Approach to the treatment of primary anterior shoulder dislocation: A review

Arthroscopic findings of traumatic first-time anterior shoulder instability: a comparison of adolescent versus adult patients

Background

Recurrence rates after first-time shoulder dislocation in young patients are high, especially in their early teens. Only a few studies have arthroscopically investigated the inside of the glenohumeral joint in young patients. Such arthroscopic investigation would help in solving the cause of the greater incidence of recurrent instability in the young population, especially in their early teens.

Methods

Data from 42 patients with first-time anterior shoulder dislocation were retrospectively reviewed. The participants were divided into two groups: those aged 10 to 15 years at the time of the dislocation (adolescent group) and those aged 20- 29 years (adult group). The arthroscopic findings regarding the glenohumeral joint in the adolescent group were assessed and compared to those in the adult group. The intra-articular pathology was examined in all cases and recorded with specific reference to (1) the anterior capsulolabral lesion, (2) Hill-Sachs lesion, (3) labrum-anteroinferior glenohumeral ligament complex, and (4) other concomitant lesions.

Results

Anterior joint laxity was found more in the adolescent group than in the adult group (P = .046). Thirty-six (83%) shoulders had Hill-Sachs lesions: 6 shoulders (60%) in the adolescent group and 30 shoulders (97%) in the adult group, with a significant difference (P < .001).

Conclusion

Pathological findings observed during arthroscopy are more common in the adult group, whereas recurrent instability is more likely in adolescent group.

Biomechanical study of 3D-printed titanium alloy pad for repairing glenoid bone defect

Background: The purpose of this study was to investigate the effect of 3D-printed technology to repair glenoid bone defect on shoulder joint stability. Methods: The shoulder joints of 25 male cadavers were tested. The 3D-printed glenoid pad was designed and fabricated. The specimens were divided into 5 groups. Group A: no bone defect and the structure of the glenoid labrum and joint capsule was intact; Group B: Anterior inferior bone defect of the shoulder glenoid; Group C: a pad with a width of 2 mm was installed; Group D: a pad with a width of 4 mm was installed; Group E: a pad with a width of 6 mm was installed. This study measured the distance the humeral head moved forward at the time of glenohumeral dislocation and the maximum load required to dislocate the shoulder. Results: The shoulder joint stability and humerus displacement was significantly lower in groups B and C compared with group A (p < .05). Compared with group A, the stability of the shoulder joint of group D was significantly improved (p < .05). However, there was no significant difference in humerus displacement between groups D and A (p > .05). In addition, compared with group A, shoulder joint stability was significantly increased and humerus displacement was significantly decreased in group E (p < .05). Conclusion: The 3D-printed technology can be used to make the shoulder glenoid pad to perfectly restore the geometric shape of the shoulder glenoid articular surface. Moreover, the 3D-printed pad is 2 mm larger than the normal glenoid width to restore the initial stability of the shoulder joint.

Austere Diagnosis and Reduction of Anterior Shoulder Dislocations: 10-Year Review of a Ski Patrol-Based Program with Emergency Medical Technicians

INTRODUCTION

Glenohumeral dislocations present a challenging management dilemma in austere settings where patient transport time may be prolonged. Expeditious reduction is preferable, but treatment is commonly expected to take place within a hospital or comparable facility. Through a novel shoulder injury program, professional ski patrollers trained as emergency medical technicians (EMTs) have diagnosed and reduced anterior shoulder dislocations using biomechanical techniques without sedation or analgesia for over 20 y. Summary records have been maintained to track the performance and safety of this program.

METHODS

Five hundred forty-six records of winter sports-related shoulder injuries from 2009-10 to 2019-20 were retrospectively analyzed to determine the assessment performance and dislocation reduction efficacy of EMTs, with the intent of ascertaining whether EMT-trained practitioners can reliably and safely diagnose and reduce anterior shoulder dislocations without premedication in a remote and resource-limited setting.

RESULTS

EMTs identified anterior shoulder dislocations with 98% sensitivity and 96% diagnostic accuracy. The overall success rate of reduction attempts was 86%, or 88% when limited to confirmed anterior dislocations. Two fracture-dislocations and 4 misdiagnoses were manipulated. No instances of iatrogenic harm were identified, and no patients who underwent successful reductions required ambulance transportation.

CONCLUSIONS

With appropriate education and within a structured program, EMT-trained practitioners can reliably and safely diagnose and reduce anterior shoulder dislocations using biomechanical techniques without premedication in remote and resource-limited environments. Implementation of similar programs in austere settings has the potential to improve patient care. Further, using biomechanical reduction techniques may reduce reliance on procedural sedation irrespective of care setting.

Physical Therapy for the Treatment of Shoulder Instability

Shoulder instability is the separation of the humeral head from the glenoid. Injury to the static and dynamic stabilizers can result in instability. Anterior shoulder instability is the predominant form of instability. It is usually a result of trauma. Posterior shoulder instability often presents with an insidious onset of pain. Multidirectional instability of the shoulder is symptomatic laxity in more than one plane of motion. The primary goal of rehabilitation is to restore pain-free mobility, strength, and functioning. Rehabilitation implements range of motion and strengthening exercises to restore proprioceptive control and scapular kinematics.

Glenoid Bone Loss Directly Affects Hill-Sachs Morphology: An Advanced 3-Dimensional Analysis

BACKGROUND

While the glenoid track concept presents a useful prediction for recurrent glenohumeral instability, little is known about the humeral head bony architecture as it relates to glenoid erosion in the setting of bipolar bone loss.

PURPOSE

To (1) qualitatively and quantitatively analyze the interplay between glenoid bone loss (GBL) and Hill-Sachs lesions (HSLs) in a cohort of patients with anterior instability using 3-dimensional imaging software and (2) assess the relationships between GBL and HSL characteristics.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients were identified who had anterior shoulder instability with a minimum 5% GBL and evidence of HSL confirmed on computed tomography. Unilateral 3-dimensional models of the ipsilateral proximal humeral head and en face sagittal oblique view of the glenoid were reconstructed using MIMICS software (Materialise NV). GBL surface area, width, defect length, and glenoid track width were quantified. The volume, surface area, width, and depth of identified HSLs were quantified with their location (medial, superior, and inferior extent) on the humeral head. Severity of GBL was defined as percentage glenoid bone surface area loss and categorized as low grade (5%-10%), moderate grade (>10% to 20%), high grade (>20% to 30%), and extensive (>30%). Analysis of variance was then computed to determine significance (P < .05) between severity of GBL and associated HSL parameters.

RESULTS

In total, 100 patients met inclusion criteria (mean age, 27.9 years; range, 18-43 years), which included 58 right shoulders and 42 left shoulders (84 male, 16 female). Among groups, there were 32 patients with low-grade GBL (mean GBL = 6.1%), 38 with moderate grade (mean GBL = 16.2%), 17 with high grade (mean GBL = 23.7%), and 13 with extensive (mean GBL = 34.0%), with an overall mean GBL of 18.1% (range, 5%-39%). Patients with 5%-10% GBL had significantly narrower HSLs (average and maximum width; P < .03) and deeper HSLs (average depth; P = .002) as compared with all other GBL groups, while greater GBL was associated with wider and shallower HSLs. GBL width, percentage width loss, defect length, and glenoid track width all significantly differed across the 4 GBL groups (P < .05).

CONCLUSION

HSLs had significantly different morphological characteristics depending on the severity of GBL, indicating that GBL was directly related to the characteristics of HSLs. Patients presenting with smaller glenoid defects had significantly narrower and deeper HSLs with less humeral head surface area loss, while greater GBL was associated with wider and shallower HSLs.

Incidence of Re-Dislocation/Instability After Arthroscopic Bankart Repair: Analysis via Telephone Interviews

INTRODUCTION

Current advances in arthroscopic surgery have led to good outcomes for arthroscopic Bankart repair (ABR) for recurrent anterior shoulder dislocation. However, recent studies have reported recurrence rates of 4%-19% after ABR. In our survey conducted from February 2002 to December 2010, the post-ABR re-dislocation rate was 8.8%. In 2011, we began performing the ABR with open Bristow (B) procedure or Remplissage (R) procedure in patients with large glenoid or humeral head bone defects and in patients who play collision sports. Therefore, the present study is the second series evaluating the incidence of re-dislocation and instability after recurrent anterior shoulder dislocation.

METHOD

Surgery was performed for 84 cases of shoulder instability from January 2011 to August 2017. After excluding 7 open surgeries, 6 reoperations, and 2 patients with multidirectional instability, telephone interviews were conducted with 69 patients. The average follow-up duration was 46.9 months (range, 13-92 months).

RESULT

ABR alone was performed 61 patients; the B procedure was added for 3 patients, and the R procedure was added for 5 patients. Telephone interviews were conducted with 61 patients. There were no cases of re-dislocation or reoperation. Four patients who underwent only ABR experienced postoperative instability, but not to the extent that their daily lives were affected.

CONCLUSION

This study showed that the addition of R or B technique to ABR for recurrent anterior shoulder dislocation resulted in a 0% re-dislocation rate.

Differences in Outcomes Between Anterior and Posterior Shoulder Instability After Arthroscopic Bankart Repair: A Systematic Review and Meta-analysis

Background:

The glenohumeral joint is one of the most frequently dislocated joints in the body, particularly in young, active adults.

Purpose:

To conduct a systematic review and meta-analysis to evaluate and compare outcomes between anterior versus posterior shoulder instability.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was performed using the PubMed, Cochrane Library, and MEDLINE databases (from inception to September 2019) according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they were published in the English language, contained outcomes after anterior or posterior shoulder instability, had at least 1 year of follow-up, and included arthroscopic soft tissue labral repair of either anterior or posterior instability. Outcomes including return-to-sport (RTS) rate, postoperative instability rate, and pre- and postoperative American Shoulder and Elbow Surgeons (ASES) scores were recorded and analyzed.

Results:

Overall, 39 studies were included (2077 patients; 1716 male patients and 361 female patients). Patients with anterior instability had a mean age of 23.45 ± 5.40 years (range, 11-72 years), while patients with posterior instability had a mean age of 23.08 ± 8.41 years (range, 13-61 years). The percentage of male patients with anterior instability was significantly higher than that of female patients (odds ratio [OR], 1.36; 95% CI, 1.04-1.77; P = .021). Compared with patients with posterior instability, those with anterior instability were significantly more likely to RTS (OR, 2.31; 95% CI, 1.76-3.04; P < .001), and they were significantly more likely to have postoperative instability (OR, 1.53; 95% CI, 1.07-2.23; P = .018). Patients with anterior instability also had significantly higher ASES scores than those with posterior instability (difference in means, 6.74; 95% CI, 4.71-8.77; P < .001). There were no significant differences found in postoperative complications between the anterior group (11 complications; 1.8%) and the posterior group (3 complications; 1.6%) (OR, 1.12; 95% CI, 0.29-6.30; P = .999).

Conclusion:

Patients with anterior shoulder instability had higher RTS rates but were more likely to have postoperative instability compared with posterior instability patients. Overall, male patients were significantly more likely to have anterior shoulder instability, while female patients were significantly more likely to have posterior shoulder instability.

Arthroscopic nomenclature of capsulolabral appearances in anterior shoulder dislocation

Objectives

To study the intraoperative morphology of the glenoid labrum and capsule in recurrent shoulder dislocation and to study the relationship between the number of dislocations and the changes in the glenoid and labrum.

Methods

Over a period of 18 months, 108 patients with traumatic anterior dislocations were included in the study, of which 102 men and 6 women with mean age of 33.4yrs range from 18 to 45. The patients with bony bankart, other labral lesions, ligamentous laxity, SLAP tear were excluded from the study. All the patients underwent arthroscopic bankart repair. We have classified the morphology of labrum and capsule on their appearance intraoperatively. Labrum is named as Normal, Desiccated or Shredded and Capsule as Normal or Damaged.

Results

Six varieties of appearances were observed. Namely, Normal capsule and Normal labrum (NN), Normal capsule and Desiccated labrum (ND), Normal capsule and Shredded labrum (NS), Damaged capsule and Normal labrum (DN), Damaged capsule and Desiccated labrum(DD), Damaged capsule and Shredded labrum(DS). Among them, DD (33.3%) and DS (29.6%) variety had highest number of dislocations suggesting the labrum and capsule lose normal anatomy with more recurrence of dislocations.

Conclusion

These findings support that reproducing normal anatomy after surgical repair is possible when the intervention is done sooner than later.

Level of evidence

III.

Traumatic Primary Anterior Glenohumeral Joint Dislocation in Sports: A Systematic Review of Operative versus Nonoperative Management

Anterior shoulder (glenohumeral joint [GHJ]) dislocations are relatively common injuries in sports. Previous studies have evaluated clinical outcomes of operative and nonoperative management for primary traumatic anterior GHJ dislocations. The purpose of this study was to systematically review the literature in an effort to provide a thorough analysis of patients after undergoing closed reduction of a traumatic anterior GHJ dislocation, particularly among the athletic population. Two independent reviewers performed a comprehensive search of PubMed and the Cochrane Library through February 23, 2020. Unfortunately, the quantity and quality of published articles on this subject is very limited. In many studies, younger age (between 21 and 30 years) was associated with greater risk for recurrence of GHJ dislocations. Twelve studies (total N = 753) directly compared outcomes of operative versus nonoperative management. It seems that operative management significantly reduces recurrence rates with patients treated operatively among the young and active population. Operative management should be considered as a treatment option for young and athletic patients presenting with a first-time anterior GHJ dislocation.

Comprehensive Arthroscopic Shoulder Stabilization in the Lateral Decubitus Position

Arthroscopic shoulder stabilization offers a safe and effective means for restoring glenohumeral mechanics in the setting of shoulder instability. Modern arthroscopic techniques have allowed improved access and efficiency when treating patients with shoulder instability. However, access to certain areas of the labrum and the creation of safe accessory portals can still prove difficult for the arthroscopic surgeon. Currently, there is debate as to the ideal patient position, portal location, equipment, and technique for addressing anterior-inferior labral pathology. The following article presents a safe and effective approach to accessing the labrum for treatment of shoulder instability in the lateral decubitus position. In addition, this paper highlights the use of accessory portals, including a percutaneous "7-o'clock" portal for suture anchor placement, along with multiple types of suture anchor and suture shuttling techniques.

[Experimental study on reconstruction of anterior labrum of shoulder joint by chemical extraction of allogeneic tendon and allogeneic chondrocytes]

OBJECTIVE

To study the effect of chemical extraction of allogeneic tendon and allogeneic chondrocytes for reconstruction of anterior labrum of shoulder joint in rabbits.

METHODS

The body weight of 45 adult New Zealand white rabbits ranged from 2.5 to 3.0 kg. The Achilles tendons of 15 rabbits were taken and the allogeneic tendons were prepared by chemical extraction with antigen inactivation. The extracted tendons were compared with untreated tendons by HE and Masson stainings. Chondrocytes were isolated and cultured by trypsin method and identified by immunohistochemical staining of collagen type Ⅱ. The remaining 30 rabbits were used to prepare the model of anterior labrum defect of shoulder joint. After the allogeneic tendon was transplanted to the damaged labrum, the rabbits was randomly divided into two groups (15 in each group). In group A, the allogeneic chondrocytes were injected into the joint immediately after transplantation, while in group B, no treatment was made. At 4, 6, and 8 weeks after operation, 5 transplanted tendons of each group were taken. After general observation, HE staining was used to observe the number of nuclei, Masson staining was used to observe the expression of collagen fibers in muscle fiber tissues, and AB staining was used to detect the glycosaminoglycan level after transplantation, to evaluate the cell growth in the tissues of the two groups of allogeneic tendon.

RESULTS

By HE and Masson stainings, the allogeneic tendon antigen prepared by chemical extraction method was inactivated and the fibrous tissue structure was intact; collagen type Ⅱ immunohisto-chemistry staining showed that the cultured cells were chondrocytes. After tendon transplantation, the content of glycosaminoglycan in group A was significantly higher than that in group B ( P<0.05). At 6 weeks after operation, HE staining showed that the nuclear in tendon tissue of group A was significantly more than that of group B ( t=20.043, P=0.000). Masson staining showed that the number of nuclei in tendon tissue of group A was significantly increased, the muscle fibers and collagen fibers were interlaced, the tissue structure was more compact, and the tendon tissue was mainly blue stained; while the number of nuclei in group B was less, mainly collagen fibers of the original graft.

CONCLUSION

The allogeneic tendon inactivated by chemical extraction can be used to reconstruct the defect of anterior labrum of shoulder joint in rabbits, and the combination of allogeneic chondrocytes can promote the healing of tendon transplantation.

Immobilization in external rotation versus internal rotation after shoulder dislocation: A meta-analysis of randomized controlled trials

INTRODUCTION

Recurrence rates after primary traumatic shoulder dislocation are distinctly high. Whether the early external immobilization (ER) is better than the internal immobilization (IR) is still controversial.

HYPOTHESIS

To perform a systematic review of randomized clinical trials (RCTs) that assessed the ability of external immobilization to reduce the recurrence in patients with primary anterior shoulder instability.

MATERIAL AND METHOD

As with the original review, we used the search strategies recommended by the Cochrane Back Review Group for the identification of RCTs. Thirteen RCTs were included in the systematic review, and 11 studies were included in the quantitative synthesis.

RESULT

A total of 1042 participants with primary shoulder dislocation were involved. The meta-analysis of 11 trials revealed that ER therapy leading to less recurrence rates than participants treated with IR therapy (RR=0.55; 95%CI: 0.36 to 0.82; Z=2.88; p=0.004), and less complications (RR=0.6; 95%CI: 0.39 to 0.92; Z=2.33; p=0.02) from the 5 independent trials. The meta-analysis of three trials revealed that there are not statistically significant in compliance rate (RR=1.08; 95%CI: 0.89 to 1.29; Z=0.78; p=0.44). The GRADE level of evidence is high for adverse events, but moderate for recurrence rate and Compliance rate. The Begg test showed that no significant publication bias was detected (p=0.062).

DISCUSSION

This meta-analysis suggests that external immobilization is recommended to reduce the recurrence rate and prevent complications.

LEVEL OF PROOF

II, low-powered systematic review and meta-analysis (systematic review, meta-analysis).

Allogenic Tendon-Autologous Cartilage Cells Transplantation Enhances Adhesive/Growth Ability and Promotes Chondrogenesis in a Rabbit Model of Glenoid Labrum Damage

Background

Glenoid labrum injury of the shoulder commonly occurs in athletes, especially those who perform throwing motions. This study investigated the effects of the established allogenic tendon-autologous cartilage cells reconstruction approach in a rabbit model of glenoid labrum damage.

Material/Methods

The allogenic tendons were isolated and extracted using the chemical extraction method. Cartilage cells were isolated from New Zealand rabbits and identified by detecting type II collagenase. The allogenic tendon-autologous cartilage cells were transplanted to the damaged glenoid labrum. HE staining was used to observe inflammatory cells, Masson staining was used to observe muscle fibers, and scanning electron microscopy (SEM) was used to assess antigenicity of tendon tissues. PSA and AB staining were used to examine neutral protein mucopolysaccharide and acidic protein mucopolysaccharide, respectively. We assessed cartilage cell growth in autologous cartilage cells combined with allogenic tendon transplanted tissues.

Results

Allogenic tendons were well prepared using chemical extraction method due to use of HE staining, Masson staining, and SEM. TGF-β1 treatment induced cartilage cell formation and triggered expression of acidic and neutral protein mucopolysaccharides. HE staining, Masson staining, PAS staining, and AB staining methods showed that autologous cartilage cells combined with allogenic tendon transplanted tissues had better growth of cartilage cells.

Conclusions

This study establishes the allogenic tendon-autologous cartilage cells reconstruction and transplantation approach and illustrated higher adhesive ability and growth ability, and better chondrogenesis in a rabbit model of glenoid labrum damage.

Does the Beighton Score Correlate With Specific Measures of Shoulder Joint Laxity?

Background

Evaluation of shoulder joint laxity is an important component of the shoulder examination, especially in the setting of shoulder instability. Measures of generalized joint laxity, particularly the Beighton score, are often recorded and used to help make management decisions in these cases. However, no evidence is available to show that the Beighton score corresponds to specific measures of shoulder joint laxity.

Purpose

To assess the correlation between the Beighton score and validated measures of shoulder joint laxity.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A total of 160 participants (age range, 16-35 years) with no history of shoulder joint abnormality were examined. The Beighton score, glenohumeral external rotation (standing and lying), glenohumeral abduction, and the sulcus sign were recorded. The relationship between the Beighton score and each measure of shoulder joint laxity was assessed.

Results

A high proportion of participants (34%) had a Beighton score of 4 or higher. Rates of positive shoulder laxity tests were lower (11%-19%). A positive Beighton score was a poor predictor of abnormal shoulder laxity, with low sensitivity (range, 0.40-0.48) and low positive predictive values (range, 0.13-0.31). Spearman correlation coefficients demonstrated poor correlation between the Beighton score and all measures of shoulder joint laxity when assessed as continuous variables (range, 0.29-0.45).

Conclusion

The Beighton score has poor correlation with specific measures of shoulder joint laxity and should not be considered equivalent to these tests as a method of clinical assessment.