The Influence of Hip and Knee Joint Angles on Quadriceps Muscle-Tendon Unit Properties during Maximal Voluntary Isometric Contraction

Int J Environ Res Public Health. 2023 Feb 23;20(5):3947. doi: 10.3390/ijerph20053947.

Abstract

Determining how the quadriceps femoris musculotendinous unit functions, according to hip and knee joint angles, may help with clinical decisions when prescribing knee extension exercises. We aimed to determine the effect of hip and knee joint angles on structure and neuromuscular functioning of all constituents of the quadriceps femoris and patellar tendon properties. Twenty young males were evaluated in four positions: seated and supine in both 20° and 60° of knee flexion (SIT20, SIT60, SUP20, and SUP60). Peak knee extension torque was determined during maximal voluntary isometric contraction (MVIC). Ultrasound imaging was used at rest and during MVIC to characterize quadriceps femoris muscle and tendon aponeurosis complex stiffness. We found that peak torque and neuromuscular efficiency were higher for SUP60 and SIT60 compared to SUP20 and SIT20 position. We found higher fascicle length and lower pennation angle in positions with the knee flexed at 60°. The tendon aponeurosis complex stiffness, tendon force, stiffness, stress, and Young's modulus seemed greater in more elongated positions (60°) than in shortened positions (20°). In conclusion, clinicians should consider positioning at 60° of knee flexion rather than 20°, regardless if seated or supine, during rehabilitation to load the musculotendinous unit enough to stimulate a cellular response.

Keywords: mechanical properties; moment-angle relationship; muscle length.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Isometric Contraction* / physiology
  • Knee / physiology
  • Knee Joint / physiology
  • Male
  • Muscle, Skeletal / physiology
  • Quadriceps Muscle* / physiology
  • Tendons / physiology

Grants and funding

This research was funded by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brasil (CAPES Finance Code 001), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq process no: 404746/2018-7; 312136/2018-8; 309435/2020-0 and 310269/2021), the Fundação de Amparo à Pesquisa do Distrito Federal (FAPDF process no. 00193.0000168/2019-87, Edital 11/2022 process no 00193-00001219/2022-93), Decanato de Pesquisa e Inovação (DPI Edital 04/2019), and Decanato de Pós-Graduação (Edital 03/2021; Edital 04/2021; Edital 006/2021—Fellowship 23106.104941/2021-71). The authors would like to thank the Region Bourgogne-Franche-Comté (2020Y-22065 and 2022Y-13186), and the National Council for Scientific and Technological Development – CNPq (200391/2022-4) for funding this research.