Geometry of the proximal humeral articular surface in young children: a study to define normal and analyze the dysplasia due to brachial plexus birth palsy

Glenohumeral morphological predictors of recurrent shoulder instability following arthroscopic Bankart repair

PURPOSE

The purpose of this study was to evaluate glenohumeral morphological features on a magnetic resonance arthrogram (MRA) to determine risk factors for recurrence of anterior shoulder instability following arthroscopic Bankart repair (ABR).

METHODS

A retrospective review of patients who underwent ABR between 2012 and 2017 was performed to identify patients who had recurrence of instability following stabilisation (Group 1). These were pair-matched in a 2:1 ratio for age, gender and sport with a control (Group 2) who underwent ABR without recurrence. Preoperative MRAs were evaluated for risk factors for recurrence, with glenoid bone loss and Hill-Sachs lesions also measured. Multilinear and multilogistic regression models were used to evaluate factors affecting recurrence.

RESULTS

Overall, 72 patients were included in this study, including 48 patients without recurrence and 24 patients with recurrent instability. There was a significant difference between the two groups in mean glenoid bone loss (Group 1: 7.3% vs. Group 2: 5.7%, p < 0.0001) and the rate of off-track Hill-Sachs lesions (Group 1: 20.8% vs. Group 2: 0%, p = 0.0003). Of the variables analysed in logistic regression, increased glenoid anteversion (p = 0.02), acromioclavicular (AC) degeneration (p = 0.03) and increased Hill-Sachs width were associated with increased risk of failure. Increased chondral version (p = 0.01) and humeral head diameter in the anteriorposterior view were found to be protective and associated with a greater likelihood of success.

CONCLUSION

Glenoid anteversion was a risk factor for recurrent instability, whereas increased chondral version and humeral head diameter were associated with higher rates of success following ABR. Glenoid bone loss, presence of an off-track Hill-Sachs lesion, increased Hill-Sachs width and AC degeneration were also associated with failure. These findings should be used by surgeons to stratify risk for recurrence following ABR.

LEVEL OF EVIDENCE

Level III.

Assessment of the relationship between Brachial Plexus Profile activity short form scores and modified Mallet scores

INTRODUCTION

This study aims to assess the relationship between the modified Mallet classification and the Brachial Plexus Profile activity short form (BP-PRO activity SF). The therapist or surgeon classifies upper extremity movement for the modified Mallet classification, while the BP-PRO assesses parents' perceptions of difficulty performing activities.

PURPOSE

To provide a deeper understanding of the relationship of functional and perceived outcome measurements.

STUDY DESIGN

Prospective, correlational design.

METHODS

Eighty children with brachial plexus birth injuries were evaluated using the modified Mallet classification, while parents simultaneously answered the BP-PRO activity SF questions. All patients had undergone one of three surgical interventions to improve shoulder function. The relationship between the two measures, patient injury levels, and surgical histories were assessed.

RESULTS

The average modified Mallet scores and BP-PRO activity SF scores weakly correlated (r = 0.312, P = .005) and both measures differentiated between C5-6 and C5-7 injury levels (P = .03 and P = .02, respectively). Conversely, the modified Mallet scores could differentiate between the three surgical groups (F = 8.2, P < .001), while the BP-PRO activity SF could not (P = .54).

CONCLUSION

The results suggest that these tools measure different aspects of patient outcomes. The Mallet classification may be more focused on shoulder motion than the BP-PRO activity SF. Additional questions that specifically require shoulder function could be incorporated into the BP-PRO activity SF to improve understanding of patient/parent perceptions of shoulder function for children with brachial plexus injuries. Clinicians should be aware of the strengths, weaknesses, and limitations of each outcome assessment tool for appropriate use and interpretation of results.

The outcome of soft-tissue release and tendon transfer in shoulders with brachial plexus birth palsy

Background

Shoulder involvement in brachial plexus birth palsy is common, and the adduction, internal rotation contracture deformity often requires some form of surgical treatment. There are very few long-term reports on release of contracted muscles and tendon transfers, especially in older children. We are reporting the single-center results of such a surgery with detailed outcome analysis.

Methods

The prospectively collected data from brachial plexus birth palsy cases who had undergone contracture release and tendon transfer were retrospectively studied and examined. The new Mallet and functional scores were compared with the original data forms and then analyzed. The radiographic evidence of glenoid dysplasia and its correlation with age and functional outcome was assessed.

Results

A total of 82 cases with surgery at mean age of 9.5 ± 5.09 years and a follow-up of 8 ± 3.8 (3-20) years entered the study. Of these, 56% of cases had 7 to 20 years of age at surgery. Fifty-four (66%) patients had only shoulder surgery, and 28 (34%) required additional reconstructive surgeries for hand and wrist. Moderate to severe glenohumeral dysplasia was present in 38%. The preoperative Mallet score of 10.6 ± 2.97 improved to 19.3 ± 3.39 (P < .001). Eighty-one percent of patients showed improvement in “reaching face” functions, 71% in “above head” functions, and 74% in “midline functions.” The cases with lack of improvement in midline function mostly belonged to pan-plexus injuries. Noticeable subjective and objective improvement was also observed in cases with glenohumeral dysplasia in their Mallet and functional scores (P < .001). The improvement in function and subjective satisfaction of 92% was observed irrespective of age at surgery.

Conclusion

Soft-tissue release and tendon transfer for brachial plexus birth palsy shoulder can improve function and limb appearance even in older children and young adults and even in the presence of glenohumeral dysplasia.

Glenoid Orientation and Profile in Atraumatic or Microtraumatic Posterior Shoulder Instability: Morphological Analysis Using Computed Tomography Arthrogram

Background:

Posterior shoulder instability (PSI) is a relatively uncommon condition that occurs in about 10% of patients with shoulder instability. PSI is usually associated with dislocations due to acute trauma and multidirectional instability, but it can also occur with or without recognizable recurrent microtrauma. The infrequency of atraumatic or microtraumatic PSI and the lack of a full understanding of the pathoanatomy and the knowledge of management can lead to misdiagnosis or delayed diagnosis.

Purpose:

To evaluate the morphologic factors of the glenoid that are associated with atraumatic or microtraumatic PSI.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Enrolled in this study were patients who underwent arthroscopic posterior labral repair between January 2013 and March 2017 and were diagnosed with posterior glenohumeral instability by means of preoperative computed tomography arthrography (CTA) (n = 39; PSI group). These patients did not have any significant dislocation or subluxation episodes. The morphologic factors of the glenoid as revealed using CTA were compared with the CTA images from a sex-matched control group (n = 117) of patients without PSI who had been diagnosed with adhesive capsulitis in an outpatient clinic. The glenoid version and shape were evaluated between the 2 groups using the CTA findings, and the degree of centricity of the humeral head to the glenoid was assessed in the PSI group. Multivariate logistic regression analysis was performed to identify factors associated with PSI.

Results:

The results of the multivariate logistic regression analysis indicated no statistically significant difference between the PSI and control groups regarding glenoid version or a flat-shaped glenoid. However, statistically significant between-group differences were found regarding convex glenoid shape, with an odds ratio of 5.39 (95% CI, 1.31-23.35; P = .0207). The proportion of eccentricity was significantly higher in the PSI group (21/39; 54%) versus the control group (47/117; 40%) (P = .031).

Conclusion:

The presence of convex glenoid shape was significantly associated with atraumatic or microtraumatic PSI. Humeral head eccentricity accounted for a high percentage of convex glenoid shape. However, there was no significant correlation between PSI and glenoid retroversion.

Efficacy of 3 therapeutic taping configurations for children with brachial plexus birth palsy

STUDY DESIGN

Cross-sectional clinical measurement study.

INTRODUCTION

Scapular winging is a frequent complaint among children with brachial plexus birth palsy (BPBP). Therapeutic taping for scapular stabilization has been reported to decrease scapular winging.

PURPOSE OF THE STUDY

This study aimed to determine which therapeutic taping construct was most effective for children with BPBP.

METHODS

Twenty-eight children with BPBP participated in motion capture assessment with 4 taping conditions: (1) no tape, (2) facilitation of rhomboid major and rhomboid minor, (3) facilitation of middle and lower trapezius, and (4) facilitation of rhomboid major, rhomboid minor, and middle and lower trapezius (combination of both 2 and 3, referred to as combined taping). The participants held their arms in 4 positions: (1) neutral with arms by their sides, (2) hand to mouth, (3) hand to belly, and (4) maximum crossbody adduction (CBA). The scapulothoracic, glenohumeral and humerothoracic (HT) joint angles and joint angular displacements were compared using multivariate analyses of variance with Bonferroni corrections.

RESULTS

Scapular winging was significantly decreased in both the trapezius and combined taping conditions in all positions compared with no tape. Rhomboids taping had no effect. Combined taping reduced HT CBA in the CBA position.

CONCLUSIONS

Rhomboid taping cannot be recommended for treatment of children with BPBP. Both trapezius and combined taping approaches reduced scapular winging, but HT CBA was limited with combined taping. Therefore, therapeutic taping of middle and lower trapezius was the most effective configuration for scapular stabilization in children with BPBP. Resting posture improved, but performance of the positions was not significantly improved.

LEVEL OF EVIDENCE

Level II.

The Pathogenesis of Glenohumeral Deformity and Contracture Formation in Obstetric Brachial Plexus Palsy-A Review

Contractures of the shoulder joint and glenohumeral joint dysplasia are well known complications to obstetrical brachial plexus palsy. Despite extensive description of these sequelae, the exact pathogenesis remains unknown. The prevailing theory to explain the contractures and glenohumeral joint dysplasia states that upper trunk injury leads to nonuniform muscle recovery and thus imbalance between internal and external rotators of the shoulder. More recently, another explanation has been proposed, hypothesizing that denervation leads to reduced growth of developing muscles and that reinnervation might suppress contracture formation. An understanding of the pathogenesis is desirable for development of effective prophylactic treatment. This article aims to describe the current state of knowledge regarding these important complications.

Scapular Stabilization Limits Glenohumeral Stretching in Children With Brachial Plexus Injuries

PURPOSE

To quantify the effects of scapular stabilization on scapulothoracic and glenohumeral (GH) stretching.

METHODS

Motion capture data during external rotation and abduction with and without scapular stabilization were collected and analyzed for 26 children with brachial plexus birth palsy. These positions were performed by an experienced occupational therapist and by the child's caretaker. Scapulothoracic and GH joint angular displacements were compared between stretches with no stabilization, stabilization performed by the therapist, and stabilization performed by the caretaker. The relationship between the age and ability of the therapist and caretaker to perform the stretches with scapular stabilization was also assessed.

RESULTS

During external rotation there were no significant differences in either the scapulothoracic or GH joint during stabilization by either the therapist or the caretaker. During abduction, both scapulothoracic and GH joint angular displacements were statistically different. Scapulothoracic upward rotation angular displacement significantly decreased with scapular stabilization by the therapist and caretaker. Glenohumeral elevation angular displacement significantly decreased with scapular stabilization performed by the therapist and caretaker. There were only weak correlations between age and the differences in scapulothoracic and GH joint angular displacement performed by both the therapist and the caretaker.

CONCLUSIONS

The findings of this study indicate that scapular stabilization may be detrimental to passive stretching of the GH joint in children, as demonstrated by a reduced stretch. Based on the findings of this study, we have changed our practice to recommend passive stretches without scapular stabilization for children aged 5 years and older with brachial plexus birth palsy. In infants and children aged less than 5 years, we now recommend stretching with and without scapular stabilization until the effect of scapular stabilization is objectively assessed in these age groups.

LEVEL OF EVIDENCE/TYPE OF STUDY

Therapeutic IV.

Humeral retroversion and shoulder muscle changes in infants with internal rotation contractures following brachial plexus birth palsy

AIM

To examine humeral retroversion in infants who sustained brachial plexus birth palsy (BPBI) and suffered from an internal rotation contracture. Additionally, the role of the infraspinatus (IS) and subscapularis (SSc) muscles in the genesis of this bony deformation is explored.

METHODS

Bilateral magnetic resonance imaging (MRI) scans of 35 infants (age range: 2-7 mo old) with BPBI were retrospectively analyzed. Retroversion was measured according to two proximal axes and one distal axis (transepicondylar axis). The proximal axes were: (1) the perpendicular line to the borders of the articular surface (humeral centerline); and (2) the longest diameter through the humeral head. Muscle cross-sectional areas of the IS and SSc muscles were measured on the MRI-slides representing the largest muscle belly. The difference in retroversion was correlated with the ratio of muscle-sizes and passive external rotation measurements.

RESULTS

Retroversion on the involved side was significantly decreased, 1.0° vs 27.6° (1) and 8.5° vs 27.2° (2), (P < 0.01), as compared to the uninvolved side. The size of the SSc and IS muscles on the involved side was significantly decreased, 2.26 cm² vs 2.79 cm² and 1.53 cm² vs 2.19 cm², respectively (P < 0.05). Furthermore, the muscle ratio (SSc/IS) at the involved side was significantly smaller compared to the uninvolved side (P = 0.007).

CONCLUSION

Even in our youngest patient population, humeral retroversion has a high likelihood of being decreased. Altered humeral retroversion warrants attention as a structural change in any child being evaluated for the treatment of an internal rotation contracture.

Analysis of normal and dysplastic glenohumeral morphology at magnetic resonance imaging in children with neonatal brachial plexus palsy

BACKGROUND

Glenoid version and percentage of the humeral head anterior to the scapular line are commonly used 2-D measures to assess deformity of the glenohumeral joint of children with neonatal brachial plexus palsy.

OBJECTIVE

To assess whether glenoid version and percentage of the humeral head anterior to the scapular line would be altered by standardizing the measurements to the orientation of the scapula.

MATERIALS AND METHODS

Twenty-one bilateral magnetic resonance imaging (MRI) scans were evaluated by four reviewers. Measurements were performed on the axial image slices and again after applying 3-D reformatting.

RESULTS

Three-dimensional reformatting led to intrapatient corrections up to 25° for version and -30% for percentage of the humeral head anterior to the scapular line. The mean difference on the involved side between clinical and anatomical version across all subjects from all reviewers was 2.2° ± 3.9° (range: -4.5° to 11.5°). The mean difference in the percentage of the humeral head anterior to the scapular line after reformatting was -1.8% (range: -15.9% to 5.2%).

CONCLUSION

Measurements can differ greatly for the same child depending on technical factors of image acquisition and presentation in the clinical setting. With this study, we present a clinically accessible protocol to correct for scapular orientation from MRI data of children with neonatal brachial plexus palsy.

Humeral Retroversion in Children with Shoulder Internal Rotation Contractures Secondary to Upper-Trunk Neonatal Brachial Plexus Palsy

BACKGROUND

The most common sequela of neonatal brachial plexus palsy is an internal rotation contracture of the shoulder that impairs function and leads to skeletal deformation of the glenohumeral joint. Treatment options include release, transfers, and humeral osteotomy, all ultimately striving for better function through increased external rotation. Prior studies have shown that neonatal brachial plexus palsy alters humeral retroversion but with conflicting findings. We studied retroversion in children with internal rotation contractures from neonatal brachial plexus palsy to clarify its effect on version and surgical planning.

METHODS

Bilateral shoulder and elbow magnetic resonance imaging scans of 21 children with neonatal brachial plexus palsy were retrospectively analyzed. Retroversion referenced to the transepicondylar line at the elbow was measured with respect to 2 different proximal reference axes, the longest diameter of an axial cut of the proximal part of the humerus (the skew axis) and the line perpendicular to the articular surface (the humeral center line). Glenoid version and glenohumeral morphology type (concentric glenoid, posterior-concentric glenoid, biconcave, or pseudoglenoid) were also determined. All geometric variables were assessed for correlation with patient age and the severity of the internal rotation contracture.

RESULTS

Retroversion on the involved side was decreased at 6° compared with 19° (p = 0.003), as measured between the skew axis and transepicondylar line. Retroversion referenced to the humeral center line was also decreased at -2° (anteversion) compared with 20° (p < 0.001). Patient age was inversely correlated with retroversion, but was only significant for the skew axis (r = -0.497, p = 0.022), decreasing in linear regression by 2.4° per year (p = 0.038). Humeral retroversion did not correlate with the severity of the internal rotation contracture, glenoid version, or glenoid morphology type.

CONCLUSIONS

Humeral retroversion is likely to be less on the affected side in children with internal rotation contractures from upper trunk neonatal brachial plexus palsy and merits consideration in surgical planning.

LEVEL OF EVIDENCE

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

The natural history and management of brachial plexus birth palsy

Brachial plexus birth palsy (BPBP) is an upper extremity paralysis that occurs due to traction injury of the brachial plexus during childbirth. Approximately 20 % of children with brachial plexus birth palsy will have residual neurologic deficits. These permanent and significant impacts on upper limb function continue to spur interest in optimizing the management of a problem with a highly variable natural history. BPBP is generally diagnosed on clinical examination and does not typically require cross-sectional imaging. Physical examination is also the best modality to determine candidates for microsurgical reconstruction of the brachial plexus. The key finding on physical examination that determines need for microsurgery is recovery of antigravity elbow flexion by 3-6 months of age. When indicated, both microsurgery and secondary shoulder and elbow procedures are effective and can substantially improve functional outcomes. These procedures include nerve transfers and nerve grafting in infants and secondary procedures in children, such as botulinum toxin injection, shoulder tendon transfers, and humeral derotational osteotomy.

Therapeutic Taping for Scapular Stabilization in Children With Brachial Plexus Birth Palsy

OBJECTIVE. In this study, we aimed to assess whether therapeutic taping for scapular stabilization affected scapulothoracic, glenohumeral, and humerothoracic joint function in children with brachial plexus birth palsy and scapular winging.

METHOD. Motion capture data were collected with and without therapeutic taping to assist the middle and lower trapezius in seven positions for 26 children. Data were compared with one-way multivariate analyses of variance.

RESULTS. With therapeutic taping, scapular winging decreased considerably in all positions except abduction. Additionally, there were increased glenohumeral cross-body adduction and internal rotation angles in four positions. The only change in humerothoracic function was an increase of 3° of external rotation in the external rotation position.

CONCLUSION. Therapeutic taping for scapular stabilization resulted in a small but statistically significant decrease in scapular winging. Overall performance of positions was largely unchanged. The increased glenohumeral joint angles with therapeutic taping may be beneficial for joint development; however, the long-term impact remains unknown.

Imaging assessment of glenohumeral dysplasia secondary to brachial plexus birth palsy

Objective

To assess imaging parameters related to the morphology of the glenohumeral joint in children with unilateral brachial plexus birth palsy (BPBP), in comparison with those obtained for healthy shoulders.

Materials and Methods

We conducted a retrospective search for cases of unilateral BPBP diagnosed at our facility. Only patients with a clinical diagnosis of unilateral BPBP were included, and the final study sample consisted of 10 consecutive patients who were assessed with cross-sectional imaging. The glenoid version, the translation of the humeral head, and the degrees of glenohumeral dysplasia were assessed.

Results

The mean diameter of the affected humeral heads was 1.93 cm, compared with 2.33 cm for those of the normal limbs. In two cases, there was no significant posterior displacement of the humeral head, five cases showed posterior subluxation of the humeral head, and the remaining three cases showed total luxation of the humeral head. The mean glenoid version angle of the affected limbs (90-α) was -9.6º, versus +1.6º for the normal, contralateral limbs.

Conclusion

The main deformities found in this study were BPBP-associated retroversion of the glenoid cavity, developmental delay of the humeral head, and posterior translation of the humeral head.

Three-Dimensional Magnetic Resonance Imaging of Glenohumeral Dysplasia in Neonatal Brachial Plexus Palsy

BACKGROUND

Existing quantitative measurements of glenohumeral dysplasia in children with unresolved neonatal brachial plexus palsy (NBPP) have been mostly limited to the axial plane. The purpose of this study was to describe the three-dimensional (3D) pathoanatomy of glenohumeral dysplasia using 3D magnetic resonance imaging (MRI) reformations.

METHODS

3D MRI reformations of the scapula, glenoid labrum, and proximal part of the humerus were created from a volume-acquisition proton-density-weighted MRI sequence of both the affected and the unaffected shoulder of seventeen children less than six years of age with unresolved NBPP who had not undergone shoulder surgery. Glenoid retroversion and posterior humeral head displacement were measured on axial 2D images. Humeral head displacement in all planes, labral circumference, glenoid retroversion, glenoid declination, and scapular morphometric values were measured on 3D reformations. Contiguity of the humeral head with the labrum and the shape of the glenoid were classified. Measurements were compared between the affected and unaffected sides.

RESULTS

On 3D evaluation, the humeral head was completely posteriorly translated in ten patients but was never outside the glenoid labrum. Instead, in these patients, the humeral head was eccentrically articulating with the dysplastic glenoid and was contained by a posteriorly elongated labrum. Glenoid dysplasia was not limited to the axial plane. Less declination of the glenoid in the coronal plane correlated with greater 3D glenoid retroversion. Glenoid retroversion resulted from underdevelopment of the posterior aspect of the glenoid rather than overdevelopment of the anterior aspect of the glenoid. 3D measurements of greater glenoid retroversion and less declination correlated with 2D measurements of glenoid retroversion and posterior humeral head displacement.

CONCLUSIONS

Posterior humeral head displacement in NBPP should not be considered a simple "dislocation." Glenohumeral dysplasia is not limited to the axial plane. Abnormal glenoid declination may have potential implications for the evaluation and treatment of shoulder weakness and contractures.

Prevalence of Posterior Shoulder Subluxation in Children With Neonatal Brachial Plexus Palsy After Early Full Passive Range of Motion Exercises

BACKGROUND

Children with neonatal brachial plexus palsy (NBPP) are often prescribed shoulder range of motion (ROM) exercises; however, the extent and timing of exercise implementation remains controversial in the context of shoulder joint integrity. The association of ROM exercises to delayed posterior shoulder subluxation (PSS) is unknown.

OBJECTIVE

To determine prevalence of PSS in children with NBPP who began full passive ROM exercises before 6 months of age, and characteristics associated with development or absence of PSS in children.

DESIGN

Cross-sectional study.

SETTING

Tertiary care NBPP referral center.

PARTICIPANTS

Forty-six children with NBPP, aged 24-57 months, who began full ROM exercises before 6 months of age.

METHODS

One radiologist conducted bilateral shoulder ultrasound (US) on each child to evaluate for PSS. One occupational therapist evaluated each child clinically for PSS using defined parameters without knowledge of US results.

MAIN OUTCOME MEASURES

By US, 20% of children had PSS; 46% had PSS by clinical examination. Shoulder active ROM limitations and history of shoulder surgery were associated with presence of PSS. Extent of NBPP was not associated with PSS.

RESULTS

Nine of 46 children (20%) met US criteria for PSS; α angle was 58° ± 21° (mean ± standard deviation [SD]). Twenty-one children (46%) met clinical criteria. Mean age at examination was 35 ± 10 months. Shoulder active ROM (P ≤ .004) was associated with PSS, whereas passive ROM was not (P ≥ .08). History of secondary shoulder surgery and primary nerve graft repair were associated with PSS (P = .04). Extent of NBPP by Narakas classification was not associated with PSS (P = .48).

CONCLUSIONS

Early use of full-arc passive ROM home exercise program is not associated with increased prevalence of PSS in children with NBPP compared to prevalence of PSS in published literature. We suggest careful clinical examination, based on defined criteria, provides a reasonable screening examination for evaluating PSS that can be confirmed by noninvasive US.