As the human body uses a mechanical system of muscles and bones to move around, when a person has abnormalities in this system, unusual movements can occur. One such abnormality is the Trendelenburg gait, which is an indication that a person has problems with the hip area. Conditions which can produce the sign include a dislocation of the bones of the hip, or problems with the muscles of the area.
Commonly in medicine, a particular medical technique or diagnostic sign is named after the first person to specify the sign. The gait is named after a man named Friedrich Trendelenburg who described the appearance of an unusual way of walking in certain patients. In 1895, Trendelenburg looked at groups of people who displayed problems with the pelvic area and with walking.
In a healthy person, the two legs carry the weight of the person equally. When a person walks, by necessity he or she takes one foot off the ground per step, and temporarily carries all of the person's weight on one leg. The bones of the pelvis, and the muscles that work in conjunction with the pelvic bone, work in efficient concert with each other. When a person has medical issues with either the bones or the muscles, the weight distribution and movement of the body can become noticeably different.
Usually the pelvis, which is the large, wide bone structure into which both the spine and the legbones connect to, moves up on the side of the body where the foot is lifted up. With this type of gait, the person cannot lift up the side of the pelvis to help raise the foot and transfer the weight to the other leg. Instead, the person's pelvis moves downward, in the opposite manner. This reduces the efficacy of the foot-raising, and the affected person typically bends his or her leg more than usual at the knee to make up for the lack of lift. Other indicators of Trendelenburg gait include short steps on the unaffected side, and a tendency for the person to lean to the affected side while walking.
If a doctor suspects a hip problem in a patient, he or she may perform a Trendelenburg test, which involves the patient standing on one foot. The doctor examines the hip area for a lowering of one side of the pelvis, and also checks for lack of balance. If a patient does exhibit a Trendelenburg gait, he or she may be suffering from several types of illness.
Breakages or dislocations of the pelvis are possible causes of a Trendelenburg gait. Alternatively, the muscles of the region may be involved and a variety of muscle-wasting conditions can cause the problem. Nerve damage is another possibility, as the nerves control the movement of the muscles. Polio is a nerve condition that can display Trendelenburg gait as a symptom, although this disease is very uncommon in countries with polio vaccination programs.