Synovial cyst of the pulp of the little finger--origin from the wrist joint.

Synovial cysts of the pulp of the little finger in three elderly patients were shown by arthrography to arise from leakage of synovial fluid from the wrist joint into the ulnar bursa and thence into the flexor synovial sheath in the digit. Distant as well as local sources of the contents of synovial cysts should be considered when the local anatomy permits communication between a degenerate joint and an adjacent tendon sheath.