Arnulf Stenzl á Hannes Strasser á GuÈnther Klima Iris Eder á Ferdinand Frauscher á Helmut Klocker Georg Bartsch á Milomir Ninkovic Reconstruction of the lower urinary tract using autologous muscle transfer and cell seeding: current status and future perspectives Abstract Functioning free-muscle transfer has estab- lished itself for the treatment of skeletal muscle de®- ciency over the last two decades. The capability of skeletal muscle to empty a spherical reservoir has been shown to be lessened if the muscle has contracted due to dissection. Currently there is no established curative treatment for bladder acontractility. Experimental data and preliminary clinical results have shown that inner- vated free latissimus dorsi muscle (LD) may serve as a substitute for a dysfunctional detrusor. In a clinical protocol, latissimus dorsi detrusor myoplasty (LDDM) was applied in 11 patients (age 9±68 years) with bladder acontractility due to spinal cord injury (seven patients), congenital malformations (two patients), detrusor my- opathy (one patient), and idiopathic causes (one patient) who had required catheterization for bladder emptying for a minimum of 2 years. In all, 10 of 11 patients were capable of voiding volitionally, with eight of them no longer requiring catheterization, throughout the follow- up period of 12±46 months. Transplanted LD activity was con®rmed by ultrasonography and ¯ow-mode computerized tomography. It can thus be concluded that emptying of the bladder can be induced through the contractility of reinnervated free LD that has been wrapped around the bladder. An innervated free-LD ¯ap does not undergo the severe muscle ®brosis, con- tracture, and atrophy that occur after transfer of com- pletely or partially denervated pedicled muscle. Apart from the restoration of de®cient detrusor function, mi- croneurovascular transfer of a free-LD ¯ap may be combined with tissue engineering to serve as a basis for bladder augmentation and substitution. Key words Free ¯ap á Functioning muscle transplantation á Urinary bladder á Detrusor acontractility á Tissue engineering á Detrusor myoplasty á Latissimus dorsi muscle Until recently, skeletal muscle had been used in the urinary tract mainly to cover large traumatic or radio- genic defects with well-vascularized tissue. In 1970, Tamai et al. [23] reported on their experiments using free functioning-muscle transfer for the functional replace- ment of skeletal muscle. In subsequent years this tech- nique was successfully used in the clinical setting for restoration of facial nerve aicted with palsy [9] and for muscle de®ciency of the extremities [12]. A recent study has also shown that free functioning-muscle transfer can be a valuable reconstructive procedure in patients with a signi®cant functional de®cit in the abdominal-wall musculature [12, 17]. The gracilis, latissimus dorsi (LD), and gastro- cnemius muscles [2, 15] are the muscle tissues most fre- quently used for functional transplantation. Such muscle transfer has always been used to correct a malfunction of other skeletal muscles. The use of a pedicled LD ¯ap to support heart function [4] in selected patients pre- senting with severe cardiopathy was the ®rst attempt at functional substitution of nonskeletal muscle with skel- etal muscle. We went a step further by using free-skel- etal-muscle transfer as a substitute for the nonfunctioning bladder detrusor, ®rst experimentally and, in a more recent series, also clinically. World J Urol (2000) 18: 44±50 Ó Springer-Verlag 2000 A. Stenzl (&) á H. Strasser á I. Eder á H. Klocker á G. Bartsch Department of Urology, University of Innsbruck Medical Center, Anichstrasse 35, A-6020 Innsbruck, Austria e-mail: arnulf.stenzl@uibk.ac.at, Tel.: +43-512-5044813, Fax: +43-512-5048411 M. Ninkovic Department of Plastic and Reconstructive Surgery, University of Innsbruck Medical Center, Innsbruck, Austria G. Klima Institute of Histology, University of Innsbruck, Innsbruck, Austria F. Frauscher Department of Radiology II, University of Innsbruck Medical Center, Innsbruck, Austria