Flexor Pollicis Longus Rupture: (Mannerfelt Lesion)

- See: Flexor Pollicis Longus:

- Discussion:
    - rupture of the flexor pollicis longus tendon is common in RA;
    - etiology:
         - rupture of FPL occrus as result of attrition over scaphoid (osteophyte), which had eroded through volar wrist capsule;
         - arises from carpal irregularities, volar synovitis, or volar carpal tunnel subluxation at the carpal tunnel;
    - diff dx:
         - anterior interosseous nerve;
         - trigger thumb
         - IP joint arthritis;

- Exam:
    - carefully note anterior interosseous nerve function (r/o compression);
    - carpal tunnel symptoms may result from proximally displaced tendon edge which has been known to be doubled over itself at entrance of carpal tunnel;
    - patients typically have passive but not active flexion of thumb at IP joint (otherwise consider trigger thumb);
    - if pt has a good IP joint, then the loss is apparent;
    - if there is destruction of the IP joint then the tendon rupture causes little functional loss;

- Radiographs:
    - assess amount of joint destruction of IP, MP, and CMC joints;
    - carpal tunnel view

- Treatment:
    - FPL Advancement and Pull Through:
    - either terminal joint stability or restoration of active motion must be provided;
    - volar aspect of wrist must be explored, to look for a bony spicule that has disrupted
          FPL, since such a spicule might also affect the tendons of the index finger;
    - treatment options include FPL advacement and pull thru, bridge grafts, FDS tendon transfer, or arthrodesis  of PIP joint & synovectomy;
    - if spicule of bone is present, and both ends of the tendons can be identified, then consider a bridge graft;
          - use palmaris longus or FCR;

- Post Op:
    - the thumb and wrist are immobilized for three weeks, before active motion is begun

Laceration of the Flexor Pollicis Longus Tendon: Delayed Repair by Advancement, Free Graft or Direct Suture.  A clincial and experimental study.

Flexor superficialis tendon transfers to the thumb: An alternative to the free tendon graft for treatment of chronic injuries within the digital sheath.

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, April 11, 2012 11:37 am