Finding your footing around patellar instability

Patellar instability is a condition that affects the kneecap (patella), causing it to move out of its normal position. This can result in pain, loss of function, and an increased risk of further injury. It is especially common in younger, active individuals, but it can affect people of all ages. Early recognition and appropriate management are key to preventing long-term damage. In this article, consultant orthopaedic surgeon Mr Muhammad Adeel Akhtar explains the signs of patellar instability and what can be done to manage it.

What is patellar instability?

The patella normally sits in a groove at the front of the thigh bone (femur) and moves smoothly as the knee bends and straightens. In cases of patellar instability, the kneecap becomes prone to shifting out of place, most often dislocating to the outer side of the knee.

This can happen as a result of:

Direct trauma, such as a blow to the knee during sports.
Sudden twisting movements, especially if the foot is planted and the body turns.
Congenital factors, such as a shallow femoral groove, generalised joint hypermobility, or abnormal alignment of the leg.

Once the patella has dislocated once, the risk of recurrent instability increases, particularly if the underlying structural issues are not addressed.

Symptoms of patellar instability

The symptoms of patellar instability can vary depending on the severity and frequency of the dislocations. Common signs include:

A sensation of the kneecap slipping or giving way, especially during twisting or pivoting movements.
Visible dislocation, where the kneecap is clearly out of place, which often requires manual relocation or popping back spontaneously.
Pain and swelling following a dislocation or subluxation (partial dislocation).
Tenderness along the front of the knee, particularly over the inner border of the patella.
Fear or apprehension when straightening the knee or bearing weight after an episode.

In some cases, individuals may also notice reduced muscle strength, stiffness, or difficulties with normal activities such as walking, climbing stairs, or standing from a seated position.

Risks of untreated patellar instability

If left untreated, recurrent patellar instability can lead to a number of long-term issues, including:

Damage to the cartilage behind the kneecap, increasing the risk of osteoarthritis.
Ongoing pain and reduced function, which can limit physical activity and overall mobility.
Muscle weakness and imbalance, particularly in the quadriceps and surrounding muscles.
A higher risk of further dislocations, sometimes with less force or trauma than the original event.

Chronic instability can significantly impact quality of life, particularly for active individuals or those involved in sport. Early assessment and treatment can help prevent these complications.

How to treat patellar instability

The treatment approach depends on the severity of the instability, the number of dislocations, and individual patient factors.

Conservative management

Following a first-time dislocation, initial treatment should focus on rest, ice, compression and elevation (RICE). Over-the-counter pain relief, such as paracetamol or ibuprofen, can help manage discomfort. Once swelling reduces, gentle range-of-motion exercises may be started under guidance.

In many cases, physiotherapy is the cornerstone of treatment. A structured rehabilitation programme aims to strengthen the muscles in the hips and legs to better support the kneecap, and restore flexibility and balance control to prevent further injury. Bracing, taping, or crutches may also be recommended to provide additional support during movement.

Surgical options

Surgery may be considered for those with recurrent dislocations, failed conservative treatment, or clear structural abnormalities. Common procedures include:

Medial patellofemoral ligament reconstruction, which rebuilds the ligament that stabilises the inner side of the kneecap.
Realignment surgery, such as tibial tubercle transfer, to correct the pull of the patellar tendon.
Arthroscopy, to remove loose fragments or repair cartilage damage.

Surgical treatment is often followed by a period of rehabilitation, and most patients can return to sport or normal activities once strength and stability have been restored.