A prospective randomized study of ACL-reconstructions using bone-patellar tendon-bone grafts fixed with bioabsorbable or metal interference screws

Abstract

IntroductionBioabsorbable screws are, at the expense of metal screws, increasingly used as fixation device in ACL-reconstructions. The possible advantages with bioabsorbable screws are better postoperative MRI evaluations and easier revision surgery.PurposeThe aim of this study was to compare the clinical outcome after ACL-reconstructions with BPTB-grafts fixed with metal interference screws or bioabsorbable screws 7 years postoperatively. The resorption of the bioabsorbable screws was also analyzed.MethodsBetween 2000 and 2001, 41 patients with ACL deficient knees were randomized for the use of BPTB-graft fixed with either metal interference screws or bioabsorbable poly-l-lactic acid screws. This is a 7-year follow-up with clinical examinations of both groups and, MRI of the patients with bioabsorbable screws.ResultsThe clinical and functional results were satisfactory in both groups. There were no significant differences between the groups in any parameter measured, except for better Pivot shift results in the bioscrew group (P = 0.04). The MRI evaluation showed degradation of the bioscrews. A residual screw tract which appeared threaded was seen in the tibia in 11 of the 16 patients. There was no sign of bony ingrowth in the previous screw site in the tibia in any of the patients.ConclusionThe potential advantages of using PLLA-screws compared to metal screws are not sufficient to warrant the routine use of PLLA-screws in ACL-reconstructions.Level of evidenceI.

Bioabsorbable Versus Titanium Screws in Anterior Cruciate Ligament Reconstruction Using Hamstring Autograft

“…Drogset et al 6 reported complete resorption of the PLLA screw on MRI of 16 patients, 7 years after surgery, but the area of the resorbed screw was filled with soft tissue without sign of significant bony ingrowth at the femur or tibia. Moisala et al 17 reported better resorption of the copolymer PDLA-TMC screw on the femoral side and replacement of the screw by soft tissue.…”

“…14 Myers et al 18 showed that identically shaped bioabsorbable (PLLA-HA) and metallic screws were equally successful up to 2 years after 4-stranded hamstring autograft for ACLR on clinical and radiographic assessment, but MRI was not performed. Drogset et al 6 found equivalent satisfactory clinical and functional results with a PLLA screw compared with a titanium screw in bone-patellar tendon-bone ACLR at 7 years. The outcome of ACLR comparing a PLLA-HA screw to a titanium screw with MRI over 5 years has not previously been reported.…”

A novel, hydroxyapatite-based screw-like device for anterior cruciate ligament (ACL) reconstructions

“…In order to ensure a good graft fixation, different extracortical (e.g. sutures, suspension devices, cross pins [1,5,6]), intercortical (interference screws) [7][8][9][10], and combined systems [5] were evolved. The main disadvantages of the extracortical fixation for soft-tissue grafts are the decreased stiffness due to the linkage material and the increased tunnel motion [11], which could interfere with the healing process.…”

Extra-articular and transcutaneous migration of the poly- l / d -lactide interference screw after popliteal tendon reconstruction

“…As disadvantages, metallic screws present the risk of damaging the graft, especially in the case of soft tissue grafts, and making the reconstruction more fragile, as well as turning into artifacts on magnetic resonance imaging and often requiring removal in revision ligament reconstruction surgeries 3, 5, 6, 7. In turn, absorbable screws have as disadvantages the possibility of breakage and migration, as well as inflammatory synovitis.…”