Traumatic Posterior Instability Research Articles

Location and size of the reverse Hill-Sachs lesion in patients with traumatic posterior shoulder instability

BackgroundIn patients with traumatic posterior shoulder instability, little is known about the precise location and size of the reverse Hill-Sachs lesion. MethodsForty-nine shoulders of 47 patients with traumatic posterior instability were included in this study based on the following inclusion criteria: 1) a primary or recurrent traumatic posterior shoulder dislocation, and 2) the initial event was caused by trauma. Patients were excluded if they had: 1) no history of trauma, 2) prior shoulder surgery, 3) no CT examination, or 4) seizure cases. Three-dimensional images of the humerus reconstructed from CT images were reviewed using an image analysis software. The location and size of the reverse Hill-Sachs lesion were measured and described on a clock face on the humeral head. ResultsThe reverse Hill-Sachs lesion was observed in 25 of 49 shoulders (51%). The reverse Hill-Sachs lesions were located between 1:37 and 2:48. The depth of the reverse Hill-Sachs lesion (mean ± SD) was 5.8 ± 2.2 mm. The extent of the reverse Hill-Sachs lesion was 35° ± 12°. The average orientation of the reverse Hill-Sachs lesion, represented by an angle measured from the 12 o'clock position, was 64° ± 12° and pointing towards 2:09 on a clock face. Length and width of reverse Hill-Sachs lesions were 9.7 ± 4.7 mm, 11.1 ± 3.6 mm, respectively. ConclusionThe reverse Hill-Sachs lesion was a semicircular compression fracture located on the anteromedial aspect of the humeral head. Compared with shoulders with anterior shoulder instability, the humeral defect was smaller and located more inferiorly in shoulders with posterior instability.

Clinical Characteristics and Surgical Outcomes for Collision Athletes with Traumatic Posterior Instability.

Diagnosis and treatment of traumatic posterior instability of the shoulder have not been described in detail. The author investigated surgical outcomes for traumatic posterior shoulder joint instability in collision athletes. The author surgically treated patients with a diagnosis of traumatic shoulder joint instability and investigated those that had been followed up for >2 years after surgery. Seven shoulders in six collision athletes with a history of traumatic injury were examined. All cases were negative for the general laxity sign and positive for the posterior jerk test; five shoulders showed positive anterior apprehension. Posterior glenoid osseous defects were found in three shoulders, and one shoulder injury involved anterior and posterior osseous lesions. As surgical treatment, one posterior capsulolabral lesion, two posterior osseous lesions, and three combined anterior and posterior capsulolabral lesions were repaired arthroscopically. In a patient with a combined anterior and posterior osseous lesion, the Bristow procedure was perfromed after arthroscopic osseous repair. Patients returned to competition at an average of 6.8 months after surgery. One patient developed anterior subluxation at 7 months, and another exhibited posterior re-dislocation at 8 months after returning to competition. Traumatic posterior instability in collision athletes often involves glenoid osseous lesions and is frequently accompanied by anterior apprehension and lesions. Although collision athletes can return to play after arthroscopic repair, such activity is associated with a risk of re-dislocation.

Risk Factors for Intra-Articular Bone and Cartilage Lesions in Patients Undergoing Surgical Treatment for Posterior Instability

Objectives:Patients with posterior shoulder instability often present with significant differences in history of injury and complaints compared to anterior instability that can lead to challenges in diagnosis and treatment. These patients may have bone and cartilage lesions in addition to caspulolabral injuries, though the risk factors for these intra-articular lesions are unclear. The purpose of this study was to describe intraoperative incidence of glenohumeral bone and cartilage lesions in a cohort of patients undergoing primary posterior stabilization using data from a prospectively collected, multicenter shoulder instability cohort. We hypothesized that patients with traumatic posterior instability with greater number of instability events would have higher rate of bone and cartilage injuries compared to those without fewer instability episodes.Methods:Data from the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Group instability patient cohort was utilized for this study. This is a multi-center study encompassing a prospective evaluation of patients ages 12 to 99 years of age undergoing primary surgical treatment for shoulder instability by 24 orthopedic surgeons at 11 sites in the United States. Demographic data and specifics regarding the patient’s instability history were recorded, including patient age, sex, body mass index (BMI), history of smoking, and Beighton score. The number of instability events was classified as 0, 1, 2 to 5, or more than 5. The duration of symptoms was classified as <1 month, 1-3 months, 4-6 months, 7-12 months, or greater than 1 year. The glenohumeral joint was evaluated by the treating surgeon at the time of surgical treatment for bone and cartilage injuries, and patients were classified as having a bone or cartilage lesion (BCL) if there was any grade 3 or 4 glenoid or humeral cartilage lesion, reverse Hill-Sachs lesion, bony Bankart lesion, or glenoid bone loss. The effects of number of instability events on the presence of BCLs was investigated using Fisher’s exact tests. Multivariate analysis using logistic regression modeling was performed to investigate the independent contributions of demographic variables and injury-specific variables to the likelihood of having a BCL. Significance was defined as p<0.05.Results:There were 271 patients identified for analysis. Bone and cartilage lesions were identified in 59 patients (21.8%) at the time of surgical treatment (Table 1). The most common lesion was a glenoid cartilage injury, which was identified in 28 patients (10.3%). Patients with BCLs were significantly older and had significantly higher BMI relative to patients without BCLs (Table 2). There was a significant difference between the number of instability events and the presence of BCLs (p = 0.035), with the highest rate observed in patients with 2-5 instability events (33.9%) (Figure 1). Through multivariate logistic regression modeling, increasing age (p=0.002), increasing BMI (p=0.012), and 2 to 5 reported instability events (p=0.001) were significant independent predictors of the presence of BCLs.Conclusion:Bone and cartilage lesions are seen significantly more frequently with increasing patient age, increasing BMI, and patients with 2-5 instability events. Early surgical stabilization for posterior instability may be considered to potentially limit the extent of associated intra-articular injury.Table 1.Frequency of Bone and Cartilage Lesions Identified in Patients Undergoing Primary Surgery for Posterior InstabilityIntra-Articular Lesion N % Glenoid cartilage injury*2810.3%Humeral cartilage injury*207.4%Reverse Hill-Sachs165.9%Glenoid bone loss114.1%Bony Bankart83.0%Any bone or cartilage lesion5921.8%*Indicates Outerbridge Grade 3 or 4 lesionsTable 2.Comparison of Patients With and Without Bone and Cartilage Lesions No Bone/Cartilage Lesion (N = 212) Bone/Cartilage Lesion (N = 59) Mean or N Standard Deviation or % Mean or N Standard Deviation or % P Value Age (Years)22.87.726.19.60.025Body Mass Index (kg/)26.34.628.65.20.0014Male Sex (N)17381.6%5084.8%0.70Smoker (N)73.3%46.8%0.26Hyperlax (Beighton >4)5224.5%915.3%0.16Pre-Operative Kerlan-Jobe Score49.321.842.418.30.094Pre-Operative WOSI Score43.618.438.917.70.11Pre-Operative SAS13.04.514.14.20.13WOSI: Western Ontario Shoulder Instability; SAS: Shoulder Activity ScoreFigure 1.

Anterior buttress plate is successful for treating posterior sterno-clavicular dislocation.

Traumatic posterior instability of the sternoclavicular joint is a potentially life-threatening injury. In contrast to the low incidence there is a plethora of different strategies to treat this lesion. It was the objective of this retrospective analysis to evaluate and further develop current strategies. In this retrospective analysis all posterior dislocations that were diagnosed and treated between 2011 and 2018 were included. In this 7year period, eight male patients (median age 32years) were operated. Three patients were not diagnosed at the primary institution and were referred later. Five patients were treated with an anterior buttress plate with clavicular stabilisation only. One patient was stabilized with a temporary sternoclavicular arthrodesis. Two patients were operated using an autologous tendon graft. All of the patients underwent an immediate postoperative CT-scan that documented the anatomical articulation. All patients treated with a plate underwent implant removal. A final CT examination after removal documented the maintenance of the anatomic alignment. The buttress plate technique with clavicular screw fixation is a sufficient treatment to restore and preserve a normal sternoclavicular alignment. The technique finds its indication in unidirectional posterior instability. IV.

Posterior Shoulder Instability in Athletes.

Posterior instability represents up to 10% of all cases of shoulder instability1. In athletes, posterior instability can result from a single traumatic injury, repetitive microtrauma, or, rarely, atraumatic instability. The demands on the athlete’s shoulder, especially in contact or overhead throwing sports, can be dramatic, and, as a result, the managing orthopaedic surgeon must understand the complexities of such an injury complex. Participation in contact sports may result in an increased risk for the development of traumatic posterior instability. In overhead athletes, posterior instability can result from repetitive microtrauma sustained from an early age, which can be further exacerbated with the increase in year-round play. ### Static Stabilizers The static stabilizers of the glenohumeral joint include the glenoid and the humeral head, the capsulolabral complex, the articular surface, and the glenohumeral ligaments. Anatomic alterations of the retroversion of the osseous and chondrolabral portions of the glenoid have been shown to be associated with posterior shoulder instability2. Cadaveric studies of …

Paper 32: Posterior Traumatic Shoulder Instability in Athletes

The posterior shoulder instability is not so frequent but often as a part of the multidirectional instability. In these cases conservative treatment provides good results. In cases of trauma associated with posterior labral lesion, isolated posterior instability can occur, and the surgical treatment may be necessary. Evaluate the results of arthroscopic treatment for traumatic posterior shoulder instability. 21 shoulders/20 patients with traumatic posterior instability of the shoulder were treated arthroscopically. The mean age was 29.38 years (20-53), two patients were females and 18 males. All patients were involved in sports activities. The main complaint was the sensation of pain and giving way of the shoulder during sports activity. All patients had posterior labram injuries confirmed by MRI. The surgery was performed after failure of conservative treatment for three months. The patients underwent arthroscopic treatment on beach chair. The rehabilitation program consisted of postoperative immobilization for 3 weeks in sling in neutral rotation followed by physiotherapy. The return to sport was allowed after 5 months. We used an average of 2.76 anchors (2-4) for repair. The average follow-up was 28.47 months (12-70). There was improvement in symptoms of pain and feeling of instability in all patients. We found limited external rotation of 5 degrees in two patients, and 10 degrees in two other patients. One of the patient (4.76%) with 10 degrees of external rotation defict presented light sports limitations (Rowe Score-90). All the others patients(95.24%) returned to the sport without limitations. The arthroscopic treatment for traumatic posterior shoulder instability offers satisfactory results in the majority of cases (95.24%), with improvement of symptoms and allowing the return to activities. The limitation of external rotation (less than 10 degress) does not cause significant functional activities deficits.

Posterior bony humeral avulsion of glenohumeral ligament with reverse bony Bankart lesion

Recurrent, posterior glenohumeral joint instability is uncommon. Posterior capsulolabral abnormalities, although well described in the literature, are less common than their anterior counterparts and make up roughly 2-5% of all shoulder instability. Previous authors have reported cases of posterior humeral avulsion of the glenohumeral ligament (PHAGL) and a combined posterior Bankart lesion and PHAGL associated with posterior instability. To our knowledge, there has been no reported case of a combined reverse bony Bankart and a posterior bony HAGL injury. We present a case of traumatic posterior instability as a result of a combined posterior bony humeral avulsion of the glenohumeral ligament (PBHAGL) and a posterior bony Bankart lesion.

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Introduction: The impact of posterior instability on the athletic shoulder can be functionally significant and disabling. Open posterior reconstruction has been considered the standard of treatment for this problem. The purpose of this report was to assess the functional outcomes in athletes treated by arthroscopic repair for traumatic posterior instability. Methods: This is a retrospective review of 16 athletes (average age 21.6 years) who opted for arthroscopic repair of traumatic posterior instability of the shoulder between 2001 and 2004.

Combined Posterior Bankart Lesion and Posterior Humeral Avulsion of the Glenohumeral Ligaments Associated With Recurrent Posterior Shoulder Instability

Recurrent posterior glenohumeral instability is uncommon and is often misdiagnosed. Damage to the posterior capsule, posteroinferior glenohumeral ligament, and posterior labrum have all been implicated as sources of traumatic posterior instability. We describe a case of traumatic recurrent posterior instability resulting from a posterior Bankart lesion accompanied by posterior humeral avulsion of the glenohumeral ligaments. The Bankart lesion was repaired using a single arthroscopic suture anchor at the glenoid articular margin. The posterior humeral avulsion of the glenohumeral ligaments was addressed with 3 suture anchors placed at the capsular origin at the posterior humeral head. Using these anchors, the posterior capsule was advanced laterally and superiorly for a secure repair. Arthroscopic anatomic reconstruction of both lesions resulted in an excellent clinical outcome.

Posterior Dislocation in a Voluntary Subluxator

Posterior instability of the shoulder is an uncommon occurrence. Its etiology has been classified as traumatic or atraumatic and its type as voluntary (individual can subluxate the shoulder posteriorly) or involuntary. Typically, patients with posterior voluntary instability do not have a history of trauma, can be treated successfully with physical therapy; and undergo surgery if the instability becomes symptomatic or develops an involuntary component. We present a patient with voluntary posterior subluxation who developed a symptomatic posterior instability after a traumatic event. This patient was unable to return to his preinjury function despite nonoperative interventions, including rehabilitation, and required operative treatment of his posterior labrum lesion. This patient had a rare combination of voluntary, atraumatic instability that coexisted with traumatic posterior shoulder instability. This case emphasizes the importance of recognizing this constellation of instability patterns and documents that traumatic posterior instability, even in the presence of preexisting voluntary posterior subluxations, may require operative intervention in young, active individuals.

Management of Posterior Glenohumeral Instability With Large Humeral Head Defects

Traumatic posterior instability may occasionally cause a large osteochondral lesion when the anterior humeral head is compressed against the posterior glenoid rim. This is termed a reverse Hill–Sachs lesion. Such osteochondral defects may be very large in the case of chronic locked dislocations. Even in acute posterior disclocations, closed reduction may be difficult when the humeral head is locked posteriorly over the glenoid. In such cases closed or open reduction under general anesthesia with muscle relaxation may be necessary. In cases where the anterior humeral head defect is large, reconstruction may be necessary to maintain stability. Management must be tailored to the individual patient and depends on several factors, which include the size of the defect, the duration of the dislocation, the quality of the bone, the status of the articular cartilage, and the patient’s overall health. Treatment options include skillful neglect, subscapularis-lesser tuberosity transfer into the humeral head defect, disimpaction and bone grafting, allograft reconstruction of the humeral articular surface, and arthroplasty.

Shoulder Pain

0411 HISTORY: A 17 year old male who was captain of his high school wrestling team sustained an injury to his right, dominant shoulder during a match. During a take down, his arm was flexed and forcibly driven posteriorly. He felt a “pop” in his shoulder with pain in his shoulder on the posterior aspect. He finished the match but was unable to wrestle thereafter. He sought evaluation for his shoulder pain, 4 weeks later. He had no previous injuries to that shoulder but he says that he could slide both shoulders in and out of the socket since he was a child. He did not have any complaints of parasthesias or weakness. He did complain of pain in the shoulder at rest and a sense of instability with motion. He did not have a history of connective tissue disorders or of systemic illnesses. PHYSICAL EXAMINATION: Normal appearing male in no acute distress. He had no deformity, atrophy or winging. He had full range of motion in all directions equal to the other extremity. He was entirely neurovascularly intact for sensory testing and muscle strength testing. He had a positive Neer and Hawkins impingement signs with diffuse pain in the shoulder. He had pain with both an anterior and posterior apprehension signs but no sense of instability. On his unaffected side he could demonstrate a posterior subluxation with his arm down which he could reduce easily using his own muscles. He could not demonstrate a subluxation on the effected side due to pain. Laxity testing with the patient supine using a posterior drawer revealed that his shoulders could be subluxated posteriorly and would stay out (Hawkins grade III). He was a grade II Hawkins with an anterior drawer with a grade II sulcus sign bilaterally. He met criteria for generalized ligamentous laxity. DIFFERENTIAL DIAGNOSIS: Voluntary shoulder instability Traumatic posterior instability Superior labrum tear (SLAP) Multidirectional instability Connective tissue disorder. TEST AND RESULTS: Plain radiographs (anterior-posterior and axillary radiographs): normal MRI of the shoulder with gadolinium arthrogram: posterior Bankart 3. Diagnostic arthroscopy: posterior Bankart lesion; posterior glenoid erosion FINAL WORKING DIAGNOSIS: Acute, traumatic posterior dislocation superimposed upon previous voluntary posterior instability TREATMENT AND OUTCOMES: Open repair of posterior Bankart lesion Brace in external rotation 6 weeks with finger, wrist and elbow motion Physical therapy for motion and strengthening according to protocol Gradual return to sports and wrestling with no difficulty over 6 months

Arthroscopic Shoulder Capsulorrhaphy Using Metal Staples

Staple capsulorrhaphy on the shoulder using a metal staple for traumatic anterior instability has the advantages of increased diagnostic accuracy, microdebridement of the pathology, accurate assessment of the glenohumeral ligament pathology, and selective repair of the ligament pathology. Although the same advantages should apply to staple capsulorrhaphy for traumatic posterior instability, our experience remains very limited. Staple capsulorrhaphy on the shoulder has multiple disadvantages, including being technically difficult with a slow learning curve, not being applicable to all unstable shoulders, an average failure rate of 12% that may be related to inadequate postoperative immobilization, no extra-articular reinforcement, and the use of a metal implant that may need to be removed at a second operation. Staple capsulorrhaphy is currently performed for traumatic anterior instability in the shoulder, with a selected repair of the pathology using a single, well-placed staple and prolonged postoperative immobilization. The design of the staple affords a simpler insertion technique than rivets, screws, and intra-articular sutures. The advent of a biodegradable staple should eliminate inherent problems of metal implants while preserving the advantages of this method.