At Spire Clare Park Hospital in Farnham, Surrey, we have several orthopaedic surgeons who carry out unicompartmental knee replacements routinely. They work within our laminar flow theatres to reduce the risk of infection. With the support of our physiotherapists, you will be up and about and ready to go home within a matter of days.
Ask your GP for a referral to the orthopaedic team Spire Clare Park Hospital. Alternatively, contact the customer services team for more information.
About unicompartmental knee replacement
In some types of arthritis of the knee, only the medial (inside) part of the joint is affected. In this situation it is possible to replace the damaged part of the knee without resorting to a total knee replacement.
Initially, arthritis can be treated with painkillers, anti-inflammatories, physiotherapy and, in the earlier stages, arthroscopy (keyhole surgery) but as the knee progressively wears the only long-term treatment is to replace the damaged part of the joint.
The surgery involves removing a very small thickness of damaged bone from the inside part of the knee. Much less bone is removed than in a total knee replacement and only from one side of the knee. The unicompartmental knee replacement fits inside this prepared space and is fixed to the bone with cement.
The operation takes about an hour and involves an 8cm incision on the medial (inner) side of the kneecap. This small incision does not involve cutting any muscle or tendons (as with a total knee replacement), thus enabling quicker recovery from surgery.
The UKR comes in three parts. The femoral component is made of metal, is curved and highly polished. The tibial component is made of the same metal and has a flat upper surface. A plastic component, which is curved on the top and flat on the underside, sits on the flat tibial surface and can slide backwards and forwards. This mimics the meniscal cartilage in the normal knee. The upper part of this plastic insert articulates with the femoral component. This type of knee replacement is called a meniscal bearing and has the advantage of sharing the load through the knee over a large surface area, which helps to reduce wear and hence make the knee replacement last longer.
After a unicompartmental knee replacement
The day after the operation your exercise regime begins. With the aid of a physiotherapist you will get out of bed and begin to exercise your new knee replacement. With perseverance, you should be able to climb stairs by day 2 or 3 and go home the following day.
You will need to continue attending physiotherapy as an outpatient. For most people it will take around 4 weeks to be walking reasonably. After three months you should be able to walk well without pain, climb stairs (leading with your operated leg) and be capable of a range of movement with your new knee from 0 degrees to at least 120 degrees.