An anatomic study of flexor tendon sheaths: a cadaveric study.

Previous descriptions of the pattern of communication between the digital flexor tendon sheaths have been largely based on imaging studies. An anatomic study on 12 cadaveric hands was conducted using water soluble dye and directly observed patterns of communication between the digital flexor tendon sheaths and the radial and ulnar bursae. Four out of twelve specimens (33%) demonstrated a communication between the radial and ulnar bursae. The ulnar bursa communicated with the ring finger flexor sheath in two specimens, and the index finger flexor sheath in two specimens. One hand (8.3%) showed communication between the middle finger tendon sheath and radial bursa and between the index finger flexor tendon sheath and radial bursa. These findings show a considerable level of variation in communicating patterns between the synovial sheaths of the hand and wrist. Clinicians should be aware of the possibility of variations to the classical presentation of spread of infection through the digital flexor sheaths.