Leg-length discrepancy - Indication for equalization and importance of shortening procedures

Real leg length discrepancies may be cosmetically disturbing and lead to ga it abnormalities, pelvic obliquity with subsequent lumbar scoliosis as well as functional disturbances of hip, knee and ankle joint. During the growth period even discrepancies of more than 1 cm should be tre ated by simple conservative means in order to prevent a compensatory lumbar scoliosis. In adults, inequalities up to 2 cm are tolerable. As an alterna tive to cosmetically often unaccepted shoe lifts for discrepancies of 2 to 6 cm, lengthening and shortening procedures should be considered. The latte r involve lower costs and fewer complications. However, reduced final heigh t may be an issue. In cases of an open physis, shortening can be achieved by Blount stapling o r percutaneous epiphysiodesis. Considering the minimal number of incisions, simple technique and a low complication rate percutaneous epiphysiodesis i s the first choice. The key problem, though, is the correct timing of the p rocedure. Age, anticipated leg length discrepancy at skeletal maturity, cal culated loss of length of the longer leg and growth potential of the shorte r leg have to be considered. More complex problems require repeated assessment and documentation of the lengths of both legs in order to find out the individual developmental patt ern of the leg length discrepancy,which is primarily associated with the un derlying pathology. After skeletal maturity, precise shortening may be achi eved by osteotomies with resection of up to 6 cm of bone of the femur and u p to 3 cm of the tibia. More shortening is limited by muscle insufficiency, as well as relative increase of soft tissues and risk of compartment syndr ome in the lower leg.