. Adding the BCI reduced the retear rate (8.3% [5/60] in the BCI group vs 25.8% [16/62] in the Control group, P = .010; relative risk of retear of 0.32 [95% confidence interval 0.13-0.83]). Sugaya grade was also better in the BCI group (P = .030). There were no differences between groups in the percentage of subjects who reached the MCID for CMS (76.7% vs 81.7%, P = .654) or American Shoulder and Elbow Surgeons (75% vs 80%, P = .829), in other clinical outcomes or in complication rates at 12.4 ± 0.73 (range 11.5-17) months of follow-up. CONCLUSIONS: Augmentation with a BCI of a TOE repair in a medium-to-large posterosuperior rotator cuff tear reduces the retear rate at 12-month follow-up by two-thirds, yielding similar improvements in clinical outcomes and without increased complication rates. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Cyst formation and bony ingrowth inside coil-type open-architecture anchors used for arthroscopic remplissage: a volumetric computed tomographic study of 50 anchors.

BACKGROUND: The use of anchors in the proximal humerus during arthroscopic surgery can cause localized bone loss due to osteolysis and cyst formation. The purpose of this study was to use computed tomography (CT) to evaluate the incidence of implant-related bone loss and cyst formation after implantation of polyetheretherketone (PEEK) coil-type open-architecture anchors during remplissage for the management of Hill-Sachs defects (HSDs) in patients with shoulder instability. METHODS: This was a single-cohort, observational study with a minimum of 12 months of follow-up. Subjects undergoing arthroscopic instability surgery with HSD requiring remplissage were included. The volume of the bone defects and the degree of bony ingrowth into the anchor were measured on CT images. RESULTS: Thirty-one participants (28 males, 3 females; mean age 29.4 years, standard deviation [SD] 10.6) in whom 50 anchors (4.5-mm Healicoil PEEK double-loaded anchors) were used were evaluated with a CT performed at a mean of 14.1 (SD 3.74) months after surgery. Full bony ingrowth inside the anchor was found in 15 anchors (30%, range 17.8%-44.5%); clear ossification with a thin lucent rim was found in 10 anchors (20%, range 10.0%-33.7%); discontinuous ossification was found in 8 anchors (16%, range 7.2%-29.1%); and no ossification was observed inside 17 anchors (34%, range 21.2%-48.7%). Regarding bone defect size, no bone defect was identified in 15 anchors (30%, 95% CI 17.9%-44.6%), a partial bone defect was found in 17 anchors (34%, 95% CI 21.2%-48.7%), hole enlargement was found in 17 anchors (34%, 95% CI 21.2%-48.7%), and 1 anchor caused a cyst larger than twice the size of the hole made for anchor insertion (2%, 95% CI 0.1%-8.6%). At the 1-year evaluation, none of the participants presented recurrence or residual apprehension. CONCLUSION: The use of PEEK coil-type open-architecture anchors for remplissage during instability surgery caused large cystic lesions in less than 10% of anchors. There was full bony ingrowth in one-third of anchors, and partial cancellous bone ingrowth occurred in another third of anchors.

Assessment of isolated glenohumeral range of motion in patients with adhesive capsulitis can help predict failure of conservative treatment: a pilot study.

PURPOSE: To prospectively evaluate a cohort of patients with adhesive capsulitis and identify predictors of failure of conservative treatment in the first 2 months of therapy. METHODS: This was a single-cohort, prospective observational study that included 20 participants (13 females/7 males; median age of 51.8 years [interquartile range: 8.65]) with primary adhesive capsulitis managed conservatively and evaluated clinically every month for at least 2 years of follow-up (29 [5] months). The evaluation included stage of the disease, treatment applied, radiological findings, pain levels and range of motion (active and passive ROM in the four planes and isolated glenohumeral passive ROM in abduction [GH-ABD], external rotation [GH-ER] and internal rotation). The main outcome assessed was failure of conservative treatment defined as the need for surgery and persistent pain or CMS below 70 points at the 1-year follow-up. RESULTS: Seven patients (7/20, 35%) were considered to have failed conservative treatment because they required arthroscopic capsular release 5.2 (2.1) months after the initial diagnosis. Of all the clinical and epidemiological variables, absence of improvement during the first 2 months in isolated glenohumeral ROM abduction and external rotation predicted failure of conservative treatment: improvement in GH-ABD (10° or more) occurred in 10/13 patients in the conservative treatment group and in 1/7 patients in the surgery group (p = 0.017). Improvement in GH-ER (10° or more) occurred in 9/13 patients in the conservative treatment group and in 0/7 patients in the surgery group (p = 0.005). CONCLUSIONS: Precise assessment of isolated glenohumeral ROM in patients with adhesive capsulitis can help identify patients in which conservative treatment might fail. In this study, patients who did not experience early improvements in isolated glenohumeral ROM often required surgery. LEVEL OF EVIDENCE: III (Prospective cohort study).

The prevalence of intraarticular associated lesions after acute acromioclavicular joint injuries is 20%. A systematic review and meta-analysis.

PURPOSE: To synthesise the evidence on the prevalence of associated intraarticular lesions in subjects with acute acromioclavicular joint (ACJ) dislocations. METHODS: A search in two electronic databases (PUMBMED and EMBASE) was performed from 1985 to 2019. Two independent reviewers selected studies that complied with the following inclusion criteria: (1) the study included data on surgically treated ACJ dislocation grade III-V in the Rockwood classification, (2) the ACJ injuries were acute (the surgery was performed less than 6 weeks after injury), (3) an arthroscopic evaluation of the glenohumeral joint was performed during surgery. The quality of the studies included was assessed using the tool of the Joanna Briggs Institute. RESULTS: A total of 47 studies with acute ACJ injuries met the initial inclusion criteria. Of these, 21 studies (9 retrospective case series, 9 prospective case series and 3 retrospective cohort studies) presented data on associated intraarticular lesions amenable for use in the meta-analysis. The meta-analysed studies included a total of 860 subjects with acute ACJ dislocations with a male/female ratio of 6.5 and a mean age of 32 years. The meta-analysis showed a prevalence of associated intraarticular lesions in subjects with acute ACJ of 19.9% (95% confidence interval [CI] 14.0-26.4%; 21 studies, 860 analysed participants; P = 0.000; I2: 74.5% random-effects model; low risk of bias). CONCLUSION: One in five subjects with surgically treated acute ACJ dislocations will have an associated intraarticular lesion that requires further intervention. The case for a customary arthroscopic evaluation of the joint, even when an open procedure is performed to deal with the ACJ dislocation, is strong. Level of evidence IV Trial registry Systematic review registration number: PROSPERO CRD42018090609.

Arthroscopic remplissage with all-suture anchors causes cystic lesions in the humerus: a volumetric CT study of 55 anchors.

PURPOSE: To evaluate with computed tomography (CT) the incidence of implant-related osteolysis after implantation of two types of all-suture anchors during remplissage for the management of Hill-Sachs lesions in shoulder instability. METHODS: Single-cohort, observational study with a minimum of 12 months follow-up. Twenty-five participants (19 males and 6 females; mean age 37.4 years [SD: 11.6]) with Hill-Sachs lesions requiring remplissage were evaluated with a CT performed a mean of 14.1 [3.74] months after surgery. Fifty-five all-suture anchors (19 2.3 mm Iconix and 36 1.7 mm Suturefix) were used. The volume of the bone defects was measured in the CT. Every anchor was classified into one of four groups: (1) no bone defect. (2) Partial bone defect (bone defects smaller than the drill used for anchor placement). (3) Tunnel enlargement (bone defect larger than the drill volume but smaller than twice that volume). (4) Cystic lesion (bone defect larger twice the drill volume). RESULTS: No bone defect was identified in only two anchors (3.6%, 95% CI 0.4-12.5%). A partial bone defect was found in eight anchors (14.5%, 95% CI 6.5-26.7%). In 35 anchors (63.6%, 95% CI 49.6-76.2%), there was enlargement of the bone defect that was smaller than 200% the size of the drill used. Ten anchors caused bone defects larger than twice the size of the drill used (18.2%, 95% CI 9.1-30.9%). The defect size was a mean of 89 mm3 (SD: 49 mm3, minimum 0 mm3, maximum 230 mm3). CONCLUSION: When using all-suture anchors in arthroscopic remplissage during instability surgery, relevant bone osteolytic defects are common at 1-year-follow-up. Cystic defects larger than twice the volume of the resected bone during implantation develop in one in six anchors and significant tunnel widening will develop in another three out of five anchors. This bone loss effectively increases the size and depth of the Hill-Sachs lesions but does not seem to affect short-term clinical outcomes. LEVEL OF EVIDENCE: Level IV.

Arthroscopic Bankart repair with all-suture anchors does not cause important glenoid bone osteolysis: a volumetric CT study of 143 anchors.

PURPOSE: To evaluate with computed tomography (CT) the incidence of anchor-related osteolysis after implantation of two types of all-suture anchors for the management of labral lesions in shoulder instability. METHODS: Single-cohort, observational study with 12-month follow-up. Thirty-three participants (27 males/6 females; age 38.3 years [SD 11.3]) with anterior labral lesions in which 143 all-suture anchors (71 Iconix 1.4 mm and 72 Suturefix 1.7 mm) were implanted were evaluated with a CT performed a mean of 15.4 [3.85] months after surgery. The volume of the bone defects was measured in the CT. Every anchor was classified into one of four groups: (1) no bone defect. (2) Partial bone defect (defects smaller than the drill used for anchor placement). (3) Tunnel enlargement (defects larger than the drill volume but smaller than twice that volume). (4) Cystic lesion (defects larger than twice the drill volume). RESULTS: No bone defect was identified in 16 anchors (11.2%, [95% CI 6.5-17.5%]). A partial bone defect was found in 84 anchors (58.7% [50.2-66.9%]). Tunnel enlargement was found in 43 anchors (30.11% [22.6-37.6%]). No anchor caused cystic lesions (0% [0-2.5%]). The defect volume was a mean of 27.8 mm3 (SD 18.4 mm3, minimum 0 mm3, maximum 94 mm3). Neither the position in the glenoid nor the type of implant used had a significant effect in the type or size of the defects. CONCLUSION: When using all-suture anchors in the glenoid during instability surgery, relevant bone osteolytic defects are rare at 1-year follow-up. Most anchor insertion tunnels will fill completely (11%) or partially (59%) with bone. Tunnel enlargement will develop in 30% of anchors. No cystic defects larger than 0.125 cm3 were observed. There is a low risk that all-suture anchors cause significant osteolytic bone defects in the glenoid. These implants can be used safely. Level of evidence IV.

Instability severity index score values below 7 do not predict recurrence after arthroscopic Bankart repair.

PURPOSE: To evaluate the efficacy of the Instability Severity Index Score (ISIS) in predicting an increased recurrence risk after an arthroscopic Bankart repair. METHODS: Retrospective review of a cohort of patients operated in three different centres. The inclusion criteria (recurrent anterior instability [dislocation or subluxation] with or without hyperlaxity, arthroscopic Bankart repair) and the exclusion criteria (concomitant rotator cuff lesion, acute first-time dislocation, surgery after a previous anterior stabilization, surgery for an unstable shoulder without true dislocation or subluxation; multidirectional instability) were those used in the study that defined the ISIS score. The medical records and a telephone interview were used to identify the six variables that define the ISIS and identify recurrences. RESULTS: One hundred and sixty-three shoulders met the inclusion and exclusion criteria. Of these, 140 subjects (22 females/118 males; mean age 35.5 ± 7.9) with 142 (89.0%) shoulders were available for follow-up after 5.3 (1.1) (range 3.1-7.4) years. There were 20 recurrences (14.1%). The mean (SD) preoperative ISIS was 1.8 (1.6) in the patients without recurrence and 1.8 (1.9) in the patients with recurrence (n.s.). In the 117 subjects with ISIS between 0 and 3 the recurrence rate was 12.8%; in the 25 with ISIS 4 to 6 the rate was 20% (n.s.). CONCLUSION: For subjects with anterior shoulder instability in which an arthroscopic Bankart repair is being considered, the use of the ISIS, when the values obtained are ≤ 6 was not useful to predict an increased recurrence risk in the midterm in this retrospectively evaluated case series. The efficacy of the ISIS score in defining a group of subjects with a preoperative increased risk of recurrence after an arthroscopic Bankart instability repair is limited in lower risk populations (with ISIS scores ≤ 6). LEVEL OF EVIDENCE: Retrospective case series, Level IV.

The absorbable subacromial spacer for irreparable posterosuperior cuff tears has inconsistent results.

PURPOSE: To evaluate the 2-year results of an absorbable subacromial spacer in patients with irreparable posterosuperior rotator cuff tears. METHODS: Prospective longitudinal study of a consecutive case series of 16 subjects with irreparable tears of the posterosuperior rotator cuff in which the InSpace® subacromial spacer was arthroscopically implanted. A full clinical evaluation that included the Constant test, Simple Shoulder Test (SST) and the QuickDash questionnaire was performed preoperatively and at 12 and 24 months follow-up. The primary outcome for assessing the success of the procedure was a variable composed of a clinically relevant variation of the Constant (established in an improvement greater than 10 points) and the absence of surgical reintervention. RESULTS: Fifteen subjects (11 women/4 men, median age = 69.4 years [interquartile range 7.50], range 60-80 years) completed the 2-year of follow-up. According to the main evaluation criteria, only 6 patients (40%) had a successful outcome. Five subjects required reconversion to a reverse shoulder arthroplasty (at a median of 9.8 months postoperatively) due to absence of clinical improvement or worsening of symptoms. Of the ten remaining subjects, only 6 had improvements greater than 10 points in the Constant score. Despite of this, these 10 subjects had, on average, some improvement in the Constant test (preoperative Constant: median 35.0 [27.0-52.5] vs Constant at 24 months: 53.5 [55.0-84.0], significant differences p = 0.02), in the SST (3.0 [2.0-4.0] vs 6.0 [3.25-7.75], p = 0.039) and in the QuickDASH test (37.0 [33.25-40.0] vs 27.5 [20.5-32.75], p = 0.012). CONCLUSIONS: The outcomes of the implantation of the subacromial biodegradable spacer at 2-year follow-up are not satisfactory. In this small case series only 40% of patients seem to clearly benefit from surgery. One in three required revision to a reverse shoulder arthroplasty. The described technique does not seem a reasonable alternative for the management of the majority of patients with irreparable ruptures of the rotator cuff. The indications of this device should be more clearly defined. LEVEL OF EVIDENCE: IV.

Decadal changes in biomass and distribution of key fisheries species on Newfoundland's Grand Banks.

Canadian fisheries management has embraced the precautionary approach and the incorporation of ecosystem information into decision-making processes. Accurate estimation of fish stock biomass is crucial for ensuring sustainable exploitation of marine resources. Spatio-temporal models can provide improved indices of biomass as they capture spatial and temporal correlations in data and can account for environmental factors influencing biomass distributions. In this study, we developed a spatio-temporal generalized additive model (st-GAM) to investigate the relationships between bottom temperature, depth, and the biomass of three key fished species on The Grand Banks: snow crab (Chionoecetes opilio), yellowtail flounder (Limanda ferruginea), and Atlantic cod (Gadus morhua). Our findings revealed changes in the centre of gravity of Atlantic cod that could be related to a northern shift of the species within the Grand Banks or to a faster recovery of the 2J3KL stock. Atlantic cod also displayed hyperaggregation behaviour with the species showing a continuous distribution over the Grand Banks when biomass is high. These findings suggest a joint stock assessment between the 2J3KL and 3NO stocks would be advisable. However, barriers may need to be addressed to achieve collaboration between the two distinct regulatory bodies (i.e., DFO and NAFO) in charge of managing the stocks. Snow crab and yellowtail flounder centres of gravity have remained relatively constant over time. We also estimated novel indices of biomass, informed by environmental factors. Our study represents a step towards ecosystem-based fisheries management for the highly dynamic Grand Banks.

The size of the Hill Sachs defect increases during reduction of a first time shoulder dislocation in older adults: a pilot study in 20 cases.

PURPOSE: To evaluate if the size of Humeral Hill-Sachs Defects (HSDs) increases during reduction in the emergency department (ED) in subjects that have a first-time anterior shoulder dislocation. METHODS: Subjects more than 18 years old presenting to the ED a first-time anterior shoulder dislocation were included. A computed tomography was performed prior to any reduction attempt (Pre-CT). The shoulder was reduced in the emergency room with intraarticular lidocaine; if two attempts failed, the shoulder was reduced under anaesthesia. A second CT was performed after reduction of the shoulder (Post-CT). CT were evaluated using the Osirix software. A 3-dimensional reconstruction of the humeral head was performed and the maximum width of the humeral defect, maximum depth of the humeral defect and total volume of the humeral defect were measured. The relative increase in size was calculated. RESULTS: Twenty subjects were included in the study. All subjects presented HSDs in the Pre-CT that had a width of a median of 9.9(interquartile range:2.9)mm, a depth of 7.0(3.0]mm and a volume of 355(333)mm2. The HSD in the Post-CT had a width of 10.9(3.0)mm (an increase of 7.23[8.5]%, significant differences, p = 0.0001) a depth of 7.2(2.7)mm (an increase of 9.93[20.7]%, significant differences, p < 0.0001) and a volume of 469(271) mm2 (an increase of 27.5[26.9]%, significant differences, p < 0.0001). There were size increases larger than 25% in 15/20 (75%) of subjects. CONCLUSION: Standard reduction manoeuvres performed in a first-time anterior shoulder dislocation increase the size of the HSD. This increase in size is larger than 25% in four out of five cases. LEVEL OF EVIDENCE: IV, prospective cases series study.

Anatomic acromioclavicular and Coracoclavicular ligament reconstruction with allograft is effective for the management of non-acute acromioclavicular dislocations.

OBJECTIVE: to analyze the short-term outcomes of an anatomical technique that reconstructs both the acromioclavicular and coracoclavicular ligaments with the help of a tendon allograft for the management of non-acute acromioclavicular dislocations. METHODS: this is a prospective longitudinal study of a case series of subjects with symptomatic non-acute (>3 weeks) acromioclavicular dislocations surgically managed with an anatomical reconstruction of both the acromioclavicular and coracoclavicular ligaments using tibial tendon allografts. Outcomes were assessed with simple standardized radiographs and with the Constant-Murley, American Shoulder and Elbow Surgeons (ASES)-shoulder and Quick-DASH (Disabilities of the Arm, Shoulder and Hand) scales; also, the acromioclavicular joint stability and the scapulothoracic kinematics were assessed. RESULTS: a total of 19 subjects were assessed. There were no intraoperative or early postoperative complications. After a minimum two year follow-up (mean 3.12 years, [standard deviation 1.10 years]), there were significant improvements in all three of the scales: The Constant-Murley score increased from 65.4 (13.0) preoperatively to 92.6 (11.2) at the end of follow-up (p<0.001); the Quick-DASH score improved from 21.3 (6.73) to 13.0(4.58) (p<0.001); and the ASES-shoulder score increased from 56.6 (14.6) to 91.0 (9.86) (p<0.001). The AC joint was stable in both the vertical and the horizontal plane, without residual scapulothoracic dysfunction in 18/19 subjects at the end of follow-up. Only one patient presented a poor functional outcome, with loss of reduction, instability and persistent symptoms. Another subject suffered loss of reduction, though without functional repercussions. Two subjects had asymptomatic distal clavicle osteolysis and two developed radiographic osteoarthritis and were also asymptomatic. Moderate widening of the tunnels was observed in most patients: tunnel size after surgery was 5.1 (0.3) mm versus 5.8 (1.1) mm at the end of follow-up (p = 0.001) but widening was not correlated to final function. CONCLUSIONS: the anatomical reconstruction of the acromioclavicular and coracoclavicular ligament complexes with a tendon allograft yields excellent clinical outcomes when used in subjects with symptomatic non-acute acromioclavicular dislocations. Secondary tunnel widening, distal clavicle osteolysis and osteoarthritis might be of concern but do not affect clinical outcomes.

Evaluation of the inter and intraobserver reproducibility of the GRASP method: a goniometric method to measure the isolated glenohumeral range of motion in the shoulder joint.

PURPOSE: To evaluate the intra and interobserver reproducibility of a new goniometric method for evaluating the isolated passive range of motion of the glenohumeral joint in an outpatient setting. METHODS: This is a prospective observational study on healthy subjects. The Glenohumeral ROM Assessment with Scapular Pinch (GRASP) method is a new method for assessing the isolated range of motion (ROM) of the glenohumeral joint (GH) by a single examiner with a clinical goniometer. It measures the isolated glenohumeral passive abduction (GH-AB), passive external rotation (GH-ER) and internal rotation (GH-IR) with the arm at 45º of abduction. These three GH ROM parameters were measured in both shoulders of 30 healthy volunteers (15 males/15 females, mean age:41.6[SD = 10.3] years). The full shoulder passive abduction, passive external rotation and internal rotation 45º of abduction were measured by the same examiners with a goniometer for comparison. One examiner made two evaluations and a second examiner made a third one. The primary outcome was the intra- and interobserver reproducibility of the measurements assessed with intraclass correlation coefficients (ICC) and the Bland-Altman plot. RESULTS: The intra-observer ICC for isolated glenohumeral ROM were: 0.84 ± 0.07 for GH-ABD, 0.63 ± 0.09 for GH-ER, and 0.61 ± 0.14 for GH-IR. The inter-observer ICC for isolated glenohumeral ROM were: 0.86 ± 0.06 for GH-ABD, 0.68 ± 0.12 for GH-ER, and 0.62 ± 0.14 for GH-IR. These results were similar to those obtained for full shoulder ROM assessment with a goniometer. CONCLUSION: The GRASP method is reproducible for quick assessment of isolated glenohumeral ROM. LEVEL OF EVIDENCE: III.

Management of Humeral Defects in Anterior Shoulder Instability.

BACKGROUND: A Hill Sachs lesion is a posterior-superior bony defect of the humeral head caused by a compression of the hard glenoid rim against the soft cancellous bone in the context of an anterior instability episode. The presence of these humeral defects increases with the number of dislocations and larger lesions are associated with a greater chance of development of recurrent instability and recurrence after surgery. Also its location and pattern, in particular the so-called engaging Hill-Sachs, are associated with poor prognosis. METHODS: There is a lack of consensus in terms of classification and management algorithm, although lesions greater than 25% of the humeral head had been suggested to need more than a simple Bankart repair to avoid recurrence. The concept of glenoid track has turned the attention to location and shape and not only size of the humeral defect. Moreover, the glenoid bone loss is crucial when choosing a treatment option as it contributes to decrease the glenoid track as well. A thorough revision of treatment options has been performed. RESULTS: Numerous treatment options have been proposed including remplissage, glenoid or humeral head augmentation, bone desimpaction, humeral rotational osteotomy and arthroplasty. CONCLUSION: Humeral defects treatment should be individualized. Determination of size and location of the defect and its relation with glenoid track is mandatory to achieve satisfactory results.

The Posterior Unstable Shoulder: Natural History, Clinical Evaluation and Imaging.

BACKGROUND: There is a low incidence of posterior instability which is present in only 2% to 10% of all unstable shoulders. The posterior instable shoulder includes different manifestations like fixed dislocation, recurrent subluxation or dislocation. METHODS: Research and online content related to posterior instability is reviewed. Natural history, clinical evaluation and imaging are described. RESULTS: An awareness of the disorder, together with a thoughtful evaluation, beginning with the clinical history, usually leads to proper diagnosis. An appropriate physical exam, taking in account hyperlaxity and specific tests for posterior instability should be done. CONCLUSION: Posterior shoulder instability is an uncommon condition and is challenging to diagnose. There is not a single injury that is responsible for all cases of recurrent shoulder dislocation or subluxation, and the presence of soft tissue lesions or bone alterations should be evaluated, with the use of adequate simple radiology and multiplanar imaging.