Recurrent posterior shoulder instability

High Incidence of Anterior Shoulder Pain in Young Athletes Undergoing Arthroscopic Posterior Labral Repair for Posterior Shoulder Instability

Purpose

The purposes of this study were to determine the incidence of anterior shoulder pain in young athletes undergoing arthroscopic posterior labral repair for symptomatic unidirectional posterior shoulder instability and in patients with preoperative anterior shoulder pain treated without biceps tenodesis at the time of arthroscopic posterior labral repair who underwent a revision biceps tenodesis procedure at short-term follow up.

Methods

A retrospective review was performed at a single institution over a 24-month period. The study included young patients who underwent an arthroscopic posterior labral repair for symptomatic unidirectional posterior shoulder instability. The electronic medical record, magnetic resonance arthrograms, and arthroscopic images were reviewed to exclude patients with posterior labral tears with anterior labral tear or SLAP (superior labrum anterior-to-posterior) tear extension on advanced imaging and arthroscopic examination. Data collected included the presence of preoperative tenderness to palpation of the biceps tendon in the groove, the results of a preoperative Speed test, postoperative Subjective Shoulder Value, the presence of postoperative anterior shoulder pain, and the need for a secondary biceps tenodesis.

Results

We identified 65 patients who underwent arthroscopic labral repair for posterior shoulder instability. From this cohort, 26 patients with symptomatic unidirectional posterior shoulder instability underwent an arthroscopic posterior labral repair. The incidence of preoperative anterior shoulder pain with Zone 2 biceps groove tenderness and a positive Speed test was identified in 20 of 26 patients (76.9%). Of 26 patients, 5 (19%) had concomitant biceps tenodesis. The median postoperative Subjective Shoulder Value was 80 (interquartile range, 60-90) at median follow-up of 2.1 years. Of the 20 patients with preoperative anterior shoulder pain, 8 of 20 (40%) reported persistent anterior pain. One patient (4.7%) underwent a secondary biceps tenodesis.

Conclusions

There is a high incidence of anterior shoulder pain and Zone 2 biceps groove tenderness in patients undergoing isolated arthroscopic posterior labral repair for unidirectional posterior shoulder instability. At short-term follow-up, few patients required a secondary biceps tenodesis procedure; however, 30% of patients had persistent anterior shoulder pain.

Level of Evidence

Level IV, retrospective diagnostic case series.

Epidemiology of Shoulder Instability in the National Football League

Background

Shoulder instability is a common and potentially debilitating injury among collision sport athletes that can lead to long-term damage of the glenohumeral joint. Limited data exist regarding instability among elite athletes in the National Football League (NFL).

Purpose

To describe the epidemiology of shoulder instability in the NFL from 2012 through 2017.

Study Design

Descriptive epidemiology study.

Methods

The NFL's injury database was reviewed for shoulder instability injuries resulting in missed time during the study inclusion dates. Injuries were classified by type and direction, as well as timing, setting, and mechanism. Median missed time was determined for the different types and directions of instability. Incidence rates for game-related injuries were calculated based on timing during the season and player position. Finally, the relationship between player position and instability direction was assessed.

Results

During the 6-year study period, 355 players sustained 403 missed-time shoulder instability injuries. Most injuries occurred during games (65%) via a contact mechanism (85%). The overall incidence rate of game-related instability was 3.6 injuries per 100,000 player-plays and was highest during the preseason (4.9 per 100,000 player-plays). The defensive secondary position accounted for the most injuries, but quarterbacks had the highest incidence rate in games (5.5 per 100,000 player-plays). Excluding unspecified events (n = 128; 32%), 70% (n = 192) of injuries were subluxations and 30% (n = 83) were dislocations; 75% of dislocations were anterior, while subluxations were more evenly distributed between the anterior and posterior directions (45% vs 52%, respectively). Players missed substantially more time after dislocation compared with subluxation (median, 47 days vs 13 days, respectively). When instability direction was known, the majority of instability events among quarterbacks and offensive linemen were posterior (73% and 53%, respectively), while anterior instability was most common for all other positions.

Conclusion

Shoulder instability is a common injury in the NFL and can result in considerable missed time. Dislocations occur less frequently than subluxations but lead to greater time lost. While most dislocations are anterior, more than half of subluxations are posterior, which is likely the result of repetitive microtrauma to the posterior capsulolabral complex sustained during sport-specific motions such as blocking. The risk of instability varies by player position, and position may also influence instability direction.

Posterior Glenoid Reconstruction Using a Distal Tibial Allograft

Posterior shoulder instability is increasingly recognized and diagnosed in young athletes. These patients often present with vague shoulder pain rather than the frank instability commonly seen with anterior instability. Three common causes of posterior shoulder instability are congenital retroversion, a single traumatic event, or repetitive microtrauma with erosive effects. The critical determination when deciding on the appropriate treatment of posterior shoulder instability is the presence and degree of glenoid bone loss. In patients without bone loss, arthroscopic procedures have a high success rate with a failure rate of less than 10% and an 89% return-to-sport rate. The determination of the critical amount of bone loss that would permit an arthroscopic procedure is controversial, but recent reports that attempt to quantify the critical bone loss value posteriorly have ranged from 13.5% to 20%. This Technical Note describes our preferred method of open surgical treatment of posterior shoulder instability with posterior glenoid bone loss using an intra-articular distal tibial allograft.

Arthroscopic Posterior Glenoid Reconstruction Using a Fresh Distal Tibia Allograft for Recurrent Posterior Instability

Posterior glenohumeral instability is a relatively uncommon cause of shoulder instability. Recurrent posterior instability with static posterior humeral head subluxation is often associated with critical glenoid bone loss. Unlike anterior instability, the amount of bone loss for posterior instability that requires surgical reconstruction remains a topic of debate. Several techniques have been described to treat critical bony defects in patients with recurrent posterior shoulder instability with the use of both autografts and allografts depending on the amount of bone loss present. Open posterior glenoid bone block procedure is associated with increased risk of complications and morbidity to the patient. As such, all-arthroscopic techniques have emerged with the advantage of allowing for the diagnosis and treatment of concomitant glenohumeral pathology and minimizing soft-tissue dissection through the posterior deltoid and rotator cuff muscles. Reported short-term outcomes of arthroscopic posterior bone block stabilization are promising; however, it remains a technically challenging procedure due to intra-articular graft insertion and subsequent fixation congruent to the posterior glenoid articular margin. We describe an all-arthroscopic technique using a fresh distal tibia allograft fixation using 2 partially threaded screws in conjunction with an arthroscopic Latarjet fixation set for a patient with recurrent posterior shoulder instability and associated glenoid bone loss.

Arthroscopic Knotless Subscapularis Bridge Technique for Reverse Hill-Sachs Lesion With Posterior Shoulder Instability

Posterior shoulder dislocations are an uncommon cause of glenohumeral instability; they are frequently missed and are associated with humeral head defects and capsulolabral lesions. Despite surgical treatment often being mandatory, there is still no standardized treatment for anterior impaction fractures of the humeral head (reverse Hill-Sachs lesions). Arthroscopic surgery is typically indicated, with a tendency toward resorting to knotless techniques in recent years. We present a method for the treatment of posterior shoulder dislocations with engaging reverse Hill-Sachs lesions that achieves full defect coverage using an arthroscopic all-in-the-box knotless subscapularis bridge technique with 2 anchors-with one crossing the subscapularis tendon and the other embracing it-along with posterior capsulolabral complex restoration. This promising technique is a potentially superior alternative for the treatment of these lesions that can also be used in the presence of concomitant partial subscapularis tears.

Return to Sport After Arthroscopic Treatment of Posterior Shoulder Instability

Background:

Arthroscopic treatment of posterior shoulder instability has become more popular and effective in recent years, but few data are available concerning the rate of return to sport.

Purpose:

To present our experiences with arthroscopic posterior labral reconstruction in athletes and review our results, with a particular focus on the rate of return to sport.

Study Design:

Case series; Level of evidence, 4.

Methods:

Included in the study were 40 arthroscopic stabilizations performed because of posterior shoulder instability in 37 athletes at a single institution. During follow-up, the athletes’ rate of return to sport was calculated. Shoulder function was evaluated based on a pre- versus postoperative comparison of the Rowe instability score and the American Shoulder and Elbow Surgeons score. Additionally, the return-to-sport rate was compared among different subgroups: traumatic versus atraumatic origin of injury, competitive versus recreational athletes, high-risk versus low-risk sport, and posterior-only versus anterior and posterior stabilization. Data were statistically analyzed using paired-samples t test and nonparametric Fisher exact test.

Results:

The average follow-up period was 54.4 months (range, 24-112 months). Three shoulders (7.5%) continued to have posterior subluxations postoperatively. There were 34 excellent, 3 good, and 3 fair results based on the Rowe score (average postoperative score, 92.9), and patients achieved an average postoperative American Shoulder and Elbow Surgeons score of 92.7. The pre- to postoperative improvement was statistically significant in both scoring systems (P < .001). Of the 37 patients, 36 (98.2%) were able to return to sport activity: 27 of them (72.9%) to their original sport and 19 (51.4%) at their preinjury level. A significantly higher rate of return to the same sport occurred in athletes who had traumatic injury compared with a subgroup of athletes without a traumatic event (P < .02).

Conclusion:

More than half of the athletes were able to return to their preinjury level of sport after arthroscopic posterior labral reconstruction. In addition, low recurrence rates and good functional outcomes were seen in >90% of the patients, and 98% returned to sport activity. The athletes had a significantly higher rate of return to sport if their posterior shoulder instability had a clear traumatic origin.

Anterior Capsule Augmentation and Posterior Glenohumeral Capsular Reconstruction With Human Dermal Allograft for Multidirectional Shoulder Instability

Recurrent multidirectional shoulder instability is a common clinical presentation in certain demographics and sporting groups. One such demographic is patients with connective tissue disorders (CTD) such as Ehlers-Danlos syndrome (EDS), in whom shoulder pathologies are exacerbated owing to ligamentous laxity. Features of this laxity can present as both anterior and posterior shoulder instability, which are problematic sources of shoulder pain. Many patients with these injuries require surgical anterior and/or posterior glenohumeral reconstruction. Surgical reconstruction for posterior capsular defects can be challenging and has higher failure rates compared with anterior capsular reconstruction methods. Management can be especially difficult for patients with CTDs, and there is a requirement for the development of novel surgical techniques. Human acellular dermal allografts have been found to be particularly useful for patients with CTDs compared with other methods that use the patient's own tissue for the repair. This note and surgical video describe an all-arthroscopic technique for a combined anterior capsule augmentation and posterior glenohumeral capsular reconstruction, using a human acellular dermal allograft for EDS patients with multidirectional instability.

Low Risk of Recurrence After Posterior Labral Repair of the Shoulder in a High-Risk United States Military Population

Purpose

To examine the results of isolated arthroscopic posterior labral repair of the shoulder in an active military population, looking specifically at the reoperation rate and rate of return to previous military activity with a minimum follow-up period of 2 years.

Methods

A retrospective case series was performed in active-duty military service members who underwent isolated, primary arthroscopic posterior labral repair at a single academic military treatment facility between 2009 and 2015 and had at least 2 years of follow-up. Patients were excluded if they were of non–active-duty status, had insufficient follow-up (<2 years), or had undergone a concurrent procedure. Injury presentation, demographic data, and surgical data (i.e., surgical positioning, number of anchors, and anchor placement location) were compiled manually. Outcomes including the rate of return to active duty, recurrence of symptoms, and need for revision surgery were evaluated.

Results

Sixty-five patients were included. After arthroscopic repair, a high rate of return to previous military duties (83%) was noted at short- to mid-term follow-up (mean ± standard deviation, 3.04 ± 1.30 years), with 1 patient (1.5%) requiring revision arthroscopic repair and 10 patients (15.5%) showing activity-limiting shoulder pain preventing a return to active duty. Intraoperative positioning (P = .17), a low anchor position (P = .27), and the number of anchors used (P = .62) were not found to be significant contributors to continued postoperative pain or recurrent instability.

Conclusions

Arthroscopic intervention resulted in a reliable rate of glenohumeral stability with a low rate of surgical revision and a high rate of return to military duty at short- to mid-term follow-up. However, 1 in 6 military service members showed significant, activity-limiting shoulder pain postoperatively that did not permit a return to previous military activities after surgical intervention.

Level of Evidence

Level IV, therapeutic case series.

History of surgical stabilization for posterior shoulder instability

Background

Posterior shoulder instability is common in young athletes. Although the posterior shoulder instability literature is less robust than its anterior counterpart, many surgical procedures have been developed and refined over the past several centuries to address this condition.

Materials and methods

This article represents a retrospective historical analysis of the most common procedures used to treat posterior shoulder instability after sports injuries. A systematic approach to obtain published information on posterior shoulder instability was performed using the PubMed/MEDLINE database, manual searches of high–impact factor journals, and conference proceedings and books.

Results

A wide array of both soft tissue–based and bone-based procedures have been developed for the treatment of posterior shoulder instability, ranging from procedures addressing the soft tissue alone (capsular shift, labral repair, reverse Putti-Platt) or bone-based procedures (glenoid and/or humeral osteotomy, glenoid bone block) to a combination of both bone and soft-tissue procedures (modified McLaughlin procedure).

Discussion

Over the past several centuries, a number of procedures have been developed to address posterior shoulder instability, particularly as this pathology has become better understood. Future work is required not only to continue to advance these procedures but also to assess their outcomes. An understanding of the historical perspective of posterior shoulder instability procedures is essential as surgeons continue to modify these procedures in an effort to best help their patients.

Nonoperative Management of Posterior Shoulder Instability: An Assessment of Survival and Predictors for Conversion to Surgery at 1 to 10 Years After Diagnosis

PURPOSE

To (1) define the rate of delayed surgery, between 1 and 10 years after injury, in a population-based study of patients with posterior shoulder instability (PSI), (2) evaluate predictive factors associated with delayed repair, and (3) identify differences between the nonoperative and operative groups at long-term follow-up.

METHODS

A population-based retrospectively reviewed study of all patients with PSI from January 1, 1994, to December 31, 2015, was performed. Inclusion required a clinical diagnosis of PSI combined with supporting imaging. Complete medical records were reviewed for 2,091 potential cases. Kaplan-Meier estimates were used to calculate survival. Landmark survival analysis was performed to identify predictors of conversion to surgery.

RESULTS

The study included 143 patients with PSI, 79 of whom were managed nonoperatively for at least 1 year after diagnosis. After the first year, survival free of surgery was 78.3% at 1 year, 63.1% at 5 years, and 51.5% at 10 years. There was a trend toward increased surgery in patients with a body mass index > 35 (P = .10; hazard ratio = 2.32; confidence interval, 0.8-6.8). Nonthrowing athletes (including contact/weight-lifting athletes) showed a trend toward an increased risk for surgery (P = .07). Patients who underwent surgery were significantly more likely to have progression in arthritis (P = .02; hazard ratio = 4.0; confidence interval, 1.2-13.2).

CONCLUSIONS

Nonoperative management was performed for at least 1 year in over half of patients diagnosed with PSI. Overall, long-term follow-up demonstrates that 46% of these patients converted to surgery between 1 and 10 years after initial diagnosis. Ultimately, 70% of patients diagnosed with PSI go on to surgical intervention. Patients who underwent surgery at any time point were at an increased risk of radiographic progression of arthritis at a minimum of 5 years of follow-up.

LEVEL OF EVIDENCE

Level III, cohort study.

Bone block procedures for glenohumeral joint instability

Glenoid bone loss is a well established cause of instability and long term morbidity if not adequadely addressed. Anterior glenohumeral instability due an anterior glenoid defect is significantly more common, and for many years has been well treated with open anterior bone block augmentation procedures, most commonly the latarjet procedure. However, with refinement of this technique and some interest in reducing morbidity associated with iliac crest bone harvest, arthroscopic bone block procedures with allograft has become more popular. In this article we will review some of the key available evidence. We will also review management of the less common and more challenging posterior glenoid defects associated with posterior instability.

Effect of Posterior Glenoid Labral Tears at the NFL Combine on Future NFL Performance

Background:

Posterior labral injuries have been recognized as a particularly significant clinical problem in collision and contact athletes.

Purpose:

To evaluate the effect that posterior labral tears have on early National Football League (NFL) performance based on position, associated injuries, and operative versus nonoperative management.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective review of all participants in the NFL Combine from 2009 to 2015 was performed using medical and imaging reports documented at the combine. Magnetic resonance imaging scans were analyzed for tear location, associated injuries, and evidence of previous surgical interventions. Each player’s NFL draft position, as well as number of games played, number of games started, and snap percentage in his first 2 NFL seasons were collected for performance analysis and were compared with a control group of uninjured counterparts.

Results:

Players with posterior labral tears were selected significantly later in the draft than those in the control group (draft position, 171.6 vs 156.1, respectively; P = .017). Although no single individual position was significantly affected by posterior labral tears, linemen (both offensive and defensive) with posterior labral tears were drafted significantly later than those without tears (draft position, 164.0 vs 137.7, respectively; P = .018) and had a significantly lower percentage of snaps in their first NFL season (23.8% vs 27.7%, respectively; P = .014). Players who underwent surgical management before the combine had a significantly higher percentage of snaps in their second NFL season than those who were managed conservatively (31.4% vs 22.3%, respectively; P = .022). None of the concomitant injuries recorded (superior labral anterior-posterior tears, glenoid bone loss, reverse Hill-Sachs lesions, rotator cuff tears, reverse humeral avulsions of the glenohumeral ligament, and posterior labral tears combined with anterior tears) significantly affected the draft position, number of games played, number of games started, or snap percentage for the cohort as a whole or any specific position.

Conclusion:

Posterior labral tears did negatively and significantly affect early NFL outcomes for collegiate football players across several different metrics, especially among linemen. While operative management did not produce significantly superior performance in most outcome measures, it may allow for better longevity of the shoulder and warrants further investigation. Concomitant shoulder injuries did not significantly affect early NFL outcomes in this cohort.

Comparison of a Distal Tibial Allograft and Scapular Spinal Autograft for Posterior Shoulder Instability With Glenoid Bone Loss

Background

Posterior glenoid bone deficiency can occur with recurrent glenohumeral instability. Glenoid reconstruction with a distal tibial allograft (DTA) has been reported to successfully restore contact pressures that occur during posterior glenohumeral translation. However, there are concerns regarding the risk of allograft resorption, availability, and costs. Extracapsular reconstruction using a scapular spinal autograft (SSA) has been reported as an alternative technique secondary to its anatomic location relative to the posterior shoulder and preferable autograft properties. There are no known prior biomechanical studies evaluating the scapular spine as an effective extracapsular graft choice.

Purpose

To compare the efficacy of a DTA and SSA in restoring the stability of a glenoid with a large posterior bone defect compared with the intact native glenoid.

Study Design

Controlled laboratory study.

Methods

Ten cadaveric shoulders were tested. With the use of a custom KUKA robot, a 50-N compressive force was applied to the glenohumeral joint. The peak force required to translate the humeral head beyond the glenoid lip posteriorly as well as the lateral displacement that occurred during posterior translation were measured. Testing was performed in 5 conditions: (1) intact glenoid and labrum, (2) simulated reverse Bankart lesion, (3) 12-mm posterior glenoid defect, (4) glenoid defect reconstructed with a fresh DTA, and (5) glenoid defect reconstructed with an SSA.

Results

The mean glenoid width was 30 mm. The mean peak force and lateral displacement decreased significantly with a glenoid defect (0.99 ± 2.3 N and 0.06 ± 0.09 mm, respectively; P < .0001) compared with the intact glenoid (23.00 ± 9.7 N and 1.83 ± 0.70 mm, respectively; P = .0001). There was no significant difference between the peak force after reconstruction of the defect with a DTA (23.00 ± 7.4 N) and SSA (23.00 ± 7.7 N) when compared with the intact glenoid (P = .9999). There were no significant differences in the peak force between the 2 grafts (P = .9999). Additionally, both the DTA (1.04 ± 1.09 mm) and the SSA (1.02 ± 1.17 mm) demonstrated no differences in lateral displacement when compared with the intact glenoid (P = .2336 and .2043, respectively). There was no difference in lateral displacement that occurred between the DTA and SSA (P = .9999).

Conclusion

Reconstruction of a large posterior glenoid defect with either a DTA or an SSA can effectively restore glenohumeral stability.

Clinical Relevance

This study supports the use of a DTA or SSA in posterior glenoid defect reconstruction. Clinical studies are needed to determine the long-term effects of utilizing such grafts.

Posterior Glenohumeral Capsular Reconstruction Using an Acellular Dermal Allograft

Posterior shoulder instability is an uncommon and challenging cause of shoulder pain and dysfunction. Surgical management has less reliable results and higher failure rates compared with techniques for anterior shoulder instability. The presence of generalized ligamentous laxity further complicates options for surgical management. If primary capsulolabral repair fails, controversy exists as to the optimal revision procedure. This technical description and video present an arthroscopic technique for reconstruction of the posterior glenohumeral capsule with an acellular dermal allograft to treat posterior instability in a patient with Ehlers-Danlos syndrome and a previously failed posterior capsular plication.

Critical Glenoid Bone Loss in Posterior Shoulder Instability

BACKGROUND

There is currently no consensus regarding the amount of posterior glenoid bone loss that is considered critical. Critical bone loss is defined as the amount of bone loss that occurs in which an isolated labral repair will not sufficiently restore stability.

PURPOSE

The purpose is to identify the critical size of the posterior defect.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eleven cadaveric shoulders were tested. With the use of a custom robot device, a 50-N compressive force was applied to the glenohumeral joint, and the peak force that was required to translate the humeral head posteriorly and the lateral displacement that occurred with translation were measured. The defect size was measured as a percentage of the glenoid width. Testing was performed in 11 conditions: (1) intact glenoid and labrum, (2) simulated reverse Bankart lesion, (3) the reverse Bankart lesion repaired, (4) a 10% defect, (5) the reverse Bankart lesion repaired, (6) a 20% defect, (7) the reverse Bankart lesion repaired, (8) a 30% defect, (9) the reverse Bankart lesion repaired, (10) a 40% defect, and (11) the reverse Bankart repaired.

RESULTS

Force and displacement decreased as the size of the osseous defect increased. The mean peak force that occurred with posterior displacement in specimens with a glenoid defect ≥20% and a reverse Bankart repair (13 ± 9 N) was significantly lower than the peak force that occurred in specimens with an isolated reverse Bankart repair (22 ± 10 N) ( P = .0451). In addition, the mean lateral displacement was significantly less in the specimens with a 20% glenoid defect and a reverse Bankart repair (0.61 ± 0.57 mm) compared with the lateral displacement that occurred in specimens with an isolated reverse Bankart repair (1.6 ± 0.78 mm) ( P = .0058).

CONCLUSION

An osseous defect that is ≥20% of the posterior glenoid width remains unstable after isolated reverse Bankart repair.

CLINICAL RELEVANCE

A bony restoration procedure of the glenoid may be necessary in shoulders with a posterior glenoid defect that is ≥20% of the glenoid width.

Evidence-Based Review of Clinical Diagnostic Tests and Predictive Clinical Tests That Evaluate Response to Conservative Rehabilitation for Posterior Glenohumeral Instability: A Systematic Review

Context:

Posterior glenohumeral instability is poorly understood and can be challenging to recognize and evaluate. Using evidence-based clinical and predictive tests can assist clinicians in appropriate assessment and management.

Objective:

To review evidence-based clinical diagnostic tests for posterior glenohumeral instability and predictive tests that identify responders to conservative management.

Data Sources:

A comprehensive electronic bibliographic search was conducted using Embase, Ovid MEDLINE, PEDro, and CINAHL databases from their date of inception to February 2017.

Study Selection:

Studies were included for further review if they (1) reported on clinical diagnostic tests for posterior or posteroinferior instability of the glenohumeral joint, (2) assessed predictive clinical tests for posterior instability of the glenohumeral joint, and (3) were in English.

Study Design:

Systematic review.

Level of Evidence:

Level 4.

Data Extraction:

Data were extracted from the studies by 2 independent reviewers and included patient demographics and characteristics, index/reference test details (name and description of test), findings, and data available to calculate psychometric properties.

Results:

Five diagnostic and 2 predictive studies were selected for review. There was weak evidence for the use of the jerk test, Kim test, posterior impingement sign, and O’Brien test as stand-alone clinical tests for identifying posterior instability. Additionally, there was weak evidence to support the use of the painless jerk test and the hand squeeze sign as predictive tests for responders to conservative management. These findings are attributed to study design limitations, including small and/or nonrepresentative samples.

Conclusion:

Clustering of thorough history and physical examination findings, including the aforementioned tests, may identify those with posterior glenohumeral instability and assist in developing management strategies.

[The ABC guide for the treatment of posterior shoulder instability]

BACKGROUND

Posterior glenohumeral instability (PGHI) is an often unrecognized or misdiagnosed type of shoulder instability due to its heterogenic clinical and radiological presentation.

CLASSIFICATION

The ABC classification for PGHI is based on the different pathomechanisms and recommended treatment standards and is therefore a guide to finding the correct diagnosis and therapy for affected patients. There are different types of PGHI: A (first time), B (dynamic), C (static). These groups are further classified based on pathomechanical principles: A1: subluxation, A2: dislocation; B1: functional, B2: structural; C1: constitutional, C2: acquired.

THERAPY

In patients with type 1 PGHI (A1, B1, C1) conservative treatment is recommended while in patients with type 2 PGHI (A2, B2, C2) surgical treatment can be considered based on structural defects, clinical symptoms, chronicity, age, functional demand, and patient-specific health status. In addition it has to be considered, that there is the possibility of coexisting or overlapping subtypes as well as the chance of progression from one category into another over time.

Arthroscopic posterior bone block stabilization-early results of an effective procedure for the recurrent posterior instability

PURPOSE

In the current study the clinical outcome of an arthroscopic posterior bone block augmentation in combination with a posterior capsular repair was investigated.

METHODS

Twenty-four shoulders (18 patients) with unidirectional posterior shoulder instability were treated with an arthroscopic posterior bone block and capsular reconstruction. The mean follow up period was 26 months. The patients were examined pre- and postoperatively using the Constant-Murley score, the Rowe score, Walch-Duplay score and Western Ontario Shoulder index.

RESULTS

At the follow up examination 21 shoulders were classified to be stable, while one patient reported a single redislocation and two further patients reported recurrent posterior subluxation or posterior apprehension. Thus, the recurrence rate was defined to be 12.5%. The Rowe-Score significantly improved from 50 points preoperatively to 75 points postoperatively (p = 0.0003). The WOSI-score significantly improved from 37% preoperatively to 66% postoperatively (p = 0.0001). Revision surgery commonly was required for screw removal.

CONCLUSION

The early clinical results of this arthroscopic bone block augmentation and capsular repair are promising.

LEVEL OF EVIDENCE

IV.

Clinical outcomes of posterior bone block procedures for posterior shoulder instability: Multicenter retrospective study of 66 cases

BACKGROUND

The posterior bone block procedure is a well-known treatment option for posterior shoulder instability. The goal of this retrospective multicenter study was to evaluate the clinical and radiological outcomes of this procedure.

MATERIAL AND METHODS

The study cohort consisted of 66 patients (55 men, 11 women) with an average age of 27.8 years who were evaluated clinically and radiologically using a standardized questionnaire after posterior bone block surgery.

RESULTS

The Constant score significantly improved postoperatively (P<0.0001). The postoperative Walch-Duplay score was 81.5. The Rowe score was 86.5 points. The pain level (VAS) was significantly reduced after this procedure (P<0.0001). Eighty-five percent of patients were satisfied or very satisfied with the outcome.

CONCLUSION

This multicenter study of 66 patients shows that the posterior bone block procedure is an effective technique with good subjective and objective outcomes; however, the possibility of complications cannot be ignored.

CLINICAL STUDY

Level of evidence IV.

Treatment of The Posterior Unstable Shoulder

BACKGROUND

It is estimated that approximately 5% of glenohumeral instabilities are posterior. There are a number of controversies regarding therapeutic approaches for these patients.

METHODS

We analyse the main surgery alternatives for the treatment of the posterior shoulder instability. We did a research of the publications related with posterior glenohumeral instability.

RESULTS

There are conservative and surgical treatment options. Conservative treatment has positive results in most patients, with around 65 to 80% of cases showing recurrent posterior dislocation. There are multiple surgical techniques, both open and arthroscopic, for the treatment of posterior glenohumeral instability. There are procedures that aim to repair bone defects and others that aim to repair soft tissues and capsulolabral injuries. The treatment should be planned according to each case on an individual basis according to the patient characteristics and the injury type. Surgical treatment is indicated in patients with functional limitations arising from instability and/or pain that have not improved with rehabilitation treatment. The indications for arthroscopic treatment are recurrent posterior subluxation caused by injury of the labrum or the capsulolabral complex; recurrent posterior subluxation caused by capsuloligamentous laxity or capsular redundancy; and multidirectional instability with posterior instability as a primary component. Arthroscopic assessment will help identify potential injuries associated with posterior instability such as bone lesions or defects and lesions or defects of soft tissues. The main indications for open surgery would be in cases of Hill Sachs lesions or broad reverse Bankart lesions not accessible by arthroscopy. We indicated non-anatomical techniques (McLaughlin or its modifications) for reverse Hill-Sachs lesions with impairment of the articular surface between 20% and 50%. Disimpaction of the fracture and placement of bone graft (allograft or autograft) is a suitable treatment for acute lesions that do not exceed 50% of the articular surface and with articular cartilage in good condition. Reconstruction with allograft may be useful in lesions affecting up to 50% of the humeral surface and should be considered when there is a situation of non-viable cartilage at the fracture site. For defects greater than 50% of the articular surface or in the case of dislocations over 6 months in duration where there is poor bone quality, some authors advocate substitution techniques as a treatment of choice. The main techniques for treating glenoid bone defects are posterior bone block and posterior opening osteotomy of the glenoid.

CONCLUSIONS

The treatment of the posterior glenohumeral instability has to be individualized based on the patient´s injuries, medical history, clinical exam and goals. The most important complications in the treatment of posterior glenohumeral instability are recurrent instability, avascular necrosis and osteoarthritis.

ABC classification of posterior shoulder instability

Posterior glenohumeral instability (PGHI) is a commonly under- and misdiagnosed pathology owing to its variety of clinical presentations. In order to facilitate diagnosis and treatment, the simple yet comprehensive ABC classification for PGHI is based on the underlying pathomechanical principles and current standard of treatment. Three main groups of PGHI are distinguished based on the type of instability: A (first time), B (dynamic), C (static). Two subtypes further differentiate these groups in terms of their specific pathomechanism and provide a guideline in the choice of appropriate treatment: A (1, subluxation; 2, dislocation), B (1, functional; 2, structural), C (1, constitutional; 2, acquired). While conservative treatment is warranted in most patients with type 1 PGHI (A1, B1, C1), surgical treatment should be considered on an individual basis in patients with type 2 PGHI (A2, B2, C2), while keeping in mind that the different groups and subtypes can overlap, co-exist, or even progress from one to another over time. Of course the necessity for surgical treatment depends on the extent of the structural defects, on the severity of symptoms, on the chronicity, as well as on patient-specific functional demand, age, and health status. Nonetheless, the ABC classification helps to correctly diagnose the type of PGHI and provides a guideline for the generally recommended type of treatment.

Evidence-based conservative rehabilitation for posterior glenohumeral instability: A systematic review

STUDY DESIGN

Systematic review.

OBJECTIVES

To identify the best evidenced-based approach for the conservative rehabilitation of patients with posterior glenohumeral instability.

BACKGROUND

Posterior glenohumeral instability is more common than previously thought. Proper management is imperative to control symptoms and maximize function.

METHODS

We conducted an electronic search, up to November 2014, for English-language studies involving rehabilitation of posterior shoulder instability. A manual search of reference lists of included articles and previously published reviews was also performed.

RESULTS

Five studies met the review inclusion criteria. Most studies demonstrated that rotator cuff and posterior deltoid strengthening could reduce instability recurrence and pain, and increase function, mainly in those with atraumatic posterior instability without previous surgery. These studies were mainly case series or retrospective designs.

CONCLUSIONS

Rotator cuff and posterior deltoid strengthening may help with symptom-management and functioning in those with posterior glenohumeral instability. Further research is needed to detect statistically significant outcomes from conservative treatment.

LEVEL OF EVIDENCE

Therapy, Level 3.

Posterior Shoulder Instability in Overhead Athletes

Posterior shoulder instability in overhead athletes presents a unique and difficult challenge. Often, this group has an inherent capsular laxity and/or humeral retroversion to accommodate the range of motion necessary to throw. This adaptation makes the diagnosis of posterior capsulolabral pathology challenging, as the examiner must differentiate between adaptive capsular laxity and pathologic instability. Further complicating matters, the intraoperative surgeon must find the delicate balance of achieving stability while still allowing the necessary range of motion.

Arthroscopic Repair of a Posterior Bony Bankart Lesion

Posterior bony defects of the glenoid rim, particularly those associated with instability, are often a frustrating challenge for arthroscopists because of the defects' inaccessibility from standard portals. This challenge is enhanced when the lesion is chronic and fibrous malunion of the fragment makes mobilization difficult. We present our technique for arthroscopic repair of the relatively uncommon chronic posterior bony Bankart lesion. By use of lateral positioning and a standard anterior viewing portal and posterior working portal, as well as a strategically placed posterolateral accessory portal, the lesion is first freed from its malreduced position and ultimately repaired using suture anchor fixation of the bony fragment along with its associated labrum directly to the remaining glenoid rim. This technique, facilitated by precise portal placement, results in satisfactory fragment reduction, appropriate capsular tension, and restoration of anatomy.

Arthroscopic Stabilization of Posterior Shoulder Instability Is Successful in American Football Players

PURPOSE

To evaluate subjective and objective clinical outcomes of arthroscopic posterior capsulolabral repair for the treatment of symptomatic unidirectional posterior shoulder instability in American football players.

METHODS

Fifty-six consecutive American football players with unidirectional posterior shoulder instability underwent an arthroscopic posterior capsulolabral repair with or without suture anchors. Patients were evaluated, with return to play as the primary outcome measure supplemented with the American Shoulder and Elbow Surgeons (ASES) scoring system. Stability, range of motion, strength, pain, and function were also assessed with subjective scales.

RESULTS

At a mean follow-up of 44.7 months postoperatively, 93% returned to sport and 79% returned to sport at the same level. Significant improvements (P < .01) were seen between preoperative and postoperative evaluations in ASES score and subjective scores of stability, range of motion, strength, pain, and function. Excellent or good results (ASES score > 60; stability < 6) were achieved in 96.5% of athletes, and 96% were satisfied with their operations.

CONCLUSIONS

Arthroscopic capsulolabral repair for unidirectional posterior shoulder instability is effective in American football players because it improves stability, pain, and joint function, which optimizes the likelihood of successful return to play.

LEVEL OF EVIDENCE

Case series; Level of evidence, IV.

Posteroinferior shoulder instability: clinical outcome of arthroscopic stabilization in 32 shoulders and categorization based on labral mapping

INTRODUCTION

Posterior shoulder instability is rare, appears in varying clinical patterns and can be the main symptom in patients with instability in more than one direction. The purpose was to analyze and categorize our patients and to report on the results of operative treatment by arthroscopy.

MATERIALS AND METHODS

A consecutive series of 32 shoulders in 31 patients from a 7-year period was chosen for retrospective clinical evaluation with VAS for pain, Rowe Score, Constant Score and Simple Shoulder Test. Follow-up rate was 100 %, the mean FU period was 28 months (range 13-58). Allocation based on clinical and intraoperative criteria resulted in the 4 groups A to D characterized by an increasing traumatic impact. Patients received a posterior Bankart repair with bone anchors in 21 or capsular plication to the intact labrum in 11 cases.

RESULTS

The clinical outcome scores were generally good and all showed a trend towards better results from A to D, but without significance. Pain on VAS pre- and postoperatively showed a significant (p < 0.0001) overall decline from 7.4 to 1.8. The Rowe Score increased significantly (p < 0.0001) from a mean value of 41.4 to 89.5 points. Three patients were reoperated and satisfied, four patients (12.5 %) not satisfied at follow-up. The drive-through sign was significantly (p = 0.003) more distinct in the less traumatic groups A and B than groups C and D. Subgroup allocation resulted in the following distribution: 7 patients qualified for group A (PPM = predominantly posterior multidirectional), 13 for B (RPS = recurrent posterior subluxation), 7 for C (unidirectional) and 5 patients for group D (bi-directional). Graphic display of labral lesions, called "labral mapping", revealed typical patterns for the groups.

CONCLUSION

In patients with posteroinferior shoulder instability, good results can be obtained with the arthroscopic treatment of all identified pathologies. Categorization into one of four subgroups might be a valuable tool regarding the choice of the operative treatment options.

Risk factors which predispose first-time traumatic anterior shoulder dislocations to recurrent instability in adults: a systematic review and meta-analysis

BACKGROUND

Recurrent instability following a first-time anterior traumatic shoulder dislocation may exceed 26%. We systematically reviewed risk factors which predispose this population to events of recurrence.

METHODS

A systematic review of studies published before 1 July 2014. Risk factors which predispose recurrence following a first-time traumatic anterior shoulder dislocation were documented and rates of recurrence were compared. Pooled ORs were analysed using random-effects meta-analysis.

RESULTS

Ten studies comprising 1324 participants met the criteria for inclusion. Recurrent instability following a first-time traumatic anterior shoulder dislocation was 39%. Increased risk of recurrent instability was reported in people aged 40 years and under (OR=13.46), in men (OR=3.18) and in people with hyperlaxity (OR=2.68). Decreased risk of recurrent instability was reported in people with a greater tuberosity fracture (OR=0.13). The rate of recurrent instability decreased as time from the initial dislocation increased. Other factors such as a bony Bankart lesion, nerve palsy and occupation influenced rates of recurrent instability.

CONCLUSIONS

Sex, age at initial dislocation, time from initial dislocation, hyperlaxity and greater tuberosity fractures were key risk factors in at least two good quality cohort studies resulting in strong evidence as concluded in the GRADE criteria. Although bony Bankart lesions, Hill Sachs lesions, occupation, physiotherapy treatment and nerve palsy were risk factors for recurrent instability, the evidence was weak using the GRADE criteria-these findings relied on poorer quality studies or were inconsistent among studies.

High frequency of posterior and combined shoulder instability in young active patients

OBJECTIVE

The purpose of this study was to describe the epidemiology and demographics of surgically treated shoulder instability stratified by direction. We hypothesized that there would be an increased frequency of posterior and combined shoulder instability in our population compared with published literature. Secondarily, we assessed preoperative magnetic resonance imaging (MRI) reports to determine how accurately they detected the pathology addressed at surgery.

MATERIALS AND METHODS

A retrospective review was conducted at a single facility during a 46-month period. The study included all patients who underwent an operative intervention for shoulder instability. The instability in each case was characterized as isolated anterior, isolated posterior, or combined, according to pathologic findings confirmed at arthroscopy. The findings were retrospectively compared with official MRI reports to determine the accuracy of MRI in characterizing the clinically and operatively confirmed diagnosis.

RESULTS

A consecutive series of 231 patients (221 men, 10 women) underwent stabilization for shoulder instability over 46 months. Patients were a mean age of 26.0 years. There were 132 patients (57.1%) with isolated anterior instability, 56 (24.2%) with isolated posterior instability, and 43 (18.6%) with combined instability. Overall, MRI findings completely characterized the clinical diagnosis and arthroscopic pathology in 149 of 219 patients (68.0%).

CONCLUSION

The rate of posterior and combined instability in an active population is more common than has been previously reported, making up more than 40% of operatively treated instability, including a previously unreported incidence of 19% for combined instabilities. In addition, MRI was often incomplete or inaccurate in detecting the pathology eventually treated at surgery.

Patient-reported outcomes following a physiotherapy rehabilitation programme for atraumatic posterior shoulder subluxation

BACKGROUND

There is a paucity of research that describes the patient-reported benefits of physiotherapy rehabilitation for atraumatic posterior instability despite non-operative treatment being considered the initial treatment of choice. This retrospective case series review describes the patient-reported outcomes following a physiotherapy rehabilitation programme for atraumatic posterior shoulder instability.

METHODS

Nineteen consecutive patients with a clinical diagnosis of atraumatic posterior shoulder subluxation completed our physiotherapy programme. All patients completed Oxford Instability Shoulder scores (OISS) and Western Ontario Shoulder Instability Index (WOSI) scores before and after physiotherapy intervention.

RESULTS

Patients reported a statistically significant clinical improvement in the main outcome measures following physiotherapy intervention. The OISS showed a mean improvement of 18.6 points, whereas the WOSI score showed a mean improvement of 37.2%. Following physiotherapy rehabilitation, all patients reported that their shoulder did not prevent them from performing their work/studies or their chosen hobbies/sports.

CONCLUSIONS

Our results support the view that specialized physiotherapy rehabilitation is a valuable treatment option for atraumatic posterior shoulder instability and reveal significant clinically important improvements in patient-reported outcomes.

Arthroscopic Posterior Stabilization of the Shoulder Using a Percutaneous Knotless Mattress Suture Technique

Posterior shoulder instability is far less common than anterior instability, and its arthroscopic treatment can be technically demanding. We describe a percutaneous arthroscopic technique for posterior shoulder stabilization using mattress sutures and knotless anchors. Spinal needles are used to pass the sutures percutaneously in a mattress fashion. Knotless anchors are used to secure the sutures under the labrum. These anchors can be used without cannulas, giving easier access to the posterior glenoid. This procedure is simple, cost-effective, and safe, avoiding the presence of both knots and suture strands in contact with the humeral head.

Revision posterior shoulder stabilization

BACKGROUND

Revision arthroscopic posterior glenohumeral stabilization requires a thorough understanding of the static and dynamic stabilizers of the glenohumeral joint. The evaluation of these patients is complex but critical given the variety of possible underlying lesions.

METHOD

We reviewed the literature surrounding recurrent and revision posterior instability biomechanics, etiology, evaluation, treatment, and outcomes. We also reviewed our own database of posterior instability cases and isolated revision procedures to review our own outcomes and to highlight overall concepts.

DISCUSSION/CONCLUSION

Although other authors have argued that performing a revision procedure indicates for an open procedure and osseous augmentation, our experience has been that revision posterior stabilization arthroscopic soft-tissue repair alone may be indicated in selected patients. After identification of posterior glenoid bone loss/effective retroversion and mechanical failure of prior repairs, the majority of the patients with recurrence of posterior instability likely have either recurrent or persistent labral pathology or patulous capsules with occult multi-directional instability primarily manifesting in the posterior direction. These patients are best served with capsular shift, reefing, and plication, often requiring 180-270° repair and 4 or greater suture anchors. Because of significant heterogeneity in the clinical outcomes reported to date further research will be necessary to define the clinical outcomes in revision posterior stabilization.

Modified arthroscopic McLaughlin procedure for treatment of posterior instability of the shoulder with an associated reverse Hill-Sachs lesion

Traumatic posterior shoulder dislocations are often accompanied by an impression fracture on the anterior surface of the humeral head known as a "reverse Hill-Sachs lesion". This bony defect can engage on the posterior glenoid rim and subsequently lead to recurrent instability and progressive joint destruction. We describe a new modified arthroscopic McLaughlin procedure, which allows for filling of the bony defect with the subscapularis tendon and subsequently prevents recurrence of posterior instability. This technique creates a double-mattress suture providing a large footprint for the subscapularis and a broader surface area to allow for effective tendon to bone healing. Furthermore, it obviates the need for detaching the subscapularis tendon and avoids the morbidity potentially associated with open procedures. Level of evidence V.

Evaluation and management of posterior shoulder instability

CONTEXT

Posterior shoulder instability is a commonly misdiagnosed disorder in many competitive athletes.

TYPE OF STUDY

Clinical review.

EVIDENCE ACQUISITION

Relevant studies on posterior shoulder instability from 1950 to 2010 in PubMed and Cochrane databases were reviewed.

RESULTS

A total of 107 studies were reviewed.

CONCLUSION

Patients who have undergone at least 6 months of physical therapy and still experience instability symptoms should be considered for surgical stabilization directed at their underlying pathology.

The rationale for an arthroscopic approach to shoulder stabilization

The gold standard of treatment for glenohumeral instability has traditionally been viewed as open shoulder stabilization. With the increased awareness of complex instability patterns and the ability to preoperatively detect concomitant pathology with advanced imaging modalities, an evidence-based shift to an all-arthroscopic approach to shoulder stabilization surgery is occurring. Current data suggest that patients who meet eligibility criteria for arthroscopic stabilization (those without significant bony lesions or significant deformity) can expect equivalent rates of recurrence, better functional outcomes, and less morbidity. Modern arthroscopic techniques using suture anchors and capsular plication have resulted in a significant improvement over previous reports in the orthopaedic literature. An argument is put forth on the benefits of an all-arthroscopic approach to shoulder stabilization in athletes and nonathletes alike based on a review of the current orthopaedic literature comparing the evolved arthroscopic technique with more traditional open methods.

Posterior shoulder instability: current concepts review

PURPOSE

Posterior shoulder instability has been difficult to diagnose and even more challenging to manage. However, it is being diagnosed and treated more frequently, particularly after sports injuries. The purpose of this article is to review literature concerning the management of these pathologies.

METHODS

A literature review was carried out in the main medical databases to evaluate the several studies concerning the open and arthroscopic treatment of posterior shoulder instability.

RESULTS

Because of better awareness of the pathology, better technical investigations, and a better understanding of shoulder biomechanics, more and more mechanical factors that can cause posterior instability have been described. Structural abnormalities can be divided into bony abnormalities and soft-tissue abnormalities. Each group can also be divided into abnormalities caused by trauma (macro- or microtrauma) or congenital. These abnormalities can be treated with non-anatomic and anatomic stability procedures. During the last decades, the latter have been described more frequently, most of them arthroscopically.

CONCLUSION

For surgical treatment to be successful, the instability must be attributable to mechanical factors that can be modified by surgery. Because of better knowledge of the pathology, a more specific surgery can be performed. This lesion-specific surgery has improved clinical results compared to non-anatomic stability procedures, particularly when that surgery has been performed arthroscopically.

Arthroscopic stabilization of posterior shoulder instability

Posterior shoulder instability is a rare and challenging condition with a complex patho-anatomy. The role of arthroscopic repair in the treatment remains poorly defined. The purpose of this study is to evaluate the result of arthroscopic stabilization procedures in patients with posterior shoulder instability. In this case series, we treated eighteen patients (19 shoulders) with posterior shoulder instability with either arthroscopic thermal capsular shrinkage (9 patients), capsulorrhaphy (3) or labral refixation (7). There were eight male and ten female patients with a mean age of 26 years. The study group included unidirectional (6 patients; PI), bi-directional (8; PII) and multidirectional posterior instability (5; MDI). The Rowe-score and DASH-score as well as subjective and objective evaluations of the patients function, range of motion, pain and instability were used as clinical outcome measurements. At a mean follow-up of 50 months, the Rowe-score improved significantly from 46 to 74 (P = 0.005). Four patients (21%) had recurrent instability after arthroscopic treatment (2 with generalized ligamentous laxity; 3 after thermal shrinkage). Analysis of postoperative DASH-scores showed a tendency toward inferior outcomes after thermal shrinkage and in patients with an a-traumatic origin of shoulder instability. We conclude that arthroscopic shoulder stabilization by either labral refixation or capsulorrhaphy is a safe and effective treatment for posterior shoulder instability. Thermal capsular shrinkage however showed poor results and should be abandoned for this indication.

Arthroscopic posterior labral repair in athletes: Outcome analysis at 2-year follow-up

PURPOSE

The purpose of this outcome analysis was to evaluate the clinical presentation of isolated posterior labral tears resulting from athletic injury and to use multiple outcome measurements to evaluate postoperative results after arthroscopic repair with respect to satisfaction, function, and return to sport.

METHODS

Seventy-five consecutive patients injured during athletic activity were treated surgically during the 2-year period from 2005 to 2006 for labral pathologies. Twenty-eight patients were treated for isolated posterior labral tears. Of these, all underwent arthroscopic repair of their tears. The mechanism of injury was trauma to a previously asymptomatic shoulder during sports. The patients' mean age was 21 years, and they were evaluated with American Shoulder and Elbow Surgeons; University of California, Los Angeles; Rowe; and visual analog scale scores, as well as active motion and dynamometric strength testing. Scores and measurements were obtained preoperatively and postoperatively at 3, 6, and 12 months and yearly thereafter.

RESULTS

In our athletic population undergoing surgical management for labral pathology, 37% of patients (28 of 75) were found to have purely posterior labral lesions after an athletic injury. On intraoperative examination, an element of posterior laxity was seen in only 29% of patients with these tears. At 24 months, significant improvements were observed in the American Shoulder and Elbow Surgeons; University of California, Los Angeles; Rowe; and visual analog scale scores. Increases in forward flexion and external rotation strength were also noted. Return to sport was achieved in 26 of 28 patients (93%). A 93% patient satisfaction rate was observed for arthroscopic posterior labral repairs at more than 24 months.

CONCLUSIONS

Our patient-athletes presented with painful, dysfunctional shoulders that inhibited performance in their chosen sport. Arthroscopic evaluation and repair of these posterior labral lesions resulted in 26 of 28 patients (93%) returning to sport and 23 of 28 (82%) returning without any limitations.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Shoulder instability in patients with joint hyperlaxity

Generalized ligamentous hyperlaxity and glenohumeral joint instability are common conditions that exhibit a spectrum of diverse clinical forms and may coexist in the same patient. No single diagnostic test can confirm the presence of these disorders, and a careful clinical assessment is important. Unlike patients with traumatic shoulder instability, patients with hyperlaxity and instability are more likely to experience episodes of recurrent subluxation than they are to have recurrent dislocation. They are more likely to have instability in more than one anatomic plane, and they usually do not have the soft-tissue and osseous lesions associated with traumatic instability. Shoulder symptoms in a patient with hyperlaxity are not always due to instability; other pathological conditions may coexist, with rotator cuff impingement being the most common. Most patients with hyperlaxity have a reduction in instability symptoms after nonoperative treatment, including physical therapy, activity modification, and additional psychological support when necessary. Operative treatment provides reproducibly good results for patients with hyperlaxity who do not respond to a prolonged program of nonoperative measures. Open inferior capsular shift remains the gold standard of operative treatment, although arthroscopic capsular shift and plication procedures are now producing comparable results. Thermal capsulorrhaphy is associated with unacceptably high failure rates and postoperative complications and cannot be recommended as a treatment.

MR arthrographic assessment of suspected posteroinferior labral lesions using flexion, adduction, and internal rotation positioning of the arm: preliminary experience

OBJECTIVE

Imaging the shoulder in the position of flexion, adduction, and internal rotation (FADIR) may be useful in characterizing lesions of the posteroinferior labrum. The purpose of this preliminary study is to illustrate the diagnostic utility of FADIR positioning in the assessment and characterization of posteroinferior labral tears.

MATERIALS AND METHODS

In the FADIR position, the arm is placed across the chest, with the hand on the contralateral shoulder and palm facing outwards. FADIR positioning was performed if there was a subtle or equivocal abnormality of the posteroinferior labrum on conventional MR arthrography sequences. A retrospective review of the charts of 9 people who were imaged using FADIR positioning in addition to routine MR arthrographic sequences of the shoulder was performed. The review included the indication for the study, documentation of presence of clinical posterior instability, and surgical correlation, where available.

RESULTS

In all 9 patients, FADIR positioning helped confirm, exclude, or better characterize a posteroinferior labral abnormality by increasing the diagnostic confidence.

CONCLUSION

Flexion, adduction, and internal rotation positioning appears to be a useful adjunct in evaluating patients with equivocal or subtle posteroinferior labral abnormalities on conventional MR arthrography sequences.

Rehabilitation and functional outcomes in collegiate wrestlers following a posterior shoulder stabilization procedure

STUDY DESIGN

Case series.

CASE DESCRIPTION

Five consecutive collegiate Division I wrestlers, with a mean age of 20.2 years (range, 18-22 years), were treated postsurgical stabilization to address posterior glenohumeral joint instability. All received physical therapy postoperatively, consisting of range-ofmotion, strengthening, and plyometrics exercises, neuromuscular re-education, and sport-specific training. Functional outcome scores using the Penn Shoulder Score questionnaire were recorded at postsurgical initial evaluation and discharge. Isometric shoulder strength, measured with a handheld dynamometer at discharge, was compared with measurements made during preseason screening.

OUTCOMES

Postsurgery, upon initial physical therapy evaluation, scores on the Penn Shoulder Score questionnaire ranged from 37 to 74 out of 100. All 5 wrestlers improved with rehabilitation such that their scores at discharge ranged from 81 to 91 out of 100. Mean external rotation-internal rotation strength ratio for the involved shoulder was 73.5% (range, 55.9%-88.7%) preseason and 80.9% (range, 70.2%-104.1%) postrehabilitation. Four patients were able to return to wrestling over a period of 1 season, with no episodes of reinjury to their surgically repaired shoulder.

DISCUSSION

Current research on posterior glenohumeral instability is limited, due to the relatively rare diagnosis and infrequent need for surgical intervention. Providing a structured physical therapy program following this surgical procedure appeared to have assisted in a return to full functional activities and sports.

LEVEL OF EVIDENCE

Therapy, level 4. J Orthop Sports Phys Ther 2009;39(7):550-559, Epub 24 February 2009. doi:10.2519/jospt.2009.2952.

Arthroscopic management of posterior shoulder instability: diagnosis, indications, and technique

With increased understanding of the different patterns of posterior shoulder instability, diagnostic acumen and successful treatment algorithms have evolved. Improvements in imaging and advancements in arthroscopic surgical techniques have facilitated this progress. In athletic populations, recurrent posterior subluxations (RPSs) are far more common than recurrent or locked posterior dislocations. Conservative and operative management of posterior instability is individualized to meet the demands of its diverse patient population, ranging from post-traumatic instability in contact athletes to RPSs in overhead athletes.