ERB'S PALSY

Definition/Description

Erb's palsy or Erb–Duchenne palsy is a form of obstetric brachial plexus palsy. It

occurs when there's an injury to the brachial plexus, specifically the upper brachial
plexus at birth. The injury can either stretch, rupture or avulse the roots of the plexus
from the spinal cord. It is the most common birth related neuropraxia (about 48%).
It is a lesion of C5 & C6 nerve roots (in some cases C7 is involved as well) usually
produced by widening of the head shoulder interval. Injuries to the brachial plexus
affect movement and cutaneous sensations in the upper limb. Depending on the severity
of the injury, the paralysis can either resolve on its own over a period of months,
require rehabilitative therapy or surgery.

Clinically Relevant Anatomy

Brachial Plexus. Erb's palsy primarily affects C5 and C6.

Neurologically, the Erb's point is a site at the upper trunk of the Brachial

Plexus located 2-3cm above the clavicle. It's formed by the union of the C5 and C6 roots
which later converge. Affected nerves in Erb's palsy are the axillary nerve,
musculocutaneous, & suprascapular nerve.
 Axillary nerve- originates from the terminal branch of posterior cord receiving
fibers from C5 and C6. It exits the axillary fossa
posteriorly passing through the quadrangular space with posterior circumflex humeral
artery. it fives rise to superior lateral brachial cutaneous nerve then winds around the
surgical neck of the humerus deep to deltoid. It innervates the shoulder joint, teres
minor and deltoid muscles, skin of superolateral arm.
 Musculocutaneous nerve- originates from the terminal branch of lateral cord
receiving fibers from C5-C7. It exits the axilla by piercing coracobrachialis, descends
between biceps brachii and brachialis while supplying both, continues as lateral
cutaneous nerve of forearm. It innervates the muscles of the anterior compartment of
the arm and the skin of lateral aspect of the forearm.
 Suprascapular nerve- originates from the superior trunk receiving fibers from
C5, C6 often C4. It passes laterally across lateral cervical region superior to brachial
plexus then through scapular notch inferior to superior transverse scapular ligament. It
innervates the supraspinatus, infraspinatus and shoulder joint.

Epidemiology

Frequency

An incidence of 0.8-1 per 1,000 births has been reported for brachial plexus birth palsy
(BPBP) in the US. Erb's palsy accounts for about 45% of BPBP. Additional injury to C7
is commonly discovered in 20% of cases of BPBP.

Mortality/Morbidity

Incidence of permanent impairment is 3-25%. The rate of recovery in the first few
weeks is a good indicator of final outcome. Complete recovery is unlikely if no
improvement has occurred in the first two weeks of life.
 Race

A study by Weizsaeker et al 2007 found that being a member of the black population
was independently predictive for Erb's palsy.

Mechanism of Injury / Pathological Process

The most common cause of Erb's palsy is excessive lateral traction or stretching of the
baby's head and neck in opposite directions during delivery usually associated with
shoulder dystocia. This may happen during delivery of the head, the head may be
deviated away from the axial plane. There can also be compression of the brachial
plexus causing it to stretch and tear. Sometimes, pulling on the infant's shoulder during
delivery or excessive pressure on the baby's raised arm during a breech delivery can
cause brachial plexus injury. Two potential forces act on the brachial plexus during
labor- natural expulsive force of the uterus, traction force applied by the obstetrician.

Risk Factors

 Shoulder dystocia
 Fetal macrosomia
 Maternal obesity
 Gestational diabetes
 Duration of second stage of labor(over 60 minutes)
 Breech presentation

Clinical Presentation

The classical sign of erb's palsy is called Waiter's tip deformity. This is due to loss of the
lateral rotators of the shoulder, arm flexors, and hand extensor muscles.  The position
of the limb, under such conditions, is characterized by : the arm hanging by the side
and is rotated medially, the forearm extended and pronated and the wrist flexed.
Also,there is loss of sensation in the lateral aspect of the forearm.
 The arm cannot be raised from the side; all power of flexion of the elbow is lost, as is
also supination of the forearm. Muscles most often paralyzed are supraspinatus and
infraspinatus because the suprascapular nerve is fixed at the suprascapular notch
(Erb's point). In more severely affected patients deltoid, biceps, brachialis, and
subscapular is affected (C5 and C6). Elbow flexion is weakened because of weakness in
biceps & brachialis. If roots are damaged above their junction, paralysis of rhomboids
and serratus anterior is added, producing weakness in retraction and protraction of
scapula

Diagnosis

A thorough history and physical examination with focus on neurologic examination are
used to confirm diagnosis.

History- aims to gather information about pregnancy complicated either by gestational

diabetes or maternal obesity, fetal macrosomia, prolonged second stage labour,
shoulder dystocia, use of assitive techniques-forceps to aid delivery.

Physical examination- most often shows decreased or absent movement of the affected
arm.

Neurologic examination- assesses muscle power, sensation,reflexes- moro reflex is

absent on the affected arm.

It might also be important to look for presence of cervical rib. In the report by Becker
J, et al (2002), the authors noted that in a series of 42 infants found to have a cervical
rib, 28 newborns had an Erb's palsy. They concluded that a cervical rib was a risk
factor for an Erb's palsy

Investigations

 X-rays of the chest - to rule out clavicular or humeral fracture

 MRI of the shoulder- may demonstrate shoulder dislocation; presence of
pseudomeningoceles indicates avulsion injury of the affected spinal roots [8][9][10]

 CT Scan of the shoulder- may demonstrate shoulder dislocation; presence of

pseudomeningoceles indicates avulsion injury of the affected spinal roots [8][9][10]

 EMG/Nerve conduction studies- presence of fibrillation potentials indicate

denervation

Outcome Measures

 Toronto test score

 Active movement scale
 Mallet scale

 Toddler Arm Use Test

Management / Interventions

Some brachial plexus injuries may heal without treatment. Many children who are
injured during birth improve or recover by 3 to 4 months of age, although it may take
up to two years to recover. Fortunately, between 80% to 90% of children with such
injuries will attain normal or near normal function [11].  Treatment for brachial plexus
injuries includes physiotherapy and, in some cases, surgery.

Physiotherapy Management

During the first 6 months treatment is directed specifically at prevention of fixed

deformities. Exercise therapy should be administered daily to maintain ROM and
improve muscle strength. Parents must be taught to take an active role in maintaining
ROM and keeping the functioning muscles fit. Exercises should include bimanual or
bilateral motor planning activities.
 Activities and exercises to promote recovery of movement and muscle strength
 Exercises to maintain range of movement in the joints to prevent stiffness and
pain
 Sensory stimulation to promote increased awareness of the arm
 Provision of splints to prevent secondary complications and maximise function
 Educating parents on appropriate handling and positioning of the child and
home exercises to maximise the child’s potential for recovery
 Constraint induced movement therapy may be useful
 Electrical Stimulation may be beneficial
 Referral to Occupational Therapy for assessment of function in day to day
activities

Klumpke's Palsy
Introduction

Klumpke paralysis is a neuropathy of the lower brachial plexus which may be resulted
from a difficult delivery. Usually the eighth cervical and first thoracic nerves are
injured either before or after they have joined to form the lower trunk. This injury can
cause a stretching (neuropraxia,), tearing (called “avulsion” when the tear is at the
spine, and “rupture” when it is not), or scarring (neuroma) of the brachial plexus
nerves. Most infants with Klumpke paralysis have the more mild form of injury
(neuropraxia) and often recover within 6 months. 

The main mechanism of injury is hyper-abduction traction and depending on the

intensity, cause signs and symptoms consistent with a neurological insult.

According to the the National Institute of Neural Disorders and Stroke (NINDS), there
are four types of brachial plexus injuries that cause Klumpke’s :

1. Avulsion, in which the nerve is severed from the spine.

2. Rupture, in which tearing of the nerve occurs but not at the spine.
3. Neuroma, in which the injured nerve has healed but can’t transmit nervous
signals to the arm or hand muscles because scar tissue has formed and puts pressure on
it.
4. Neuropraxia or stretching, in which the nerve has suffered damage but is not
torn.

Risk factors for Klumpke Paralysis are:

1. large birth weight babies,

2. maternal diabetes, 
3. multiparity,
4. difficult presentation,
5. shoulder dystocia,
6. forceps or vaccuum delivery,
7. breech position,
8. prolonged labor,
9. previous child with obstetric palsy,
10. intrauterine torticollis.
11. Less common includes tumors (neuromas, rhabdoid tumors), intrauterine
compression, hemangioma and exostosis of the first rib in the child.

Signs and symptoms:

- “Claw hand” is a classic presentation seen where the forearm is supinated and the
wrist and fingers are flexed.

Other signs and Symptoms include:

1. weakness and loss of movement of the arm and hand. Some babies experience
drooping of the eyelid on the opposite side of the face as well. This symptom may also be
referred to as Horner's syndrome. 
2. decrease of sensation along the medial aspect of the distal upper extremity along
the C8 and T1 dermatome.
3. myotome findings that can range from decreasing muscular strength to muscular
atrophy and positional deformity.
4. Reflexes in the affected roots are absent.
5. associated injuries clavicular and humerus fractures, torticollis,
cephalohematoma, and facial nerve palsy.

- An infant with a nerve injury to the lower plexus (C8-T1) holds the arm supinated,
with the elbow bent and the wrist extended.

Differential Diagnosis

1. Erb's palsy; this injury affects the upper brachial plexus which will usually
result in dermatome and myotome finds along the C5-C6 path,
2. Distal nerve entrapment of the ulnar nerve at either the medial epicondyle of
Guyon's tunnel- produces similar neurological findings as the more proximal
Klumpke's. But there is no involvement of innervation proximal to the lesion, for
example, pectoralis major involvement with true ulnar nerve entrapment.
3. Thoracic outlet syndrome : TOS is a compression injury to the brachial plexus
from a rudimentary rib, first rib, or the clavicle on the ipsilateral side, this could be
post-traumatic, postural driven, and or genetic.It affects more than C8- T1 roots.
4. Apical lung tumor
5. Neurofibroma
6. Disc herniation
7. Shoulder impingement
8. Clavicular or vertebral fracture
9. Other

Management
 Treatment of Klumpke’s injury in babies and children is heavily dependent on the
severity and the classification of the injury.

The affected arm may be immobilized across the body for 7 to 10 days. For mild cases,
gentle massage of the arm and range-of-motion exercises may be recommended.

For torn nerves (avulsion and rupture injuries), symptoms may improve with surgery.   

Surgical Options:

1. Surgery on the nerves (e.g., nerve grafts and neuroma excision).

2.Tendon transfers to help the muscles that are affected by nerve damage work better.

3.Muscle transfer, in which a less important muscle or tendon is removed from another
part of the body and attached to the injured arm if the muscles there deteriorate

Physiotherapy Management

Physical therapy assists in keeping the muscles and joints’ range of motion normal.
Physical therapy also keeps muscles and joints to work properly and prevents stiffness
in joints such as the shoulder, elbow, or wrist. 

Physiotherapy majorly focuses on :

1. improving flexibility,
2. range of motion,
3. strength, and
4. dexterity
5. Pain control