Chondromalacia patella is a degeneration of the articular cartilage that covers the patella, in the inner area where the femur articulates. It represents between 10% and 25% of consultations for knee problems to specialists in Traumatology and Physiotherapy, and affects young adults, somewhat more women.
When the hyaline cartilage, whose function is to facilitate the sliding of the bones at their articular ends and the absorption of impacts, is damaged, the patella and the femur do not slide smoothly between them, fact that increases the wear and the friction between them.
Although it can impose limitations on us, chondromalacia patellae is not the end of an athlete, nor of a runner, nor even of a marathon runner.
There are four degrees of injury:
- Grade 1: edema and softened cartilage.
- Grade 2: cracking or alteration of the cartilage surface.
- Grade 3: alteration of the deepest layers of the cartilage.
- Grade 4: involvement of the subchondral bone.
Causes of chondromalacia patellae
Although the causes of many chondromalacia are unknown (idiopathic), most are thought to be caused by repeated low-intensity trauma. On the other hand, there are many predisposing factors that favor the appearance of this pathology, such as alterations in knee alignment, repeated medium or high intensity trauma, dysplasias of the joint that cause poor congruence between the patella and femur, high intensity direct trauma or, less common, rheumatic or autoimmune diseases, such as rheumatoid arthritis, obesity and metabolic diseases, infections or sequelae of accidents.
Diagnosis of chondromalacia patellae
The diagnosis of chondromalacia patella is made by clinical history and imaging tests.
Typically, patients present with pain in the anterior aspect of the knee, sometimes radiating to the popliteal fossa, crepitus on bending and extending the knee, burning, a feeling of pressure or swelling or, less commonly, episodes of failure or insecurity, especially when descending and ascending stairs or after prolonged sitting with legs cramped, when starting to walk (“movie sign”).
To confirm the diagnosis, or to rule out other causes of pain, magnetic resonance imaging is performed. The simple radiographs and the CAT scan or dynamic scan reflect that there are bad alignments of the patella with the femur, bad position or bad congruence (they are forms, more or less serious of dysplasia). All this contributes to the fact that the support between the two bones is not optimal, facilitating the precocious wear (it is like a car with the wrong parallel, the wheels wear more).
Treatment of the chondromalacia patellae
There is no definitive treatment that reverses the degeneration of the cartilage. Depending on the degree and the limitation of the patient, it is possible to resort from the physiotherapy or the exercise, to the use of protective drugs of the cartilage, the infiltrations of ortokine, growth factors or hyaluronic acid.
With the postural cares it is wanted to avoid to be with the knee flexed during long time followed. It is necessary to bend and stretch it frequently, and to avoid kneeling or squatting. In addition, it is better not to go up and down stairs if it is not necessary or if we have chondromalacia, they do not train the knee and wear out the cartilage.
In case of chondromalacia patella physiotherapy is aimed at relieving pain and strengthening the quadriceps. Undoubtedly, the runner may have to modify his stride and give up some exercises, but this is better than not running at all. Adapting the exercise or modulating it or combining it with other disciplines that are less traumatic to the joints can be key.
Chondroprotective drugs have the strongest scientific evidence for long-term cartilage preservation. Other products such as collagen, magnesium, hyaluronic acid… may be good, but do not have the evidence required by the scientific method.
Infiltrations of hyaluronic acid and plasma rich in growth factors improve the sensation of stiffness, crepitation, pain and mobility of patients. However, in the treatment of degenerative joint injuries, plasma rich in growth factors has shown to be more inconsistent, with little lasting improvement.
Orthokine (autologous conditioned serum) is a biological therapy through which blood obtained from the patient is incubated for 7-8 hours at body temperature (37º) in special syringes containing glass beads. In this way, growth factors are generated as well as large quantities of the IL-1ra protein, which is the main natural anti-inflammatory of our organism. This combination is especially indicated in chondromalacia, painful arthrosis and inflammation, both in joints and back, and tendinopathies. Many studies highlight their benefits in pain reduction, improved mobility and, above all, their results are longer lasting than with other therapies, with improvements that can last more than two years.
On the other hand, true stem cells have little scientific evidence, in small series. The results are similar to other infiltrations but their price can be between 3-10 times higher than the aforementioned therapies, depending on whether they are cultured or not, so they cannot currently be considered a common treatment option.
Arthroscopies do not have to be performed to establish the diagnosis of chondromalacia. Cleaning arthroscopies” usually offer a transitory improvement, probably because very unstable cartilage bangs are regularized and inflammatory mediators are cleaned, but after a while, after weeks or months, the patient is the same. These improvements can usually be achieved with infiltrations, without the need for surgery.
In focal cartilage defects, they can be used to make cruentations or bleeding, as well as microperforations in the subchondral bone that stimulate the slow repair of the damaged cartilage, although it is difficult for this to reach optimum quality.
Chondrocyte culture, together with growth factors or other substances, is used for focal cartilage defects. This occurs when there is a “crater” in the cartilage. They are applied in defects of 2-8 cm square, but chondromalacia is, in general, a diffuse defect of the entire cartilage, not a focal osteochondral lesion (one that affects the cartilage and the subchondral bone), so this treatment would not be indicated. These cell culture techniques involve two operations (one to harvest cartilage and one to implant it). Its price is very high and, after 25 years in use, despite good clinical results, it has very restricted indications and limitations.
Living with chondromalacia patellae
Chondromalacia hurts seasonally, sometimes more, sometimes less, depending on many factors. It is possible that the athlete may have to modify his way of training, perhaps combine other sports, but it does not mean that he has to give up his favorite sport.
There is no scientific evidence to quantify what is more important in the development of osteoarthritis: running, even if it is less, taking chondroprotectors, occasionally infiltrating the knees or living, without running, weighing 10-15 kilos more day by day and assuming the effects of the metabolism of adipose tissue, which generates many inflammatory radicals that damage the connective tissue, in addition to the mechanical factor.
As a traumatologist, I always explain all these aspects to patients, the modulating role of exercise on the pain threshold or the protection of the musculature on the joint. Doing sport, running, so fashionable, demands a sacrifice but allows us to live our life at a different speed. If we were once, as some anthropologists explain, hunters by exhaustion of our prey, and in view of the fever for sport that surrounds us, there is no doubt that we were “born to run”.