Why does my knee keep ‘giving way’?

Common patient complaints

As a Consultant Orthopaedic and Knee Surgeon I have treated a number of patients with difficult knee conditions.

A common complaint that affects many of my patients is the feeling of the ‘knee giving way’ which can often occur unexpectedly and cause instability and pain. Each of the following patients presented me with a history of an unstable knee, but the underlying problem in each is different. 

Scenario 1: a sports injury

A 25 year old Ski Instructor attended my Knee Clinic and explained how on numerous occasions she had fallen in the snow whilst skiing.  The bindings on her skis had not come off and as a result she felt immediate pain in her knee.  She started to then experience her knee giving way from time to time especially on a twisting movement. 


The Ski Instructor had sustained a cruciate ligament rupture.  The Anterior Cruciate Ligament (ACL) is a key primary stabiliser of the knee joint.  It prevents the knee giving way when the leg rotates outwards during pivoting and sporting movements.  Injuries to the anterior cruciate ligament can occur during various sporting activities and in particular in sports such as skiing, football and rugby.  This injury is sometimes associated with tears within the cartilage of the knee, and other ligament injuries such as the medial collateral ligament. 

Patients who have injured their anterior cruciate ligament tend to have a knee that gives way from time to time especially on sporting activity that involves turning and twisting.  In time they can damage their knee irretrievably.

Over the last 20 years there have been tremendous advances in the treatment of various conditions of the knee via keyhole surgery.  An ACL reconstruction is a very successful procedure if done well and a number of high level professional athletes return to their pre-injury sporting level after a careful reconstruction and good rehabilitation with physiotherapy

Mr Samuel Rajaratnam

Consultant Orthopaedic Surgeon

Mr Sam Rajaratnam FRCS (Tr&Orth) is a Consultant Orthopaedic Surgeon specialising in all aspects of knee surgery at The Horder Centre, in Crowborough and The McIndoe Centre, in East Grinstead.

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