The knee is a finely tuned joint and is sensitive to the overall alignment of the limb. People with valgus alignment or ‘knock knees’ tend to put a disproportionate amount of load on the outside of the joint. People who are varus or ‘bow legged’ will increase the load on the inside of the knee. This leads to early wear and arthritis of the affected area.
Osteotomy means to cut the bone. Simply put, a fracture is created and the alignment is changed to offload the damaged part of the knee. Where the fracture is made and how much correction is required depend on individual factors. Typically the osteotomy is held with a plate and screws. Because the bone is broken in the process, a period of restricted weight bearing is typically required after surgery.
Unicompartmental knee replacement (UKR)
The knee is typically divided into three ‘compartments.’ These are the lateral, medial and patellofemoral. Often osteoarthritis will only affect one of the compartments of the knee and only that compartment requires surgical replacement. This is referred to as ‘unicompartmental replacement’ or having a ‘half knee’ done.
The advantages of a uni knee relate to less surgical trauma. Hospital stay is less, pain is less, range of motion is better. Importantly, because you retain your ligaments and capsule, the knee feels more natural compared to having a total knee replacement.
For a UKR to be suitable, there are very specific requirements. Your knee must be stable, with a good range of movement and your pain should ideally be localised to one place. UKR is an unforgiving procedure and requires careful attention. Dr Young’s preference is to use custom made cutting guides based on a pre operative MRI to ensure the size, position and alignment are correct. This is essential to ensure a functional, long lasting result.
Total Knee replacement
Total knee replacement is the most durable and effective long term treatment for knee arthritis no longer responding to non surgical treatment. It involves the removal of the damaged bone and cartilage, replacing it with metal and plastic components. The bone cuts allow the surgeon to correct deformities and restore motion as well as taking away pain.
Knee replacement is major surgery and requires careful counselling beforehand. Often non-surgical treatments will be appropriate initially. These can be discussed at your consultation.
Successful surgery requires careful attention from both your surgeon and yourself. Attention to post operative exercises is essential to lead to a happy result.
Revision knee replacement
Modern knee replacements have excellent results and 90 plus percent will last 15 years or more. Unfortunately some still do wear out and require revision. Other causes of revision are infections, fractures and (rarely) mal-position leading to stiffness or pain.
Revision surgery is complex and requires a careful and measured approach. It often requires extensive investigations and carries higher risks than primary surgery. Dr Young has a particular interest in revision surgery and can counsel you through the process.