LOCKING OF THE METACARPOPHALANGEAL JOINT CAUSED BY OSTEOPHYTE OF THE METACARPAL HEAD OF THE MIDDLE FINGER

Abstract

Locking of the MCP joint of the finger, except with stenosing tenosynovitis, is relatively rare. The middle finger is most frequently involved. We treated 7 patients who had locking of the MCP joint of the middle finger because of osteophyte of the metacarpal head. The locking of the MCP joint usually occurred in the older patient as a result of significant osteophyte around the metacarpal head. Unlocking of the MCP joint was done by closed manipulation under local anaesthesia.

Locking of the MCP joint of the finger because of other causes than tenosynovitis has been reported infrequently.

Locking of the MCP joint caused by osteophyte of the head of the metacarpal is characterised by painful loss of extension of the MCP joint without loss of flexion.

We have treated 7 patients who had locking of the MCP joint occurring in the middle finger with an obvious osteophyte of the metacarpal head. Seven patients, 4 women and 3 men, were treated in our Department. None of the patients had a history of trauma to their hands, and in all of them it was the dominant hand which was affected and usually due to powerful full flexion movement of the fingers. The average age was 73.8 years (65 – 81). The duration of locking was from 3 hours to 14 days. All the patients were treated within 30–60 minutes after reporting to our Clinic. The presentation of the patients was extremely similar. In all cases active and passive extension was blocked and they had pain around the finger. Full flexion was possible. The MCP joint was tender around the palmar aspect with slight diffuse swelling around the dorsal aspect.

Radiographs of the MCP showed degenerative changes in all the patients and oblique views demonstrated an osteophyte either on the ulnar or the radial side of the head

Local anaesthetic Lignocaine 1% 5ml was injected in the MCP and around the joint and after 5–10 minutes manipulation was performed, unlocking achieved and the patients straightaway extended and flexed the finger fully. No-one underwent surgical release. Follow-up from 3 to 8 months, average 6 months. No recurrence of the locking.

Akio Minami reported 4 cases of MCP joint locking of the middle finger, treated surgically. Williams classified the locking of the MCP joint in 3 groups. Langenskiold reported 2 cases of intrinsic locking of the MCP due to catching of the collateral ligament on the lateral bony projection of the metacarpal head.

It is very difficult to explain why the middle finger is most likely affected. Kessler noted that the MCP joint seldom participates in a generalised degenerative OA.