Subdivision of flexor tendon "no man's land" and different treatment methods in each sub-zone. A preliminary report

"No man's land" of the flexor tendon system is divided into 4 subdivisions based on our anatomical study. Clinically, a total of 72 flexor tendon injuries in "no man's land" were repaired during the primary and delayed primary stages. Different treatments of flexor tendons, sheath, vincula and postoperative exercises were used according to the degree of injury and anatomical and functional characteristics of each subdivision. The multiple intratendinous suture method, autogenous sheath graft and vincular repair were designed and attempted preliminarily in clinical practice. In 80.4% of the cases, excellent or good results were achieved. Comparison of treatment results in each sub-zone reveals that the IIc sub-zone is the most difficult area for satisfactory functional recovery in "no man's land". The significance of the subdivision of Bunnell's "no man's land" is discussed, and the preoperative assessment method of noting the extent of injury and selection of the treatment method for each sub-zone are presented in this paper. We believe that primary or delayed primary repair can restore good function to the repaired tendons. The effective way of enhancing treatment results of the tendon injury is to apply comprehensive treatment according to the extent of injury to the intrinsic healing capacity of the flexor digitorum profundus tendon.