Partial or Total Knee Replacement
Knee osteoarthritis similar to other osteoarthritis regions causes significant pain and decreased mobility. Majority o patient s will describe significant pain which is usually the strongest during the night and keeps them awake. Pain on exercising is another strong component of pain which patients are complaining off. In my experience vast majority of patients would like to get read of predominantly night pain, but pain on activities as well. On top of the pain patients regularly complain about clicking, grinding, locking, giving way, limited activities, regular use of painkillers, ...
There are different stages of knee osteoarthritis and only end stages will require knee replacement of any sort. It is crucial not to perform any form of knee replacement until all other options are not exhausted.
Stages of the treatment prior to the knee replacement are:
- painkillers (anti-inflammatories if possible)
- regular exercises
- knee arthroscopy
- painkillers (anti-inflammatories if possible)
Not very often second arthroscopy will be beneficial hence not regularly advised.
Knee injections as well have very limited use and success as well.
In my opinion it is safely to proceed towards knee replacement in cases of:
- X-ray shows "bone-on-bone" osteoarthritis and patients has majority or all clinical symptoms of osteoarthritis and/or
- Knee arthroscopy revealed "bare bone(s)" and patient has majority or all clinical symptoms of osteoarthritis.
X-ray and/or knee arthroscopy can advise on the type of knee replacement patient will very likely benefit from. In cases of osteoarthritis localised to medial or lateral compartment only, it is advisable to proceed with partial knee replacement. Clinically it looks that changes in the patella-femoral joint are not defining the outcome of the surgery, particularly if patients do not have any symptoms from the area prior to the knee replacement surgery.
Literature and registers suggest that numbers of partial knee replacements are relatively low comparing to the total knee replacement numbers. And also revision rate is slightly higher for partial knee replacement. There are many possible explanations. One I really believe in is that revision of a partial knee replacement to a total knee replacement is relatively easy to perform, when revision of a total knee replacement to another total knee replacement is not easy at all. Therefore we can relatively safely say that clinicians will more often opt for revision in partial knee replacement patients than in total knee replacement patients.
Why don't just do a knee replacement even in an early stage?
Patients who received a knee replacement to early in the process of the disease are not as satisfied with the outcome as are patients who reached the end stage of the disease. Explanation lies in the reason that knee replacement (predominantly total knee replacement) does not offer the same functional performance as does "normal" knee. Therefore restrictions to the knee function are significant. If the knee prior to the surgery was really bad, patients will be happy with a new knee, if the knee was not really bud, patients won't be happy as anticipated. Comparing to the real life scenarios: if someone is driving a used car which need occasional trips to the local garage and than this car is taken from them and replaced by a new bicycle, I would suspect that person won't be terribly excited by the replacement. When in case when someone is using an old bicycle to get around and than the scooter is replaced by an used car, that person will be trilled by the replacement.
What is the difference between partial and total knee replacement?
The main difference between partial and total knee replacement is in my opinion in cruciate ligaments. For a partial knee replacement cruciate ligaments must be intact or functioning when for a total knee replacement there ligaments get quite often sacrificed. It is the fact that knee with the functioning cruciate ligaments will much easier restore normal moving pattern when a knee without ligaments (total knee replacement) will not. From the same fact we can also explain the reason for difference in movement - partial knee replacement has significantly bigger range of movement comparing tot the total knee replacement.
Why do people have night pain but not as much daytime pain?
During the daytime people get distracted by different activities and take painkillers more often. When during the night level of painkillers in the blood drops relatively quickly and because of no regular toping-up the pain will wake you up. To top up with additional painkillers takes time.
More about Unicompartmental Knee replacement you can get from Zimmer Biomet Website.
1. Liddle a D, Pandit H, Judge a, Murray DW. Patient-reported outcomes after total and unicompartmental knee arthroplasty: a study of 14 076 matched patients from the National Joint Registry for England and Wales. Bone Joint J. 2015;97-B(6):793-801. doi:10.1302/0301-620X.97B6.35155.
2. Pandit H, Hamilton TW, Jenkins C, Mellon SJ, Dodd CAF, Murray DW. The clinical outcome of minimally invasive Phase 3 Oxford unicompartmental knee arthroplasty: a 15-year follow-up of 1000 UKAs. Bone Joint J. 2015;97-B(11):1493-1500. doi:10.1302/0301-620X.97B11.35634.
Medial Unicondylar Knee replacement versus Total knee replacement