The relation of peripheral and central sensitization to muscle co-contraction: the MOST study. Issue 9 (September 2020)

• Record Type: Journal Article
• Authors: Stefanik, J.J.; Frey-Law, L.; Segal, N.A.; Niu, J.; Lewis, C.E.; Nevitt, M.C.; Neogi, T.
• Is Part Of: Osteoarthritis and cartilage. Volume 28:Issue 9(2020)
• Page Start: 1214
• Page End: 1219
• Publication Date: 2020-09
• Subjects: Knee osteoarthritis -- Sensitization -- Muscle -- Co-contraction; Osteoarthritis -- Periodicals; Cartilage -- Periodicals; Osteoarthritis -- Periodicals; Cartilage -- Periodicals; Arthrose -- Périodiques; Articulations -- Maladies -- Périodiques; 616.7223005
• DOI: 10.1016/j.joca.2020.06.002
• Languages: English
• ISSNs: 1063-4584

Abstract

Summary: Objective: To examine the relation of pain sensitization to altered motor activity in knee OA as assessed by hamstrings muscle co-contraction during maximal effort knee extension. Design: Medial, lateral, and overall hamstring co-contraction was assessed in the Multicenter Osteoarthritis (MOST) Study cohort using electromyography during isokinetic knee extension at 60°/second. Mechanical temporal summation of pain (TS) was assessed at the right wrist and pressure pain thresholds (PPT) were assessed at the patellae; PPTs were categorized into sex-specific tertiles. Muscle co-contraction was categorized into age- and sex-specific tertiles. We evaluated the relation of measures of sensitization to muscle co-contraction using a generalized logistic regression model. Results: 1633 participants were included: mean age and BMI was 67.3 ± 7.7 years and 30.3 ± 5.6 kg/m 2, respectively; 58% were female. Presence of TS was associated with higher overall (OR 1.3, 95% confidence interval (CI) (1.0–1.8)), medial (1.4 (1.0–1.9), and lateral (1.3 (1.0, 1.9)) hamstring co-contraction. The lowest PPT tertile (greater sensitivity) was associated with higher overall (1.5 (1.0, 2.3)) and medial (1.5 (1.0, 2.3)) hamstring co-contraction compared with those in the highest PPT tertile. Conclusion: Greater pain sensitization, as assessed by presence of TS at the wrist and low patellar PPT, was associated with greater overall and medial hamstring co-contraction during knee extension. This provides support to the possibility that peripheral and/or central nervous system alterations may not only affect pain sensitivity, but also motor function.