Crosslinked Anisotropic Xenogeneic Diaphragm Tissue in Flexor Tendon Pulley Reconstruction

By way of illustration, and not of limitation, a simple example of the present invention is given, with the caution that adaptations and adjustments may be made without departing from the invention. Fresh bovine or porcine diaphragm tissue is received from the slaughter house, inspected to meet vendor specifications, and thoroughly rinsed in pH 7.4 phosphate buffered solution. The diaphragm tissue is dissected, separating and discarding all fat tissue and extraneous connective tissue and blood vessels, to leave only a smooth serous side and a fibrous side. The fibrous side is thinned down to a maximum of 0.5 mm using pathology scalpels. The dissected tissue is cut into smaller pieces of usable areas. This tissue is submerged in a suitable container of 0.2% phosphate buffered glutaraldehyde pH 7.4 and kept at room temperature. The submerged tissue is laid flat in the container and left unstressed. The container is kept closed to eliminate the possiblilty of contamination to the tissues, and Good Laboratory Practice Regulations and Good Manufacturing Practice Regulations are followed at all phases of the process. After 24 hours has elapsed, the tissue is turned and the solution discarded and fresh 0.2% buffered glutaraldehyde is added until the tissue is completely submerged. This procedure is repeated at 48 and 72 hours. After 72 to 96 hours, samples of the crosslinked tissue are tested using standard Shrinkage Temperature testing apparatus and procedures to assure adequate crosslinking. The crosslinked tissue is aseptically dissected to final configuration under sterile environment, such as, for example, a Class 100 Laminar Flow Bench. The final configuration of the pulley replacement material should normally be about 10 mm wide, 20 mm long and 0.3 to 04. mm thick, though the exact dimensions will depend upon the particular patient and procedure for which the tissue is being prepared. Dimensioning is accomplished using a fine scalpel for dissection to meet particular size requirements. In preparing tissues for sale or distribution, a series of tissues ranging from about 7 mm.times.12 mm to about 15 mm.times.30 mm in width and length are prepared thus permitting the surgeon to select the appropriate size. The surgeon can, of course, modify a given size to meet a particular requirement as determined during surgery. The tissue is inspected by Quality Assurance to assure compliance with all specifications, packaged in an approved container of sterile physiologic saline and radiation sterilized.

The biocompatable cross linked bovine or porcine or other anisotropic mammalian diaphragm allows host connective tissue to ingrow the outer fibrous layer while the inner smooth layer allows unobstructed gliding of the flexor tendon with minimal adhesion formation. The method of this invention si simplified because of the ease of surgical implant. The result of the surgery performed in accordance with this invention is superior to known prior art methods because of the characteristics of the crosslinked, anisotropic mammalin diaphragm, which is characterized in that it has a smooth serous side riding against the tendon providing a high strength wear and degradation resistant surface to protect and permit movement of the flexor tendon, and a rough or fibrous side which promotes tissue in-growth into the fibrous side of the diaphragm material thereby increasing the compliance and performance of the reconstructd pulley.

The tissues of the invention are suitable for shipment and sale as human implants.