Patellar Tendon ACL Reconstruction
When the ACL (anterior cruciate ligament) is torn or incompetent, it can allow your knee to shift or buckle, particularly with twisting or cutting maneuvers. When the anterior cruciate ligament is completely torn, which is the case in approximately 95% of ACL injuries, it has little ability to heal and therefore, a new ligament must be created. There are a number of substitutes (grafts) available to replace and serve as the new ACL. The central 1/3 of the patellar tendon (which connects the kneecap [patella] to the upper end of the lower leg bone [tibia]) is a frequently used substitute for the damaged ACL. It is often the preferred graft for young, competitive athletes involved in aggressive cutting or pivoting maneuvers such as soccer, basketball, or football. It may also be recommended when the knee injury and laxity are chronic (> 4 – 6 months) or when multiple ligaments are damaged, resulting in knee laxity in multiple planes. Additional ligament repair may be necessary for the associated laxity of other knee ligaments. After the graft is harvested, the remaining ligament gradually thickens and gets stronger. Once the graft is removed, the bone plugs (10 mm X 22 mm in size) are shaped into a cylindrical configuration and two small drill holes are created in the plugs for passing sutures. One drill hole is created in the upper end of the tibia and a second one in the lower end of the thighbone (femur). These tunnels are placed at the exact attachment sites for the normal ACL. The graft is then passed into the tunnels and secured at either end. The new ligament passes along the same course as your normal ACL did. Physical therapy to restore knee motion, leg strength, and agility is prescribed. Rehabilitation and recovery of full activities generally require 7 – 9 months.