Ganga Medical Centre & Hospitals Pvt Ltd

Coimbatore, India.

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Shoulder Deformities following Brachial Plexus Birth Palsy

Despite advances in the prenatal planning and assessment, brachial plexus birth palsy remains an unfortunate possible consequence of a difficult childbirth. The incidence of brachial plexus birth palsy has been reported to be around 0.5 to 2 per 1000 live births. The severity of injury may vary from neuropraxia to neurotmesis to avulsion of the rootlets from the spinal cord. Perinatal risk factors include high birth weight, prolonged labour, breech presentation, shoulder dystocia, previous deliveries resulting in brachial plexus injuries, multiparous pregnancies, breech, assisted (forceps, vacuum) or difficult deliveries, maternal diabetes, cephalo-pubic disproportion.

Deformities in BPBP: Deformities are encountered mostly in brachial plexus birth palsy and only rarely in adults. This is because of the difference in the pathophysiology of the injury. Obstetric brachial plexus palsy is mostly caused by forceful traction during delivery but is not a high energy injury. The lesions in obstetric brachial plexus palsy are always supraclavicular and are usually related to stretch (neuropraxia or axonotmesis), incomplete rupture, or occasional root avulsion. Stretch and incomplete rupture in this group are much more common than adults and hence spontaneous recovery is possible in large number of cases. In cases of complete rupture, the gaps are short, which makes nerve regeneration possible. Some muscles recover earlier, whereas others remain paretic; this leads to muscle imbalance. In addition, motor recovery in many obstetric brachial plexus palsy patients results from misdirection of regenerated axons (cross-innervation). Cross-innervation causes co-contractions of the synergistic and antagonistic muscle groups. Muscle imbalance and co-contractions eventually lead to muscle contractures, the primary cause of shoulder and elbow deformity in late obstetric brachial plexus palsy. The third factor influencing the deformities is growth in the child. The glenohumeral deformity is inevitable consequence and it may occur rather early in life. The development of deformity follows a basic pediatric orthopedic principle that muscle imbalance in a growing child will lead to bone and joint deformity. The shoulder is by far the most frequently affected joint in OBPP. The adduction and medial rotation contracture with all its complications for the glenohumeral joint is most common. Despite flaws in methodology or loss of patient enrollment in many of the natural history studies, there is sufficient evidence from several studies that some asymmetry of the limb is invariably present if the complete neurological recovery has not occurred in first 4-6 weeks of life and it tends to worsen and finally lead to skeletal deformation.

We have observed that except for the few case of paretic type of upper plexus involvement all the children with brachial plexus birth palsy have good recovery of shoulder abductors. Inspite of having good strength of shoulder abduction they have poor range of shoulder abduction. This probably is because of the fact that the shoulder adductors have recovered much earlier than the abductors and hence the late recovering and weaker abductors are actually not allowed to recover to their full potential by the stronger antagonist muscle (adductors and internal rotators). This suppression effect is made worse by the development of the co-contraction between the abductors & adductors and abductors and elbow flexors. Hence the activity of the abductors is completely masked. These children can often benefit from release of the contracted muscles to maximize the range of motion and probably to maintain a congruent joint.

Shoulder movements are important as more distal functions depend on it. Activities requiring raising the arm, such as hair grooming, eating and overhead reaching will be difficult or not possible. This causes dysfunction with activities of daily living or recreational activities that require hand use above the level of the shoulder. In addition, with time, this imbalance can lead to progressive glenohumeral joint subluxation and deformity.

Shoulder deformity requires a thorough assessment which includes detailed clinical examination and radiological examination (CT-scan / MRI). The procedure is tailored to the need of the child. The indication for surgery and type of surgery depends on the clinical findings, age of the child and condition of the joint demonstrated by the CT-scan.

For correction of the adduction contracture i.e. inability to raise the shoulder above the head is the most common problem. For this we perform a soft tissue release procedure like Mod Quad release or selected release of the contracted muscles with or without tendon transfer depending on the findings. Following the surgery we usually apply a splint or slab for 2-3 week following which exercise are started. Some of the results are shown below:

Age - 6 years


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Age - 8 years


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In children who are unable to rotate their arm outwards (lack of external rotation) have internal rotation contracture at the shoulder. It is more of a bony problem and result because of the tilting of the acromion-clavicular triangle over the humeral head which obstructs the external rotation of the shoulder. This deformity is well demonstrated on a CT-scan. Also the internal rotator (subscapularis) and the anterior capsule ligaments of the shoulder joint are very tight and contracted. In cases of severe contracture the shoulder joint may be subluxed or dislocated posteriorly. For these children we perform a Triangular Tilt procedure along with the anterior shoulder release. Children who show posterior instability of the shoulder require urgent intervention to prevent the otherwise inevitable posterior dislocation of shoulder.



Some of our results are shown below:

Age - 5 years


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