[Incidence and effect of leg length discrepancy after total hip arthroplasty]. / Incidencia y efecto de la discrepancia en la longitud de la pierna después de la artroplastía total de cadera.

INTRODUCTION: In coxarthrosis pain relief and the restoration of function including leg length are achieved with total hip arthroplasty. Sometimes achieving stability makes it impossible to achieve equal leg length. OBJECTIVE: To determine the incidence of pelvic limb length discrepancy, its effect on function and its emotional effect in a group of patients who underwent total hip arthroplasty. MATERIAL AND METHODS: A total of 252 patients with a diagnosis of grade IV coxarthrosis were assessed. They underwent unilateral primary total hip arthroplasty with a direct lateral approach; 190 were uncemented and 162 hybrid. Limb length was measured from the anterosuperior iliac crest to the medial malleolus of both legs. Patients were divided into four groups depending on leg length discrepancy: A) equal length; B) less than 10 mm; C) more than 10 mm, and D) more than 20 mm. RESULTS: A total of 252 arthroplasties were performed in 252 patients; 194 females (76.98%) and 58 males (23.01%). In 115 patients (45.63%) had a discrepancy < 10 mm; 71 patients (28.17%) > 10 mm; 60 patients (23.80%) did not have length discrepancy, and six patients had > 20 mm of discrepancy with lengthening of the operated limb. CONCLUSIONS: Length discrepancy of the operated limb is reported in the literature. It is a common outcome of primary total hip arthroplasty, and is usually < 10 mm, as reported in world literature.