Flexor Pulley Repair / Reconstruction 

- See:
     - Prosthetic Grafts
     - Flexor Tendon Sheath Anatomy
     - Staged Tendon Reconstruction

- Discussion:
     - the A2 and A4 pulleys are essential to prevent flexor tendon bow stringing;
     - inadequate pulley reconstruction will lead to bowstringing of the flexor tendon;
     - include use of a portion of FDS, free tendon graft, or extensor retinaculum;
     - reconstruction is performed to a remnant of the destroyed pulley, thru bone holes, or encircling the phalanx;
     - pulleys should not be built at the same time as direct repair, tendon grafting, or tenolysis because early active motion may stretch annular pulley
              reconstruction and because adhesion formation bewteen these structures is likely;
              - generally only staged tendon reconstruction can be performed along with pulley reconstruction;

- Techniques:
     - consider using the resected flexor tendon for pulley reconstruction;
     - any technique used, must allow for revision of flexor pulley, as pulley may be applied too tightly or too loosely as seen on post op x-rays;
           - generally, the reconstructed pulley should be snug;
           - on x-ray, if rods are seen to bowstring, then the pulleys are too loose;
           - on x-ray, if rods are seen to buckle, then the pulleys are too tight;
     - generally, a reconstructed A2 and A4 pulley will require two loops of bridging tendon segments for adequate repair;
     - one technique involves, anchoring a short segment of resected flexor tendon to one side of either the proximal or distal phalanx (using bone anchors);
           - on the opposite side of the digit, one end of a flexor tendon segment is anchored to bone, w/ other end of the tendon segment brought over
                      flexor tendon (or prosthetic rod) and secured to a segment of previously anchored tendon segment;
           - if the pulley tension needs to be adjusted, the tendon-tendon segment interface can be freed and the pulley tension re-adjusted;

- Post Operative Care:
    - external pulley rings may limit tendon bowstringing









- A2 pulley Release or Reconstruction:
       - references:
                   - The "turtleneck" pulley plasty for finger flexor tendon repair.
                   - Feasibility of partial A2 and A4 pulley excision: effect on finger flexor tendon biomechanics.
                   - The second annular pulley: a histologic examination  
                   - The effect of partial A2 pulley excision on gliding resistance and pulley strength in vitro.
                   - "Venting" or partial lateral release of the A2 and A4 pulleys after repair of zone 2 flexor tendon injuries. 
                   - Flexor tendon pulley V-Y plasty: an alternative to pulley venting or resection
                   - A2 pulley incision or one slip of the superficialis improves flexor tendon repairs.
                   - Three-loop technique for A2 pulley reconstruction.
                   - The Effect of Pulley Recon on Flexion, Bowstringing, and Gliding in the Setting of Zone II Repair of FDS and FDP: a Cadaveric Investigation.
                   - Flexor digitorum superficialis repair outside the A2 pulley after zone II laceration: gliding and bowstringing.
                   - Pulley plasty versus resection of one slip of FDS after repair of both flexor tendons in zone II: a biomechanical study.
                   - Resection of the flexor digitorum superficialis reduces gliding resistance after zone II flexor digitorum profundus repair in vitro.
                   - The direct midlateral approach with lateral enlargement of the pulley system for repair of flexor tendons in fingers.
                   - Zone 2 FDP and Superficialis Rupture Treated With Single-stage Tendon Reconstruction Using an Active Hunter Rod Implant  

- A4 pulley Release or Reconstruction:
       - references:
                   - Quantification of partial or complete A4 pulley release with FDP repair in cadaveric tendons 
                   - The flexor digitorum profundus "demi-tendon"--a new technique for passage of the flexor profundus tendon through the A4 pulley.
                   - Release of the A4 Pulley to Facilitate Zone II Flexor Tendon Repair  
                   - Modified flexor digitorum superficialis slip technique for A4 pulley reconstruction.



A mechanical study of six digital pulley reconstruction techniques. Part I. Mechanical effectiveness.

Reconstruction of the flexor pulley. The effect of the tension and source ofthe graft in an in vivo dog model.
   
Use of vein graft as a tendon sheath substitute following tendon repair: an innovative technique in tendon surgery.

Results of primary tendon repair with closure of the tendon sheath.

Flexor tendon repair and rehabilitation in zone II open sheath technique versus closed sheath technique

The Omega "Omega" pulley plasty. A new technique to increase the diameter of the annular flexor digital pulleys

Primary pulley enlargement in zone 2 by incision and repair with an extensor retinaculum graft.




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

Last updated by Clifford R. Wheeless, III, MD on Thursday, July 9, 2015 2:27 pm