Leg pain when walking is common patient compliant. Evaluating patients for a cause is often a complex process. Successful diagnosis hinges on performing a thorough history and physical examination followed by proper diagnostic testing and appropriate management. At a high level there are 3 groups of systems to be considered:
- Vascular (arteries and veins)
- Musculoskeletal (bones, joints, tendons and muscles)
- Neurological (nerves)
For a more comprehensive list of see http://dx.doi.org/10.1016/j.asmart.2015.03.003.
For the sake of this brief review, this discussion is focused on older patients, typically over 50 years of age that have leg pain when walking short distances. In general, it is fairly straight forward to identify pain that is related to bones, joints and tendons as the pain is usual easy to localize and patients are able to demonstrate where the pain occurs. Other types of leg pain when walking can be more difficult to correctly diagnose. Additionally, as people age, they may have more than one problem causing symptoms.
Patients with leg pain with exercise that is related to peripheral arterial disease (PAD) have a diagnosis called intermittent claudication (IC). The classic scenario is a patient who has no pain when standing, develops pain in the calf and/or thigh with walking, the pain worsens when hurrying or going up hills/stairs, and is relieved after 5-10 minutes of rest. The symptoms occur because the muscles of the leg are not getting enough blood flow.
Often patients do not have these classic symptoms because as people age they can have multiple problems contributing to their pain. One common source of confusion is the overlap of symptoms between patients with spine and nerve problems. Patients that have compression of the nerves in the spine develop symptoms similar to patients with PAD. This is called neurogenic claudication. Differentiating symptoms of patients with neurogenic claudication include pain that occurs when standing, pain the is improved when leaning forward, and pain that can only be relieved by sitting.
When seeing a patient with exertional leg pain, it is critical to identify risk factors for vascular disease which including current or prior smoking, high blood pressure, high cholesterol, diabetes, obesity, advancing age, and a family history of PAD, heart disease or stroke. During physical exam, the pulses are palpated. Using a stethoscope, bruits (abnormal sounds in the artery) are listened for. It is extremely important to note that patients may have normal pulses in their feet and still have significant PAD. This is why objective testing is required.
Ankle Brachial Index (ABI), is quick, simple, non-invasive way to evaluate for PAD. This test compares the blood pressure at the ankle with the pressure in the arm. The patient then exercises on the treadmill and the test is repeated. Patients with claudication will show a decrease in the blood pressure at the ankle. An example of a positive exercise ABI is below. Note the drop in leg pressures (red and gold lines).
