A lateral release is a surgical procedure performed on the knee to address pain and instability affecting the kneecap (patella). This operation is designed to alleviate pressure and improve the patella’s movement as the knee bends and straightens. The process involves cutting a tight band of tissue on the outside of the kneecap to allow it to shift back into its proper alignment within the trochlear groove of the thigh bone. This intervention is typically considered when non-surgical treatments have failed to provide relief for chronic knee discomfort.
What Causes Excessive Lateral Knee Pressure
The primary reason a lateral release becomes necessary is patellar maltracking, where the kneecap is pulled too far toward the outside of the knee joint. This misalignment is often caused by a tightening of the lateral retinaculum, a thick band of connective tissue on the outer side of the patella. This tightening constantly pulls the kneecap laterally, preventing it from gliding centrally and causing it to rub against the femur bone.
This friction and pressure can lead to patellofemoral pain syndrome or lateral patellar compression syndrome. Over time, the excessive pressure can cause irritation and cartilage wear (chondromalacia). Muscle imbalance further contributes to this issue, as weakness in the vastus medialis obliquus (VMO) allows stronger lateral structures to dominate the pull on the patella.
How the Lateral Release Procedure is Performed
The lateral release procedure is most often performed using an arthroscope, a minimally invasive technique utilizing small incisions and a tiny camera. The surgeon typically makes two or three small punctures (portals) around the knee to insert the camera and specialized surgical instruments. The arthroscope projects images onto a monitor, allowing the surgeon to visualize the tight lateral retinaculum with precision. The surgeon then uses an instrument, often a radiofrequency probe or specialized scissors, to carefully cut the lateral retinaculum tissue. This release is performed on the inside of the knee joint capsule, cutting only enough tissue to reduce the excessive lateral tension. Before closing the small incisions, the surgeon tests the patella’s movement to ensure it is tracking correctly and is stable in its newly centralized position.
Recovery and Post-Operative Care
Recovery from a lateral release begins immediately after the procedure, focusing on managing swelling and initiating early movement. Patients are typically instructed to keep the leg elevated above heart level, especially for the first 24 to 48 hours, and to apply ice frequently to minimize swelling and pain. Pain medication is prescribed to control discomfort, though patients are encouraged to transition to non-narcotic options quickly.
Physical therapy (PT) is a major component of the post-operative plan and usually begins within the first week following surgery. The initial focus of PT is on regaining full range of motion, particularly achieving full extension, and performing gentle exercises like quadriceps sets and straight leg raises. Patients typically use crutches for partial weight-bearing for about two to three weeks until they can walk with a normal, pain-free gait. Returning to full daily activities usually takes around three months, although maximal recovery and strength gains can continue for up to a year.