April 11, 2024

Obstetrical Brachial Plexus Palsy is due to excessive traction on the brachial plexus during childbirth seen in 2 per 1000 births.

Eg. By pulling the baby’s head away from the shoulder or by exerting traction with the baby’s arm in abduction

Progressive glenoid hypoplasia occurs in 70 % of children with significant internal rotation contracture

Miller’s Review of Orthopaedics 8th Edition

Risk factors

  • Diabetic mother
  • Large for date babies, force delivery, breech presentation, prolonged labor
Types of Obstetrical Brachial Plexus Palsy
Types of Obstetrical Brachial Plexus Palsy

Narakas classification

Group 1C5/C6Abductors + ERs of shoulders + Supinators are paralyzed
Group 2C5/C6/C7Wrist and digital extensors are also paralyzed by weak or absent tricep function
Group 3Entire plexus involvedFlaccid paralysis (finger paralysis is 1st to recover)
Group 4Entire plexus with horner’s signFlaccid paralysis +Horner’s sign
Narakas classification

Horner’s syndrome with the presence of eyelid ptosis and pupillary miosis suggests avulsion of lower brachial plexus

Clinical Features

Floopy/ Flail arm after delivery (day 1, 2, or later)

Erb-Duchenne Palsy

  • C5, C6 +/- C7
  • Arms held by side, internally rotated and pronated
  • Loss of finger extension can be present
  • Abductors, External rotators, and supinators are paralyzed
  • Best prognosis and most common

Klumpe’s Palsy

  • C8 and T1
  • Arm supinated + elbow flexed
  • Loss of intrinsic muscle power in hand
  • Absent reflexes
  • Horner’s syndrome: Unilateral
  • Poor prognosis

Total Plexus Injury

  • Baby’s arm in flail and pale
  • All finger muscles are paralyzed
  • Vasomotor involvement + unilateral horners syndrome
  • Worst prognosis

Sympathetic outflow in babies also encompasses C8 as well as T1, Unlike in adults

Management

Xrays are done

  • Should exclude fractures of the shoulder or the clavicle
  • Position of the humeral head within the glenoid

Observation

Next few weeks

More than 90% cases eventually improves without intervention

Miller’s Review of Orthopaedics 8th Edition
Management of Obstetrical Brachial Plexus Palsy

Operative treatment

Upper brachial plexus avulsion injuries cause impairment of shoulder and elbow function which is very disabling for patients.

Restoration of elbow flexion is the first goal to be achieved in order to restore arm function

Early surgery is to address nerve function, and late surgery to address deformities

Early Neurophysiological studies (at 6 weeks of age) may be a useful adjunct in decision making

No Shoulder activity/ No bicep activity by 3 months needs operative intervention

  • Root avulsed
    • Nerve transfer and tendon transfer are the only options
Nerve transfer include spinal accessory nerve, intercostal nerve and contralateral C7 nerve root
  • Root Not avulsed
    • Excise the scar and bridge the gap with a free sural nerve (graft)

The shoulder is prone to fixed IP and adduction deformity secondary to imbalanced motor activities. This results in progressive posterior dislocation of the shoulder.

Lack of bicep function 6 months after injury and the presence of Horner syndrome carry a poor prognosis

Miller’s Review of Orthopaedics 8th Edition

Physiotherapy is done to prevent this

If not treated by physiotherapy, treatment is done by

  • Release of subscapularis (Commonly in its superior segment)

Supplemented by

  • Tendon and muscle transfer for elbow flexion (Clark pectoral transfer and Steindler flexorplasty)
  • Pectoral and subscapularis release for internal rotation contracture and secondary glenoid hypoplasia (<5 years old)
  • Older children: Rotated osteotomy of the humerus

Steindler flexorplasty is the must commonly used muscle transfer

Fixed flexion deformity

  • Splinting and serial casting

The child should be followed up, with an adolescent growth spurt until the shoulder approaches adult size.

See also: Brachial Plexus Injuries

See also: Thoracic Outlet Syndrome