Correlated Research For Shoulder Sports Injury Repairing Using Cortical Bone Anchor

Objective: To evaluate the biomechanical features, histology, clinical research of a self-made cortical bone anchor for shoulder sports injury repairing. Methods: 1,Fresh porcine fresh tibial cortical bone is made to ancipital cortical anchors3.5mm×7.0mm; Ethibond NO.2 non-absorbable suture is pulled through the eyelet for preparation. All the specimens are divided to two groups, in control group the FastinRC metal screw is used. An ancipital cortical anchor and a metal screw are embeded into the area between humerus head and greater tubercle separately in the same specimen. The shaft of humerus is fixed on the work desk using clamp, and the end of suture is hanged on the biomechanical testing machine, the biomechanical pull-out testing is performed. 2, Histology:Sheep were chosen for study, supraspinatus tendon was cut off,and cortical anchor was used to fix free tendon. Imageology and histology were done to study the specimens after 4,8,12 weeks after surgery.3,Clinical research:cortical anchor was made from profound hypothermia and γ handling cortical bone.It was used for rotator cuff repairing and Bankart lesion. Imageology and UCLA,Rowe score were used to evaluate the shoulder function 4,8,12 weeks after surgery. In Results: The failure modes in cortical bone anchor are eyelet failure in 2 cases, suture failure in 1 case, and anchor pullout in 7 cases. The mean failure load is 181.2N. In FastinRC metal screw group the failure modes are suture failure in 2 cases, and anchor pullout in 8 cases. There is no eyelet failure, the mean failure load is 163.8N. There is no statistical difference between the two groups. The mean data of press test in cortical bone anchor is 890.0±124.3N. Histology showed that bound between anchor and cancellated bone became vague,anchor was absorbed completely after 12 weeks.The tendon was healing after 4 weeks. Clinical research showed that patients was satisfied with shoulder function after 12 weeks.Conclusion: Thebiomechanical property of cortical bone anchor reaches the need of initial capability for shoulder sports injury repairing.