Patellar Kneecap Dislocation

Overview

The patella, known as the kneecap, makes up the anterior (front) portion of the knee joint. The tendon of the quadriceps (thigh muscle) attaches to the top of the patella, and the patellar tendon attaches to the base of the patella and connects it to the tibia (shin bone). Patellofemoral injuries are a broad range of injuries that cause pain in the front of the knee around the patella. Atraumatic pain over the front of the knee related to overuse is called patellofemoral syndrome, also known as “runner’s knee” because they are often related to overuse and repetitive loading on the patellofemoral joint (activities like running and jumping). Patellofemoral pain is exacerbated after sitting or prolonged knee flexion and is frequently painful with stairs. Nonoperative treatment options resolve the vast majority of patients with patellofemoral syndrome, and are initially recommended to reduce pain and return to normal level of activity. These treatments include physical therapy, activity modification, oral anti-inflammatory medications (NSAIDs), bracing and occasionally steroid injections. Rarely arthroscopic surgery is recommended to relieve pain.

Patellofemoral pain and instability can also result from the patella dislocating from its original position in the joint. This commonly occurs with abrupt twisting or direct trauma. Dislocating the patella leads to sharp pain in the kneecap and if the kneecap does not go back in place on its own, it must be reduced (retuned back to its normal position). Following a patellar dislocation, instability (feelings of the kneecap giving out or re-dislocating) can become recurrent. The majority of primary (first time) patellar dislocations improve with nonoperative treatment, inclusive of activity modification, proper physical therapy, a stabilization brace, and anti-inflammatory medication. In cases of recurrent (more than once) patellar instability, surgical treatment is often recommended to reconstruct the soft tissues or bony problems leading to recurrent patellar instability. Identifying the main cause of patellar instability is important help determine the best surgical solution which can range from a knee arthroscopy and isolated ligament reconstruction to a combined reconstruction and bony realignment procedure.