Mr Michael Moss

Consultant Orthopaedic Surgeon

01243 753032

Although a well positioned knee joint will last many years, knee joints, like any mechanical structure, will eventually suffer wear and become more unstable and possibly uncomfortable. Patients will notice that the knee joint is not functioning as well and they may experience more discomfort on performing normal activities such as walking, sitting and climbing stairs. The joint may become puffy or swollen and sore.

Over the last 20 years, I have established a recognised referral practice at both St Richard’s Hospital and at my private practice at the Nuffield Health Chichester Hospital. The knee and hip revision services at St Richard’s Hospital have subsequently grown over the years as consultants from the surrounding area of Sussex, Surrey and Hampshire have referred cases for expert evaluation and remedial or revision surgery to remove and replace unsatisfactory prostheses. It is now one of the busiest revision units in the country.

The failure of a knee joint through wear is a gradual process and current implants would normally be expected to last between 15-20 years, depending on the age and activity of the patient. However, the resurfacing or replacement of a knee joint is a demanding, technical procedure for the surgeon and there are a small group of patients for whom knee surgery itself has not been immediately successful. It is recognised that, occasionally, technical errors in implanting a complex knee prosthesis may result in a sub-optimal or disappointing clinical result for the patient. Occasionally, patients may feel they have not gained enough movement in the knee, the knee joint remains more painful or, indeed, is not as functional as the patient would wish. If the implantation of a knee joint or the performance of the knee joint after surgery has been less than satisfactory, or sub-optimal, occasionally it may be necessary to remove the implant and re-perform the surgery.

Revision surgery is a more significant undertaking for patients and recovery is therefore often longer than what one might expect for standard primary ‘first time’ knee replacement surgery. However, often results can be very encouraging, particularly if the primary knee joint replacement surgery was less than satisfactory in the first instance. The procedure is often a fairly lengthy operation with removal of the unsatisfactory implant from the knee and the building of a modular or custom built knee prosthesis in theatre around the patient’s own specific requirements for movement and stability. This requires the use of a specialised prosthetic system to re-align the knee and correct any technical issues that may have been present in the first surgery or, indeed, to address the wear that has occurred in any knee joint that has failed through natural usage.

The recognition of technical failure within the replaced knee is a complex and challenging role and relies on a high degree of expertise and experience. I am an acknowledged expert in the field of revision knee surgery. I lecture internationally to other orthopaedic surgeons and have published research on the complexities and difficulties involved in this type of surgery.

Frequently Asked Questions

What is Osteoarthritis?

Osteoarthritis is the most common form of arthritis. It is a degenerative joint disease that causes deterioration of cartilage between bones. It can be caused by aging, genetics, obesity, and joint injuries from sports, work, or accidents.

In 2012, 92% of hip joints replaced in the UK were needed because of osteoarthritis.

In the same year, 98% of the knee joints replaced in the UK were because the patient was diagnosed with osteoarthritis.