According to the American Academy of Orthopaedic Surgeons, running places a significant amount of stress on the knees, and runners may experience numerous conditions that cause pain around the knee, such as anterior knee pain syndrome, patellofemoral malalignment and chondromalacia patella. MayoClinic.com states that runners may develop tendon injuries and iliotibial band syndrome, and that some teenage runners may experience pain associated with Osgood-Schlatter disease. Knee problems associated with running can be minimized by wearing appropriate footwear and training wisely.
Inappropriate Footwear
According to a 2006 study published in "Arthritis and Rheumatism" by Dr. Najia Shakoor, wearing shoes may increase loads on the lower extremity joints, including the knees. Shakoor states that wearing conventional shoes increases the prevalence and progression of knee osteoarthritis, also known as degenerative joint disease. Dr. Ray McClanahan, a sports podiatrist based in Portland, Oregon, notes that running shoes have four design characteristics that predispose runners to lower extremity injury and pain: heel elevation, toe spring, tapering toe boxes and rigid, inflexible soles. McClanahan believes that allowing the foot to function as if it were barefoot inside the shoe is an important aspect of knee and lower extremity injury prevention and rehabilitation. Using running shoes that are flat, wide in the toe box and flexible may reduce the likelihood of experiencing running-related knee problems.
Leg Length Inequalities
According to a 2002 article by podiatrists Mark A. Caselli and Edward C. Rzonca in "Podiatry Today," there are two types of leg length inequalities (LLIs) or discrepancies: structural and functional. Structural or anatomical LLIs are caused by the shortening of one or more lower extremity bones, or by spinal abnormalities such as scoliosis. Functional LLIs result from muscular weakness or imbalance throughout the lower extremities. Caselli and Rzonca note that LLIs are the third most common cause of running-related injuries, occurring in 60 to 90 percent of runners. Lower extremity symptoms associated with LLIs include the following knee and foot conditions: arthritis, patellar tendonitis, patellofemoral pain syndrome, iliotibial band syndrome with lateral knee pain, medial tibial stress syndrome or shin splints, plantar fasciitis and metatarsalgia. Having leg length evaluated for discrepancies, along with receiving appropriate treatment, can be a helpful way to prevent or reduce running-related knee pain.
Running Terrain and Training Errors
The type of terrain runners traverse may be a cause of running-related knee pain. Caselli and Rzonca note that environmental factors--such as roadway drainage crowns and banked running surfaces, in conjunction with excessive shoe wear--can create a scenario that mimics a leg length discrepancy. Depending on how a person runs on a banked surface, she may either accentuate or correct her structural or functional LLIs.
According to the Nicholas Institute of Sports Medicine and Athletic Trauma (NISMAT), the type of training surface runners train on also may create or exacerbate running-related injuries. Soft or hard surfaces and hills can affect the mechanics of running and predispose a runner to knee and other lower extremity injuries, especially if the training progression is not gradual. A gradual progression in training intensity and duration, along with a gradual increase in the number of hill workouts per week, allows the body sufficient time to adapt to the increased demands placed upon it, and will minimize knee injuries associated with running.
References
- American Academy of Orthopaedic Surgeons: Runner's Knee (Patellofemoral Pain)
- Mayo Clinic: Knee Pain
- "Arthritis and Rheumatism"; Walking Barefoot Decreases Loading on the Lower Extremity Joints; Najia Shakoor, et al.; September 2006
- Northwest Foot & Ankle: Caring for Your Feet
- "Podiatry Today"; Detecting And Treating Leg Length Discrepancies; Mark A. Caselli, D.P.M., and Edward C. Rzonca, D.P.M.; Dec. 1, 2002
