now more susceptible to degradation by tissue collagenases it also keeps the collagenous fibrotic adhesions in a fragile form so that controlled passive mobilization is beneficial it modifies the quality of the now fragile adhesions the risky outcome of hand surgeries involving the flexor tendons actually dissuades some hand surgeons from performing the surgery at all once the peritendinous adhesions are formed and stabilized the tenolysis offers only temporary restoration of the gliding function as the fibrotic tissue regrows within some 2 3 months e e peacock jr was the champion of using systemic administration of bapn in the treatment of peritendinous adhesions in animal models as well in human patients based on several animal experiments he and his coworkers demonstrated a significant improvement in the gliding function of the lacerated tendons in chicken or rats models see peacock and madden surgery 66 215 1969 see also craver madden and peacock annals of surgery 167 697 1968 beneficial effects of bapn in animals were so striking that the same author obtained an ind from fda to use the drug in patients after tenolysis here again he documented a beneficial effect but the dose of bapn 1 2 g day per os was obviously too high inducing several side toxic effects so that the study was discontinued today with the possibility of local administration of the long acting drug in dosages 100 times lower bapn offers new hope to this problem there exist certain similarities in the healing of a nerve and a tendon with the exception that the nerve represents more complex structure and functions most of the collagen in the nerve is in the perineurium this is also the main source of fibrogenic cell.