Elbow Flexion Contractures in Childhood in Obstetric Brachial Plexus Lesions: A Longitudinal Study of 20 Neurosurgically Reconstructed Infants with 8-Year Follow-up

Management of Brachial Plexus Birth Injuries at British Columbia Children's Hospital

A multidisciplinary team at BC Children's Hospital provides brachial plexus birth injury management for our provincial catchment area. Although compared with many centers we service a relatively small clinic population, we have the benefit of universal health care, province-wide reach, and accessible research infrastructure. In 2008, we created the Sup-ER protocol, which includes an orthosis that passively positions the neonatal shoulder into more idealized glenohumeral contact during early growth. We have since shown that our Sup-ER patients have better shoulder outcomes, require less brachial plexus surgery, and need fewer shoulder tendon transfers than those patients treated in our clinic prior to 2008. We have also found that the rate and degree of elbow flexion contractures are reduced compared with results reported in the literature.

Can the Sup-ER Protocol Decrease the Prevalence and Severity of Elbow Flexion Deformity in Brachial Plexus Birth Injuries?

BACKGROUND

Brachial plexus birth injuries (BPBIs) can often result in functional and cosmetic deficits including, according to a recent scoping review, elbow flexion contractures in up to 48%. A treatment algorithm that includes a custom long-arm orthosis to optimize early glenohumeral joint positioning (Sup-ER protocol) has been shown to improve shoulder range of motion. Although the protocol was not intentionally designed to affect the elbow, this study investigates the prevalence and severity of elbow flexion contractures in children treated with that protocol.

METHODS

This prospective cross-sectional cohort study examined 16 children aged 4 and older with BPBI severe enough to be treated with the Sup-ER protocol. Passive and active elbow flexion and extension range of motion (ROM) were assessed in both arms. Elbow flexion contractures were defined as > 5^o from neutral.

RESULTS

Within the cohort of 16 patients (mean age: 7.0 years, range: 4.5-11.6 years), the mean maximal passive elbow extension was -6.2° in the affected arm and + 5.1° (hyperextension) in the unaffected arm. Zero patients had a severe elbow flexion contracture (>30^o) and only 6/16 met the lowest threshold definition of elbow flexion contracture (>5^o), with a mean onset at 22 months of age.

CONCLUSIONS

This study suggests an unintended decreased prevalence and severity of elbow flexion contractures in children with more severe BPBI treated with the Sup-ER protocol, relative to published values.

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.

Effectiveness of non-surgical and surgical interventions for elbow flexion contractures in brachial plexus birth injury: A systematic review

PURPOSE

To conduct a systematic review of studies on non-surgical and surgical interventions for elbow flexion contractures secondary to brachial plexus birth injury (BPBI).

METHODS

MEDLINE, EMBASE, PsycINFO, and CINAHL databases were searched for randomized controlled trials, observational studies, and case series studies on treatment of elbow flexion contractures secondary to BPBI. Study quality was evaluated using the Effective Public Health Practice Project tool.

RESULTS

Of the 950 records found, 132 full text articles were reviewed, and 3 cohort studies and 8 case series were included. The overall methodological quality of included studies was weak. The weak quality evidence demonstrated that significant gains in elbow extension passive range of motion (ROM) can be achieved with serial casting (range: 15 to 34.5 degrees) or elbow release surgery (range: 28.4 to 30.0 degrees). At best, a reduction to an elbow contracture between -15.0 and -18.8 degrees (casting) and -8.0 and -43.6 (elbow release surgery) can be achieved. Insufficient outcomes on elbow flexion ROM and strength were found in both non-surgical and surgical studies.

CONCLUSION

The quality of evidence on the effectiveness of interventions for an elbow flexion contracture secondary to BPBI is weak. In the context of insufficient evidence on the risks of pursuing such interventions, it is prudent to attempt non-surgical interventions prior to surgery.

LEVEL OF EVIDENCE

III - systematic review of level IV studies.

Prevalence and etiology of elbow flexion contractures in brachial plexus birth injury: A scoping review

PURPOSE

To synthesize the evidence on the prevalence and etiology of elbow flexion contractures secondary to brachial plexus birth injury (BPBI).

METHODS

Using Arksey and O'Malley's scoping review framework, MEDLINE, EMBASE, PsycINFO, and CINAHL databases were searched, followed by a comprehensive grey literature search. Articles and abstracts of studies of all level of evidence on the prevalence, natural history, clinical presentation, etiology, and treatment of elbow flexion contractures in BPBI were included.

RESULTS

Of the 884 records found, 130 full text articles were reviewed, and 57 records were included. The median prevalence of elbow flexion contracture in BPBI was 48%. The magnitude of the contractures was between 5 and 90 degrees. Contractures > 30 degrees were found in 21% to 36% of children. With recent clinical and lab studies, there is stronger evidence that the contractures are largely due to the effects of denervation causing failure in the growth of the affected flexor muscles, while muscle imbalance, splint positioning, and postural preferences play a smaller role.

CONCLUSION

The etiology of elbow flexion contractures is multifaceted. The contribution of growth impairment in the affected muscles offers greater understanding as to why maintaining passive range of motion in these contractures can be difficult.

What influences contracture formation in lower motor neuron disorders, severity of denervation or residual muscle function? An analysis of the elbow contracture in 100 children with unilateral Brachial Plexus Birth Injury

PURPOSE

As in other neuromuscular disorders, both denervation and muscle paresis/imbalance are implicated as aetiological factors for contractures in children with a Brachial Plexus Birth Injury (BPBI). Although both factors are related, it is unclear which factor is dominant. The aim of this study is to assess whether contracture formation in children is predominantly related to denervation or to residual muscle function/imbalance. This might be relevant for understanding contracture formation in other neuromuscular disorders.

METHODS

A total of 100 children (61 boys; mean age 10.4 years, 4 to 18) with unilateral BPBI were included in this cross-sectional study. Severity of the denervation was classified according to Narakas. Muscle function of flexors and extensors of both elbows was measured (in Newtons) using a hand-held dynamometer and flexion contractures were measured with a goniometer. The relation between denervation, muscle function/muscle balance and flexion contracture was assessed using univariate and multivariate analysis.

RESULTS

Of the children, 57 were Narakas class I, 13 class II and 30 class III. Mean flexion contracture was 25° (90° to -5°). At the affected side the forearm flexion force was 47% and extension force was 67% of the force of the unaffected side. Contractures were more severe in children with higher Narakas classifications (p = 0.001), after neurosurgery (Mann-Whitney U test, p = 0.009) and were related to age (Spearman's Rho = -0.3, p = 0.008) and to paresis of the extensors (Rho = 0.4, p = 0.000). Flexor paresis as a percentage of unaffected side (Rho = 0.06, p = 0.6) and muscle balance had no influence.

CONCLUSION

In BPBI, elbow contractures are related to the severity of the neurological lesion, not to residual muscle function.

LEVEL OF EVIDENCE

Level II - prognostic study.