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DIAGNOSIS WRIST INJURIES
Ganglion and dorsal impingement Ganglion cysts Ganglion cysts are idiopathic but probably reflect a variation in normal joint or tendon sheath function. Cysts near joints are connected to the joint. The leading theory is that a type of check valve forms that allows fluid out of the joint but not back in. The cyst contains clear fluid similar to, but thicker than, normal synovial fluid. They are most often found around the scapho- lunate joint but can occur anywhere around the wrist joint (Fig. 7). Diagnosis may be made clinically, or small ganglion cysts can be identified on ultrasound or MRI. However, the cysts are often incidental and therefore it is important to ensure that this is the cause of the painful wrist rather than masking another cause. Ganglion cysts often come and go
spontaneously, and so most of the time they can be left alone. Symptomatic ganglions can be treated by direct pressure (traditionally hitting it with the family Bible!), aspirated or excised, but all of these methods have a risk of recurrence (70–80% with pressure, 40% with aspiration, 10% with excision).
Impingement Dorsal synovial impingement is common in sports that involve repetitive hyperextension. It is caused by the capsule and synovium snagging between the distal edge of the radius and the back of the lunate-capitate on extension. The athlete complains of pain on hyperextension under load, pointing to the back of the wrist joint. On examination, there is focal tenderness and the pain is reproduced by forced passive hyperextension. Occasionally, ultrasound or MRI shows a lesion (and excludes the differential diagnosis of a small or occult dorsal wrist ganglion). If suspected clinically, then a cortisone injection is both diagnostic and therapeutic. Immobilisation in a splint is helpful. For refractory cases, or to secure the diagnosis, wrist arthroscopy is recommended.
TFCC injuries The TFCC is the stabiliser of the wrist joint and consists of triangular cartilage, ulnar meniscus, ulnar collateral and carpal ligaments, and ECU tendon. It can be injured in two ways. A central perforation occurs with
a fall on the outstretched hand but more frequently occurs as a natural degenerative process in patients with a relatively long ulna (ulno- carpal impaction; Fig. 8). The patient has pain in the ulnar corner, which is worse on sporting manoeuvres needing ulnar tilt. On examination, there is tenderness over the ulnar head, with pain provoked by forced ulnar tilt. Diagnosis is confirmed by MRI arthrography. A cortisone injection helps mild cases; more severe cases need arthroscopic surgery to trim the tear and decompress the ulnar head. A peripheral detachment occurs with a violent wrench or fall in rotation on the hand. The distal radio-ulnar joint becomes unstable. This is a rare but disabling injury for the athlete. Diagnosis is confirmed by anteroposterior instability on balloting (compressing) the ulnar head. Treatment requires surgery (arthroscopic or open) and prolonged rehabilitation.
Neuropathy Carpal tunnel syndrome This condition is caused by compression of the median nerve (Fig. 9) within the carpal tunnel of the wrist, leading to tingling and pain or paraesthesia in the median nerve territory of the hand (thumb, index, middle and radial side of the ring fingers). Symptoms may radiate to the elbow and are often worse at night. It is important to exclude the neck as the source of the pain.
The condition is seen in sports that involve repetitive wrist flexion
(eg. rowing) and in sports with direct pressure on the nerve (eg. cycling, handball).
Diagnosis is usually clinical with a
positive Phalen’s test (passive wrist flexion reproducing symptoms) or Tinel’s test (tingling in the median nerve territory of the hand by tapping over the median nerve in the wrist). Thenar muscle wasting and established sensory loss indicate severe compression and justify urgent assessment for surgical release. If there is diagnostic doubt, then nerve conduction tests confirm the cause. In mild cases, treatment consists
of relative rest, NSAIDs and night splints, although these are often poorly tolerated. A cortisone injection into the carpal tunnel is effective in around 70% of cases. Surgical decompression is usually curative.
Ulnar nerve compression The ulnar nerve can be compressed as it passes through Guyon’s canal. It is often seen in cyclists who use drop- handlebars due to direct pressure over the nerve as the wrist is forced into ulnar deviation. Compression causes pain and paraesthesia in the little finger, ulnar side of the ring finger and hypothenar eminence. In severe cases there is reduced grip, with wasting of the hypothenar and interosseous muscles. Diagnosis is often made clinically
but, again, nerve conduction tests may be necessary.
Mild cases usually resolve with relative rest, NSAIDs and a change of
OBJECT OR FALLING ONTO AN OUTSTRETCHED HAND. THERE ARE ALSO SOME ATHLETES WHO INJURE THEIR WRISTS IN WEIGHT TRAINING, WHERE POOR TECHNIQUE OR TOO HEAVY WEIGHT LEADS TO HYPEREXTENSION INJURIES.
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ACUTE WRIST INJURIES MAINLY OCCUR FROM ACUTE TRAUMA, SUCH AS BEING HIT BY AN