ANTERIOR KNEE PAIN Information Leaflet Your Health. Our Priority.
Page 2 of 5 What is anterior knee pain? Anterior knee pain simply describes the symptoms of pain at the front of the knee, no matter what the cause. It is a very common condition. What are the symptoms of anterior knee pain? The symptoms are of pain at the front of the knee or behind the kneecap. The pain can be worse on going up and especially down stairs, also with prolonged sitting or driving and when kneeling or squatting. All of these can be made worse when trying to lift heavy items at the same time. The knee can giving way and sometimes gets stuck, which you have to leave for a while before it can move again. You can also get puffiness at the front of the knee. The knee commonly has a feeling of clicking and crunching. Where does the pain come from? The pain usually arises from the patello-femoral joint. This is the joint between the front of the lower thigh bone and the kneecap (patella), where it sits in a groove. The kneecap acts like a pulley allowing the thigh (quadriceps) muscles to pull the knee straight. To function normally it must sit centrally as it tracks through its groove during knee movements. What are the common causes of anterior knee pain? Muscle imbalance: Sometimes the control or balance of the thigh muscles can affect the tracking of the kneecap in its groove. Chondro-malacia patellae: This term describes changes within the lining of the patello-femoral joint. The surfaces are made of cartilage and can become soft and split. This can cause pain in its own right or may be the result of the other causes listed here. Mal-alignment of the leg: The structure and alignment of your feet, knees and lower limbs may affect the tracking of the kneecap within the groove. Trauma: A direct blow to the front of the knee can cause irritation to the back of the kneecap and sometimes swelling within the joint, which can lead to reduced control of the thigh muscles. The pain may arise from the injury to the lining of the kneecap, as well as from tracking problems created by the muscle weakness. Osteoarthritis of the patello-femoral joint: The patello-femoral joint may become worn. As the joint surface is worn away it becomes painful. The majority of anterior knee pain is caused by several rather than just one of these factors Will I need any special tests? You will have your knee problems diagnosed by having your symptoms assessed and an examination of your knee. Sometimes an X-ray is performed. Further assessment is based on your response to your treatment (see below). Rarely a CT or MR scan is organised, which can
Page 3 of 5 help plan surgery (if contemplated) or assess for other knee problems if they are suspected. Your surgeon will let you know whether any special tests will be needed. What is the treatment? Treatment usually consists of maintaining an ideal body weight and physiotherapy including home exercises. Sometimes podiatry can help and surgery is rarely needed. You will be assessed as to the treatment plan that will suit you best. Why do I need to watch my weight? The patello-femoral joint takes a considerable load through it during certain activities. This is because it is very small and works hardest when the knee is bent. As an example: if you are 2 stone over weight your kneecap will take an extra 14 stone through it when getting up from a crouched position. If you wish to see the effect of being over-weight try carrying a heavy bag of shopping up and down stairs, your symptoms will probably be worse doing this. If you keep your weight to the level it should be for your height (body mass index) you can lessen your symptoms. What does physiotherapy consist of? Specific exercises to re-train the muscles controlling the kneecap. Stabilising and stretching exercises for any other muscles in the trunk, hip and leg that may affect your kneecap alignment. Strapping to improve the tracking of the kneecap. Mobilisation and stretching of soft tissues. Electrical stimulation to help with muscle control. Even if you are very active it is very important that you learn the specific exercises. Otherwise your body will continue to do the wrong thing. This results in the strong muscles getting stronger and the weak getting weaker. Once the physiotherapy course is completed it is very important that you continue the exercises at home, which will prevent your symptoms returning. What can podiatry offer? The Orthopaedic team or your physiotherapist may feel that your foot biomechanics are contributing to your knee pain and they may refer you to the Podiatry Department. An assessment will be made of your foot position and alignment in relation to your pain. If it is deemed necessary an orthotic (insole) will be made for you to help improve your alignment. Can an operation help me? It is very rare that patients with anterior knee pain can be helped with surgery. This is because surgical procedures for these problems have a limited success rate and can lead to further problems. Any operation on your knee will weaken the muscles and can worsen the pain.
Page 4 of 5 Despite this an operation can sometimes help people with anterior knee pain. They are usually performed when it can be clearly identified that the kneecap is tracking off centre for a definite reason. The operations that are usually performed are: Lateral release: The tight structures on the outside of the kneecap are cut to improve its position and tracking. This is usually performed at the same time as an arthroscopy. Patellar re-alignment: A more extensive operation to improve the tracking of the kneecap. It involves moving the tibial tuberosity, where the patella tendon (tendon attached to the kneecap) attaches to the tibia (shinbone). Soft tissue releases are often performed at the same time. Replacement: When the patello-femoral joint is very worn then the only solution sometimes is a replacement. Depending on the state of the remainder of the joint this may involve the patellofemoral joint alone or the whole knee joint. Will I definitely get better? Most patients (95%) improve with monitoring their weight and exercises guided by physiotherapy. However, most patients with anterior knee pain notice their symptoms do fluctuate with time. This is often because they have forgotten to continue their exercises after completing physiotherapy. For those requiring surgery the results are usually good, when the right operation is chosen for the right reasons. If you still have any questions please ask your surgeon or physiotherapist. Contact us Sarah Thompson 0161 419 4037
Page 5 of 5 If you would like this leaflet in a different format, for example, in large print, or on audiotape, or for people with learning disabilities, please contact: Patient and Customer Services, Poplar Suite, Stepping Hill Hospital. Tel: 0161 419 5678. Email: PCS@stockport.nhs.uk. Our smoke free policy Smoking is not allowed anywhere on our sites. Please read our leaflet 'Policy on Smoke Free NHS Premises' to find out more. Leaflet number TO08 Publication date January 2016 Review date January 2017 Department Trauma and Orthopaedics Location Stepping Hill Hospital