Now imagine the complex knee joint as this pulley system, with its multiple ligament anchors, meniscus shock-absorbers, and cartilage-lined hinge; the long muscles of the leg are the ropes that move the system. Osteoarthritis (OA) is the rust and grit; lack of exercise and stretching, as well as poor diet, constitute the minimal maintenance.
Our bodies have a tendency to heal themselves, but when our muscles stay too tight for too long, they create abnormal motion in every joint they’re attached to. Over time, these abnormalities increase wear and tear on the joint, including damage to the menisci or knee cartilage. The greater the wear and tear, the greater the tissue inflammation. Chronic inflammation leads to scar tissue formation, and calcification of this scar tissue in and around joints is what we call degenerative joint disease, OA, or bone spurs.
When specific injuries such as meniscus tears are added to the system, the degeneration speeds up, as shown by a recent study in Arthritis & Rheumatism. According to that study, meniscus damage will almost triple the chances of OA of the knee occurring in older adults. (However, other studies show that OA can lead to meniscus damage—a chicken-and-egg scenario.)
Most joint pain actually comes from the surrounding muscle tissue. When properly treated and regularly stretched (and stimulated through exercise), this muscle pain can be dramatically reduced and the motion of the knee can start to be retrained.
One of the most common reasons for abnormal muscle tension around the knee is excessive sitting. Sitting causes chronic tightness in the hamstrings, calves, and hip flexors, as well as weakness in other major muscle groups like the abdominals and gluteals. This leads to secondary tightness in the thigh muscles (quadriceps), the major mover of the knee. When both the hamstrings on the back and quadriceps on the front are tight, the knee joint has more pressure on it, creating additional wear. Factor in 20 years of desk-sitting and driving, which tighten and weaken the muscular movers of the knee, and it’s easy to see why so many people in their 40s and 50s have knee problems.
Solutions? Take a break from seated postures every 15 minutes; stretch your hamstrings and calves at least three times a day (more often if you’ve been diagnosed with knee OA); and try yoga for whole-body stretching and strengthening. If you’ve had undiagnosed knee pain for more than a month, get an evaluation from a qualified health professional.
Other factors to consider:
- Being overweight speeds up joint degeneration by increasing stress on all joints.
- Foot and ankle problems can lead to unstable joints at every level above, namely the knee. (Picture the body as a house of cards—what happens when you knock down the bottom card, the foot?)
- Chronic dehydration (from drinking too much caffeine and alcohol and too little water) can also affect the cartilage and menisci, which have a high water content.
Keep in mind that there’s no factory warranty for your knees: You have to provide the maintenance!
Thomas K. Hyland Robertson, DC