Analysis of risk factors for glenoid bone defect in anterior shoulder instability

Tomographic evaluation of Hill-Sachs lesions: is there a correlation between different methods of measurement?

BACKGROUND

Several methods are currently available to evaluate and quantify the glenoid or humeral bone loss; however, none is universally accepted, particularly in the case of Hill-Sachs (HS) lesions.

PURPOSE

To establish whether there is correlation among different methods of measuring HS lesions, and to investigate the correlation between glenoid bone loss and the various HS lesion measurements and to assess the inter-observer reliability of such measurements.

MATERIAL AND METHODS

We assessed computed tomography (CT) or arthro-CT scans taken from individuals with recurrent anterior glenohumeral dislocation. The scans were independently assessed by two examiners. The parameters assessed were as follows: HS lesion width and depth on the axial and coronal planes, articular arc loss on the axial plane, and percentage of glenoid bone loss on the sagittal plane.

RESULTS

Scans from 50 shoulders were assessed. The percentage of articular arc loss and HS lesion width on the axial plane were the only measurements that exhibited strong correlation (r = 0.83; P < 0.001). The values of the correlation coefficient corresponding to HS lesion depth on the coronal plane were the lowest. Most of the measurements exhibited moderate correlation. The inter-examiner reliability was good relative to all measurements except for HS lesion width and depth on the coronal plane, for which it was moderate.

CONCLUSION

The measurements of articular arc loss and HS lesion width on the axial plane exhibited strong correlation. The inter-examiner reliability relative to articular arc loss, HS lesion width and depth on the axial plane, and glenoid bone loss was good.

Glenoid Bone Loss in Traumatic Glenohumeral Instability in the Adolescent Population

BACKGROUND

Glenoid bone loss can affect the outcome and treatment for posttraumatic recurrent anterior glenohumeral instability. Clinical presentation in the adolescent age group with shoulder instability and glenoid bone loss is largely unknown. On the basis of this information, we believe there will be a high incidence of glenoid bone loss in adolescent patients with recurrent glenohumeral instability. We hypothesize that high-impact injuries, sports injuries, and reductions requiring sedation will be factors associated with glenoid bone loss.

METHODS

We performed a retrospective cross-sectional cohort study reviewing consecutive adolescent patients (n=114) with recurrent traumatic glenohumeral instability between 2004 and 2012. Chart analysis included demographic, presenting, and radiographic data. Glenoid bone loss was interpreted from plain radiographs, computed tomography (2D and/or 3D), magnetic resonance imaging, and/or arthroscopy. We compared possible risk factors between subjects with and without glenoid bone defects using the χ test or 2 sample t tests.

RESULTS

Glenoid bone loss was seen in 55 patients (48.2%) with 15 of these patients (27%) having critical bone loss. Forty-five percent of appreciated glenoid bone loss was not visualized on plain radiographs. The average age was 15.1 years (range, 6.5 to 18.1) with male to female ratio 3.7:1. Male sex, older age, and taller stature were all statistically associated with glenoid bone loss (P=0.02, 0.01, and 0.02, respectively). Primary dislocations that occurred during sports were more likely to have glenoid bone loss (55.9% vs. 78.2%, P=0.01). The presence of an apprehension sign on physical examination was positively correlated with bone loss (P=0.008).

CONCLUSIONS

The presence of glenoid bone loss in primary traumatic glenohumeral instability in the adolescent population is high, however, not as high as previously reported. Factors associated with glenoid bone loss include male sex, older age, taller stature, sports injuries, and the presence of apprehension on physical examination.

LEVEL OF EVIDENCE

This study establishes patients who may be at high risk for glenoid bone loss based on mechanism of injury and physical examination findings. This prognostic study is a level II retrospective study.

Clinical Validation of the Glenoid Track Concept in Anterior Glenohumeral Instability

BACKGROUND

Glenoid and humeral bone loss are well-described risk factors for failure of arthroscopic shoulder stabilization. Recently, consideration of the interactions of these types of bone loss (bipolar bone loss) has been used to determine if a lesion is "on-track" or "off-track." The purpose of this study was to study the relationship of the glenoid track to the outcomes of arthroscopic Bankart reconstructions.

METHODS

Over a 2-year period, 57 shoulders that were treated with an isolated, primary arthroscopic Bankart reconstruction performed at a single facility were included in this study. The mean patient age was 25.5 years (range, 20 to 42 years) at the time of the surgical procedure, and the mean follow-up was 48.3 months (range, 23 to 58 months). Preoperative magnetic resonance imaging was used to determine glenoid bone loss and Hill-Sachs lesion size and location and to measure the glenoid track to classify the shoulders as on-track or off-track. Outcomes were assessed according to shoulder stability on examination and subjective outcome.

RESULTS

There were 10 recurrences (18%). Of the 49 on-track patients, 4 (8%) had treatment that failed compared with 6 (75%) of 8 off-track patients (p = 0.0001). Six (60%) of 10 patients with recurrence of instability were off-track compared with 2 (4%) of 47 patients in the stable group (p = 0.0001). The positive predictive value of an off-track measurement was 75% compared with 44% for the predictive value of glenoid bone loss of >20%.

CONCLUSIONS

The application of the glenoid track concept to our cohort was superior to using glenoid bone loss alone with regard to predicting postoperative stability. This method of assessment is encouraged as a routine part of the preoperative evaluation of all patients under consideration for arthroscopic anterior stabilization.

LEVEL OF EVIDENCE

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

A Clinical Review of Return-to-Play Considerations After Anterior Shoulder Dislocation

Context:

Shoulder dislocations are common in contact sports, yet guidelines regarding the best treatment strategy and time to return to play have not been clearly defined.

Evidence Acquisition:

Electronic databases, including PubMed, MEDLINE, and Embase, were reviewed for the years 1980 through 2015.

Study Design:

Clinical review.

Level of Evidence:

Level 4.

Results:

Much has been published about return to play after anterior shoulder dislocation, but almost all is derived from expert opinion and clinical experience rather than from well-designed studies. Recommendations vary and differ depending on age, sex, type of sport, position of the athlete, time in the sport’s season, and associated pathology. Despite a lack of consensus and specific recommendations, there is agreement that before being allowed to return to sport, athletes should be pain free and demonstrate symmetric shoulder and bilateral scapular strength, with functional range of motion that allows sport-specific participation. Return to play usually occurs 2 to 3 weeks from the time of injury. Athletes with in-season shoulder instability returning to sport have demonstrated recurrence rates ranging from 37% to 90%. Increased bone loss, recurrent instability, and injury occurring near the end of season are all indications that may push surgeons and athletes toward earlier surgical intervention.

Conclusion:

Most athletes are able to return to play within 2 to 3 weeks but there is a high risk of recurrent instability.

Bankart repair versus Bankart repair plus remplissage: an in vitro biomechanical comparative study

PURPOSE

To biomechanically compare Bankart lesion repair alone and Bankart lesion repair associated with infraspinatus capsulotenodesis described as «remplissage», in the treatment of combined Bankart and Hill-Sachs lesions.

METHODS

Seven pairs (right and left) of cadaveric shoulders have been tested, first without any lesion and then after performing a combined Bankart and Hill-Sachs lesions. For each pair, the specimens were then randomly assigned for Bankart lesion repair alone on one side or for Bankart lesion repair associated with remplissage on the other side. During tests, the shoulder was placed at 90° of abduction and at maximal external rotation, which value was recorded. A 50 N postero-anterior load was then applied to the proximal humerus, and the stiffness was calculated from the obtained load-displacement curve.

RESULTS

Bankart and Hill-Sachs lesions significantly (p < 0.05) decreased joint stiffness compared with intact joint. Bankart lesion repair alone did not restore stiffness to the level of intact, while adding the remplissage to the Bankart lesion repair did. External rotation was significantly increased after creation of the Bankart and Hill-Sachs lesion; Bankart repair restored the external rotation to the level of intact, while Bankart lesion repair associated with remplissage significantly decreased external rotation compared with intact and to Bankart lesion repair alone.

CONCLUSION

In cadaveric shoulders with combined Bankart and Hill-Sachs lesions, Bankart lesion repair associated with remplissage restored intact joint stiffness contrary to Bankart lesion repair alone. This increase in stiffness was associated with a decrease in external rotation.

Relationship Between Glenoid Defects and Hill-Sachs Lesions in Shoulders With Traumatic Anterior Instability

BACKGROUND

While the combination of a glenoid defect and a Hill-Sachs lesion in a shoulder with anterior instability has recently been termed a bipolar lesion, their relationship is unclear.

PURPOSE

To investigate the relationship of the glenoid defect and Hill-Sachs lesion and the factors that influence the occurrence of these lesions as well as the recurrence of instability.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

The prevalence and size of both lesions were evaluated retrospectively by computed tomography scanning in 153 shoulders before arthroscopic Bankart repair. First, the relationship of lesion prevalence and size was investigated. Then, factors influencing the occurrence of bipolar lesions were assessed. Finally, the influence of these lesions on recurrence of instability was investigated in 103 shoulders followed for a minimum of 2 years.

RESULTS

Bipolar lesions, isolated glenoid defects/isolated Hill-Sachs lesions, and no lesion were detected in 86, 45, and 22 shoulders (56.2%, 29.4%, and 14.4%), respectively. As the glenoid defect became larger, the Hill-Sachs lesion also increased in size. However, the size of these lesions showed a weak correlation, and large Hill-Sachs lesions did not always coexist with large glenoid defects. The prevalence of bipolar lesions was 33.3% in shoulders with primary instability and 61.8% in shoulders with recurrent instability. In relation to the total events of dislocations/subluxations, the prevalence was 44.2% in shoulders with 1 to 5 events, 69.0% in shoulders with 6 to 10 events, and 82.8% in shoulders with ≥11 events. Regarding the type of sport, the prevalence was 58.9% in athletes playing collision sports, 53.3% in athletes playing contact sports, and 29.4% in athletes playing overhead sports. Postoperative recurrence of instability was 0% in shoulders without lesions, 0% with isolated Hill-Sachs lesions, 8.3% with isolated glenoid defects, and 29.4% with bipolar lesions. The presence of a bipolar lesion significantly influenced the recurrence rate, but lesion size did not.

CONCLUSION

The prevalence of bipolar lesions was approximately 60%. As glenoid defects became larger, Hill-Sachs lesions also enlarged, but there was no strong correlation. Bipolar lesions were frequent in patients with recurrent instability, patients with repetitive dislocation/subluxation, and those playing collision/contact sports. Instability showed a high recurrence rate in shoulders with bipolar lesions.

Imaging methods for quantifying glenoid and Hill-Sachs bone loss in traumatic instability of the shoulder: a scoping review

Background

Glenohumeral instability is a common problem following traumatic anterior shoulder dislocation. Two major risk factors of recurrent instability are glenoid and Hill-Sachs bone loss. Higher failure rates of arthroscopic Bankart repairs are associated with larger degrees of bone loss; therefore it is important to accurately and reliably quantify glenohumeral bone loss pre-operatively. This may be done with radiography, CT, or MRI; however no gold standard modality or method has been determined. A scoping review of the literature was performed to identify imaging methods for quantifying glenohumeral bone loss.

Methods

The scoping review was systematic in approach using a comprehensive search strategy and standardized study selection and evaluation. MEDLINE, EMBASE, Scopus, and Web of Science were searched. Initial selection included articles from January 2000 until July 2013, and was based on the review of titles and abstracts. Articles were carried forward if either reviewer thought that the study was appropriate. Final study selection was based on full text review based on pre-specified criteria. Consensus was reached for final article inclusion through discussion amongst the investigators. One reviewer extracted data while a second reviewer independently assessed data extraction for discrepancies.

Results

Forty-one studies evaluating glenoid and/or Hill-Sachs bone loss were included: 32 studies evaluated glenoid bone loss while 11 studies evaluated humeral head bone loss. Radiography was useful as a screening tool but not to quantify glenoid bone loss. CT was most accurate but necessitates radiation exposure. The Pico Method and Glenoid Index method were the most accurate and reliable methods for quantifying glenoid bone loss, particularly when using three-dimensional CT (3DCT). Radiography and CT have been used to quantify Hill-Sachs bone loss, but have not been studied as extensively as glenoid bone loss.

Conclusions

Radiography can be used for screening patients for significant glenoid bone loss. CT imaging, using the Glenoid Index or Pico Method, has good evidence for accurate quantification of glenoid bone loss. There is limited evidence to guide imaging of Hill-Sachs bone loss. As a consensus has not been reached, further study will help to clarify the best imaging modality and method for quantifying glenohumeral bone loss.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-015-0607-1) contains supplementary material, which is available to authorized users.

Redefining "Critical" Bone Loss in Shoulder Instability: Functional Outcomes Worsen With "Subcritical" Bone Loss

BACKGROUND

Glenoid bone loss is a common finding in association with anterior shoulder instability. This loss has been identified as a predictor of failure after operative stabilization procedures. Historically, 20% to 25% has been accepted as the "critical" cutoff where glenoid bone loss should be addressed in a primary procedure. Few data are available, however, on lesser, "subcritical" amounts of bone loss (below the 20%-25% range) on functional outcomes and failure rates after primary arthroscopic stabilization for shoulder instability.

PURPOSE

To evaluate the effect of glenoid bone loss, especially in subcritical bone loss (below the 20%-25% range), on outcomes assessments and redislocation rates after an isolated arthroscopic Bankart repair for anterior shoulder instability.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Subjects were 72 consecutive anterior instability patients (73 shoulders) who underwent isolated anterior arthroscopic labral repair at a single military institution by 1 of 3 sports medicine fellowship-trained orthopaedic surgeons. Data were collected on demographics, the Western Ontario Shoulder Instability (WOSI) score, Single Assessment Numeric Evaluation (SANE) score, and failure rates. Failure was defined as recurrent dislocation. Glenoid bone loss was calculated via a standardized technique on preoperative imaging. The average bone loss across the group was calculated, and patients were divided into quartiles based on the percentage of glenoid bone loss. Outcomes were analyzed for the entire cohort, between the quartiles, and within each quartile. Outcomes were then further stratified between those sustaining a recurrence versus those who remained stable.

RESULTS

The mean age at surgery was 26.3 years (range, 20-42 years), and the mean follow-up was 48.3 months (range, 23-58 months). The cohort was divided into quartiles based on bone loss. Quartile 1 (n = 18) had a mean bone loss of 2.8% (range, 0%-7.1%), quartile 2 (n = 19) had 10.4% (range, 7.3%-13.5%), quartile 3 (n = 18) had 16.1% (range, 13.5%-19.8%), and quartile 4 (n = 18) had 24.5% (range, 20.0%-35.5%). The overall mean WOSI score was 756.8 (range, 0-2097). The mean WOSI score correlated with SANE scores and worsened as bone loss increased in each quartile. There were significant differences (P < .05) between quartile 1 (mean WOSI/SANE, 383.3/62.1) and quartile 2 (mean, 594.0/65.2), between quartile 2 and quartile 3 (mean, 839.5/52.0), and between quartile 3 and quartile 4 (mean, 1187.6/46.1). Additionally, between quartiles 2 and 3 (bone loss, 13.5%), the WOSI score increased to rates consistent with a poor clinical outcome. There was an overall failure rate of 12.3%. The percentage of glenoid bone loss was significantly higher among those repairs that failed versus those that remained stable (24.7% vs 12.8%, P < .01). There was no significant difference in failure rate between quartiles 1, 2, and 3, but there was a significant increase in failure (P < .05) between quartiles 1, 2, and 3 (7.3%) when compared with quartile 4 (27.8%). Notably, even when only those patients who did not sustain a recurrent dislocation were compared, bone loss was predictive of outcome as assessed by the WOSI score, with each quartile's increasing bone loss predictive of a worse functional outcome.

CONCLUSION

While critical bone loss has yet to be defined for arthroscopic Bankart reconstruction, our data indicate that "critical" bone loss should be lower than the 20% to 25% threshold often cited. In our population with a high level of mandatory activity, bone loss above 13.5% led to a clinically significant decrease in WOSI scores consistent with an unacceptable outcome, even in patients who did not sustain a recurrence of their instability.

Bone fragment union and remodeling after arthroscopic bony bankart repair for traumatic anterior shoulder instability with a glenoid defect: influence on postoperative recurrence of instability

BACKGROUND

Although good clinical outcomes have been reported after arthroscopic bony Bankart repair, the extent of bone union is still unclear.

PURPOSE

To investigate bone union after arthroscopic bony Bankart repair and its influence on postoperative recurrence of instability.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Among 113 consecutive shoulders that underwent arthroscopic bony Bankart repair, postoperative evaluation of bone union by computed tomography (CT) was performed at various times in 81 shoulders. Bone union was investigated during 3 periods: 3 to 6 months postoperatively (first period), 7 to 12 months postoperatively (second period), and 13 months or more postoperatively (third period). The influence of the size of the preoperative glenoid defect and the size of the bone fragment on bone union was investigated, as well as the influence of bone union on postoperative recurrence of instability. In shoulders with bone union, bone fragment remodeling and changes in the glenoid defect size were also investigated.

RESULTS

The bone union rate was 30.5% in the first period, 55.3% in the second period, and 84.6% in the third period. Among 53 shoulders with CT evaluation in the second period or later and follow-up for a minimum of 1 year, there was complete union in 33 shoulders (62.3%), partial union in 3 (5.7%), nonunion in 8 (15.1%), and no fragment on CT in 9 (17.0%). The complete union rate was 50% for 22 shoulders with small bone fragments (<5% of the glenoid diameter), 56.3% for 16 shoulders with medium fragments (5%-10%), and 86.7% for 15 shoulders with large fragments (>10%). The recurrence rate for postoperative instability was only 6.1% for shoulders with complete union, while it was 50% for shoulders with partial union, nonunion, no fragment, and no fragment on CT. The recurrence rate was significantly higher (36.4%) in shoulders with small fragments, but it was significantly lower in shoulders with bone union. In shoulders with bone union, the bone fragment frequently became larger over time, while the size of the glenoid defect decreased significantly from 18.6% preoperatively to 4.7% postoperatively.

CONCLUSION

Bone union was not always achieved after arthroscopic bony Bankart repair, and union was often delayed. Recurrence of instability was significantly more frequent when bone union failed. The size of the glenoid defect decreased significantly in shoulders with bone union.

Increasing preoperative dislocations and total time of dislocation affect surgical management of anterior shoulder instability

Purpose:

Our purpose was to determine the relationship between number of preoperative shoulder dislocations and total dislocation time and the need to perform bone deficiency procedures at the time of primary anterior instability surgery. Our hypothesis was that need for bone deficiency procedures would increase with the total number and hours of dislocation.

Materials and Methods:

A retrospective review was performed of primary instability surgeries performed by a single surgeon. Patients with <25% glenoid bone loss were treated with an isolated arthroscopic Bankart repair. Those who also had an engaging Hill-Sachs lesion underwent arthroscopic Bankart repair with remplissage. Patients with >25% glenoid bone loss were treated with Latarjet reconstruction. Number of dislocations and total dislocation time were examined for their relationship with the treatment method.

Results:

Ten arthroscopic Bankart repairs, 13 arthroscopic Bankart plus remplissage procedures, and 9 Latarjet reconstructions were available for review. Total dislocations (P = 0.012) and total hours of dislocation (P = 0.019) increased from the Bankart, to the remplissage, to the Latarjet groups. Patients with a total dislocation time of 5 h or more were more likely to require a Latarjet reconstruction (P = 0.039). Patients with only 1 preoperative dislocation were treated with an isolated Bankart repair in 64% (7 of 11) of cases, whereas those with 2 or more dislocations required a bone loss procedure in 86% (18 of 21) of cases (P = 0.013).

Conclusion:

Increasing number of dislocations and total dislocation time are associated with the development of glenoid and humeral head bony lesions that alter surgical management of anterior shoulder instability. The necessity for the addition of a remplissage to an arthroscopic Bankart repair or the use of a Latarjet reconstruction increases with only 1 recurrent dislocation.

Level of evidence:

Level III, retrospective comparative study.

Glenoid labrum pathology

The glenoid labrum is the fibrocartilage of the shoulder joint, anchoring the joint capsule and shoulder ligaments. Morphology varies regionally, especially in the superior and anterior region; these variants can sometimes be confused with pathological aspects. The labrum is often involved in shoulder pathology, by single trauma or, more often, repeated microtrauma. It seems logical to classify and to describe tears according to two criteria: the sector involved, and associated pain or instability. In the superior labrum, SLAP lesions are the most frequent. These combine labral lesion and lesion of the proximal insertion of the long head of the biceps brachii tendon. The most frequent form is SLAP II. They may be associated with instability or not. In the antero-inferior and postero-inferior labrum, lesions are mainly due to instability, particularly Bankart lesions (capsulolabral avulsion) anteriorly and Kim's lesion posteriorly. Circumferential labral lesions may be found in unstable shoulder. Finally, postero-superior lesions involve Walch's internal impingement: repeated contact between the deep surface of the cuff and the labrum, which takes on a degenerative aspect, with a kissing lesion of the cuff. There is no general rule for management: some labral lesions are resected and others fixed. The cause (which is usually shoulder instability), however, needs to be assessed and treated.

Outcomes of arthroscopic Hill-Sachs remplissage and anterior Bankart repair: a retrospective controlled study including ultrasound evaluation of posterior capsulotenodesis and infraspinatus strength assessment

BACKGROUND

Hill-Sachs lesions are compression fractures that result from shoulder dislocation. They involve "engaging" the humeral head on the anterior glenoid rim when the arm is abducted and externally rotated. The defect grows as the number of dislocations increases.

HYPOTHESIS

Arthroscopic remplissage and anterior Bankart repair do not significantly affect infraspinatus strength while ensuring healing of the capsulotenodesis.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Sixty-one patients with traumatic anterior shoulder instability treated by arthroscopic Bankart repair and Hill-Sachs remplissage at least 24 months previously were compared with a control group of 40 healthy participants. Preoperative imaging included magnetic resonance imaging for Bankart lesion identification and computed tomography to quantify the humeral head defect. Active range of motion and clinical scores (Walch-Duplay, Constant-Murley, and Rowe) were assessed. External rotation (ER) and internal rotation (IR) were measured with arm at the side (ER1 and IR1) and abducted at 90° (ER2 and IR2). Infraspinatus strength was assessed with the scapula free (infraspinatus strength test [IST]) and retracted (infraspinatus scapula retraction test [ISRT]). Infraspinatus tenodesis and posterior capsulodesis healing were evaluated by ultrasound (US).

RESULTS

The follow-up median was 39.5 months (range, 24-56 months). One patient experienced a recurrence of instability at 34 months. In the remplissage patients, ER1 was significantly lower in the affected compared with the unaffected shoulder (P < .001). Mean IST and ISRT strength values did not show differences between sides. The mean Constant-Murley score rose from 62.9 ± 7.1 to 90 ± 5.2 (P < .0001). The Walch-Duplay and Rowe scores were excellent in 23 (78.6%), good in 6 (17.8%), and poor in 1 patient (both scores). The remplissage group had significantly lower ER1 (P < .001), ER2 (P < .001), and IR2 (P < .01) values compared with the control group. Differences in IST and ISRT between the groups were not significant. Capsulotenodesis healing and filling of the Hill-Sachs defect were confirmed by dynamic US in all subjects.

CONCLUSION

Arthroscopic remplissage is a reliable approach to Hill-Sachs lesions. The ER and IR restriction does not significantly affect quality of life. Infraspinatus strength recovery is satisfactory even compared with healthy subjects. Ultrasound examination allows accurate evaluation of capsulotenodesis healing.

Arthroscopic Bristow-Latarjet combined with bankart repair restores shoulder stability in patients with glenoid bone loss

BACKGROUND

Arthroscopic Bankart repair alone cannot restore shoulder stability in patients with glenoid bone loss involving more than 20% of the glenoid surface. Coracoid transposition to prevent recurrent shoulder dislocation according to Bristow-Latarjet is an efficient but controversial procedure.

QUESTIONS/PURPOSES

We determined whether an arthroscopic Bristow-Latarjet procedure with concomitant Bankart repair (1) restored shoulder stability in this selected subgroup of patients, (2) without decreasing mobility, and (3) allowed patients to return to sports at preinjury level. We also evaluated (4) bone block positioning, healing, and arthritis and (5) risk factors for nonunion and coracoid screw pullout.

METHODS

Between July 2007 and August 2010, 79 patients with recurrent anterior instability and bone loss of more than 20% of the glenoid underwent arthroscopic Bristow-Latarjet-Bankart repair; nine patients (11%) were either lost before 2-year followup or had incomplete data, leaving 70 patients available at a mean of 35 months. Postoperative radiographs and CT scans were evaluated for bone block positioning, healing, and arthritis. Any postoperative dislocation or any subjective complaint of occasional to frequent subluxation was considered a failure. Physical examination included ROM in both shoulders to enable comparison and instability signs (apprehension and relocation tests). Rowe and Walch-Duplay scores were obtained at each review. Patients were asked whether they were able to return to sports at the same level and practice forced overhead sports. Potential risk factors for nonhealing were assessed.

RESULTS

At latest followup, 69 of 70 (98%) patients had a stable shoulder, external rotation with arm at the side was 9° less than the nonoperated side, and 58 (83%) returned to sports at preinjury level. On latest radiographs, 64 (91%) had no osteoarthritis, and bone block positioning was accurate, with 63 (90%) being below the equator and 65 (93%) flush to the glenoid surface. The coracoid graft healed in 51 (73%), it failed to unite in 14 (20%), and graft osteolysis was seen in five (7%). Bone block nonunion/migration did not compromise shoulder stability but was associated with persistent apprehension and less return to sports. Use of screws that were too short or overangulated, smoking, and age higher than 35 years were risk factors for nonunion.

CONCLUSIONS

The arthroscopic Bristow-Latarjet procedure combined with Bankart repair for anterior instability with severe glenoid bone loss restored shoulder stability, maintained ROM, allowed return to sports at preinjury level, and had a low likelihood of arthritis. Adequate healing of the transferred coracoid process to the glenoid neck is an important factor for avoiding persistent anterior apprehension.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Enlargement of Glenoid Defects in Traumatic Anterior Shoulder Instability: Influence of the Number of Recurrences and Type of Sport

Background:

Large glenoid rim defects in patients with traumatic anterior shoulder instability are often regarded as a contraindication for arthroscopic Bankart repair, with a defect of 20% to 27% considered as the critical size. While recurrence of dislocations, male sex, and collision sports were reported to be the significant factors influencing large glenoid defects, the influences of subluxations and more detailed types of sports were not investigated.

Purpose:

To investigate the influence of the number of dislocations and subluxations and type of sport on the occurrence and size of glenoid defects in detail.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

A total of 223 shoulders (60 with primary instability, 163 with recurrent instability) were prospectively examined by computed tomography. Glenoid rim morphology was compared between primary and recurrent instability. In patients with recurrent instability, the relationship between the glenoid defect and the number of dislocations and subluxations was investigated. In addition, glenoid defects were compared among 49 male American football players, 41 male rugby players, 27 male baseball players, and 25 female athletes.

Results:

The mean extent of the glenoid defect was 3.5% in shoulders with primary instability and 11.3% in those with recurrent instability. A glenoid defect was detected in 108 shoulders (66.2%) with recurrent instability versus 12 shoulders (20%) with primary instability. Regarding the influence of the total number of dislocations/subluxations, the average extent of the glenoid defect was 6.3% in 85 shoulders with 2 to 5 events, 12.9% in 34 shoulders with 6 to 10 events, and 19.6% in 44 shoulders with 11 or more events. The glenoid defect became significantly larger along with an increasing number of recurrences. Although recurrent subluxation without dislocation also influenced the glenoid defect size, the number of dislocations did not. The average extent of the glenoid defect was 12.0% in rugby players, 8.9% in American football players, 4.7% in female athletes, and 4.5% in baseball players. Glenoid defects were significantly smaller in male baseball players and female athletes than in male collision athletes.

Conclusion:

The glenoid defect is significantly enlarged by damage due to recurrent dislocation and subluxation; therefore, glenoid rim morphology differs markedly between primary and recurrent instability. Glenoid defect size is also influenced by sex and by the type of sport.

Arthroscopic repair of small and medium-sized bony Bankart lesions

BACKGROUND

There has been no study about treatment guidelines for arthroscopic repair according to the size of bony Bankart lesions of less than 25% of the glenoid width.

PURPOSE

To evaluate the results of arthroscopic repair for bony Bankart lesions managed with different repair techniques based on their size.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between March 2005 and February 2009, 44 of 52 consecutive patients with bony Bankart lesions with a size of less than 25% of the entire glenoid were managed with an arthroscopic approach. Of those patients, 34 (77%) were available for outcome analysis at a minimum 24 months' follow-up (mean, 34 months; range, 24-60 months). The size of the fragment was measured by computed tomography (CT) and classified as small (<12.5% of the inferior glenoid width) and medium (12.5%-25%). Sixteen lesions were classified as small (small group), and 18 were classified as medium (medium group). For small lesions, capsulolabral repair using suture anchors without excision of the bony fragment was performed. For medium lesions, anatomic reduction and fixation using suture anchors was performed, and the adequacy of reduction was assessed by CT postoperatively. The visual analog scale (VAS) for pain score and modified Rowe score for bony Bankart repair were compared and the postoperative recurrence rate investigated.

RESULTS

One patient from the small group (6.3%) and 1 patient without anatomic reduction of the bony fragment in the medium group (5.6%) experienced traumatic redislocations. The mean VAS score improved from 1.7 preoperatively to 0.5 at final follow-up, and the mean Rowe score improved from 59 to 91 (both P < .001). The mean postoperative Rowe scores increased from 58 to 92 in the small group and from 60 to 91 in the medium group (both P < .001). Residual joint incongruity measuring ≤2 mm on both axial and coronal scans, which was considered an anatomic reduction, was present in 14 cases (77.8%) in the medium group. In the medium group, the mean postoperative Rowe scores increased from 60 to 95 in cases of anatomic reduction compared with an increase from 56 to 76 in cases of nonanatomic reduction. The Rowe score was statistically correlated with anatomic reduction of medium-sized bony fragments (P = .046).

CONCLUSION

In small Bankart lesions, restoration of capsulolabral soft tissue tension alone may be enough, whereas in medium lesions, the osseous architecture of the glenoid should be reconstructed for more functional improvement and less pain.

Simple method of glenoid bone loss calculation using ipsilateral magnetic resonance imaging

BACKGROUND

Current methods for estimating glenoid bone loss in patients with chronic shoulder instability include computed tomography imaging with 3-dimensional reconstruction, specialized computer software, and imaging of the contralateral shoulder. An ideal method of glenoid measurement would require only magnetic resonance imaging (MRI) of the injured shoulder.

PURPOSE

To determine whether MRI measurement of glenoid height, as well as sex, could be used to estimate glenoid width in healthy subjects with no history of shoulder instability.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Bilateral shoulder MRIs were obtained in a healthy cohort of young athletes as part of the baseline assessment in a prospective cohort study. A musculoskeletal radiologist measured glenoid height and width using the sagittal MRI cuts. Univariate and multivariate regression analyses were performed to determine whether demographic and MRI measurements of the glenoid could be used to estimate glenoid width.

RESULTS

Of the 1264 shoulder MRIs evaluated, the mean glenoid width was 26.67 mm (±2.49 mm), and the mean glenoid height was 42.15 mm (±3.00 mm). There were significant differences between the 129 female glenoids and the 1035 male glenoids for both width (23.1 mm, 27.1 mm, respectively, P < .0001) and height (37.9 mm, 42.7 mm, respectively, P < .0001); however, the relationship between glenoid height and width was similar for both men and women. The glenoid width was found to correlate with the height measurement (r = 0.56) for the entire cohort. Based on the results of linear regression analysis, controlling for the influence of sex, a formula was created that represents the relationship between these variables for male subjects: Glenoid Width = (1/3 Height) + 15 mm. Female patients are estimated with a formula that represents the same slope but a different intercept: W = 1/3 H + 13 mm.

CONCLUSION

Significant differences in glenoid height and width were found by sex; however, the relationship between height and width was similar. These variables are correlated, and the resultant formula can be used to estimate the expected glenoid width in a patient with bone loss. This formula allows for easy calculation of the amount of glenoid bone loss with only a ruler and an MRI of the injured shoulder.

Bone loss in anterior instability

Bone loss is commonly observed in shoulders with anterior instability. The Latarjet procedure is commonly performed when a glenoid bony defect exists that is greater than 25 % of the glenoid width or when the risk of recurrent instability is higher (i.e., collision-sport athletes). Hill-Sachs lesions need to be assessed as well. For the purpose of assessing the bipolar lesions, the glenoid track concept is useful. A Hill-Sachs lesion that is located more medially than the medial margin of the glenoid track is defined as an engaging Hill-Sachs lesion. A potential treatment for such a condition is remplissage, but this procedure also decreases range of motion. Thus, its application in overhead athletes needs to be carefully considered.

Relationship between the extent of labral lesions and the frequency of glenohumeral dislocation in shoulder instability

PURPOSE

This study aimed to evaluate the relationship between the extent of the labral lesion and the frequency of glenohumeral dislocation in patients with shoulder instability.

METHODS

Ninety-three patients, who underwent surgical treatment at our clinic for chronic anterior shoulder dislocation, were selected and divided into 3 groups (group I: only Bankart lesion; group II: Bankart and SLAP lesions; group III: circumferential-labral lesion). The pre-operative frequency of dislocation, intraoperative findings, operation time, post-operative clinical score, and range of motion 2 years after surgery were analysed and compared among the 3 groups.

RESULTS

The time interval from the initial dislocation to operation was significantly shorter in group III than in groups I and II (P = 0.034 and P = 0.046, respectively). The median number of preoperative dislocations was also significantly less in group III than in groups I and II (P = 0.025 and P = 0.044, respectively). In all groups, the clinical scores (Constant, Rowe, and visual analogue scale) improved significantly post-operatively, and there were no significant differences in the scores between the different groups. All patients returned to work, and most patients returned to their preoperative sports activity levels.

CONCLUSION

The extent of the labral lesion is not always related to the number of dislocations; therefore, treatment should not be based on this.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

ORV Arthroscopic Transosseous Bony Bankart Repair

The arthroscopic treatment of the "bony Bankart lesion" continues to evolve. We present a novel technique that we developed at Orthopaedic Research of Virginia, the "transosseous bony Bankart repair," which incorporates several essential concepts to provide for optimal healing and rehabilitation. We promote arthroscopic repair emphasizing bone preservation, a fracture interface without interposing sutures, the ability to reduce capsular volume, and multiple points of stable glenolabral fixation. Our technique positions suture anchors within the subchondral bone of the intact glenoid to allow for an anatomic reduction of the bony fragment. By use of an arthroscopic drill, spinal needle, and nitinol suture passing wire, the sutures are passed in a retrograde fashion through the bony Bankart fragment and anterior capsule in a mattress configuration. Additional inferior and superior anchors are placed to further provide stability and reduce capsular volume. While maximizing fracture surface area and optimizing bony healing, the end result is an anatomic reduction of the bony fragment and the glenoid articular surface.