Lateral Release and Thermal Reefing for Patellar Instability

The results of this study support the use of lateral release and heat treatment of the medial retinaculum for patellar instability. Patients with dislocating kneecaps (patellar instability) were included. This method of treatment avoids extra cuts to open the knee. It also reduces time in the operating room.

The retinaculum on both sides of the kneecap is a band of connective tissue. It helps hold the kneecap in place. As the kneecap goes up and down it must move along a track without sliding to one side or the other.

When present on both sides, the retinaculum keeps the kneecap tracking in the middle. When one side is tighter or looser than the other side the kneecap is more likely to sublux or dislocate causing pain and disability. Usually the lateral (outside edge) retinaculum is tight and pulls the kneecap in that direction.

Treatment was applied using an arthroscope. This tool allows the surgeon to see inside the joint while performing the operation. A thermal (heat) probe was inserted through the arthroscope and used to shrink the retinaculum on the inside edge of the kneecap. The process is called thermal reefing. It tightens up the structures holding the kneecap along the inside edge. The retinaculum along the outside edge of the knee was cut (released).

Patients were followed for at least two years. Pain, function, and patient satisfaction were measures used to assess results. Treatment was successful in 91 percent of the cases. Results were rated as good to excellent for this group. Five of the 62 knees were considered failures with one (or more) dislocations.

The authors conclude that lateral release and thermal reefing is just as good as other methods of treating patellar instability. A rehab program that works within the time frame of healing tissue must be a part of the recovery process. Return to sports must be monitored closely.