Osteoarthritis (OA) is a degenerative disease of a joint that leads to progressive loss of the articular cartilage. This leads to pain, joint deformity, ligamentous laxity and eventually decreasing function. The incidence of OA in the knee is 240 per 100 000 people per year. The cause of OA is multifactorial with the main risk factors being over-weight, previous trauma, females and genetics.
In the general, the articular cartilage starts to retain water within its structure, leading to a decreased strength and an increased wear. Eventually the cartilage is completely worn away, exposing the bone and putting an increased stress on the bone. This can occur in all the compartments of the knee (the knee has 3 different compartments; the patellofemoral, medial and lateral compartments) or can affect any of the compartments alone or in combination.
1) Lifestyle modification – your lifestyle must suit your knee
a) Best activity is the least weight bearing such as swimming and cycling
b) Weight loss is very important
c) Rehabilitation to keep the muscles around the knee strong
i) Analgesia/pain killers (such as paracetamol or codeine)
ii) Anti-inflammatories (to decrease the swelling and inflammation)
i) Steroids (cortisone) – powerful anti-inflammatory effect and good if the knee is swollen
ii) PRP (platelet rich plasma) injections – see info on PRP on website but have a good result in “dry” or non swollen
knees for pain relief. Not clinical proven but are biological.
3) Altering weight distribution through the knee
a) Insoles in the shoes
b) Braces – unloader braces can help to relieve the pain in the worn compartment
c) Walking stick
a) Arthroscopy – good if minimal wear and mostly mechanical symptoms but can make the symptoms worse. Needs to be
strictly individualised to each patient
b) Osteotomy – Best in patients under 60-65yrs with OA of one compartment. A cut is made in the tibia to realign it and move the weight bearing axis into the preserved or unaffected compartment. Patients can return to all sports with no restriction post recovery. This procedure does not preclude any future procedures, as needed.
c) Uni-compartmental or partial knee replacement – older patients who are less active with disease limited to one
compartment only. Only the diseased compartment is replaced and the ligamentous structures are preserved.
d) Total knee replacement – this is done when more than one compartment is diseased and the whole joint is then
replaced. The main indication for this procedure is pain and this is decided by the patient as to when they feel that they
cannot cope with their activities of daily living.