A SIMPLE CLINICAL TEST OF FLEXOR POLLICIS R

he ng ibl nco p n V intact flexor pollicis longus tendon in the presence of an incomplete anterior interosseous nerve palsy(Hill et al., 1985; Joist et al., 1998). Also reported is delayed diagnosis (McLain with the drome is function w um profun complete a reliably demonstrates an intact flexor pollicis longus preferential involvement of nerve fibres destined for the anterior interosseous nerve. aluate the it. Mody r pollicis ntaneous b occurs metacarpophalangeal joints of the thumb. ARTICLE IN PRESSdetermine the presence of anteriortendon, and, when active thumb flexion at the inter-phalangeal joint is lost, will differentiate between rupture of this tendon and a muscle which is non-contractile as a result of anterior interosseous nerve palsy. MRI scanning has been used to assess the continuity of the flexor pollicis longus in patients with loss of thumb interphalangeal joint flexion (Drape et al., 1998) and neurophysiological studies are used to try to interosseous nerve 624This paper describes a simple clinical test which on forced hyperextension of the carpometacarpal andas an anterior interosseous nerve palsy and Steyers, 1990). The diagnostic difficulty incomplete anterior interosseous nerve syn-mainly due to loss of flexor pollicis longus ith preservation of function of flexor digitor-dus to the index finger. The latter is lost in nterior interosseous nerve palsy. DISCUSSION We describe here a simple test with which to ev flexor pollicis longus musculotendinous un (1992) described an alternative test of flexo longus continuity: if the tendon is intact, spo flexion of the interphalangeal joint of the thumtreatment of flexor pollicis longus rupture followingLONGU