Klumpke palsy is a form of paralysis involving the muscles of the forearm and hand, resulting from a brachial plexus to the eighth cervical and first thoracic nerves are injured either before or after they have joined to form the lower trunk.
Klumpke palsy usually occurs following a stretching injury from a difficult vaginal delivery. Klumpke palsy is rarely reported in cesarean sections. Depending on the severity of the injury, the nerve injury could be stretching of the nerve, avulsion of the root or tearing of the nerve. Neuropraxia is the most common type of injury in Klumpke palsy and most of them recover within 6 months.
The classic presentation of Klumpke’s palsy is the “claw hand” where the forearm is supinated and the wrist and fingers are flexed. If Horner’s syndrome is present, there is constriction of the pupils in the affected eye.
Obstetric brachial plexus injuries occur in approximately 1 in 3,000 births. Erb’s palsy is a common type whereas Klumpke palsy is rarer.
Causes of Klumpke Palsy
Risk factors for Klumpke palsy and other obstetric brachial plexus palsies large birth weight babies, maternal diabetes, multiparity, difficult presentation, shoulder dystocia, forceps delivery, breech position, prolonged labor, assisted delivery (use of forceps or vacuum extraction), previous child with obstetric palsy, intrauterine torticollis.
Less common includes tumors (neuromas, rhabdoid tumors), intrauterine compression, hemangioma and exostosis of the first rib in the child.
Presentation of Klumpke Palsy [Signs and Symptoms]
Klumpke palsy affects C8, T1 fibers, thus affecting the distribution of ulnar and median nerves. Signs and symptoms include weakness and loss of movement of the arm and hand. Horner syndrome can be present.
The infant with a nerve injury to the lower plexus (C8-T1) holds the arm supinated, with the elbow bent and the wrist extended.
There is a decreased grip on the affected side.
In older child claw hand may be noted. The wrist is kept in extreme extension [unopposed force of wrist extensors due to loss of flexors], there is a hyperextension of metacarpophalangeal joint and flexion of interphalangeal joints due to loss of intrinsic muscles of the hand.
Sensory loss is difficult to assess in newborns. Reflexes in the affected roots are absent.
There may be associated injuries clavicular and humerus fractures, torticollis, cephalohematoma, and facial nerve palsy.
Differential Diagnoses of Klumpke Palsy
Brachial plexus injury may be confused with a condition called pseudoparalysis.
Lab studies generally are not necessary for the diagnosis of brachial plexus palsy.
Xray of clavicle along with arm should be done to rule out any fracture. Computed tomography myelography is the most sensitive radiographic study to detect nerve root injuries. High-resolution MRI is the best imaging study available for evaluating neonatal brachial plexus palsy.
Electrodiagnostic studies are used as an extension of the physical examination and can provide data on the severity and timing of the injury.
Treatment of Klumpke Palsy
For the first two weeks, the arm can be fixed across the child’s chest by pinning of his/her clothing to provide more comfort. Few others recommend the earlier range of motion exercises. A splint may be used to maintain proper wrist alignment and reduce the risk of progressive contractures.
More severe cases or those that do not improve in the first few weeks of life may need further evaluation and put on physical therapy. Physical therapy aims at the range of motion exercise, active movement, strengthening, sensory awareness, to minimize bony deformities and joint contractures.
In older children, activities that involve both limbs like swimming, basketball, climbing etc. should be encouraged.
Physical therapy is both for children being managed conservatively, as well as for children who require surgical intervention.
If some strength has not returned to the affected muscles by the time the baby is 3 – 6 months old, surgery may be considered.
Recommendation and timing of surgical intervention are not uniform. Some physicians recommend surgery in as young as 2 months whereas others recommend a delay.
Surgical options are neurolysis or excision of the neuroma and nerve graft reconstruction.
Neurolysis means removal of scar tissue around the nerves. Intraoperative nerve stimulation is done to see transmission across a neuroma. If there is conduction across the neuroma, neurolysis is performed. Nerve grafting is done when the amplitude of the motor unit action potential drops 50% or more as it crosses the neuroma. Generally, sural nerve is used for grafting.
Nerve transfer or neurotization is performed in cases there is not a sufficient donor nerve.
Tubulization is an adjuvant technique when an insufficient amount of autologous nerve graft is available.
Tendon transfers and/or osteotomies may be needed in some cases to improve the flexibility and active movement of the joints.
Neuromuscular electrical stimulation is a modality in which muscles are stimulated by pulsating alternating currents and has been reported to increase blood flow and possibly muscle bulk but its effect on reinnervation is not clear.