Individuals with Persistent Greater Trochanteric Pain Syndrome Exhibit Impaired Pain Modulation, as well as Poorer Physical and Psychological Health, Compared with Pain-Free Individuals: A Cross-Sectional Study.

OBJECTIVES: To compare physical, sensory, and psychosocial factors between individuals with greater trochanteric pain syndrome and controls and to explore factors associated with pain and disability. DESIGN: Cross-sectional study. SETTING: General community. SUBJECTS: Patients with persistent, clinically diagnosed greater trochanteric pain syndrome and healthy controls. METHODS: Participants completed tests of thermal and pressure pain threshold, conditioned pain modulation, temporal summation, muscle strength, physical function, physical activity, psychological factors, and health-related quality of life. Standardized mean differences between groups were calculated, and multiple linear regression identified factors associated with pain and disability. RESULTS: Forty patients (95% female, average [SD] age = 51 [9] years) and 58 controls (95% female, average [SD] age = 53 [11] years) were included. Heat pain threshold, temporal summation, and pain catastrophizing were not different between groups. Compared with controls, patients displayed significantly poorer quality of life (standardized mean difference = -2.66), lower pressure pain threshold locally (-1.47, remotely = -0.57), poorer health status (-1.22), impaired physical function (range = 0.64-1.20), less conditioned pain modulation (-1.01), weaker hip abductor/extensor strength (-1.01 and -0.59), higher depression (0.72) and anxiety (0.61) levels, lower cold pain threshold locally (-0.47, remotely = -0.39), and less time spent in (vigorous) physical activity (range = -0.43 to -0.39). Twenty-six percent of pain and disability was explained by depression, hip abductor strength, and time to complete stairs. CONCLUSIONS: Patients with greater trochanteric pain syndrome exhibited poorer health-related quality of life, physical impairments, widespread hyperalgesia, and greater psychological distress than healthy controls. Physical and psychological factors were associated with pain and disability.