Predictors of Gait Recovery after Artificial Femoral Head Replacement in Patients with Femoral Neck Fracture: A Retrospective Study Focusing on Acute Postoperative Pain and Lower-limb Muscle Strength

Abstract

[Purpose] To examine the level of acute postoperative pain and lower-limb muscle strength as predictors of gait recovery in patients with femoral neck fracture undergoing artificial femoral head replacement. [Subjects and Methods] Among 48 patients who had suffered femoral neck fracture due to injury and undergone artificial femoral head replacement, 31 were studied, excluding those meeting the exclusion criteria. Acute postoperative pain was measured on the lesional side with maximal loading using the Verbal Rating Scale on Day 7 after surgery. On the same day, the lower-limb muscle strength was also evaluated by measuring the isometric knee extension muscle strength-body weight ratio. [Results] In both <early gait independence> and <gait independence> groups, moderate pain when loading and an isometric knee extensor strength-body weight ratio of 16.8% showed high prediction accuracy. [Conclusion] The results suggest that the number of days needed to achieve gait independence is influenced by the level of acute postoperative pain and knee extensor strength.