Hill-Sachs Off-track Lesions as Risk Factor for Recurrence of Instability After Arthroscopic Bankart Repair

Instability Severity Index Score predicts recurrent shoulder instability after arthroscopic Bankart repair

PURPOSE

The Instability Severity Index (ISI) Score was developed to preoperatively assess the risk of recurrent shoulder instability after an arthroscopic Bankart repair. This study aims to validate the use of ISI Score for predicting the risk of recurrence after an arthroscopic Bankart repair in a heterogeneous population and proposes an appropriate cut-off point for treating patients with an arthroscopic Bankart repair or otherwise.

METHODS

This study analysed 99 shoulders after a traumatic dislocation that underwent arthroscopic Bankart repair with at least 3 years follow-up. Patients were divided into subcategories based on their respective ISI Score. Recurrence includes either a postoperative dislocation or perceived instability.

RESULTS

The overall recurrence rate was found to be 26.3%. A significant correlation was identified between ISI Score and the recurrence rate (odds ratio [OR]: 1.545, 95% confidence interval [CI]: 1.231-1.939, p < 0.001). Furthermore, ISI Score 4-6 (OR: 4.498, 95% CI: 1.866-10.842, p < 0.001) and ISI Score > 6 (OR: 7.076, 95% CI: 2.393-20.924, p < 0.001) both had a significantly higher risk of recurrence compared to ISI Score 0-3. In ISI Score subcategories 0-3, 4-6 and >6, the recurrence rate was, respectively, 15.4%, 40.7% and 71.4%.

CONCLUSION

ISI Score has predictive value in determining the recurrence risk of shoulder instability following an arthroscopic Bankart repair in a heterogeneous population. Based on the findings of this study, we recommend using arthroscopic Bankart repair in patients with ISI Score 0-3. Clinical and shared decision-making are essential in the group with ISI Score 4-6, since the recurrence rate is significantly higher than in patients with ISI Score 0-3. Arthroscopic Bankart repair is not suitable for patients with ISI Score > 6.

LEVEL OF EVIDENCE

Level III.

Understanding the Remplissage: History, Biomechanics, Outcomes, and Current Indications

PURPOSE OF REVIEW

Arthroscopic remplissage has continued to gain popularity as an adjunct to Bankart repair for patients with anterior shoulder instability. Although the original remplissage technique was described over 15 years ago, our understanding of when and how to use this procedure continues to evolve. This article provides a review of how remplissage affects shoulder biomechanics, compares clinical outcomes between remplissage and other procedures for shoulder instability, and discusses current indications for remplissage.

RECENT FINDINGS

Current research focuses on the use of remplissage across a wide range of glenoid bone loss. Remplissage appears effective at preventing recurrent instability in patients with glenoid bone loss up to 15% of the glenoid width. However, once glenoid bone exceeds 15%, outcomes tend to favor bony reconstruction procedures such as Latarjet. Results of biomechanical studies examining shoulder range of motion (ROM) after remplissage are mixed, though clinical studies tend to report no significant limitations in ROM when remplissage is added to a Bankart repair. Adding a remplissage to conventional Bankart repair may improve clinical outcomes and lower rates of recurrent instability without significantly altering shoulder ROM. However, surgeons should recognize its limitations in treating patients with large amounts of glenoid bone loss and should be prepared to discuss alternative procedures on a case-by-case basis. Absolute indications and contraindications for remplissage are not well defined currently and require further scientific research.

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 2 landmarks. Although 3-dimensional computed tomography is the most accurate and widely used method to assess on/off-track lesions, our interest gradually is shifting toward magnetic resonance imaging (MRI), which has no radiation concern. The current magnetic resonance method is still under way. There are various risk factors influencing the recurrent instability after surgery. The glenoid track concept deals with only 1 of these factors, that is, instability caused by bony lesions. Therefore, the following 2 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 score. This new scoring system is expected to increase the predictive potential of the scoring system, and accordingly to enhance clinical decision-making.

Glenoid track and subcritical Hill-Sachs lesion

Background

We have proposed the concept of glenoid track ("on-track/off-track" lesion) to evaluate the risk of engagement of the Hill-Sachs lesion with the glenoid after arthroscopic Bankart repair. This concept has been widely used and many clinical validation studies have been reported. To measure the glenoid track width, we have recommended to use 3-dimensional computed tomography (CT) images. However, the CT method has the issue of radiation exposure and involves time and effort to make 3-dimensional CT images from 2-dimensional images. For these reasons, there are several reports describing the measurement method using magnetic resonance imaging. Recently, the threshold of the critical glenoid bone loss becomes lower. A zone of bone loss below the critical size is called "subcritical bone loss", which might be related to deterioration of quality of life and bone grafting is recommended. We applied the concept of "subcritical bone loss" to the glenoid track. Patients with "on-track" lesions can be divided into 2 subgroups: those with a "peripheral-track" lesion (most medial 1/4) and those with a "central-track" lesion (the rest 3/4). More recently, similar evaluation methods to evaluate the risk of "off-track" lesions have been reported: ''distance to dislocation'' and "Hill-Sachs interval/glenoid track ratio". Also, similar concept to "peripheral-track" lesion, "near-track" lesion was reported. The concept of "peripheral-track" lesion is a concept of assessing an "on-track" lesion which is very close to the medial margin of the glenoid track (subcritical bone loss).

Methods

Similar evaluation methods to evaluate the risk of "off-track" or "peripheral-track" lesions were proposed in the literature. A review was performed by searching PubMed. Journal articles published between January 2014 and January 2023 were taken into account. They were compared and their differences were explained.

Results

The "near-track" lesion concept is similar to "peripheral-track" lesion. However, the cutoff value is different: Hill-Sachs occupancy ≥ 75% is the "peripheral-track" lesion, whereas "distance to dislocation" < 8 mm is the "near-track" lesion.

Conclusion

We introduced update of the glenoid track concept including the evaluation method, peripheral-track lesion, and its clinical application.

The glenoid track concept is insufficient to predict Bankart failures: a computed tomography scan study

Background

The glenoid track concept identifies patients with "off-track" (engaging) Hill-Sachs lesions (HSLs) as poor candidates for arthroscopic Bankart repair (ABR) due to the high risk of shoulder instability recurrence.

Purpose

To retrospectively calculate the glenoid track index, using preoperative computed tomography (CT) scans, in a cohort of patients with failed ABR. We hypothesized that all patients with a failed ABR would have engaging ("off-track") HSLs on preoperative CT scan.

Type of Study

CT scan study.

Methods

Preoperative CT scan of 45 patients, seen in our facility for failed ABR, was used to retrospectively calculate the glenoid track index. The risk of recurrence was also calculated for each patient using Instability Severity Index Score (ISI-Score) and Glenoid Track Instability Management Score (GTIMS). There were 37 failed isolated ABRs and 8 associated HS remplissage. The mean t age at surgery was 24 years (range, 15-52) and instability recurred at a mean of 29 months postoperative (range, 3-167).

Results

Preoperative CT scan imaging identified "off-track" bony lesions in 85% of patients (38/45) and "on-track" lesions in 15% (7/45). No significant differences were noted between the 2 groups (off-track vs. on-track) regarding patient age, hyperlaxity, sports participation, size of HS lesion, or ISI-Score. The mean glenoid bone loss was 15.7% (range, 4-36%) with mean HS width was greater than 20 mm in 66% of CT scans. The preoperative ISI-Score was predictive of failures (>3 points in all patients) with no difference between on-track and off-track patients (6.3 ± 1.7 vs. 6.6 ± 1.7, P = .453). By contrast, the GTIMS did not predict failures as there was a significant difference between GTIMS for on-track and off-track patients (2.1 ± 1.3 vs. 6.6 ± 1.7).

Conclusions

The glenoid track concept alone is insufficient to predict Bankart failures: in the present series of failed ABR, 15% of shoulders had "on-track" (non-engaging) lesions on preoperative CT scan. In patients, with "on-track" bony lesions, the ISI-Score is a useful predictive tool to detect patients at risk of failure, while the GTIMS is not.

Anterior Shoulder Stabilization Using Single Needle-Assisted Outside-In Remplissage Technique and Bankart Repair

Arthroscopic repair of Bankart injury is the first choice for the treatment of anterior shoulder instability. How to avoid recurring shoulder joint dislocation is a challenge, especially when combined with Hill-Sachs lesions. The arthroscopy technology allows for broader vision and less surgical trauma but is limited by a smaller operating space. At present, extensive descriptions about the surgical procedure of arthroscopic Bankart repair have been published. In this Technical Note, we describe the use of remplissage filling with Hill-Sachs lesion combined with Bankart repair to further improve the surgical accuracy and clinical efficacy. In particular, the application of single needle-assisted outside-in remplissage technique and Bankart repair is introduced in detail.

Validating the Glenoid Track Concept Using Dynamic Arthroscopic Assessment

Background

Failure after isolated Bankart repair has led surgeons to consider when to address the Hill-Sachs lesion, which is thought to be a contributor to recurrent instability. One approach utilizes the glenoid track concept to determine whether a Hill-Sachs lesion is classified as "off-track," suggesting that the addition of a remplissage procedure may aid stability. However, the accuracy and reliability of using this approach require validation using an appropriate reference.

Purpose

To determine the accuracy and reliability of using the glenoid track concept against dynamic arthroscopic assessment of Hill-Sachs lesion engagement.

Study Design

Cohort study (diagnosis); Level of evidence, 3.

Methods

A total of 49 patients undergoing arthroscopic Bankart repair surgery for recurrent traumatic anterior shoulder instability were enrolled in this diagnostic validation study. Shoulders were classified as on-track or off-track using 3-dimensional computed tomography (3DCT) and static arthroscopic measurements. These classifications were compared with dynamic arthroscopic assessment (engagement of the Hill-Sachs lesion on the anterior glenoid rim in the 'athletic position') to determine their accuracy and reliability.

Results

The 3DCT-based measurements to determine glenoid track status had a higher positive predictive value (66% vs 42%), higher specificity (47% vs 42%), and higher accuracy (65% vs 59%) compared with static arthroscopic measurements. Static arthroscopic measurements to determine glenoid track status had a higher negative predictive value (96% vs 64%) and higher sensitivity (96% vs 81%) compared with 3DCT-based measurements. Interrater reliability (Krippendorff α) was 'fair' for determining the glenoid track status using 3DCT (0.368; 95% CI, 0.217-0.519) and 'moderate' for static arthroscopic measurements (0.523; 95% CI, 0.364-0.666). Intrarater reliability (intraclass correlation coefficient [ICC] 3,k) was 'moderate' for 3DCT measurements (0.660; 95% CI, 0.444-0.798) and 'good' for static arthroscopic measurements (0.769; 95% CI, 0.629-0.862).

Conclusion

Determining glenoid track status using either 3DCT or static arthroscopic measurements yielded moderate accuracy and reliability. Surgeons using the glenoid track concept to aid surgical decision-making in traumatic recurrent anterior shoulder instability should utilize 3DCT or static arthroscopic measurements with caution.

Association of Instability History and Off-Track Hill-Sachs Lesions in Anterior Shoulder Instability

Background

The glenoid track concept is now widely accepted, and its evaluation is considered essential for making decisions about surgery.

Purpose

To define preoperative descriptive data and clinical and functional features in patients with anterior glenohumeral instability according to glenoid track status and to analyze the influence of off-track Hill-Sachs (HS) lesions on preoperative shoulder function.

Study Design

Case-control study; Level of evidence, 3.

Methods

Preoperative magnetic resonance imaging or computed tomography scans were used to measure the glenoid track. Descriptive data and preoperative objective and subjective clinical and functional features were compared between patients with on-track HS lesions versus off-track HS lesions. Multivariate regression analysis was conducted to identify potential risk factors for off-track HS lesion development.

Results

A total of 235 patients (201 men, 34 women; mean age, 29.6 ± 8.6 years) were included- 134 shoulders (57%) with on-track HS lesions and 101 shoulders (43%) with off-track HS lesions. Age <20 years at first dislocation, number of dislocations, and ≥2 years between first dislocation and surgery were significantly different between the study groups (P = .005, P = .0001, and P = .01, respectively). Regarding these characteristics, the odds ratios for the risk of developing an off-track lesion were 2.67 (95% CI, 1.2-5.99)-1.2 times higher for each additional instability episode (95% CI, 1.025-1.14) and 2.42 times higher (95% CI, 1.176-4.608) for patients whose first dislocation was ≥2 years before surgery, respectively. Patients with off-track HS lesions had a significantly greater degree of instability (P = .04), worse Rowe scores (48.8 ± 15.3 vs 54.8 ± 28.3 for on-track HS lesions; P = .04), and lower Western Ontario Shoulder Instability scores (975 ± 454 vs 1179 ± 428 for on-track HS lesions; P = .01).

Conclusion

Characteristics related to a history of instability (age <20 years at first instability episode, larger number of dislocations, ≥2 years between first dislocation and surgery) were found to be risk factors for the development of an off-track HS lesion in this study. Off-track lesions led to a higher degree of instability and worse objective and subjective preoperative shoulder function versus on-track HS lesions.

Current Concepts in the Measurement of Glenohumeral Bone Loss

PURPOSE

The extent of glenohumeral bone loss seen in anterior shoulder dislocations plays a major role in guiding surgical management of these patients. The need for accurate and reliable preoperative assessment of bone loss on imaging studies is therefore of paramount importance to orthopedic surgeons. This article will focus on the tools that are available to clinicians for quantifying glenoid bone loss with a focus on emerging trends and research in order to describe current practices.

RECENT FINDINGS

Recent evidence supports the use of 3D CT as the most optimal method for quantifying bone loss on the glenoid and humerus. New trends in the use of 3D and ZTE MRI represent exciting alternatives to CT imaging, although they are not widely used and require further investigation. Contemporary thinking surrounding the glenoid track concept and the symbiotic relationship between glenoid and humeral bone loss on shoulder stability has transformed our understanding of these lesions and has inspired a new focus of study for radiologists and orthopedist alike. Although a number of different advanced imaging modalities are utilized to detect and quantify glenohumeral bone loss in practice, the current literature supports 3D CT imaging to provide the most reliable and accurate assessments. The emergence of the glenoid track concept for glenoid and humeral head bone loss has inspired a new area of study for researchers that presents exciting opportunities for the development of a deeper understanding of glenohumeral instability in the future. Ultimately, however, the heterogeneity of literature, which speaks to the diverse practices that exist across the world, limits any firm conclusions from being drawn.

Anatomic risk factors for arthroscopic Bankart repair failure: A case-control study comparing failure and non-failure groups in an Asian population

Introduction

Post-arthroscopic Bankart repair failure/re-dislocation rates are influenced by several risk factors, including anatomic defects. There is limited evidence on the role of anatomic defects, especially for Hill-Sachs size in on-track lesions. This study aimed to assess glenoid bone loss, Hill-Sachs lesion and labral tear size and evaluate their contribution to post-operative instability after a primary repair.

Material and methods

Across 169 patients with on-track Bankart lesions who underwent primary arthroscopic Bankart repair from 2010 to 2015, this study matched 14 failure with 14 non-failure cases based on age/gender. Patient demographics, pre-operative radiological parameters (including size of glenoid bone loss and Hill-Sachs lesion) and labral tear size were compared between the failure and non-failure groups.

Result

All patients were male with a mean age of 21.01 ± 4.97. Significantly greater glenoid bone loss (p = 0.024) and labral tear size (p = 0.039) were found in the failure group. However, there was no significant difference in mean volume of Hill-Sachs lesion between the two groups (p = 0.739).

Conclusion

Extensive glenoid bone loss and labral tears are risk factors for post-arthroscopic Bankart failure. However, the size of Hill-Sachs lesion is not a risk factor for failure, in a specific group of on-track Hill-Sachs lesions.

Level of evidence

Retrospective Study, Level IV.

Revision Arthroscopic Bankart Repair Results in High Failure Rates and a Low Return to Duty Rate Without Recurrent Instability

PURPOSE

The purpose of this study was to determine, in a military population without critical bone loss, the rate of recurrent instability after revision arthroscopic stabilization for failed primary arthroscopic Bankart repair.

METHODS

Forty-one revision arthroscopic stabilizations were performed at a single military institution between 2005 to 2016 for recurrent anterior shoulder instability after primary arthroscopic Bankart repair. Minimum follow-up was 2 years, and shoulders with glenoid bone loss >20% were excluded. The primary outcome of interest was the incidence of failure, defined by recurrent instability.

RESULTS

Age at revision surgery averaged 22.9 ± 4.3 years, and 88% were either service academy cadets or active duty combat arms soldiers. Mean follow-up was 7.8 years. Twenty-three patients (56%) returned to duty without recurrent instability after revision arthroscopic stabilization. Eighteen patients (44%) experienced recurrent instability after return to duty. Glenoid bone loss averaged 6.2% (95% confidence interval [CI], 3.2%-9.2%) in the successful group and 5.7% (95% CI, 3.1%-8.3%) in the failure group (P = .808).

CONCLUSIONS

Revision arthroscopic stabilization of failed primary arthroscopic Bankart repair has a failure rate of 44% in a young military population. The similar amounts of bone loss between groups indicates that bone loss is not the primary determinant of failure in revision arthroscopic stabilization.

LEVEL OF EVIDENCE

IV, Case Series.

Management of off-track Hill-Sachs lesions in anterior glenohumeral instability

Bone loss has been identified as a risk factor for recurrent shoulder dislocations or failure after soft tissue repair. Although the range for "critical" bone loss is yet to be determined, glenoid and humeral bone defects should not be regarded as independent problems, but the interaction between them during shoulder motion should be evaluated as suggested by the glenoid track concept. The glenoid track concept is now widely accepted and considered essential for making decisions about surgery. Soft-tissue procedures usually work well in patients with on-track Hill-Sachs lesions but in off-track lesions do not. In this situation additional procedures should be performed.Different surgical options have been described to address off-track Hill-Sachs lesions, most commonly remplissage, Latarjet or free bone block procedures. Coracoid graft and free bone grafts convert the off-track Hill-Sachs lesion into on-track by lengthening the glenoid-track, whereas remplissage fill-in the humeral lesion so that it does not engage. In the setting of a Hill-Sachs lesion with little or no glenoid bone loss, remplissage has demonstrated satisfactory outcomes with a low complications and recurrence rate. Favorable results have been reported with glenoid bone grafting when managing isolated Hill-Sachs or bipolar lesions. Studies analyzing Latarjet and Eden-Hybinette procedures show that both procedures are safe and effective in the management of anterior glenohumeral instability. Attention should be paid to those patients with large bone defects not amenable to be restored with an isolated Latarjet that may be better addressed with an Eden-Hybinnete or adding a remplissage to the Latarjet procedure.

Arthroscopic Bankart Repair for Adolescent Anterior Shoulder Instability: Clinical and Imaging Predictors of Revision Surgery and Recurrent Subjective Instability

BACKGROUND

Multiple clinical and radiologic risk factors for recurrent instability after arthroscopic Bankart repair have been described. Humeral bone loss has gained more recent attention, particularly with respect to "off-track" lesions and increased rates of recurrent instability and revision surgery.

PURPOSE

To evaluate clinical and radiologic predictors of failure after arthroscopic Bankart repair in adolescents.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A single-institution retrospective study was performed in patients <19 years of age treated with arthroscopic Bankart repair from 2011 to 2017. Magnetic resonance imaging measurements of glenoid and humeral bone loss, the glenoid track, and the presence of off-track Hill-Sachs (HS) lesions were assessed. All patients had a minimum follow-up of 24 months and completed patient-reported outcome scores. Failure was defined as revision surgery or postoperative subjective instability.

RESULTS

A total of 59 patients (46 male, 13 female) with a median age of 16 years (range, 12-18 years) were included. Ten patients (17%) had revision surgery and 8 patients (14%) had subjective instability without revision surgery. No clinical or radiologic factors were significantly different between the failure cohort and the nonfailure cohort. Four patients (7%) measured off-track, and 2 of these patients experienced failure. A total of 38 patients (64%) were identified to have an HS defect. Subgroup analysis of these patients identified a greater HS interval (HSI) in patients who underwent revision surgery as compared with those patients who did not have revision surgery. Among patients with GT ratio ≥15 mm, there was a 50% rate of revision surgery. The Pediatric/Adolescent Shoulder Survey (PASS) and Single Assessment Numeric Evaluation (SANE) scores at the final follow-up were not significantly different among patients with or without revision surgery. However, those with subjective instability who had not undergone revision surgery had significantly lower PASS and SANE scores as compared with the remainder of the cohort.

CONCLUSION

Of the adolescents in this cohort, 31% either had revision surgery (17%) or reported subjective feelings of instability (14%) after arthroscopic Bankart repair. Off-track instability was identified in 7% of the cohort but was not predictive of failure. Among the subgroup of patients with an HS defect, those who underwent revision surgery had a significantly larger HSI.

Long-term recurrence rate in anterior shoulder instability after Bankart repair based on the on- and off-track concept

BACKGROUND

Since its first proposal, the concept of on- and off-track lesions in anterior shoulder instability has gained clinical relevance as a tool to predict the failure rate of arthroscopic Bankart repair. Current literature only reports either short-term follow-up or long-term results of small sample sizes. The aim of this study was to provide a long-term evaluation of recurrent instability following arthroscopic Bankart repair in a large cohort using the on-track vs. off-track concept as a predictor for failure.

METHODS

We retrospectively analyzed 271 patients who underwent primary arthroscopic Bankart repair for anterior shoulder instability between 1998 and 2007. All patients with a minimum follow-up of 78 months and a preoperative computed tomographic (CT) or magnetic resonance imaging (MRI) scan were included into the study. Preoperative CT and/or MRI scans were used to determine the glenoid track and width of Hill-Sachs lesion. Recurrence of instability was defined as presence of instability symptoms (dislocation, subluxation, and/or apprehension) or revision surgery (stabilization procedure) and was assessed as the primary outcome parameter.

RESULTS

The glenoid track of 163 shoulders was assessed (female n = 51, male n = 112) with a mean follow-up of 124 months (99.4-145.6, standard deviation = 2.5) and a mean age of 24 years (20-34.). An off-track Hill-Sachs lesion was found in 77 cases (47%), and in 86 cases (53 %) it was on-track. The rate of recurrent instability in the off-track group was 74% (n = 57) compared with 27% (n = 23) in the on-track group (P < .001). The overall rate of revision surgery due to instability was 29% (n = 48) after a mean time of 50.9 months (±42.8) following Bankart repair. The rate of revision surgery in the off-track group was 48% (n = 37) after a mean of 53.5 months (±42.0) vs. 13% (n = 11) after 42.3 months (±46.3) in the on-track group (P < .001).

CONCLUSION

This study shows that the on- and off-track concept helps to distinguish patients for whom an isolated arthroscopic Bankart repair yields long-term benefits. Because of the high rate of recurrent instability in the off-track group, an off-track lesion should be treated surgically in such a way that the off-track lesion is converted into an on-track lesion.

First-time traumatic anterior shoulder dislocation: current concepts

The management of first-time traumatic anterior shoulder dislocations has been a topic of extensive study yet remains controversial. Development of a treatment plan requires an understanding of patient-specific considerations, including demographics, functional demands, and extent of pathology. Each of these can influence rates of recurrence and return to activity. The purpose of this review is to provide a framework for decision-making following a first-time anterior shoulder dislocation, with particular focus on the high-risk young and athletic population. A summary of surgical treatment options and their outcomes is outlined, along with future biomechanical and clinical perspectives.

Open anatomical glenoid reconstruction with an iliac crest bone autograft effectively resolves off-track Hill-Sachs lesions to on-track lesions

INTRODUCTION

The purpose of this study was to determine if "off-track" Hill-Sachs lesions in patients with dynamic anteroinferior instability were transformed into "on-track" lesions using iliac bone autografts with screw fixation. The secondary purpose was to observe if postoperative bony remodeling would occur over time, resulting in recurrent "off-track" Hill-Sachs lesions with corresponding instability.

MATERIALS AND METHODS

We retrospectively reviewed clinical and CT records of 8 patients with an "off-track" Hill-Sachs lesion who underwent open anatomical glenoid reconstruction with an iliac crest bone autograft. Hill-Sachs lesions, glenoid track widths, and glenoid surface areas were measured on a preoperative and two postoperative (6 weeks, ≥ 2 years) 3D-CT models to determine graft resorption over time. All patients were available for postoperative clinical and CT final follow-up 3 years (2-4 years) postoperatively.

RESULTS

In all patients, the Hill-Sachs lesions were "on-track" 6 weeks postoperatively and remained "on-track" at final-follow-up. Compared to preoperative values, the glenoid track width and glenoid surface area both were higher 6 weeks postoperatively (p < 0.001 and p = 0.023, respectively) and at final follow-up (p < 0.001 and p = 0.023, respectively). Whereas the glenoid track width between 6 weeks and final follow-up showed no decrease (p = 0.234), glenoid surface area tended to decrease (p = 0.055). The median SSV was 93 points (85-95 points), the Rowe score 90 points (80-100 points) and the WOSI 1980 points (1783-2067 points) at final follow-up. No recurrent dislocations or subluxations were observed.

CONCLUSIONS

An open anatomical glenoid reconstruction with an iliac crest bone autograft technique using screw fixation effectively transformed "off-track" Hill-Sachs lesions to "on-track" lesions, resulting in good short-term clinical outcomes. Whereas glenoid surface area tended to be reduced by bony remodeling processes over time, the glenoid track width did not decrease at final follow-up and consequently no recurrence of "off-track" lesions occurred.

LEVEL OF EVIDENCE

Case series; Level of evidence, IV.

Humeral and Glenoid Version in Reverse Total Shoulder Arthroplasty: A Systematic Review

There is increasing interest in reverse total shoulder arthroplasty (RTSA) as a reliable treatment for arthritic, rotator cuff deficient shoulders. Humeral and glenoid version are controversial parameters that can influence internal and external rotation, muscular forces, and implant stability as outcomes of RTSA. The aim of this study was to obtain an overview of the current knowledge on the effect of both humeral component version and glenoid component version and give recommendations on their most optimal degree for RTSA. A comprehensive quantitative review of the published literature on the effect of humeral version and glenoid version in RTSA was performed, to identify its influence on the range of movement, muscle forces, and intrinsic stability of the reverse prosthesis. Eleven studies were included: nine were biomechanical studies, one was a clinical-radiographic study, and one was an implant design consideration. Anterior stability can be improved by implanting the humeral component in neutral or with some anteversion. Glenoid component retroversion has been proven to reduce the likelihood of subluxation, while increasing ER and ROM at the same time. The study was conducted considering 5° anteversion; neutral; and 5°, 10°, and 20° retroversion of the glenoid component. Although a final opinion has not been yet expressed on the matter, the general consensus tends to agree on restoring 0° to 20° of retroversion of the humeral and glenoid component to yield the best outcomes.

Anterior glenoid rim erosion in the early stage after arthroscopic Bankart repair affects postoperative recurrence

Background

Recent studies reported that anterior glenoid rim erosion can occur in the early period after arthroscopic Bankart repair (ABR) for traumatic anterior shoulder instability. However, it is unknown whether such erosion is a risk factor for postoperative recurrence. This study evaluated risk factors for postoperative recurrence after ABR, specifically aiming to elucidate whether reduction of postoperative glenoid width due to anterior glenoid rim erosion is one of such factors.

Methods

A total of 220 shoulders that underwent ABR alone between 2013 and 2020 were retrospectively investigated. Patient age at surgery, whether the patient was a collision/contact athlete, anchor placement, preoperative glenoid bone defect (%), localization of the Hill-Sachs lesion, and change of glenoid width (%) in the 6 months after surgery were investigated for their statistical relation to recurrence by univariate and multiple logistic regression analysis.

Results

Postoperative recurrence occurred in 32 of 220 shoulders (14.5%). In univariate analysis, being a collision/contact athlete was the only variable with a significant effect on recurrence (odds ratio [OR], 2.555; 95% confidence interval [CI], 1.123-5.814; P = .03). Change of glenoid width reduction was larger in those with recurrence than without recurrence, but the difference was not statistically significant (-7.0 ± 6.6% vs. -5.0 ± 9.3%; P = .14). However, in multivariate logistic analysis, preoperative glenoid bone defect (%) (adjusted unit OR, 1.076; 95% CI, 1.018-1.137; P = .010) and postoperative change of glenoid width (%) (adjusted unit OR, 0.946; 95% CI, 0.900-0.994; P = .028) had a significant influence on postoperative recurrence.

Conclusion

Glenoid width reduction due to anterior glenoid rim erosion after ABR is a risk factor for recurrence.

Arthroscopic Remplissage for the Treatment of Anterior Shoulder Instability: Current and Evolving Concepts

➢

A Hill-Sachs lesion (HSL) is a compression fracture on the posterolateral humeral head that can increase the risk of recurrent shoulder instability after isolated arthroscopic Bankart repair.

➢

Remplissage involves capsulotenodesis of the infraspinatus tendon and posterior capsule into the HSL to prevent its engagement with the glenoid rim through extra-articular conversion and restraint against humeral head anterior translation.

➢

The glenoid track concept can be applied preoperatively and intraoperatively to evaluate risk of recurrence and help direct clinical management options for recurrent shoulder instability.

➢

Recent literature supports expanding indications for remplissage to include patients with on-track HSLs who are at increased risk of recurrence including collision athletes, military personal, and patients with joint hyperlaxity.

➢

New techniques and suture constructs have demonstrated improved biomechanical strength while avoiding the need to access the subacromial space.

Bankart Repair With Remplissage Restores Better Shoulder Stability Than Bankart Repair Alone, and Medial or Two Remplissage Anchors Increase Stability but Decrease Range of Motion: A Finite Element Analysis

PURPOSE

To investigate the effects of the number and location of anchors for remplissage on postoperative glenohumeral biomechanics.

METHODS

A biomechanical study was conducted involving finite element model constructed based on data from the intact glenohumeral joint. Seven models were established, including a normal model, a model of Bankart lesion combined with "off-track" Hill-Sachs lesion, a model of Bankart repair alone, and 4 models of Bankart repair with remplissage based on different remplissage anchor numbers and locations. The effects of the number and location of the remplissage anchors on glenohumeral stability were studied through calculation and comparison of (1) the stress and its distribution on the joint capsule, cartilage, labrum and anchors as well as (2) the displacement of the humeral head.

RESULTS

Finite element analysis demonstrated that contact stress on the glenohumeral cartilage decreased when medial or 2 anchors were used and was minimized in the combined repair model with 2 medial anchors. The stress on remplissage anchors was greater when the anchors were placed medially. The humeral head displacement was maximized in the combined lesion model. The combined repair models with 2 medially placed anchors showed the largest slope on the force-displacement curve, indicating the largest strain on the humeral head.

CONCLUSIONS

Based on a finite element analysis, Bankart repair with remplissage restored better shoulder stability compared with Bankart repair alone in the treatment of anterior shoulder instability involving Bankart lesion combined with "off-track" Hill-Sachs lesion. When the anchor for remplissage was medially placed or 2 anchors were used, the stability of the glenohumeral joint increased but with a loss of range of motion.

CLINICAL RELEVANCE

The results of this study will assist in choosing the number and location of anchors for remplissage during shoulder stabilization surgery although with some limitations.

Inconsistencies in Controlling for Risk Factors for Recurrent Shoulder Instability After Primary Arthroscopic Bankart Repair: A Systematic Review

BACKGROUND

Failure rates after arthroscopic shoulder stabilization are highly variable in the current orthopaedic literature. Predictive factors for risk of failure have been studied to improve patient selection, refine surgical techniques, and define the role of bony procedures. However, significant heterogeneity in the analysis and controlling of risk factors makes evidence-based management decisions challenging.

PURPOSE

The goals of this systematic review were (1) to critically assess the consistency of reported risk factors for recurrent instability after arthroscopic Bankart repair, (2) to identify the existing studies with the most comprehensive inclusion of confounding factors in their analyses, and (3) to give recommendations for which factors should be reported consistently in future clinical studies.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the literature was performed in accordance with the PRISMA guidelines. An initial search yielded 1754 titles, from which 56 full-text articles were screened for inclusion. A total of 29 full-text articles met the following inclusion criteria: (1) clinical studies regarding recurrent anterior shoulder instability; (2) surgical procedures performed including arthroscopic anterior labral repair; (3) reported clinical outcome data including failure rate; and (4) assessment of risk factors for surgical failure. Further subanalyses were performed for 15 studies that included a multivariate analysis, 17 studies that included glenoid bone loss, and 8 studies that analyzed the Instability Severity Index Score.

RESULTS

After full-text review, 12 of the most commonly studied risk factors were identified and included in this review. The risk factors that were most consistently significant in multivariate analyses were off-track lesions (100%), glenoid bone loss (78%), Instability Severity Index Score (75%), level of sports participation (67%), number of anchors (67%), and younger age (63%). In studies of bone loss, statistical significance was more likely to be found using advanced imaging, with critical bone loss thresholds of 10% to 15%. Several studies found predictive thresholds of 2 to 4 for Instability Severity Index Score by receiver operating characteristic or multivariate analysis.

CONCLUSION

Studies reporting risk factors for failure of arthroscopic Bankart repair often fail to control for known confounding variables. The factors with the most common statistical significance among 15 multivariate analyses are off-track lesions, glenoid bone loss, Instability Severity Index Score, level of sports participation, number of anchors, and younger age. Studies found significance more commonly with advanced imaging measurements or arthroscopic assessment of glenoid bone loss and with lower thresholds for the Instability Severity Index Score (2-4). Future studies should attempt to control for all relevant factors, use advanced imaging for glenoid bone loss measurements, and consider a lower predictive threshold for the Instability Severity Index Score.

Comparison of computed tomography and 3D magnetic resonance imaging in evaluating glenohumeral instability bone loss

BACKGROUND

To determine whether the addition of 3-dimensional (3D) magnetic resonance imaging (MRI) to standard MRI sequences is comparable to 3D computed tomographic (CT) scan evaluation of glenoid and humeral bone loss in glenohumeral instability.

METHODS

Eighteen patients who presented with glenohumeral instability were prospectively enrolled and received both MRI and CT within 1 week of each other. The MRI included an additional sequence (volumetric interpolated breath-hold examination [VIBE]) that underwent postprocessing for reformations. The addition of a VIBE protocol, on average, is an additional 4-4.5 minutes in the scanner. CT data also underwent 3D postprocessing, and therefore each patient had 4 imaging modalities (2D CT, 2D MRI, 3D CT reformats, and 3D MRI reformats). Each sequence underwent the following measurements from 2 separate reviewers: glenoid defect, glenoid defect percentage, humeral defect, humeral defect percentage, and evaluation of glenoid track and version. Paired t tests were used to assess differences between imaging modalities and χ² for glenoid track. Intra- and interobserver reliability were evaluated. Bland-Altman tests were also performed to assess the agreement between CT and MRI. In addition, we determined the cost of each imaging modality at our institution.

RESULTS

3D MRI measurements for glenoid and humeral bone loss measurements were comparable to 3D CT (Table 1). There were no significant differences for glenoid defect size and percentage, or humeral defect size and percentage (P > .05) (Table 2). Bland-Altman analysis demonstrated strong agreement, with small measurement errors for 3D CT and 3D MRI percentage glenoid bone loss. There was also no difference in evaluation for determining on vs. off track between any of the imaging modalities. Inter- and intrarater reliability was good to excellent for all CT and MRI measurements (r ≥ 0.7).

CONCLUSION

3D MRI measurements for bone loss in glenohumeral instability through use of VIBE sequence were equivalent to 3D CT. At our institution, undergoing MRI with 3D reconstruction was 1.67 times cheaper than MRI and CT with 3D reconstructions. 3D MRI may be a useful adjuvant to standard MRI sequences to allow concurrent soft tissue and accurate assessment of glenoid and humeral bone loss in glenohumeral instability.

Bony reconstruction after failed labral repair is associated with higher recurrence rates compared to primary bony reconstruction: a systematic review and meta-analysis of 1319 shoulders in studies with a minimum of 2-year follow-up

BACKGROUND

There is uncertainty with regard to the optimal revision procedure after failed labral repair for anterior shoulder instability. An overview of outcomes of these procedures with quantitative analysis is not available in literature. The aim of this review is (1) to compare recurrence rates after revision labral repair (RLR) and revision bony reconstruction (RBR), both following failed labral repair. In addition, (2) recurrence rates after RBR following failed labral repair and primary bony reconstruction (PBR) are compared to determine if a previous failed labral repair influences the outcomes of the bony reconstruction.

METHODS

Randomized controlled trials and cohort studies with a minimum follow-up of 2 years and reporting recurrence rates of (1) RBR following failed labral repair and PBR and/or (2) RLR following failed labral repair and RBR following failed labral repair were identified by searching PubMed, Embase/Ovid, Cochrane Database of Systematic Reviews/Wiley, Cochrane Central Register of Controlled Trials/Wiley, and Web of Science/Clarivate Analytics.

RESULTS

Thirteen studies met the inclusion criteria and comprised 1319 shoulders. Meta-analyses showed that RBR has a significantly higher recurrence rate than PBR (risk ratio [RR] 0.51, P < .008) but found no significant difference in the recurrence rates for RLR and RBR (RR 1.40, P < .49). Also, no significant differences were found between PBR and RBR in return to sport (RR 1.07, P < .41), revision surgery (RR 0.8, P < .44), and complications (RR 0.84, P < .53). Lastly, no significant differences between RLR and RBR for revision surgery (RR 3.33, P < .19) were found.

CONCLUSION

The findings of this meta-analyses show that (1) RBR does not demonstrate a significant difference in recurrence rates compared with RLR and that (2) RBR has a significantly higher recurrence rate than PBR.

The Role of Humeral Neck-Shaft Angle in Reverse Total Shoulder Arthroplasty: 155° versus <155°—A Systematic Review

The aim of this study was to have updated scrutiny of the influence of the humeral neck-shaft angle (HNSA) in patients who underwent reverse shoulder arthroplasty (RSA). A PRISMA-guided literature search was conducted from May to September 2021. Clinical outcome scores, functional parameters, and any complications were reviewed. Eleven papers were identified for inclusion in this systematic review. A total of 971 shoulders were evaluated at a minimum-follow up of 12 months, and a maximum of 120 months. The sample size for the "HNSA 155°" group is 449 patients, the "HNSA 145°" group involves 140 patients, and the "HSNA 135°" group comprises 291 patients. The HNSA represents an important variable in choosing the RSA implant design for patients with rotator cuff arthropathy. Positive outcomes are described for all the 155°, 145°, and 135° HSNA groups. Among the different implant designs, the 155° group show a better SST score, but also the highest rate of revisions and scapular notching; the 145° cohort achieve the best values in terms of active forward flexion, abduction, ASES score, and CMS, but also the highest rate of infections; while the 135° design obtains the best results in the external rotation with arm at side, but also the highest rate of fractures. High-quality studies are required to obtain valid results regarding the best prosthesis implant.

Motion Tracking Algorithms Based on Wearable Inertial Sensor: A Focus on Shoulder

Shoulder Range of Motion (ROM) has been studied with several devices and methods in recent years. Accurate tracking and assessment of shoulder movements could help us to understand the pathogenetic mechanism of specific conditions in quantifying the improvements after rehabilitation. The assessment methods can be classified as subjective and objective. However, self-reported methods are not accurate, and they do not allow the collection of specific information. Therefore, developing measurement devices that provide quantitative and objective data on shoulder function and range of motion is important. A comprehensive search of PubMed and IEEE Xplore was conducted. The sensor fusion algorithm used to analyze shoulder kinematics was described in all studies involving wearable inertial sensors. Eleven articles were included. The Quality Assessment of Diagnostic Accuracy Studies-2 was used to assess the risk of bias (QUADAS-2). The finding showed that the Kalman filter and its variants UKF and EKF are used in the majority of studies. Alternatives based on complementary filters and gradient descent algorithms have been reported as being more computationally efficient. Many approaches and algorithms have been developed to solve this problem. It is useful to fuse data from different sensors to obtain a more accurate estimation of the 3D position and 3D orientation of a body segment. The sensor fusion technique makes this integration reliable. This systematic review aims to redact an overview of the literature on the sensor fusion algorithms used for shoulder motion tracking.

Athletes with primary glenohumeral instability demonstrate lower rates of bone loss than those with recurrent instability and failed prior stabilization

BACKGROUND

The purpose of this study was to compare the preoperative magnetic resonance arthrography findings in patients who underwent glenohumeral stabilization with a history of primary instability, recurrent instability, or failed stabilization.

METHODS

All patients who presented with glenohumeral instability and underwent stabilization performed by a single surgeon in our institution between 2008 and 2020 were considered for inclusion in this study. The magnetic resonance arthrography findings of all patients were recorded. Imaging findings were compared between patients with primary instability, those with recurrent instability, and those with failed prior stabilization. P < .05 was considered statistically significant.

RESULTS

Overall, 871 patients were included, of whom 814 (93.5%) were male patients; the mean age was 23.1 years (range, 13-57 years). There were 200 patients with primary instability, 571 with recurrent instability, and 100 who required revision stabilization surgery, with no significant differences in demographic characteristics between the groups. A significantly higher amount of glenoid bone loss was noted in patients with recurrent instability (43.4%) and failed prior stabilization (56%) than in those with primary instability (26.5%) (P < .0001). Additionally, a significantly higher number of Hill-Sachs lesions were observed in patients with recurrent instability (70.1%) and failed prior stabilization (89%) than in those with primary instability (67.5%) (P < .0001). We found no significant differences between the groups regarding articular cartilage damage, glenolabral articular disruption, anterior labral periosteal sleeve avulsion, humeral avulsion of the glenohumeral ligaments, or superior labral anterior-posterior tears (P > .05).

CONCLUSION

Patients presenting for stabilization with recurrent instability or following a failed stabilization procedure have higher rates of glenohumeral bone loss than those with primary instability. Therefore, stabilization of primary instability, particularly in high-functioning athletes with a view to preventing recurrence, may reduce the overall progression of glenohumeral bone loss and potential subsequent inferior clinical outcomes.

Risk factors for recurrence after Bankart repair: a systematic review and meta-analysis

Background

The aim of this literature review was to identify preoperative risk factors associated with recurrent instability after Bankart repair.

Methods

The PubMed, Web of Science, Embase, and Cochrane Library databases were searched for potentially eligible articles. Two reviewers independently screened the titles and abstracts using prespecified criteria. Articles were included if they clearly stated the risk factors for recurrence after Bankart repair. Data on patient characteristics and recurrence rate were collected from each study. A random-effects model was used for the meta-analysis and the statistical analysis was performed using Review Manager 5.4 software.

Results

Nineteen studies that included 2922 participants met the inclusion criteria. The overall pooled prevalence of recurrent instability was 15.3% (range 6.9–42). The mean follow-up duration was 40.5 months (18–108). Twenty-one risk factors were identified, 10 of which were explored quantitatively. Statistically significant risk factors for recurrent instability following a Bankart procedure were age under 20 years (odds ratio [OR] 4.24, 95% confidence interval [CI] 2.8–96.23, p < 0.00001), a Hill-Sachs lesion (OR 3.61, 95% CI 2.06–6.33, p < 0.00001), a glenoid bone lesion (OR 2.8, 95% CI 1.96–4.01, p < 0.00001), shoulder hyperlaxity (OR 4.55, 95% CI 2.19–9.44, p < 0.0001), and an off-track lesion (OR 5.53, 95% CI 2.21–13.86, p = 0.0003). There was moderate evidence indicating that male sex (OR 1.6, 95% CI 1.07–2.37, p = 0.02) and playing contact sports (OR 1.54, 95% CI 0.96–2.45, p = 0.07) were further risk factors. Dominant side, a superior labrum from anterior to posterior (SLAP) lesion, and more than five preoperative dislocations were not found to be risk factors.

Conclusions

Patients younger than 20 years of age, a Hill–Sachs lesion, a glenoid bone lesion, shoulder hyperlaxity, and an off-track lesion appear to be significant predictors of recurrent instability following a Bankart procedure. Factors such as male sex and playing contact sports were associated with recurrent instability. Dominant side, a SLAP lesion, and more than five preoperative dislocations were not significant risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03011-w.

Validação clínica do conceito de glenoid track na instabilidade glenoumeral anterior

Objective  To evaluate the correlation of the glenoid track and glenoidal bone loss with the recurrence dislocation rate and the Rowe score.

Methods  Retrospective study that assessed the glenoid track and glenoidal bone loss through preoperative magnetic resonance imaging. Patients undergoing primary arthroscopic repair of anterior Bankart were included. Patients with glenoidal bone loss greater than 21%, rotator cuff tear, scapular waist fracture, and posterior or multidirectional instability were not included. Rowe score were the primary outcome, and the recurrence rate was the secondary outcome.

Results  One hundred and two patients were included. Postoperative recurrent instability was reported by 8 patients (7.8%). Four patients (50%) in the group with recurrence presented glenoidal bone loss greater than 13.5% against 24 (25.5%) in the group without recurrence ( p  = 0.210), with a negative predictive value of 94.6%. Three patients (37.5%) in the recurrence group were considered off-track, against 13 (13.8%) in the group without recurrence ( p  = 0.109), with a negative predictive value of 94.2%. Patients with absolute glenoid track value ≤ 1.5 mm had worse results in relation to the recurrence group, with 6 patients (75%) presenting recurrence ( p  = 0.003).

Conclusion  Off-track injury and glenoidal bone loss greater than the subcritical are not related to the recurrence rate and Rowe score, despite the high negative predictive value. The cut of the absolute value of the glenoid track at 1.5 mm had a significant relationship with the recurrence rate.

Revision Arthroscopic Bankart Repair for Anterior Shoulder Instability After a Failed Arthroscopic Soft-Tissue Repair Yields Comparable Failure Rates to Primary Bankart Repair: A Systematic Review

BACKGROUND

The management of recurrent instability after arthroscopic Bankart repair remains challenging. Of the various treatment options, arthroscopic revision repairs are of increasing interest due to improved visualization of pathology and advancements in arthroscopic techniques and instrumentation.

PURPOSE

We sought to assess the indications, techniques, outcomes, and complications for patients undergoing revision arthroscopic Bankart repair after a failed index arthroscopic soft-tissue stabilization for anterior shoulder instability.

METHODS

We performed a systematic review of studies identified by a search of Medline, Embase, and PubMed. Our search range was from data inception to April 29, 2020. Outcomes include clinical outcomes and rates of complication and revision. The Methodological Index for Non-randomized Studies (MINORS) was used to assess study quality. Data are presented descriptively.

RESULTS

Twelve studies were identified, comprising 279 patients (281 shoulders) with a mean age of 26.1 ± 3.8 years and a mean follow-up of 55.7 ± 24.3 months. Patients had improvements in postoperative outcomes (eg, pain and function). The overall complication rate was 29.5%, the most common being recurrent instability (19.9%).

CONCLUSION

With significant improvements postoperatively and comparable recurrent instability rates, there exists a potential role in the use of revision arthroscopic Bankart repair where the glenoid bone loss is less than 20%. Clinicians should consider patient history and imaging findings to determine whether a more rigorous stabilization procedure is warranted. Large prospective cohorts with long-term follow-up and improved documentation are required to determine more accurate failure rates.

Instability Severity Index Score Does Not Predict the Risk of Shoulder Dislocation after a First Episode Treated Conservatively

The first purpose of this study was to verify the association between Instability Severity Index Score (ISIS) and Recurrent Shoulder Dislocation (RSD) after a first episode treated conservatively. The second aim is to identify the risk factors associated with RSD after a primary acute shoulder anterior dislocation treated conservatively. A total of 111 patients with first traumatic anterior shoulder dislocation treated at a single trauma centre between January 2014 and March 2016 were enrolled. The main predictive variables of risk factors and the ISIS score were calculated. Among the 85 patients included, 26 cases of RSD were observed (30.6%). Considering the whole population, no significant association between ISIS and RSD were reported. Regarding other risk factors, high-risk working activities and rotator cuff injury had a significantly higher RSD risk. Sex, dominant limb, familiar history, hyperlaxity, contact or overhead sports, competitive sport, post-reduction physiokinesitherapy, return to sports activity time, Hill-Sachs lesion, bony Bankart lesion and great tuberosity fracture did not seem to influence the risk of RSD. No correlation between ISIS score and RSD in patients treated conservatively after a first episode of shoulder dislocation were reported. The only risk factors with a significant association to RSD were high-risk working activities and rotator cuff injury.

Sex-specific differences in outcomes after anterior shoulder surgical stabilization: a meta-analysis and systematic review of literature

Background

Methods

Results

Conclusion

Limites da artroscopia na instabilidade anterior do ombro

Muito se discute sobre os limites do tratamento da instabilidade anterior do ombro por artroscopia. O avanço no entendimento das repercussões biomecânicas das lesões bipolares sobre a estabilidade do ombro, bem como na identificação de fatores relacionados ao maior risco de recidiva têm nos ajudado a definir, de forma mais apurada, os limites do reparo por via artroscópica.

Ressaltamos a importância de diferenciação entre perda óssea por erosão da glenoide (POAG) e fraturas da borda da glenoide, pois o prognóstico do tratamento diverge entre essas formas de falha óssea da glenoide. Neste contexto, entendemos que há três tipos de falha óssea: a) Bankart ósseo (fratura); b) combinada; e c) POAG, e abordaremos as opções de tratamento sugerido em cada situação.

Até há pouco tempo, a escolha do método cirúrgico era norteada basicamente pelo grau de acometimento ósseo. Com a evolução do conhecimento, da biomecânica das lesões bipolares e do conceito do glenoid track (trilho da glenoide), o ponto de corte da lesão crítica, vem sendo alterado com tendência de queda. Além das falhas ou perdas ósseas, outras variáveis foram adicionadas e tornaram a decisão mais complexa, porém um pouco mais objetiva.

O presente artigo de atualização tem como objetivo fazer uma breve revisão da anatomia com as principais lesões encontradas na instabilidade; abordar detalhes importantes na técnica cirúrgica artroscópica, em especial nos casos complexos, e trazer as evidências atuais sobre os assuntos de maior divergência, buscando guiar o cirurgião na tomada de decisão.

Glenoid track measurement using magnetic resonance imaging arthrography is predictive of recurrent instability following arthroscopic shoulder stabilisation

PURPOSE

The primary aim of this study was to investigate medium-term survivorship following arthroscopic Bankart repair (ABR) for anterior glenohumeral instability. The secondary aim was to determine whether the pre-operative magnetic resonance (MR) arthrography glenoid track measurement predicted recurrent instability following ABR.

METHODS

Over a 9-year period (2008-2017), 215 patients underwent ABR. Median age was 26 years (IQR 22-32.5; range 14-77). There were 173 males (81%). 175 patients (81%) had available pre-operative MR arthrography, which was used to determine the presence of "off-track" bone loss. Retrospective analysis was undertaken to determine recurrence of instability at a median follow-up of 76 months (range 21-125 months). Survivorship analysis was undertaken using Kaplan-Meier methodology: the endpoints examined were repeat dislocation, revision stabilisation, and symptomatic instability.

RESULTS

56 patients (26%) presented with further instability, including 29 patients with recurrent dislocation and 15 patients required revision stabilisation. Cumulative incidence of instability was 10% at 1 year, 27% at 5 years and 28% at 7 years. No significant difference in instability was seen between men and women 7 years after stabilisation (19% vs 17%; p = 0.87). Age at time of surgery did not predict recurrence. "Off-track" lesions were identified in 29 patients (16.1%). The incidence of redislocation was significantly higher in these patients (24% vs 3%; p = 0.01; relative risk 7.2; 95% CI 2.45-20.5; p = 0.001). Recurrent instability without frank redislocation was also significantly higher in this group (60% vs 18%; RR 3.33, 95% CI 2.02-5.20; p < 0.0001).

CONCLUSIONS

This study has reported a significant rate of recurrent instability in longer-term follow-up after ABR. It has also identified pre-operative MR arthrography as an important predictor of recurrent instability, which may be used to risk stratify patients with anterior instability in a typical UK population.

LEVEL OF EVIDENCE

III (cohort study).

Clinical Relevance of Persistent Off-Track Hill-Sachs Lesion After Arthroscopic Latarjet Procedure

BACKGROUND

The Latarjet procedure is often used to address off-track Hill-Sachs lesions (OFF-HS) in shoulders with anterior instability. There are concerns as to whether the Latarjet procedure is able to convert all OFF-HS into on-track Hill-Sachs lesions (ON-HS) and whether this limitation could explain the cases of recurrent postoperative instability.

HYPOTHESIS

Latarjet surgery converts many preoperative OFF-HS lesions, but not all of them, and there is a difference in the failure rate between shoulders with converted lesions and those with persistent OFF-HS lesions.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients with anterior shoulder instability and an OFF-HS lesion treated with an arthroscopic classic Latarjet procedure between January 2010 and September 2017 were retrospectively evaluated. Patients with moderate or severe shoulder arthrosis, rotator cuff tears, or age older than 50 years were excluded. Glenoid track (GT), HS, HS interval (HSI), and the difference between HSI and GT (ΔHSI-GT) were measured preoperatively. A postoperative computed tomography scan and a clinical evaluation, including the Rowe and Western Ontario Shoulder Instability scores, were performed at a minimum 1- and 2-year follow-up, respectively. Postoperatively, 2 groups of patients were obtained: (1) patients with postoperative persistent OFF-HS; (2) patients with postoperative ON-HS. Clinical and imaging data were compared between the 2 groups.

RESULTS

A total of 51 patients (n = 51 shoulders), with a mean age of 29.8 ± 8.4 years (range, 15-50 years), met the inclusion criteria. Six shoulders (11.8%) still showed OFF-HS lesions despite Latarjet surgery. There were no postoperative dislocations, but 3 patients reported subluxations. The subluxation rate was significantly higher in the postoperative persistent OFF-HS group (2 [33%] vs 1 [2.2%]; P = .033). There was a wider preoperative HSI (29.8 ± 2.4 mm vs 22.9 ± 3.5 mm; P < .001) and a larger preoperative ΔHSI-GT (12.2 ± 3.8 mm vs 4.82 ± 3.2 mm; P < .001) in the persistent OFF-HS group. A receiver operating characteristic curve was performed based on preoperative ΔHSI-GT values. A preoperative ΔHSI-GT value ≥7.45 mm predicted a persistent OFF-HS after Latarjet surgery (sensitivity, 100%; specificity, 87%; positive predictive value, 50%; and negative predictive value, 100%).

CONCLUSION

Latarjet surgery converted many preoperative OFF-HS lesions into ON-HS lesions, but not all of them. Six patients (11.8%) retained an OFF-HS and had a statistically significantly higher failure rate after Latarjet surgery compared with those with postoperative ON-HS lesions. Because there were few postoperative OFF-HS lesions and few recurrences, findings are statistically fragile and should be confirmed with larger series.

Criteria-based return-to-sport testing is associated with lower recurrence rates following arthroscopic Bankart repair

HYPOTHESIS AND BACKGROUND

This study aimed to analyze the impact of a criteria-based return-to-sport (CBRTS) testing protocol on recurrent instability following arthroscopic Bankart repair. We hypothesized that patients who underwent an objective CBRTS testing protocol to guide their clearance to return to sports would have less recurrent instability than those who did not undergo testing.

METHODS

Thirty-six consecutive patients who underwent arthroscopic Bankart repair from 2016 to 2018, had a minimum of 1 year of follow-up, and completed functional and strength testing to evaluate readiness to return to sports were included in this retrospective case-control study. Patients with critical glenoid bone loss > 13.5%, multidirectional instability, and off-track Hill-Sachs lesions necessitating a remplissage or bone augmentation procedure were excluded from the study. Recurrence was defined as dislocation or subluxation symptoms requiring revision surgery. Statistical analysis included analysis of variance and the independent t test.

RESULTS

There was no difference between the study and control groups regarding age (P = .15), sex (P = .11), hand dominance (P = .56), or participation in contact sports (P = .78). Patients who underwent the CBRTS testing protocol had a reduced rate of recurrent shoulder instability (5% vs. 22%; odds ratio, 4.85; P < .001). There was no difference in the time from surgery to recurrence between the groups (12 months vs. 13.6 months, P = .43).

CONCLUSION

Athletes who underwent an objective CBRTS testing protocol to guide their clearance to return to sports had a lower rate of recurrent instability following arthroscopic Bankart repair than those cleared to return based on the time from surgery. Athletes who did not undergo CBRTS testing after arthroscopic shoulder stabilization had a 4.85 times increased likelihood of recurrent instability development after return to sports.

Imaging Modalities for the Glenoid Track in Recurrent Shoulder Instability: A Systematic Review

Background:

The glenoid track (GT) concept illustrates how the degree of glenoid bone loss and humeral bone loss in the glenohumeral joint can guide further treatment in a patient with anterior instability. The importance of determining which lesions are at risk for recurrent instability involves imaging of the glenohumeral joint, but no studies have determined which type of imaging is the most appropriate.

Purpose/Hypothesis:

The purpose of this study was to determine the validity and accuracy of different imaging modalities for measuring the GT in shoulders with recurrent anterior instability. We hypothesized that 3-dimensional computed tomography (3D-CT) would be the most accurate imaging technique.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using PubMed, Scopus, Medline, and Cochrane libraries between database inception and July 2019. We included all clinical trials or cadaveric studies that evaluated imaging modalities for assessing the GT.

Results:

A total of 13 studies were included in this review: 1 study using 2-dimensional CT, 6 studies using 3D-CT, 4 studies using magnetic resonance imaging (MRI), 1 study using magnetic resonance arthrography (MRA)/MRI, and 1 study combining CT and MRI. The mean sensitivity, specificity, and accuracy for 2D-CT was 92%, 100%, and 96%, respectively. For MRI, the means were 72.2%, 87.9%, and 84.2%, respectively. No papers included 3D-CT metrics. The mean intraclass correlation coefficients (ICCs) for intraobserver reliability were 0.9046 for 3D-CT and 0.867 for MRI. ICCs for interobserver reliability were 0.8164, 0.8845, and 0.43 for 3D-CT, MRI, and MRA/MRI, respectively.

Conclusion:

There is evidence to support the use of both CT and MRI imaging modalities in assessing the GT. In addition, few studies have compared radiographic measurements with a gold standard, and even fewer have looked at the GT concept as a predictor of outcomes. Thus, future studies are needed to further evaluate which imaging modality is the most accurate to assess the GT.

Computed Tomography-Based Preoperative Planning Provides a Pathology and Morphology-Specific Approach to Glenohumeral Instability With Bone Loss

PURPOSE

To use computed tomography (CT) to determine a reproducible method of coracoid measurement to compare the ability of the classic Latarjet technique and the congruent arc modification (CAM) to restore native glenoid diameter and to develop a preoperative planning algorithm for glenoid restoration with a goal of achieving an on-track shoulder.

METHODS

Coracoid dimensions were measured on multiplanar reconstructed shoulder CT scans of patients aged 18 to 45 years obtained between December 1, 2019, and March 13, 2020. Patients were excluded if CT demonstrated osteophyte formation, glenoid dysplasia, coracoid fracture, or tumor. The proportion of glenoid diameter able to be restored using classic Latarjet technique and CAM were calculated. A treatment algorithm was proposed considering the amount of bone loss present and coracoid dimensions.

RESULTS

Coracoid dimensions of 117 consecutive patients were measured and varied considerably (length: 17.5-31.8 mm, width: 9.1-20.5 mm, thickness: 6.1-15.7 mm). While most patients had harvestable coracoid length ≥20 mm (male: 96.3% vs female: 94.4%, P = .65), only 27.8% of female patients had coracoid thickness ≥10 mm. When comparing Latarjet techniques, there was no difference in the proportion of patients in whom 30% glenoid diameter could be fully restored, but CAM was able to restore at least 35% in more male and female patients (98.8% vs 79.0% and 100% vs 61.1%, respectively, P = .00001). Intra- and inter-rater reliability was excellent ( intraclass correlation coefficient ≥0.950 for all dimensions).

CONCLUSIONS

We describe a reliable method of measuring coracoid dimensions for preoperative planning of glenoid restoration. The classic Latarjet technique reliably restores the glenoid anteroposterior diameter with bone loss of up to 30%. The majority of female patients have coracoid thickness <10 mm, which may increase the risk of graft fracture when using CAM. The decision to use the classic Latarjet technique or CAM considers each individual's glenoid and coracoid dimensions with a goal of achieving an on-track shoulder.

CLINICAL RELEVANCE

Our reliable method of coracoid measurement demonstrated the differing abilities of the classic Latarjet and CAM to restore the native glenoid diameter. An evidence-based algorithm using these measurements was developed to assist in preoperative planning for glenohumeral instability in the setting of bone loss, with a goal of achieving an on-track shoulder. Alternative techniques may be considered if an on-track shoulder cannot be achieved with Latarjet.

Evolving Concepts in the Management of Shoulder Instability

BACKGROUND

Shoulder instability exists on a spectrum ranging from subtle subluxation and pain to dislocation and can be the result of a traumatic event or repetitive microtrauma. Shoulder instability can result in significant disability and often requires surgical intervention, especially amongst younger, active patient populations. The optimal treatment of shoulder instability depends on the degree of instability and concomitant pathology involving the labrum, capsule, and bony anatomy of the glenoid and humeral head. Even with surgical intervention, recurrent instability remains a relatively common and difficult problem to address.

PURPOSE

With a focus on anterior instability, the purpose of this review article is to discuss the current assessment and treatment of shoulder instability, and highlight current and future treatment modalities, as well as to identify current trends and deficiencies in our current management. We also provide an algorithm for the surgical treatment of anterior shoulder instability.

METHODS

Literature databases were extensively searched for recent articles related to the mechanism, diagnosis, and treatment of shoulder instability to comprise a comprehensive review.

CONCLUSION

Although there are multiple treatment modalities available for shoulder instability, such as nonoperative management, open and arthroscopic Bankart repair, Latarjet procedures, and remplissage, orthopaedic surgeons continue to learn about the most appropriate method of management as increasing long-term outcomes become available.

Epidemiology of shoulder instability in Italy: A 14-years nationwide registry study

INTRODUCTION

The aim of this study is to estimate the annual number of shoulder dislocation hospitalizations in Italy from 2001 to 2014, to explore geographical variation in access to hospitalizations between the 3 macro-regions of Italy (North, Centre and South) and to perform statistical projections of hospitalizations volumes and rates based on data from 2001 to 2014.

MATERIALS AND METHODS

Data of the Italian Ministry of Health regarding the National Hospital Discharge records (SDO) were analysed for the period of the survey (2001-2014). These data are anonymous and include the patient's age, sex, domicile, region of hospitalization, length of the hospitalization, and type of reimbursement (public or private).

RESULTS

During the 14-year study period, 92,784 hospitalizations to treat shoulder dislocation were performed in Italy, which represented an incidence of 11.2 hospitalizations for every 100,000 Italian inhabitants. 56,514 patients underwent hospitalization for non-surgical treatment. 36,270 patients underwent hospitalization for surgical treatment. The higher hospitalizations rate was among males from 15 to 64 years of age.

CONCLUSIONS

Increasing rates of surgical hospitalization and decreasing rates of hospitalization for non-surgical treatment of shoulder dislocation are observed over a 14-year period. This study confirms that the socioeconomic burden of shoulder dislocation surgery heavily affects the working population. Most shoulder instability procedures were performed on males. The present study provides a description of the frequency and national distribution of shoulder instability in Italy. This study shows an increase in surgical procedures for shoulder instability in Italy.

Does an "Off-Track" Hill-Sachs Lesion That Is Misclassified as "Non-Engaging" Affect Outcomes From Bankart Repair Alone Compared With Bankart Repair Combined With Remplissage?

PURPOSE

To determine how intraoperative assessment (engagement test) may affect recurrent dislocation rate and to compare the clinical outcomes, recurrence rates, and presence of on-/off-track conditions between cases that received arthroscopic Bankart repair alone (nonengaged Hill-Sachs lesion) and Bankart repair with remplissage (engaged Hill-Sachs lesion).

METHODS

We retrospectively reviewed 213 patients who underwent arthroscopic Bankart repair alone (186 patients with nonengaging lesions, group A) or with remplissage (27 patients with engaging lesion, group B) for recurrent anterior shoulder instability with <25% glenoid bone defect. The presence of an engaging Hill-Sachs lesion was determined during arthroscopic evaluation. On-track or off-track lesions were assessed retrospectively from preoperative 3-dimensional (3D) computed tomography (CT).

RESULTS

Mean glenoid bone defect was 13.7% in group A and 20.7% in group B (P < .001). Off-track lesions were identified in 8.1% (15/186) and 100% (27/27) in group B. At the final follow-up (minimum 2 years; mean follow-up periods after surgery of 50.1 months in group A and 47.7 months in group B), there were no significant differences in shoulder functional scores and recurrence rates between groups, despite improvement after surgery. In the off-track lesion (group A-1: nonengaging but off-track lesion), recurrence instability occurred in 9 patients (60%, 9/15). Also, comparing group A-1 and group B, we noted significant differences in shoulder functional scores and recurrence rates (P < .001).

CONCLUSION

Of 186 patients, 8.1% with nonengaging Hill-Sachs lesions during direct arthroscopic examination under anesthesia actually demonstrated off-track lesions on preoperative 3D CT scans retrospectively, with 60% experiencing recurrent instability. Intraoperative manual assessment for Hill-Sachs engagement was inferior to 3D CT scan in establishing the presence of off-track defects.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Anterior glenohumeral instability: Current review with technical pearls and pitfalls of arthroscopic soft-tissue stabilization

The glenohumeral joint (GHJ) allows for a wide range of motion, but is also particularly vulnerable to episodes of instability. Anterior GHJ instability is especially frequent among young, athletic populations during contact sporting events. Many first time dislocators can be managed non-operatively with a period of immobilization and rehabilitation, however certain patient populations are at higher risk for recurrent instability and may require surgical intervention for adequate stabilization. Determination of the optimal treatment strategy should be made on a case-by-case basis while weighing both patient specific factors and injury patterns (i.e., bone loss). The purpose of this review is to describe the relevant anatomical stabilizers of the GHJ, risk factors for recurrent instability including bony lesions, indications for arthroscopic vs open surgical management, clinical history and physical examination techniques, imaging modalities, and pearls/pitfalls of arthroscopic soft-tissue stabilization for anterior glenohumeral instability.

Cuistow: Chinese Unique Inlay Bristow: A Novel Arthroscopic Surgical Procedure for Treatment of Recurrent Anterior Shoulder Instability with a Minimum 3-Year Follow-Up

BACKGROUND

The prevalence of nonunion after the Latarjet procedure remains high. The purpose of the present study was to investigate healing and clinical outcomes after a novel arthroscopic coracoid process transfer procedure.

METHODS

Sixty-three patients who underwent the arthroscopic inlay Bristow procedure combined with Bankart repair were identified, and 51 patients who met the inclusion criteria were enrolled in this study. The key feature of this technique was that the coracoid process was trimmed and fixed into a trough (5 to 10 mm deep) in the glenoid neck with a metal screw. Bone graft union and positioning accuracy were assessed with use of postoperative computed tomography (CT) imaging. Clinical examinations, return to sport, and functional scores (American Shoulder and Elbow Surgeons [ASES] and Rowe scores) were recorded.

RESULTS

The mean duration of follow-up (and standard deviation) was 41.5 ± 7.7 months (range, 36 to 48 months). Postoperative CT scans showed that the position of coracoid graft was at 4:10 (from 3:50 to 5:00) (referencing the right shoulder) in the sagittal view. The α angle was 16.4° ± 9.5°, with 4 (7.8%) of 51 screws being over-angulated (α > 25°). On the axial view, the graft position was considered to be flush in 33 patients (64.7%), medial in 11 (21.6%), congruent in 7 (13.7%), and lateral or too medial in none. At 1 year, the coracoid graft had healed in 49 patients (96.1%) and had failed to unite in 2 patients. CT scanning, performed for 47 patients, showed grade-0 osteolysis in 9 patients, grade-1 osteolysis in 21 patients, and grade-2 osteolysis in 17 patients. At the time of the latest follow-up, there was a significant increase in the Rowe score (from 35.5 ± 8.3 to 95.7 ± 7.2) and the ASES score (from 71.2 ± 9.7 to 91.5 ± 4.4), and 87.0% of patients were able to return to sport. No arthropathy was observed in any patient.

CONCLUSIONS

After a minimum 3-year follow-up, the arthroscopic inlay Bristow procedure resulted in a high rate of graft healing, excellent clinical outcomes, and a high rate of return to sports.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Hill-Sachs interval to glenoid track width ratio is comparable to the instability severity index score for predicting risk of recurrent instability after arthroscopic Bankart repair

PURPOSE

The purpose of this study was to clinically validate the Hill-Sachs interval to glenoid track width ratio (H/G ratio) compared with the instability severity index (ISI) score for predicting an increased risk of recurrent instability after arthroscopic Bankart repair.

METHODS

A retrospective evaluation was performed using data from patients with anteroinferior shoulder instability who underwent arthroscopic Bankart repair with a follow-up period of at least 24 months. A receiver operating characteristic (ROC) curve was used to determine the optimal cut-off values for the H/G ratio and the ISI score to predict an increased risk of recurrent instability. The area under the ROC curve (AUC) of the two methods and the sensitivity and specificity of their optimal cut-off values were compared.

RESULTS

A total of 222 patients were included, among whom 31 (14.0%) experienced recurrent instability during the follow-up period. The optimal cut-off values for predicting an increased risk of recurrent instability were an H/G ratio of ≥ 0.7 and ISI score of ≥ 4. There were no significant differences between the AUC of the two methods (H/G ratio AUC = 0.821, standard error = 0.035 and ISI score AUC = 0.792, standard error = 0.04; n.s.) nor between the sensitivity and specificity of the optimal cut-off values (n.s. and n.s., respectively).

CONCLUSIONS

The H/G ratio is comparable to the ISI score for predicting an increased risk of recurrent instability after arthroscopic Bankart repair. Surgeons are recommended to consider other strategies to treat anterior shoulder instability if H/G ratio is ≥ 0.7.

LEVEL OF EVIDENCE

III.

Determining On-/Off-track Lesions in Glenohumeral Dislocation Using Multiplanar Reconstruction Computed Tomography Is Easier and More Reproducible Than Using 3-dimensional Computed Tomography

BACKGROUND

The glenoid track is a useful tool to predict engagement and therefore the risk of recurrence of dislocation in the presence of Hill-Sachs and/or bony Bankart lesions. To assess the glenoid track preoperatively, only methods using 3-dimensional reconstruction (3DR) have been described, but these lack a standardized, reliable, and easy description.

PURPOSE/HYPOTHESIS

The purpose was to evaluate a new method for determining the glenoid track using computed tomography (CT) scan with multiplanar reconstruction (MPR) in comparison with using 3DR images. Our hypothesis was that the MPR method would be easier to standardize and more reproducible.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

A total of 52 patients whose arthro-CT scan revealed a Hill-Sachs lesion, whether in combination with a bony Bankart lesion or not, were included. Digital Imaging and Communications in Medicine data from the 52 CT scans were all analyzed using open source image analysis software. Glenoid width, with or without associated bony defect, and the Hill-Sachs interval (HSI) were measured on MPR as well as on 3DR images. All measurements obtained using both methods were directly compared and evaluated for intra- and interobserver reliability.

RESULTS

In absolute values, only small differences were seen between the MPR and 3DR methods, amounting to a maximal difference of 0.07 cm for the HSI and 0.04 cm for the glenoid width. For glenoid measurements, both methods were similar. For humeral measurements, the MPR method demonstrated higher inter- and intraobserver reliability than did the 3DR method.

CONCLUSION

The newly described MPR method for the assessment of the glenoid track and HSI is at least as accurate as the published 3DR method, with better intra- and interobserver reliability. Because MPRs are also easier to obtain, this method could be recommended in daily practice.

First-time Glenohumeral Dislocations: Current Evidence and Considerations in Clinical Decision Making

The decision to manage first-time shoulder dislocations conservatively or operatively has become increasingly complex because of conflicting literature. Although shoulder dislocations have traditionally been managed with reduction and immobilization, recent evidence has suggested high rates of subsequent recurrence. Surgical intervention is thought to better restore stability and decrease recurrence rates; however, it also has the potential for additional morbidity and financial cost. As such, recent literature has sought to better define patient risk profiles to identify optimal candidates for both conservative and operative management. The purpose of the current review is to provide a comprehensive and evidence-based assessment of the most recent literature to better delineate an appropriate treatment algorithm for this challenging clinical scenario.

Accuracy of Currently Available Methods in Quantifying Anterior Glenoid Bone Loss: Controversy Regarding Gold Standard-A Systematic Review

PURPOSE

To determine the accuracy of glenoid bone loss-measuring methods and assess the influence of the imaging modality on the accuracy of the measurement methods.

METHODS

A literature search was performed in the PubMed (MEDLINE), Embase, and Cochrane databases from 1994 to June 11, 2019. The guidelines and algorithm of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) were used. Included for analysis were articles reporting the accuracy of glenoid bone loss-measuring methods in patients with anterior shoulder instability by comparing an index test and a reference test. Furthermore, articles were included if anterior glenoid bone loss was quantified using a ruler during arthroscopy or by measurements on plain radiograph(s), computed tomography (CT) images, or magnetic resonance images in living humans. The risk of bias was determined using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.

RESULTS

Twenty-one studies were included, showing 17 different methods. Three studies reported on the accuracy of methods performed on 3-dimensional CT. Two studies determined the accuracy of glenoid bone loss-measuring methods performed on radiography by comparing them with methods performed on 3-dimensional CT. Six studies determined the accuracy of methods performed using imaging modalities with an arthroscopic method as the reference. Eight studies reported on the influence of the imaging modality on the accuracy of the methods. There was no consensus regarding the gold standard. Because of the heterogeneity of the data, a quantitative analysis was not feasible.

CONCLUSIONS

Consensus regarding the gold standard in measuring glenoid bone loss is lacking. The use of heterogeneous data and varying methods contributes to differences in the gold standard, and accuracy therefore cannot be determined.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II, III, and IV studies.

Posterior shoulder instability: a systematic review

INTRODUCTION

This review aims to provide information on outcomes of surgical procedures for soft tissue or bony glenoid and/or humeral abnormalities in case of posterior shoulder instability.

SOURCE OF DATA

A systematic review of the literature according to the PRISMA guidelines was performed. A comprehensive search of PubMed, Medline, CINAHL, Cochrane, Embase, Ovid and Google Scholar databases using various combinations of the keywords 'shoulder', 'posterior instability', 'dislocation', 'reversed bony bankart', 'reversed Hill Sachs', and 'capsulolabral' was performed.

AREAS OF AGREEMENT

A total of 847 shoulders in 810 patients were included. A redislocation event occurred in 33 (8.7%) of 411 shoulders with soft tissue abnormalities and in 12 (9.1%) of 132 shoulders with bony abnormalities of the glenoid, humeral head or both.

AREAS OF CONTROVERSY

The optimal treatment modalities for posterior shoulder dislocation remain to be defined.

GROWING POINTS

Operative stabilization for posterior shoulder instability should be lesion-specific and should correct all components of the posterior instability.

AREAS TIMELY FOR DEVELOPING RESEARCH

Future prospective studies should aim to establish the optimal treatment modalities for posterior shoulder instability.