Claw Hand, A Simple Guide To The Condition, Diagnosis, Treatment And Related Conditions

Claw hand is a medical deformity of the hand that causes abnormally bent or curved fingers. This abnormally makes the hand appear similar to the claw of an animal. A claw hand may be frightening to other children and some adults because of the shape of the hand. The disorder may be caused by a congenital deformity that is detected at birth (congenital), or because of an injury to the ulnar nerveThe claw hand deformity is manifested by flattening of the longitudinal arches and transverse metacarpal arch, with hyperextension of MCP joints and flexion of the PIP and DIP joints.
The deformity is induced by imbalance of the intrinsic and extrinsic muscles:1. The intrinsic muscles must be significantly weakened or paralyzed to cause claw deformity2. The long extensor muscles hyperextend the MCP joint and long flexor muscles flex the PIP and DIP joints3. The weakness of the long flexors (as in high palsy) actually reduces claw fingers4. The PIP joint loses the ability to extend through the lateral bands and must depend on the central slip5.
Due to the anatomy of the sagittal band, MP joint hyperextension obstructs the central slip from extending the PIP6. The main energy of contracted extensor mechanism is directed on sagittal band, resulting in further MCP hyperextension7. The tenodesis action of extending the fingers with wrist flexion is lostCauses may include:1. Congenital abnormality (present at birth)2. Damage to the ulnar nerve3.
Scarring after a severe burn of the hand or forearm4. Nerve palsy due to leprosyWorldwide, the nerve palsy due to leprosy still is the most common cause of the claw handThe classic claw hand involves the flexion of the inter-phalangeal joints and hyperextension of the metacarpo-phalangeal joints with attempts to extend the digits. Surgery is done to treat abnormalities that may be causing the claw hand, such as nerve disorders, tendon anomalies, joint contractures, or scar tissueIf the nerves are not repairable or repairs have failed, tendon transfers can be done.
Tendon transfers at best correct the claw deformity and thumb collapseIt does little to recover the functional disability of loss of abduction or adduction of the fingers or thumb collapse. Rehabilitation with physiotherapy and splintage may help the patient:a. Splintingb. Treatment to straighten the fingersNon-surgical treatment measures for acquired form of Claw Hand are:a. Non-steroidal anti-inflammatory oral medications, such as indomethacin and naproxen, may be used to help reduce the pain and swellingb.
Complete immobilization of the hand with a cast may be needed, to restrict movementTABLE OF CONTENTIntroductionChapter 1 Claw HandChapter 2 CausesChapter 3 SymptomsChapter 4 DiagnosisChapter 5 TreatmentChapter 6 PrognosisChapter 7 Carpal Tunnel SyndromeChapter 8 Dupuytrens ContractureEpilogue