Successful infiltration of the flexor tendon sheath

Twenty cadaveric fingers and five thumbs were injected through a midaxial approach, a palmar approach superficial to the flexor tendon, and a palmar approach deep to the tendon, to assess the ability of these approaches to infiltrate the flexor tendon sheath successfully. With care to observe proper positioning of the needle, we were able to achieve essentially equivalent success in infiltration with most of these approaches. However, the midaxial approach to the thumb flexor sheath was unsuccessful.