The sliding surfaces of each joint are covered with hyaline cartilage.
This type of cartilage is characterized by high compressive strength but low tensile strength.
The cause of damage to the cartilage layer can be diverse. Accidents, overuse, improper loading of certain cartilage areas with angular deformity of the upper and/or lower leg (see section: axis correction), misalignment of the kneecap (see section: kneecap), rheumatic and inflammatory diseases and other factors
Cartilage defects of the knee joint pain can lead to strong interchangeable pain, "Bamstigkeitsgefühl” (pretentious feeling) in the knee by a joint effusion (= irritation) and significantly lowered performance.
The normal, smooth and solid hyaline cartilage thigh and cartilage damage in stage I and II are shown.
For the nature and severity of the complaints, location, size and extent of the depth of the damage are responsible.
The symptoms often do not correlate with the extent of the damage. They are highly individual and hardly obey any laws.
There are four stages of cartilage damage, whereof the stages III and IV already represent the transition to osteoarthritis. The names originate from the U.S. and are figurative:
I - Blister (blistering, softening)
II - Teddy Bear
III - Crab meat
IV - Moon
Hyaline cartilage (chondromalacia) stage II, frayed degeneration without significant loss of cartilage thickness
Stage III chondromalacia, deep creases, detached cartilage areas, decreasing cartilage thickness and abraded areas paint a colorful picture of the increasing joint destruction
Stage IV chondromalacia. Cartilage no longer exists. Joint destruction and bone abrasion. Joint deformation and transition to severe osteoarthritis.
Arthroscopic treatment is to stop the ongoing joint stimulation by the abrasive material of the rough cartilage surface, to halt the progression of cartilage breakdown as far as possible and to also set the reparation activity going. Usually the stage 1 requires no treatment, in stage II and III a motorized drawing knife is used to smoothen the cartilage surfaces, undermined edges and dead cartilage are removed (stage IV, see section osteoarthritis).
A badly bruised right knee: On the inside you can see dead cartilage parts (stage III). Below exposed, dead bone without cartilage lining (stage IV), additional exterior meniscus lobe tear.
Through the production of smooth cartilage surface abrasion is reduced, and chronic irritation subside.
With the high-frequency device, it is possible to create smooth, "sealed" cartilage surfaces.
Immediately the postoperative period begins treatment with ice packs, decongestant medications and possibly a motorized passive splint (CPM). In the first phase of the treatment just after cartilage surgery the movement (massages and better nutrition of the non-perfused cartilage) and low load is of great importance. The leg can be used after the surgery (walking). Preventive care for three to six weeks.
Ability to work
Depending on the patient's age, degree and extent of the cartilage damage, patients with sedentary work may work after about two weeks, those with physical activity take about five to six weeks before returning to work.
Due to the diversity of cartilage damage, this point must especially be discussed individually with regard to age, body weight, muscle performance and sport.
Good results are obtained after a cartilage smoothing in about 90 percent of stage II cases, and nevertheless in 75 percent of stage III cases.
The complications are comparable with those after an arthroscopic meniscus treatment, only the rate of thrombosis increases to about 3 percent due to the longer discharge.