Ligaments, artificial

Most of the studies on PLA degradation have concentrated on abiotic hydrolysis [35-37]. The effects of, e.g., residual monomer and other impurities, molecular weight and copolymerization on hydrolysis rate and properties have been studied [3,37-42]. Impurities, residual monomer [43,44], and peroxide modification [45] all increase the hydrolysis rate, while copolymerization can either increase (GA-copolymers) or decrease (CL, DXO-copolymers) the hydrolysis rate. Degradation of PLA and its copolymers in clinical applications ranging from absorbable sutures to drug delivery systems and artificial ligaments has also been widely studied [46-48]. 

Porous materials used in soft tissue applications include polyurethane, polyamide, and polyester velours used in percutaneous devices. Porous reconstituted coUagen has been used in artificial skin, and braided polypropylene has been used in artificial ligaments. As in the case of bone implants, the porosity encourages tissue ingrowth which anchors the device. 

Implantable materials are used in effecting a repair to the body, be it wound closure (sutures) or replacement surgery (vascular grafts, artificial ligaments, etc.). Table 5.4 illustrates the range of specific products employed within this category, with the type of materials and methods of manufacture. Biocompatibility is of prime importance if... 

Textile materials are used in a wide variety of applications in healthcare and medicine which include implantable materials for in vivo applications. Vascular grafts, artificial ligaments, artificial blood vessels and mesh gra are typical implantable medical devices. High-tech advances in tissue engineering have enabled researchers to cultivate implantable hiunan organs to the required shape by growing living cells on textile sc olds. 

Meanwhile, Olson et al., with a rabbit model, tried to explain the role of the artificial ligament in the pathogenesis of osteoarthritis, well known to be a wear mechanism. The wear particles induce the production of significant levels of neutral proteinases (coUagenases and gelatinases) by synovial cells and chondrocytes activating factors. The substrate of those enzymes is actually the molecular architecture of the articular cartilage. Consequently,... 

Olson EJ, Kang JD, Fn FH, Georgescn HI, Mason GC and Evans CH. The biochemical and histological effects of artificial ligament wear particles in vitro and in vivo stndies. Am J Sports Med. 1988 16 558-570. 

Fujikawa K, Iseki F, Tomatsu T, Takeda T and Seedhom BB. Microscopic and histologic findings after reconstruction of the anterior crudate ligament by the Leeds-Keio artificial ligament. Knee. 1984 10 35—40. 

Rading J and Peterson L. Clinical experience with the Leeds-Keio artificial ligament in anterior cruciate Ugament reconstruction. A prospective two-year follow-up study. Am J Sports Med. 1995 23 316-319. 

Lavoie P, Fletcher J and Duval N. Patient satisfaction needs as related to knee stability and objective findings after ACL reconstruction using the LARS artificial ligament. Knee. 2000 1 157-163. 

Nau T, Lavoie P and Duval N. A new generation of artificial ligament in reconstruction of the anterior cruciate ligament. Two-year follow-up of a randomised trial. J Bone Joint Surg Br. 2002 84 356-360. 

Klein W and Jensen KU. Synovitis and artificial ligaments. Arthroscopy. 1992 8 116-124. 

Situations regarding previous femoral tunnels are classified into the following six categories (1) nonanatomic anteriorly created femoral tuimels regardless of the procedures, (2) obviously expanded femoral tunnel by artificial ligament recmi-struction, (3) less expanded femoral tunnel by artificial ligament reconstraction, (4) anatomic single-bundle reconstruction, (5) anatomic double-bundle recmistruc-tion, and (6) BTB reconstruction. How to create femoral tunnel is indicated based on each femoral tunnel situation. It is better to create the femoral tunnel in the fresh bone that does not communicate a previous tunnel with the tendon. 

Obviously Expanded Femoral Tunnel by Artificial Ligament Reconstruction... 

When the previous reconstruction with an artificial ligament results in significant expansion of the tunnel, two-stage surgery could be considered to prevent the new... 

Several known and commonly used biomedical polymers are categorised under the USP Class VI classifications. This includes polytetrafluoroethylene (Pl FE) (used in artificial ligaments and grafts and as catheter liners), fluorinated ethylene propylene (FEP) (used in electrocautery devices and fusing sleeves), PEEK (used in implantables, orthopaedic and dental devices). For Class VI materials, as defined by the USP, the most stringent testing procedures are performed. Any substance that may have leaked from the material is usually captured in extract solutions of NaCl, 5% EtOH, cotton-seed oil or polyethylene glycol. 

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