Chronic patellar instability explained

It may follow a previous dislocation or reflect a combination of ligament injury, limb alignment, kneecap shape and muscle control. An assessment helps identify which factors are relevant before treatment is selected.

The patella normally glides in a groove at the end of the thigh bone as the knee bends. Stability comes from bone shape, supporting ligaments and coordinated muscles. After dislocation, the inner restraint may be stretched or torn, while swelling and loss of strength can further reduce control.

Patellar instability commonly presents with a sensation that the kneecap is slipping, especially during turning, landing, stairs or rising from a deep bend. Some episodes are partial shifts rather than a visibly displaced kneecap. Repeated events can irritate or injure joint cartilage.

Early management often addresses swelling, comfortable knee motion, hip and thigh strength, balance, landing control and gradual return to activity. A brace may support confidence during selected activities, but fitting and duration should match the individual knee.

An orthopedic review is useful after repeated dislocations, ongoing apprehension or failure to regain function. Examination and imaging can assess alignment, cartilage, the stabilising ligament and groove shape. Surgery may be considered when recurrent instability persists; the chosen procedure depends on the underlying anatomy rather than symptoms alone.

Seek urgent care if the kneecap remains visibly out of place, the knee looks deformed, or the foot becomes numb, pale or cold. Do not force the kneecap back yourself. Rapid swelling after a twist, inability to bear weight, locking, or severe pain also warrants prompt evaluation for cartilage, bone or ligament injury.

Ask which anatomical and movement factors contribute to instability, whether cartilage was injured, and what milestones should guide return to sport. If an operation is proposed, clarify which structure it addresses, the expected rehabilitation stages, and restrictions for work or driving.