This is a recent picture of my young niece showing her inherited lax, hyper- extending knees. My dad and brother, (her father) have them, as do I and several other members of the family. My knees and elbows used to hyperextend a full 20 degrees and my anatomy professor would speculate on the shape of the end of my humerus. We chuckle about the classic familial stance but it is obvious that the lower leg and patella are well out of alignment with the femur.
There are several risk factors for osteoarthritis of the knee. I have seen a number of plumbers and construction workers, particularly those who use jack hammers, with severe, premature joint damage. Years of walking on poorly aligned joints, whether from joint laxity, flat feet, limb shortening or scoliosis also take a toll. Some people have a genetic predisposition to cartilage defects. Osteochondritis dissecans affects young joints as well as old. My surgeon has suggested I may have this condition. This summary of possible causes of osteoarthritis was copied from the website of the American Association of Orthopaedic Surgeons. I am adding it as web links have a tendency to go dead quickly.
Heredity. Some people have an inherited defect in one of the genes responsible for making cartilage. This causes defective cartilage, which leads to more rapid deterioration of joints. People born with joint abnormalities are more likely to develop osteoarthritis, and those born with an abnormality of the spine (such as scoliosis or curvature of the spine) are more likely to develop osteoarthritis of the spine.
Obesity. Obesity increases the risk for osteoarthritis of the knee and hip. Maintaining ideal weight or losing excess weight may help prevent osteoarthritis of the knee and hip or decrease the rate of progression once osteoarthritis is established.
Injury. Injuries contribute to the development of osteoarthritis. For example, athletes who have knee-related injuries may be at higher risk of developing osteoarthritis of the knee. In addition, people who have had a severe back injury may be predisposed to develop osteoarthritis of the spine. People who have had a broken bone near a joint are prone to develop osteoarthritis in that joint.
Joint Overuse. Overuse of certain joints increases the risk of developing osteoarthritis. For example, people in jobs requiring repeated bending of the knee are at increased risk for developing osteoarthritis of the knee.
Many people have at least one of these risk factors and recognizing them is the first step in taking possible preventive or corrective action. I am seeing Lynn, an excellent physiotherapist who is supervising my rehab program. It is impossible to be truly objective with yourself and it is also hard to push through pain without encouragement. She noted that I was rolling outwards on my feet with each step as I compensated for muscle weakness around the knee. My Xrays show more lateral than medial narrowing of the joint space of my knee.
I took a look at my winter hiking boots which I have worn for several seasons now. The lateral wear on this right boot is very noticeable but I had not paid any attention to it. While I had little pain until recently, I was losing movement and strength in the knee for some time. Our bodies are adept at finding ways to compensate for imbalances. Many people, especially women, have a tendency to flat feet and valgus or "knock knees". Their heels tend to wear opposite to mine and they sustain damage to the medial compartment of their knee. This is so common that knee hemiarthroplasties (Oxford replacements) are being done to replace only the medial half the knee joint.
Last week I purchased a new pair of Keen shoes for winter. Beth from Maine* had recommended their sandals and I bought a pair in June, wearing them every day until the snow came. When I switched to other shoes, my knees became more painful. The Becka calls my new Keens "Frankenstein shoes" and tells me I could go Goth with them, but they feel heavenly on my feet. Women and shoes are often in conflict. I have purchased shoes that hurt because they were attractive and on sale. High heels displace weight to the front of the knee joint and this can contribute to painful patello-femoral arthritis over time. The Keens have a generous toe box. Most women squeeze their feet into narrow toed shoes and are four times more likely than men to develop foot deformities. Walking with bare feet causes the least strain on the knee joint as the many small joints in the foot absorb the forces of weight bearing well. (reference) Bare feet are not an option for most of us so we cram our feet into rigid, often ill-fitting shoes and walk on hard surfaces for much of the day.
I continue to walk on the track with my poles and completed 2-1/2 km yesterday. I am not pushing for distance but am paying attention to how I am walking as I try to correct my gait pattern. I will get an orthotic assessment as part of my action plan to protect my knees. In my next instalment I will review the exercises which have been most helpful for me.
*Here and here are links to Beth's posts about Keen Shoes. I am not endorsing them exclusively as there are other shoes available that provide excellent support. But these are the most comfortable shoes I have worn.
Getting Back on Track: Part One