Calcium phosphate coating on tendons via concentrated simulated body fluid soaking

The regeneration of the tendon to bone insertion site affects how well the ACL heals. The addition of a calcium phosphate coating to a tendon graft can help to promote osteointegration and healing of the insertion. Patellar tendons were harvested from neonatal bovines and coated in semi-crystalline calcium phosphate. The tendons were subjected to two 5× concentrated simulated body fluid solutions to layer first an amorphous calcium phosphate coating, followed by a semi-crystalline layer. X-ray diffraction confirms the resultant coating to be similar to hydroxyapatite, which is the mineral phase found in bone. Tensile mechanical testing shows no effect on the ultimate tensile strength of tendons coated in semi-crystalline calcium phosphate. The similarities of the coating to the mineral found in natural bone as well as negligible effects of the coating on the mechanical strength of the tendon give the grafts potential for use in repair of the tendon to bone insertion site.