The knee is a joint governed by many ligaments (in fact, only flexion-extension is allowed) and endowed with rich proprioceptive innervation; this causes postoperative mobilization of the prosthesis to be characterized more frequently by pain, a condition that occurs more frequently than for the hip, as in hip replacement or hip arthroscopy.
This pain, present in the first few days after surgery, should not be frightening; in fact, it gradually disappears, giving way to proper functional recovery of the knee.
If, on the other hand, postoperative knee replacement pain persists over time, changes its characteristics, and cannot be controlled through pain medication, it is possible that the replacement may have a problem.
It is advisable to see your orthopedic surgeon immediately if:
- pain persists beyond six weeks;
- intense burning is felt;
- sudden twinges and/or sags occur.
Painful knee replacement or infected knee replacement?
The first thing to rule out when the function of a knee replacement gets worse instead of better is the presence of an infection.
Periprosthetic infection is certainly the most fearsome of the complications, as well as the one that may require the longest course for recovery.
By performing blood physical examinations and possibly ultrasound sampling from the joint, this rare but extremely dangerous complication can be ruled out.
It is very important to recognize a prosthetic infection early because, in this way, it can be treated without the prosthesis having to be removed. If, on the other hand, the elapsed time was already too long (more than 30 days), a surgical cleaning coupled with antibiotics will fail to eradicate it, and it will be necessary to remove the prosthesis and then implant it again after healing.
Identify the cause of painful knee replacement
Excluding the possibility of an ongoing infection, it is possible that, in the first few weeks, the pain felt during walking may be due to not fully functional recovery.
It will, therefore, be necessary to insist on rehabilitation, looking, in parallel, for the mechanical causes of pain.
The first thing will be to perform a thorough clinical and medical history examination: knowing where and when the pain appears is of primary importance in reaching a diagnosis.
Subsequently, the progression of radiographic images and, possibly, a CT scan (with metal artifact exclusion protocol), are of great help in highlighting the cause of prosthesis malfunction.
Knee replacement: therapies in case of pain
Before considering surgical revision, it is essential to rely on renewed physical therapy as well as antalgic (pain reduction) therapy : placement of a perinervous catheter or use of antalgic radiofrequency allows pain-free functional recovery.
Knee replacement recovery is achieved by a multidisciplinary team: not only the work of the orthopedic surgeon is important, but also that of the physiatrist, physical therapist, and sometimes the pain therapist.
The surgical revision
If a definite cause has been identified that can explain the persistent knee replacement pain and, despite repeated physical and antalgic therapies, good function of the joint has not been achieved, then it will be necessary to plan a surgical revision, performing a knee replacement reimplantation.
Do you have a painful knee replacement problem? Please feel free to contact me.
