Hill-Sachs and reverse Hill-Sachs lesions come in different shapes and sizes, and their effect on “glenoid track” can vary. Small Hill-Sachs lesions that do not engage can be successfully treated with a Bankart repair alone done arthroscopically or open. Moderate, engaging, Hill-Sachs lesions can be treated either with the addition of remplissage to an arthroscopic Bankart or by adding the triple blocking effect of the Bristow-Latarjet procedure. Surface replacements vary in size from the small hemi-cap type of procedure to an entire humeral head replacement (HHR). These devices can be used as opposed to allograft replacement when the risk of post-reconstruction arthritis is high with the aforementioned more conventional treatment techniques. When 45% or more of the humeral head is involved with the lesion, or Outerbridge stage III and IV changes prevail, a HHR is preferred. An oval shaped HHR is the author's preference, and the long diameter can be used to provide coverage anteriorly or posteriorly and is particularly useful in large Hill-Sachs lesions associated with epilepsy

The Hill-Sachs lesion is a bony defect of the humeral head that occurs in association with anterior instability of the glenohumeral joint. Hill-Sachs lesions are common, with an incidence approaching nearly 100% in the setting of recurrent anterior glenohumeral instability. However, the indications for surgical management are very limited, with less than 10% of anterior instability patients considered for treatment of the Hill-Sachs lesion. Of utmost importance is addressing bone loss on the anterior-inferior glenoid, which is highly successful at preventing recurrence of instability even with humeral bone loss. In the rare situation where the Hill-Sachs lesion may continue to engage the glenoid, surgical management is indicated. Surgical strategies are variable, including debridement, arthroscopic remplissage, allograft transplantation, surface replacement, and arthroplasty. Given that the population with these defects is typically comprised of young and athletic patients, biologic solutions are most likely to be associated with decades of sustainable joint preservation, function, and stability. The first priority is maximizing the treatment of anterior instability on the glenoid side. Then, small lesions of less than 10% are ignored without consequence. Lesions involving 10–20% of the humeral head are treated with arthroscopic remplissage (defect filled with repair of capsule and infraspinatus). Lesions greater than 20% that extend beyond the glenoid tract are managed with fresh osteochondral allografts to biologically restore the humeral head. Lesions great than 40% are most commonly associated with advanced arthritis and deformity of the humeral articular surface and are therefore treated with a humeral head replacement. This treatment algorithm maximises our ability to stabilise and preserve the glenohumeral joint

Bone defects are frequently observed in anterior shoulder instability. Over the last decade, knowledge of the association of bone loss with increased failure rates of soft-tissue repair has shifted the surgical management of chronic shoulder instability. On the glenoid side, there is no controversy about the critical glenoid bone loss being 20%. However, poor outcomes have been described even with a subcritical glenoid bone defect as low as 13.5%. On the humeral side, the Hill-Sachs lesion should be evaluated concomitantly with the glenoid defect as the two sides of the same bipolar lesion which interact in the instability process, as described by the glenoid track concept. We advocate adding remplissage to every Bankart repair in patients with a Hill-Sachs lesion, regardless of the glenoid bone loss. When critical or subcritical glenoid bone loss occurs in active patients (> 15%) or bipolar off-track lesions, we should consider anterior glenoid bone reconstructions. The techniques have evolved significantly over the last two decades, moving from open procedures to arthroscopic, and from screw fixation to metal-free fixation. The new arthroscopic techniques of glenoid bone reconstruction procedures allow precise positioning of the graft, identification, and treatment of concomitant injuries with low morbidity and faster recovery. Given the problems associated with bone resorption and metal hardware protrusion, the new metal-free techniques for Latarjet or free bone block procedures seem a good solution to avoid these complications, although no long-term data are yet available. Cite this article: Bone Joint J 2024;106-B(10):1100–1110

Introduction: Locked posterior dislocations of the shoulder, with humeral head defects are rare injuries. It constitutes less than 2% of all posterior dislocations of the shoulder and 60% are misdiagnosed. There have only been a few articles describing the treatment of such injuries either by bone graft or Mc Laughlin’s procedure.

Patients: The first patient is a 23 year-old who presented as a missed diagnosis three weeks after a seizure. The second is a 35 year-old male referred four weeks after a traumatic dislocation. The third is a 55 year-old, known epileptic, who was diagnosed on admission. CT scan revealed a locked humeral head against the posterior glenoid rim, with defects of 30%, 20% and 30% respectively.

Treatment: All underwent reconstruction of the defect. The first using freeze-dried allograft, the second and third using iliac autograft.

Results: Each patient was assessed using the Constant and Murley score. The first patient scored 76 points at 30 months, the second patient scored 95 at 12 months and the third scored 97 after 12 months post-operatively.

Conclusion: Early diagnosis is important in management and prognosis of such injuries. Using bone graft in the reconstruction of the humeral head defect restores the normal anatomy, rather than distorting it by using McLaughlin’s procedure.

Aims

Glenoid bone loss is a significant problem in the management of shoulder instability. The threshold at which the bone loss is considered “critical” requiring bony reconstruction has steadily dropped and is now approximately 15%. This necessitates accurate measurement in order that the correct operation is performed. CT scanning is the most commonly used modality and there are a number of techniques described to measure the bone loss however few have been validated. The aim of this study was to assess the accuracy of the most commonly used techniques for measuring glenoid bone loss on CT.

Anterior shoulder instability is associated with osseous defects of the glenoid and/or humeral head (Hill-Sachs lesions). These defects can contribute to the pathology of instability by engaging together. There is a need to continue to develop methods to preoperatively identify engaging Hill-Sachs lesions for determining appropriate surgical management. The objective was to created a working moveable 3D CT model that allows the user to move the shoulder joint into various positions to assess the relationship between the Hill-Sachs lesion and the anterior glenoid rim. This technique was applied to a cohort series of 14 patients with recurrent anterior dislocation: 4 patients had undergone osteoarticular allografting of Hill-Sachs lesions and 10 control patients had undergone CT scanning to quantify bone loss but had no treatment to address bony pathology. A biomechanical analysis was performed to rotate each 3D model using local coordinate systems through a functional range using an open-source 3D animation program, Blender (Amsterdam, Netherlands). A Hill-Sachs lesion was considered “dynamically” engaging if the angle between the lesion's long axis and anterior glenoid was parallel. In the classical vulnerable position of the shoulder (abduction=90, external rotation=0–135), none of the Hill-Sachs lesions aligned with the anterior glenoid in any of our patients (Figure 1). Therefore, we considered there to be a “low risk” of engagement in these critical positions, as the non-parallel orientation represents a lack of true articular arc mismatch and is unlikely to produce joint instability. We then expanded our search and simulated shoulder positions throughout a physiological range of motion for all groups and found that 100% of the allograft patients and 70% of the controls had positions producing alignment and were “high risk” of engagement (p = 0.18) (Table 1). We also found that the allograft group had a greater number of positions that would engage (mean 4 ± 1 positions of engagement) compared to our controls (mean 2 ± 2 positions of engagement, p = 0.06). We developed a 3D animated paradigm to dynamically and non-invasively visualize a patient's anatomy and determine the clinical significance of a Hill-Sachs lesion using open source software and CT images. The technique demonstrated in this series of patients showed multiple shoulder positions that align the Hill-Sachs and glenoid axes that do not necessarily meet the traditional definition of engagement. Identifying all shoulder positions at risk of “engaging”, in a broader physiological range, may have critical implications towards selecting the appropriate surgical management of bony defects. We do not claim to doubt the classic conceptual definition of engagement, but we merely introduce a technique that accounts for the dynamic component of shoulder motion, and in doing so, avoid limitations of a static criteria assumed traditional definition (like size and location of lesion). Further investigations are planned and will help to further validate the clinical utility of this method. For any figures or tables, please contact the authors directly

Background:. Individuals with large Hill-Sachs lesions may be prone to failure and reoccurrence following standard arthroscopic Bankart repair. Here, the Remplissage procedure may promote shoulder stability through infraspinatus capsulo-tenodesis directly into the lesion. Little biomechanicaldata about the Remplissage procedure on glenohumeral kinematics, stability, and range of motion (ROM) currently exists. Questions/purposes:. What are the biomechanical effects of Bankart and Remplissage repair for large Hill-Sachs lesions?. Methods:. Six cadaveric shoulders were tested using a custom shoulder testing system. ROM and glenohumeral translation with applied loads in anterior-posterior (AP) and superior-inferior (SI) directions were quantified at 0° and 60° gleno-humeral abduction. Six conditions were tested: intact, Bankart lesion, Bankart with 40% Hill-Sachs lesion, Bankart repair, Bankart repair with Remplissage, and Remplissage repair alone. Results:. Humeral external rotation (ER) and total range of motion (TR) increased significantly from intact after the creation of the Bankart lesion at both 0° abduction (ER +27.0°, TR +35.8°, p < 0.05) [Fig 1] and 60° abduction (ER +9.5°, TR +30.7°, p < 0.05) [Fig 2], but did not increase further with the addition of the Hill-Sachs lesion. The Bankart repair restored range of motion to intact values 0° abduction at addition of the Remplissage repair did not significantly alter range of motion from the Bankart repair alone. There were no significant changes in AP or SI translation between Bankart repair with and without Remplissage compared to the intact specimen. Conclusions:. The addition of the Remplissage procedure for treatment of large Hill-Sachs lesions had no statistically significant effect on ROM or translation for treatment for large Hill-Sachs lesions. Clinical Relevance: The Remplissage technique may be a suitable option for engaging Hill-Sachs lesions. Further clinical studies are warranted

First-time anterior dislocation of the shoulder is associated with the development of recurrent instability. It is recognised that patients with recurrent instability often have osseous defects. Using 3D computerised tomography (3DCT) it is possible to quantify these defects. Whether these defects are present after the primary dislocation or occur progressively from multiple dislocations is unclear. We correlated the presence of Hill-Sachs lesions and anterior glenoid bone loss with evidence of recurrent dislocation and clinical outcomes. 78 patients were followed up for two years. All underwent a 3DCT within a week of injury. Standardised images of the humeral head and glenoid were produced. Using standardised digital techniques bone loss was measured. 39% of the patients developed further instability. Average Hill-Sachs circumferential length = 15.23%. Average Hill-Sachs surface area = 5.53%. The length and surface area of the Hill-Sachs lesions were significantly associated with further instability. (p=0.019 and p=0.003). Average en face glenoid surface area loss=1.30% with no association to instability (p=0.685). There was poor correlation between the size of the glenoid lesion and the size of the Hill-Sachs lesion. Results showed that age and increasing size of the Hill-Sachs lesions result in a higher rate of instability. Interestingly glenoid bone loss was relatively low and did not predict recurrent instability. The size of the Hill-Sachs lesion does not have a linear relationship with glenoid bone loss. Further work defining the morphology of the Hill-Sachs lesion and its engagement with a glenoid defect is required

The classic Hill-Sachs lesion is a compression or impression fracture of the humeral head in occurrence with anterior glenohumeral instability. The true incidence is unknown but clearly increases with recurrent instability episodes. Recent peer-reviewed literature has highlighted the importance of addressing “significant” humeral and glenoid bone defects in the management of glenohumeral instability. Quantification of the “significance” of a Hill-Sachs lesion with regard to location, size, and depth in relation to the glenoid has helped guide indications for surgical management. Options for managing Hill-Sachs lesions include both humeral-sided techniques (soft tissue, bone, and/or prosthetic techniques) and also glenoid-sided techniques (bone transfers to increase glenoid width). The majority of significant acute or chronic Hill-Sachs lesions can be effectively managed without prosthetic replacement. Is a prosthetic surface replacement ever indicated for the management of Hill-Sachs lesions? The peer-reviewed literature is sparse with the outcomes of this treatment, and significant consideration must be given to both the age of the patient and the need for such management when other effective non-prosthetic options exist. In a patient with more than half of the humeral head involved after instability episodes (perhaps seizure or polytrauma patients), metallic surface replacement arthroplasty may be an option that could require less involved post-operative care while restoring range of motion and stability

Purpose. The presence of a Hill-Sachs lesion is a major contributor to failure of surgical intervention following anterior shoulder dislocation. The relationship between lesion size, measured on pre-operative MRI, and risk of recurrent instability after surgery has not previously been defined. Hypothesis: We hypothesized that the size of Hill-Sachs lesions on pre-op MRI would be greater among patients who failed soft tissue stabilization when compared to patients who did not fail. We also hypothesized that the existence of a glenoid lesion would lead to failure with smaller Hill-Sachs lesions. Method. Nested case-control analysis of 114 patients was performed to evaluate incidence of failure after soft tissue stabilization. Successful follow-up of at least 24 months was made with 91 patients (80%). Patients with recurrent instability after surgery were compared to randomly selected age and sex matched controls in a 1:1 ratio. Pre-operative sagittal and axial MRI series were analyzed for presence of Hill-Sachs lesions, and maximum edge-to-edge length and depth as well as location of the lesion related to the bicipital groove (axial) and humeral shaft (sagittal) were measured. Results. Of 91 patients included in analysis, 77 (84.6%) had identifiable Hill-Sachs lesions. 32 patients (35.2%) suffered from failure of soft tissue stabilization (redislocation 22.0%; subjective instability 13.2%). Ten of these patients (11.0%) underwent further surgery. When comparing the age and sex matched failure and control groups, statistically significant differences in unadjusted data were found for axial edge-to-edge length (p = 0.01), axial depth (p = 0.01), and sagittal edge-to-edge length (p = 0.04), with larger sized lesions found in the failure group (Figure 1). Differences trended towards significant for sagittal depth and angle from the bicipital groove. Conclusion. In this retrospective case-control study, humeral head defect size was positively correlated with recurrent instability after soft-tissue stabilization. Larger Hill-Sachs lesions, as measured on pre-op MRI, were found in patients who failure surgical intervention when compared to patients who did not fail. These data and future studies may help determine pre-operative clinical guidelines for the treatment of anterior shoulder dislocation

The aim of this study was to determine if the extent of the glenoid and humeral bone loss affects the rate of recurrent instability and the functional outcome following the Latarjet procedure. 161 patients underwent open Latarjet procedure during the period 2006–2015 (Mean age 30.0 years, 150t (93.2%) Male, 118 (73.3%) primary procedure). Functional outcome was measured using the Western Ontario Shoulder Instability Index (WOSI) and Quick Disabilities of the Arm, Shoulder and Hand (QuickDash) score at a mean of 4.7 years post-operatively. All patients underwent computed tomographic (CT) imaging pre-operatively. Using three-dimensional reconstruction, the glenoid bone loss, Hill-Sachs lesion and ‘Glenoid Track’ status was recorded. Radiographically-confirmed redislocation was rare (1.2%), but 18.5% (n=23/124) reported ongoing subjective shoulder instability. Fifty-two shoulders (32.3%) were classified as “Off-Track”. The median Quick DASH and WOSI scores were 2.27 (IQR 9.09; range 0–70.45) and 272.0 (IQR 546.5; range 0–2003), respectively. There were no significant differences observed between overall Quick DASH scores or WOSI scores for either On-Track or Off-Track groups (p=0.7 and 0.73, respectively). Subjective instability was not influenced by the degree of glenoid bone loss (p=0.82), the overall size of the Hill-Sachs lesion (p=0.80), or the presence of an ‘Off-Track’ lesion (p=0.84). Functional outcome and recurrent instability following the Latarjet procedure do not appear to be influenced by the extent of glenohumeral bone loss prior to surgery

Purpose: The Instability Severity Index Score (ISIS) is a 6-item questionnaire that has been reported to predict failure of arthroscopic Bankart repair among patients treated for recurrent anterior glenohumeral instability. Two of the ISIS items pertain to radiographic features (presence of a Hill-Sachs lesion, loss of glenoid contour). These, however have yet to be validated. The goal of this study was to examine the inter – and intra-rater agreement and corresponding reliability of the radiographic aspects of the ISIS. Method: Fifty-two plain, randomly selected, true antero-posterior radiographs in 45° gleno-humeral external rotation were evaluated by five assessors (three upper extremity orthopaedic surgeons, one senior orthopaedic resident and one musculoskeletal radiologist). Radiographs were retrieved for patients with documented recurrent shoulder instability requiring surgical stabilization and placed in a blinded Microsoft Powerpoint presentation for evaluation. Assessors were asked to determine the presence/absence of a Hill-Sachs lesion and if a loss of glenoid contour was present. Radiographs were evaluated in random order on two occasions, separated by a one-week time interval. Intra – and inter-rater reliability was assessed using percentage of agreement and kappa statistics. Results: For session one, the number of Hill-Sachs lesions observed among raters ranged from 11 to 32. This resulted in inter-rater agreement ranging from 48% to 78% (k = 0.07 to 0.42), indicating poor to fair reliability. Cases with loss of glenoid contour ranged from seven to 14 with inter-rater agreement of 66% and 90% (k = 0.01 to 0.61), suggesting poor to moderate reliability. Session two led to modest increases in inter-rater agreement. The number of Hill-Sachs lesions observed ranged from four to 30 (agreement of 48% to 84%; k = 0.11 to 0.60) indicating fair to moderate reliability and the number of cases with loss of glenoid contour ranged from three to 14 (agreement of 66% to 94%; k = – 0.04 to 0.69), ranging from poor to moderate reliability. With respect to intra-rater reliability, agreement ranged from 71% to 94% (k = 0.41 to 0.86) for Hill-Sachs lesions, indicating fair to good reliability and 76% to 94% (k= 0.20 to 0.74) for loss of glenoid contour, ranging from fair to good reliability. Intra-rater agreement and corresponding kappa values were highest among the upper extremity surgeons and the musculoskeletal radiologist, particularly for loss of glenoid contour (85% to 94%; k = 0.56 to 0.74) suggesting there is moderate to good reliability in this measurement. Conclusion: Our results indicate that the intra-rater reliability of the ISIS radiographic features was highest among upper extremity specialists and the musculoskeletal radiologist, suggesting that the ISIS may have utility in an experienced clinician’s individual practice. As the inter-rater reliability appears low, particularly for Hill-Sachs lesions, its wide-spread use across surgeons should be examined in further research

The Hill-Sachs lesion is a bony defect of the humeral head that occurs in association with anterior instability of the glenohumeral joint. Hill-Sachs lesions are common, with an incidence approaching nearly 100% in the setting of recurrent anterior glenohumeral instability. However, the indications for surgical management are very limited, with less than 10% of anterior instability patients considered for treatment of the Hill-Sachs lesion. Of utmost importance is addressing bone loss on the anterior-inferior glenoid, which is highly successful at preventing recurrence of instability even with humeral bone loss. In the rare situation where the Hill-Sachs lesion may continue to engage the glenoid, surgical management is indicated. Surgical strategies are variable, including debridement, arthroscopic remplissage, allograft transplantation, surface replacement, and arthroplasty. Given that the population with these defects is typically comprised of young and athletic patients, biologic solutions are most likely to be associated with decades of sustainable joint preservation, function, and stability. The first priority is maximising the treatment of anterior instability on the glenoid side. Then, small lesions of less than 10% are ignored without consequence. Lesions involving 10–20% of the humeral head are treated with arthroscopic remplissage (defect filled with repair of capsule and infraspinatus). Lesions greater than 20% that extend beyond the glenoid tract are managed with fresh osteochondral allografts to biologically restore the humeral head. Lesions great than 40% are most commonly associated with advanced arthritis and deformity of the humeral articular surface and are therefore treated with a humeral head replacement. This treatment algorithm maximises our ability to stabilise and preserve the glenohumeral joint

Previously, we conducted a multi-center, double-blinded randomized controlled trial comparing arthroscopic Bankart repair with and without remplissage. The end point for the randomized controlled trial was two years post-operative, providing support for the benefits of remplissage in the short term in reducing recurrent instability. The aim of this study was to compare the medium term (3 to 9 years) outcomes of patients previously randomized to have undergone isolated Bankart repair (NO REMP) or Bankart repair with remplissage (REMP) for the management of recurrent anterior glenohumeral instability. The rate of recurrent instability and instances of re-operation were examined. The original study was a double-blinded, randomized clinical trial with two 1:1 parallel groups with recruitment undertaken between 2011 and 2017. For this medium-term study, participants were reached for a telephone follow-up in 2020 and asked a series of standardized questions regarding ensuing instances of subluxation, dislocation or reoperation that had occurred on their shoulder for which they were randomized. Descriptive statistics were generated for all variables. “Failure” was defined as occurrence of a dislocation. “Recurrent instability” was defined as the participant reporting a dislocation or two or more occurences of subluxation greater than one year post-operative. All analyses were undertaken based on intention-to-treat whereby their data was analyzed based on the group to which they were originally allocated. One-hundred and eight participants were randomized of which 50 in the NO REMP group and 52 in the REMP group were included in the analyses in the original study. The mean number of months from surgery to final follow-up was 49.3 for the NO REMP group and 53.8 for the REMP group. The rates of re-dislocation or failure were 8% (4/52) in the REMP group at an average of 23.8 months post-operative versus 22% (11/50) in the NO REMP at an average of 16.5 months post-operative. The rates of recurrent instability were 10% (5/52) in the REMP group at an average of 24 months post-operative versus 30% (15/50) in the NO REMP group at an average of 19.5 months post-operative. Survival curves were significantly different favouring REMP in both scenarios. Arthroscopic Bankart repair combined with remplissage is an effective procedure in the treatment of patients with an engaging Hill-Sachs lesion and minimal glenoid bone loss (<15%). Patients can expect favourable rates of recurrent instability when compared with isolated Bankart repair at medium term follw-up

Purpose. The management of moderate to large engaging Hill-Sachs lesions is controversial and surgical options include remplissage, allograft reconstruction, and partial resurfacing arthroplasty. Few in-vitro studies have quantified their biomechanical characteristics and none have made direct comparisons. The purpose of this study was to compare joint stability and range of motion (ROM) among these procedures using an in-vitro shoulder simulator. It was hypothesized that all procedures would prevent defect engagement, but allograft and partial resurfacing would most accurately restore intact biomechanics; while remplissage would provide the greatest stabilization, possibly at the expense of motion. Method. Eight cadaveric shoulders were tested on an active in-vitro shoulder simulator. Each specimen underwent testing in 11 conditions: intact, Bankart lesion, Bankart repair, and two unrepaired Hill-Sachs lesions (30% & 45%) which were then treated with each of the three techniques. Anterior joint stability, ROM in extension and internal-external rotation, and glenohumeral engagement were assessed. Stability was quantified as resistance, in N/mm, to an anteriorly applied load of 70N. Results. Remplissage significantly increased joint stiffness compared to both defects (6.43.8 N/mm, p=0.01) and the allograft and partial resurfacing (p <= 0.04). No technique significantly surpassed the stability of the intact state (p>0.05). In adduction, the remplissage significantly reduced internal-external rotation compared to both defects (p <= 0.01), but only the 30% repair caused a significant change compared to the intact state (14.511.3 N/mm, p=0.05). In abduction, all repairs reduced rotation ROM compared to the Hill-Sachs defect (>= 8.24o, p <= 0.04), but none with respect to the intact condition (p >= 0.05). Remplissage had significantly less extension than either resurfacing procedure (>= 15.4o, p <= 0.02) and resulted in a greater reduction in extension ROM for 45% defects compared to 30% defects (11.918.91, p=0.06). All unrepaired lesions engaged during extension. None of the remplissage or allograft reconstructions engaged, however, 75% of partial resurfacing arthroplasties partially engaged. Conclusion. This study is the first biomechanical evaluation to directly compare three surgical procedures for engaging Hill-Sachs lesions. Each procedure enhanced stability; however, the enhancement provided by the resurfacing repairs more closely resembled the intact state. Remplissage of the 30% and the 45% defects improved stability and eliminated glenohumeral engagement but caused significant and progressive reductions in ROM. In comparison, both the allograft and partial resurfacing procedures re-established ranges of motion approaching those of the intact joint; however, the partial resurfacing could not fully prevent engagement. These findings indicate that the effects of each technique are not equivalent and further clinical and biomechanical studies are required

We describe the treatment of traumatic anterior shoulder instability complicated with Hill-Sachs lesion, using a combined arthroscopic technique of anterior & posterior capsular fixation and infraspinatus tenodesis by means of suture-anchors, in order to fill the humeral head bone defect (i.e. “remplissage”). We use 2 posterior portals introducing the arthro-scope through the upper one. A double-armed suture-anchor is inserted through each portal piercing the infranspinatous tendon & posterior capsule in an extra-articular mattress mode. The humeral head bone defect is filled with the aforementioned tissues. 18 patients with well established anterior instability were subject to this technique between March 2005 and December 2008. The follow-up time was 6 to 36 months (average 18 months). All were evaluated using the Rowe protocol for shoulder instability which assess stability, ROM & shoulder functionality. In 13 patients the outcome was assessed as excellent, in 4 good & in 1 average. In one patient, post-op stiffness was developed which managed successfully with conservative means. The arthroscopic technique of “remplissage” is an innovative choice in the armamentarium of treatment of anterior traumatic instability with concomitant Hill-Sachs lesion. The results of this technique are excellent regarding the recurrence rate of anterior instabiliy (in our series there was none episode of recurrent instability during the study period)

Purpose. To describe the geometric variables of the posterosuperior humeral-head (Hill-Sachs) lesion and analyze their relationship with patient clinical variables. Method. Twenty-eight patients with anteroinferior instability and substantial Hill-Sachs lesions were evaluated using arthro-computer tomography (CT) scans. The images were studied with the OSIRIX software, and the following lesion variables were measured: depth, length, width, volume, surface area, and width/depth ratio. Moreover, the ratio of the humeral heads total volume over the volume under its joint surface was calculated to express the lesions severity as the compromised fraction of the humeral heads articular segment. The above data was statistically analyzed in relation to the total number of instability episodes, the distinction between dislocations and subluxations, and the type of sport played. Results. The lesions had an mean depth of 7.3 mm, length of 19.9 mm, and width of 19.7 mm. The mean loss in humeral-head surface area was 3.83 cm2. The mean loss in humeral-head volume was 1.4 cm3, which equates to 2.2% of the total volume and 6.9% of the volume fraction under the joint surface. A linear correlation was found between lesion volume and the number of dislocations. Another significant relationship was identified between higher width/depth ratios and the subluxation group. None of the other analyses revealed any statistically significant correlations. Conclusion. In addition to providing useful descriptive data on Hill-Sachs lesions, this study is the first to demonstrate a significant correlation between lesion severity and the number of instability episodes. It also reveals the occurrence of significantly shallower lesions in the shoulders of subluxators compared to those of dislocators, which (as later studies may show) may have important implications on the therapeutic approach to these distinct types of shoulder instability

Background. The functional outcome and risk of recurrence following arthroscopic stabilisation for recurrent anterior shoulder instability is poorly defined in large prospective outcome studies. This is the first study to prospectively evaluate these outcomes in patients who have been treated using this technique. Methods. We performed a prospective study of a consecutive series of 302 patients (265 men and 37 women, mean age 26.4 years) who underwent 311 (9 bilateral) arthroscopic Bankart repairs for recurrent anterior instability. Patients were evaluated preoperatively and postoperatively at 6 months, and annually thereafter. The chief outcome measures were risk of recurrence and the two-year functional outcomes (assessed using the WOSI and DASH scores). Results. On survival analysis, the overall re-dislocation rate after surgery was 13.5% (42/311 shoulders). The median time to recurrence was 12 months (range 3 to 110 months) and 55% of these developed recurrent instability within 1 year of their surgery. The median follow-up in those patients who did not re-dislocate was 70 months. There was a significant improvement in the WOSI and DASH scores at 2 years postoperatively of 21.4 and 9.9 points respectively (both p<0.001). The risk of redislocation was significantly increased by the presence of glenoid bone loss associated with or without a Hill-Sachs lesion, and the type and engagement of a Hill-Sachs lesion on arthroscopic examination (all p<0.001). However, the risk in these sub-groups was lower than that reported in previous studies. A multivariate model was produced from these parameters to estimate the risk of recurrence at the time of primary surgery. Conclusions. The majority of patients have successful functional outcomes and relatively low risk of recurrence following arthroscopic stabilisation. The identification of preoperative factors which increase the risk of instability has enabled us to better counsel patients of their risk of failure following arthroscopic repair

Acute Hill-Sachs (HS) reduction represents a potential alternative method to remplissage for the treatment of an engaging HS lesion. The purpose of this study is to biomechanically compare the stabilising effects of a acute HS reduction technique and remplissage in a complex instability model. This was a comparative cadaveric study of 6 shoulders. For the acute HS lesion, a unique model was used to create a 30% defect, compressing the subchondral bone while preserving the articular surface in a more anatomic fashion. In addition, a 15% glenoid defect was made in all specimens. The HS lesion was reduced through a lateral cortical window with a bone tamp, and the subchondral void was filled with Quickset (Arthrex) bone cement to prevent plastic deformation. Five scenarios were tested; intact specimen, bipolar lesion, Bankart repair, remplissage with Bankart repair and HS reduction technique with Bankart repair. Translation, kinematics and dislocation events were recorded. For all 6 specimens no dislocations occurred after either remplissage or the reduction technique. At 90 degrees of abduction and external rotation (ABER), anterior-inferior translation was 11.1 mm (SD 0.9) for the bipolar lesion. This was significantly reduced following both remplissage (5.1±0.7mm; p<0.001) and HS reduction (4.4±0.3mm; p<0.001). For anterior-inferior translation there was no significant difference in translation between the reduction technique and remplissage (p=0.91). At 90 degrees of ABER, the intact specimens average joint stiffness was 7.0±1.0N/mm, which was not significantly different from the remplissage (7.8±0.9 N/mm; p=0.9) and reduction technique (9.1±0.6 N/mm; p=0.50). Compared with an isolated Bankart repair, the average external rotation loss after also performing a remplissage procedure was 4.3±3.5 deg (p=0.65), while average ER loss following HS reduction was 1.1±3.3 deg (p=0.99). There was no significant difference in external rotation between remplissage and the reduction technique (p=0.83). Similar joint stability was conferred following both procedures, though remplissage had 3.2-degree loss of ER in comparison. While not statistically significant, even slight ER loss may be clinically detrimental in overhead athletes. Overall, the acute reduction technique is a more anatomic alternative to the remplissage procedure with similar ability to prevent dislocation in a biomechanical model, making it a viable treatment option for engaging Hill-Sachs lesions

Aims

The Bankart and Latarjet procedures are two of the most common surgical techniques to treat anterior shoulder instability with satisfactory clinical and functional outcomes. However, the outcomes in the adolescent population remain unclear, and there is no information regarding the arthroscopic Latarjet in this population. The purpose of this study was to evaluate the outcomes of the arthroscopic Bankart and arthroscopic Latarjet procedures in the management of anterior shoulder instability in adolescents.