Int J Sports Med 2015; 36(14): 1201-1205
DOI: 10.1055/s-0035-1555855
Clinical Sciences
© Georg Thieme Verlag KG Stuttgart · New York

Strength and Pain Threshold Handheld Dynamometry Test Reliability in Patellofemoral Pain

R. A. van der Heijden
1   General Practice, Erasmus MC University Medical Centre, Rotterdam, Netherlands
,
T. Vollebregt
1   General Practice, Erasmus MC University Medical Centre, Rotterdam, Netherlands
,
S. M. A. Bierma-Zeinstra
1   General Practice, Erasmus MC University Medical Centre, Rotterdam, Netherlands
,
M. van Middelkoop
1   General Practice, Erasmus MC University Medical Centre, Rotterdam, Netherlands
› Author Affiliations
Further Information

Publication History



accepted after revision 08 June 2015

Publication Date:
30 September 2015 (online)

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Abstract

Patellofemoral pain syndrome (PFPS), characterized by peri- and retropatellar pain, is a common disorder in young, active people. The etiology is unclear; however, quadriceps strength seems to be a contributing factor, and sensitization might play a role. The study purpose is determining the inter-rater reliability of handheld dynamometry to test both quadriceps strength and pressure pain threshold (PPT), a measure for sensitization, in patients with PFPS. This cross-sectional case-control study comprises 3 quadriceps strength and one PPT measurements performed by 2 independent investigators in 22 PFPS patients and 16 matched controls. Inter-rater reliability was analyzed using intraclass correlation coefficients (ICC) and Bland-Altman plots. Inter-rater reliability of quadriceps strength testing was fair to good in PFPS patients (ICC=0.72) and controls (ICC=0.63). Bland-Altman plots showed an increased difference between assessors when average quadriceps strength values exceeded 250 N. Inter-rater reliability of PPT was excellent in patients (ICC=0.79) and fair to good in controls (ICC=0.52). Handheld dynamometry seems to be a reliable method to test both quadriceps strength and PPT in PFPS patients. Inter-rater reliability was higher in PFPS patients compared to control subjects. With regard to quadriceps testing, a higher variance between assessors occurs when quadriceps strength increases.