For many decades, many doctors of chiropractic (DCs) have “measured” the leg lengths of their patients. It is important to understand that “measuring” in almost all of these cases actually meant a visual inspection (looking at) of the heels of a patient lying prone (face down). If one heel appeared to extend farther than the other, then the patient was said to have a “short leg”.
In most cases, a DC, finding a “short leg”, would adjust the spine of the patient, immediately recheck the leg length and find that the legs were even. How could that be?
The distinction that is not often made in chiropractic or orthopedic practice is between an anatomical short leg (ASL) and a physiological short leg (PSL).
An ASL can occur from polio. It can occur from trauma that results in leg fracture and shorting of bone. An anatomical leg length discrepancy is a true difference in length and can be measured using x-ray.
A PSL is not truly short, but rather one side is drawn up in relation to the other by muscular contraction or shortening of connective tissues. When a patient with a “short leg” is adjusted, thereby evening the leg length, what the DC has done is to balance the muscles that support the legs, or to release connective tissue restrictions. A PSL is extremely common.
When a PSL is resolved by chiropractic treatment, the resolution is almost always temporary. There are many factors that result in muscle imbalance and connective tissue asymmetry in the lower extremities, and these must be dealt with to attempt to maintain an even physiologic leg length.
It is valuable to understand that a PSL is just a sign of muscle and/or connective tissue imbalance. It is not the problem.
Rather than checking for a PSL, a thoughtful DC could check for muscle and connective tissue imbalance; the real causes of the PSL. That same thoughtful DC could treat the patient for the imbalance, and then instruct the patient about the causes and self-care measures for resolving the imbalance.