KNEE SURGERY GLASGOW
Patella Instability
What is patellofemoral instability?
Patellofemoral instability occurs when the kneecap (patella) does not stay properly aligned in its groove at the front of the thighbone (femur). This can cause the kneecap to slip partially (subluxation) or completely dislocate. Instability may happen after a first-time injury, or develop gradually due to anatomical factors or muscle imbalance.
General Overview
The kneecap plays a key role in knee function, helping the thigh muscles straighten the leg. If the patella is unstable, it can cause pain, swelling, and difficulty with activities like running, squatting, or climbing stairs.
Patellofemoral instability is more common in young, active individuals and may recur after the first dislocation. Treatment aims to restore stability, prevent further dislocations, and reduce the risk of long-term problems such as arthritis.
What are the symptoms of patellofemoral instability?
A sudden feeling that the kneecap has “slipped out of place”
Visible kneecap dislocation (often to the outside of the knee)
Pain and swelling after the event
Recurrent episodes of “giving way” or partial dislocation (subluxation)
Difficulty with sports or activities that involve twisting, jumping, or kneeling
Ongoing discomfort or grinding sensation at the front of the knee
How do you treat patellofemoral instability?
First-time dislocation management:
PRICE measures (Protection, Rest, Ice, Compression, Elevation) to reduce pain and swelling
A knee brace or taping to stabilise the patella in the early stages
Physiotherapy to strengthen the quadriceps (especially the inner thigh muscle — vastus medialis) and improve hip/core control
Recurrent instability:
Ongoing physiotherapy and activity modification are first-line treatments
Surgery may be considered if instability continues despite rehabilitation. Common procedures include:
MPFL reconstruction (rebuilding the ligament that holds the patella in place)
Realignment surgery in cases with significant anatomical abnormalities
Your Recovery:
Physiotherapy-based recovery may take 6–12 weeks before resuming sport
After surgery, recovery is usually longer (4–6 months), with a focus on regaining strength, stability, and confidence in the knee
