Knee Joint Replacement
A knee joint replacement is a major operation, and it takes several months for the tissues about the knee to heal and remodel, and the body takes time to make a general recovery from surgery.
You can expect a feeling of tiredness in the weeks following surgery. This is due to the effect of the anaesthetic, a disturbance of metabolic functions, and the loss of blood which takes time to reform. A good healthy and balanced diet is important. You should lead a quiet, orderly lifestyle and follow a progressive daily exercise and walking programme. Try and avoid stress and becoming over tired. Riding an exercycle is excellent for regaining your fitness. Swimming, water walking and exercising in the pool are recommended – as soon as you feel confident enough getting in and out of the pool.
Crutches are used to assist you with getting back to normal walking as soon as possible. It is best to graduate from two crutches to walking fully independently as soon as possible. However, you may feel the need to use a single stick or crutch for confidence beyond that point.
The implanted knee parts are all quite solid immediately after your operation, and will quite safely take your weight.
From the outset, it is important to get the knee joint moving. Your hospital physiotherapist will assist you with this. Depending on your progress, you may need a physiotherapist to oversee your progress following discharge from hospital.
You will be discharged from hospital with a waterproof dressing on the knee. This can come off in 4-5 days. The stitches are absorbable and are under the skin.I will meet you for a follow up appointment 10-14 days following discharge from hospital.
A further post-operative visit will take place at the 6 week and 3 month post-operative point. An X-ray of the knee will be taken then, which serves as a reference for future X-rays to be compared to.
Following surgery, you can expect to make a continuing recovery for up to 4-6 months.
Should you have any concerns relating to your knee throughout this time, I am able to see you at my office, by appointment at any time. Should you experience any increase in pain from the knee, reddening, swelling or discharge from the wounds (suggestive of an infection), or any abnormal mechanical sensation from the knee (clicking, clunking or pain), could I ask you to let me know about it promptly.
The long-term concern with knee replacements is of wear of the plastic spacer component of the implant. The plastic wear particles set up loosening reactions in the bone surrounding the implants. I now advise patients whose implants are approaching 15 years to have a review undertaken by an orthopaedic surgeon with a view to a plastic spacer exchange procedure. Should this be done before loosening of the implants in the bone occurs, and before any damage to the metal bearing surfaces happens, it is likely that this will substantially extend the life span of the implant. However, once loosening occurs, a redo 'revision' operation is necessary, and if loosening can be detected before much surrounding bone is lost in the process, the revision procedure is easier and carries less risk.
Joe has used the Zimmer Knee joint replacement system over his 20 years in orthopaedic practice. The long term results of the current evolution of the implant ("NexGen") as reported by the New Zealand Joint Registry are equalled by only one other implant.