Diagnostic tests for chondromalacia are eventually necessary, but initially chondromalacia is usually a clinical diagnosis where the physician examines the patient. Occasionally, there might be reasons to do an MRI scan because the knee pain is so pronounced that the physician suspects a meniscus tear.
However, to the surprise of everybody the MRI scan that may have been ordered, shows knee chondromalacia, chondromalacia of the patella and possibly also chondromalacia of the adjacent femoral bone (the inside articulating part of the lower thigh bone) instead. In this case where the meniscus was normal an arthroscopy is not necessary.
On the other hand, the patient may have been booked already for an arthroscopy without the benefit of a prior MRI scan. The surgeon may be surprised to find only chondromalacia, but no meniscal tear.
Management of grade III or IV chondromalacia
If there is grade III or IV chondromalacia, the surgeon may have to shave off any irregularities on the joint surface (thanks to www.beliefnet.com for this image) though the literature regarding this is not convincing that this is effective on the long-term. However, it may give the patient some symptom relief from the knee pain for a year or two. Ultimately this joint disease turns into knee osteoarthritis and a total knee replacement would have to be considered a few years further down.
X-rays are of no use as the hyaline cartilage does not show up on X rays except for grade IV chondromalacia indirectly as a slight joint narrowing. However, at that time there is palpable crepitation (=grinding) in the joint on physical examination.
Summary re. diagnostic tests for chondromalacia of the knee
1. history of joint pains and confirming crepitation (grinding) by physical examination.
2. MRI scan or CT scan prior to arthroscopy.
3. Arthroscopy when a tear of the meniscus is confirmed or when chondromalacia grade iV is found on MRI.
4. With end stage chondromalacia a few more years of functioning can be gained by arthroscopy with shaving of joint irregularities prior to a knee replacement at a future date.
References
1. The Merck Manual, 7th edition, by M. H. Beers et al., Whitehouse Station, N.J., 1999. Chapter 62.
2. EL Cain et al. Clin Sports Med 2001 Apr;20(2):321-342.
3. B. Sears: “Zone perfect meals in minutes”. Regan Books, Harper Collins, 1997.
3. Goldman: Cecil Textbook of Medicine, 21st ed.(©2000)W.B.Saunders
4. Ferri: Ferri’s Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc.
5. Rakel: Conn’s Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier
