A brief description is given below:
Congenital : The deformity is usually recognizable at birth and may be associated with congenital anomalies elsewhere in the body. These include:
- Absent digit
- Extra digit
- Fusion of digits ( Syndactyly)
- Primary muscle contractures.
Cleft hand with ring and small finger fusion (syndactyly)
Amniotic construction band of the hand with deformity of index finger
Thumb deformity and absent digits.
Acquired: It may be due to:
1. Trauma: A clinical history of trauma will be present and the deformity depends on the extent of trauma and resulting amputation or surgery.
2. Burns: may lead to deformities and scaring depending on the degree and severity of burn.
3. Dupuytren's contracture; Initially the patient may complain of thickening of the palm near the base of the ring finger. Later there is difficulty to straighten the ring and little finger. On examination there is a firm nodule in the palmar fascia near the base of the ring finger. Puckering of the skin is usually present around the nodule. The MCP joint and PIP are flexed while the DIP is extended. The ring finger is mostly affected followed by little finger.
4. Rheumatoid arthritis: By the time deformities develop the diagnosis of RA is already made. There is thickening of the joints especially MCP and PIP joint. There is ulnar deviation of the fingers. The wrist joint develops a fixed flexion deformity with some ulnar deviation. Swan neck and boutonniere deformities of fingers also become apparent later in disease.
Later stages of rheumatoid arthritis with severe deformities.
5. Volkmann's Ischemic contracture: This is shortening of long flexor muscles of forearm due to ischemia. There may be a history of trauma e.g supracondylar fracture of the humerus, a tight plaster restricting blood flow or arterial disease e.g embolism. Movement of the fingers are painful and limited. there may be pins and needle sensation in the hand due to pressure on the nerves. Ultimately a claw hand results.The forearm muscles feel hard and taut due to fibrosis.
Volkmann's Ischemic contracture
6. Poliomyelitis: There is a clear past history and the affected part looks reddish blue, wasted and deformed.
7. Syringomyelia: A type of spinal cord lesion causes a variety of hand deformities. With upper motor neuron lesion there may be fixed flexion of the wrist and fingers with adduction of the thumb.
8. Brachial plexus injuries: Upward traction on the arm may damage the lowest root (T1) of the brachial plexus, which is the segmental supply of the intrinsic muscles of the hand. The hand becomes clawed ( klumpke's pralysis) .
9. Ulnar nerve lesions: All intrinsic muscles of the hand (except for the radial lumbricals) are pralysed and the hand appears clawed. The clawing is less for the second and third fingers because the lumbricals are intact.
Claw hand due to ulnar nerve lesion
10 Median Nerve Injury: The wrist at the thenar eminence becomes wasted and fine movements like picking an object become clumsy.