A Patellar dislocation is characterized by displacement of the patella (knee cap) and tearing of the connective tissue surrounding the patella.
The patella is located at the front of the knee and lies within a groove at the front of the femur (thigh bone). The tendon of the quadriceps muscle (the muscle at the front of the thigh) wraps the patella and attaches to the top end of the tibia (shin bone). Connective tissue called the patella retinaculum attaches the knee cap in place upon the femur. Occasionally the patella may be forced out of its normal position, known as a patellar dislocation.
What are the symptoms of a patellar dislocation?
Typically, a patellar dislocation presents as a sudden, intense pain at the front of the knee during injury. Pain is usually associated with the feeling that the knee is going to ‘give way’ or the feeling of something ‘popping out’. There may be a visible deformity of the knee compared to the unaffected side. There may be a rapid onset of knee swelling within the first 1-2 hours following injury. Once the patella has returned to its original position following dislocation, individuals typically experience an ache that may increase to a sharper pain with movement. Pain is generally experienced during activities that bend or straighten the knee particularly whilst weight bearing. For example, going up and down stairs or hills, squatting, lunging, running or jumping. The borders of the patella may be tender to touch. Patients may also notice a clicking or grinding sound when bending or straightening the knee.
How can physiotherapy help?
Seeking physiotherapy assessment and treatment following a patellar dislocation is crucial. Treatment from a physiotherapist following a patellar dislocation may include soft tissue massage, taping/ bracing, acupuncture, ice or heat treatment, mobilisation and exercise prescription to address any flexibility strength or balance issues with the intent to reduce symptoms. The physiotherapist will also consider that there are several factors which can predispose patients to patellar dislocations, they may address the cause. For example, muscle tightness/weakness, hypermobility (excess movement), having a shallow femoral groove, biomechanical abnormalities, poor technique, poor balance and more.
What causes a patellar dislocation?
A patellar dislocation happens when the kneecap slips out of its groove, usually towards the outer side of the knee. It is often caused by a twisting movement or a direct blow, and some people are more prone to it due to the shape of their knee or greater joint flexibility.
- A sudden twist or change of direction
- A direct knock to the knee
- Naturally looser joints or a shallow kneecap groove
How long does recovery take?
After a first dislocation, the knee usually settles over six to twelve weeks with physiotherapy focused on restoring strength and control. Rehabilitation is important to reduce the risk of it happening again, which is common without proper strengthening.
What you can do at home
- Settle early swelling with ice and relative rest
- Avoid deep bending and twisting while it is painful
- Follow your prescribed strengthening programme closely
Check with your physiotherapist before returning to sport.
Frequently asked questions about patellar dislocation
Will my kneecap dislocate again?
It can, especially without rehabilitation. A structured strengthening programme significantly reduces the risk of a repeat dislocation.
Do I need surgery?
Most first-time dislocations are managed without surgery. Surgery is usually considered for recurrent dislocations or when other structures are damaged.
Where can I get knee rehab on the North Shore?
Dynamic Physio provides knee rehabilitation at our Mairangi Bay, Long Bay and Milford clinics, and our physiotherapists are ACC-registered.