What is Tibial Tubercle Osteotomy?
Tibial tubercle osteotomy is a surgical procedure that is performed along with other procedures to treat patellar instability, patellofemoral pain, and osteoarthritis. The tibial tubercle transfer technique involves realignment of the tibial tubercle (a bump in the front of the shinbone) such that the kneecap (patella) traverses in the centre of the femoral groove. The patellar maltracking is corrected by moving the tibial tubercle medially, towards the inside of the leg. This removes the load off the painful portions of the kneecap and reduces pain.
Indications of Tibial Tubercle Osteotomy
Surgical treatment is indicated when physical therapy and other non-surgical methods have failed and there is a history of multiple knee dislocations.
Tibial Tubercle Osteotomy Procedure
The procedure is performed under general anaesthesia. At first, an arthroscope will be inserted to inspect the inside of the knee joint. It involves small incisions or portals through which small instruments are passed and a video camera is used to visualize the anatomy of the knee joint, evaluate patella cartilage and assess patella tracking.
Tibial tubercle osteotomy and transfer are done through an incision made in the front of your leg, just below the patella. In an osteotomy, a periosteal incision of 8-10 cm is made at 1 cm medial to the tibial tubercle. With the help of an oscillating saw, a cut is made medial and distal to the tuberosity. The tapered design of the distal cut avoids the risk of a tibial fracture.
Similarly, a proximal cut is made using appropriate instruments such as a curved osteotome or reciprocating saw. Then, an osteotomy through the bone cortex is performed without cutting the lateral periosteum. The lateral periosteum serves as a point of attachment for the osteotomy segment. By doing this, a tibial tubercle segment, which is more than 2 cm in width, more than 1 cm in thickness and 8-10 cm in length can be obtained. It should include all portions of insertion of the patellar tendon. The segment from the tibia is then levered using the osteotome to provide access to the medullary canal of the tibia.
The osteotomy segment is then moved under direct vision into a position that assures proper tracking of the patella. The tracking pattern can be confirmed arthroscopically. The mobilized bone is then fixed into its new place using screws, which can be removed later if they cause irritation.
Post-surgical Care for Tibial Tubercle Osteotomy
You may have minimal-to-moderate knee discomfort for several days or weeks after the surgery. Oral pain medications will be prescribed. Keep the operated leg elevated and apply an ice bag over the area for 20 minutes. This decreases swelling as well as pain. You may have to wear a leg brace that may be removed only while sitting with your leg elevated and when using the continuous passive motion (CPM) unit. Physical therapy exercises should be performed as it helps in regaining mobility. Eat healthy food and drink plenty of water.
Risks and Complications of Tibial Tubercle Osteotomy
This is quite a safe procedure and provides excellent access and surgical exposure during a difficult primary or revision total knee arthroplasty. Risks following tibial tubercle osteotomy surgery are rare, but may include compartment syndrome, deep vein thrombosis, infections and delayed bone healing.