Reconstruction of the lower urinary tract using autologous muscle transferand cell seeding: current status and future perspectives

Functioning free-muscle transfer has established itself for the treatment o f skeletal muscle deficiency over the last two decades. The capability of s keletal muscle to empty a spherical reservoir has been shown to be lessened if the muscle has contracted due to dissection. Currently there is no esta blished curative treatment for bladder acontractility. Experimental data an d preliminary clinical results have shown that innervated free latissimus d orsi muscle (LD) may serve as a substitute for a dysfunctional detrusor. In a clinical protocol, latissimus dorsi detrusor myoplasty (LDDM) was applie d in 11 patients (age 9-68 years) with bladder acontractility due to spinal cord injury (seven patients), congenital malformations (two patients), det rusor myopathy (one patient), and idiopathic causes (one patient) who had r equired catheterization for bladder emptying for a minimum of 2 years. In a ll, 10 of 11 patients were capable of voiding volitionally, with eight of t hem no longer requiring catheterization, throughout the follow-up period of 12-46 months. Transplanted LD activity was confirmed by ultrasonography an d flow-mode computerized tomography. It can thus be concluded that emptying of the bladder can be induced through the contractility of reinnervated fr ee LD that has been wrapped around the bladder. An innervated free-LD flap does not undergo the severe muscle fibrosis, contracture. and atrophy that occur after transfer of completely or partially denervated pedicled muscle. Apart from the restoration of deficient detrusor function, microneurovascu lar transfer of a froe-LD flap may be combined with tissue engineering to s erve as a basis for bladder augmentation and substitution.