title: The effect of peripheral neuropathy on lower limb muscle strength in diabetic individuals.
abstract: BACKGROUND
  Skeletal muscle strength is poorly described and understood in diabetic participants with diabetic peripheral neuropathy. This study aimed to investigate the extensor and flexor torque of the knee and ankle during concentric, eccentric, and isometric contractions in men with diabetes mellitus type 2 with and without diabetic peripheral neuropathy.
  
  
  METHODS
  Three groups of adult men (n=92), similar in age, body mass index, and testosterone levels, were analyzed: 33 non-diabetic controls, 31 with type 2 diabetes mellitus, and 28 with diabetic peripheral neuropathy. The peak torques in the concentric, eccentric, and isometric contractions were evaluated using an isokinetic dynamometer during knee and ankle flexion and extension.
  
  
  RESULTS
  Individuals with diabetes and diabetic peripheral neuropathy presented similar low concentric and isometric knee and ankle torques that were also lower than the controls. However, the eccentric torque was similar among the groups, the contractions, and the joints.
  
  
  CONCLUSIONS
  Regardless of the presence of peripheral neuropathy, differences in skeletal muscle function were found. The muscle involvement does not follow the same pattern of sensorial losses, since there are no distal-to-proximal impairments. Both knee and ankle were affected, but the effect sizes of the concentric and isometric torques were found to be greater in the participants' knees than in their ankles. The eccentric function did not reveal differences between the healthy control group and the two diabetic groups, raising questions about the involvement of the passive muscle components.
authors.affiliation: Laboratory of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, SP, Brazil.
authors.forename: Jean P
authors.initials: JP
authors.lastname: Ferreira
authors.affiliation: Physical Therapy, Speech and Occupational Therapy Department, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Cristina D
authors.initials: CD
authors.lastname: Sartor
authors.affiliation: Department of Medicine, Federal University of São Carlos, São Carlos, SP, Brazil.
authors.forename: Ângela M O
authors.initials: ÂM
authors.lastname: Leal
authors.affiliation: Physical Therapy, Speech and Occupational Therapy Department, School of Medicine, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Isabel C N
authors.initials: IC
authors.lastname: Sacco
authors.affiliation: Laboratory of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, SP, Brazil.
authors.forename: Tatiana O
authors.initials: TO
authors.lastname: Sato
authors.affiliation: Laboratory of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, SP, Brazil.
authors.forename: Ivana L
authors.initials: IL
authors.lastname: Ribeiro
authors.affiliation: Laboratory of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, SP, Brazil.
authors.forename: Alice S
authors.initials: AS
authors.lastname: Soares
authors.affiliation: Laboratory of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, SP, Brazil.
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Cunha
authors.affiliation: Laboratory of Skeletal Muscle Plasticity, Department of Physical Therapy, Federal University of São Carlos, SP, Brazil. Electronic address: tania@ufscar.br.
authors.forename: Tania F
authors.initials: TF
authors.lastname: Salvini
mesh_terms: D000328:Adult; D000368:Aged; D000842:Ankle / Q000503:physiopathology; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007717:Knee / Q000503:physiopathology; D035002:Lower Extremity / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology; D016059:Range of Motion, Articular; D019415:Torque
keywords: Diabetes; Low limbs; Motor function; Muscle function; Muscle strength; Polyneuropathy