Muscle Atrophy, Voluntary Activation Disturbances, and Low Serum Concentrations of IGF-1 and IGFBP-3 Are Associated With Weakness in People With Chronic Stroke

Marcela de Abreu Silva-Couto; Christiane Lanatovitz Prado-Medeiros; Ana Beatriz Oliveira; Carolina Carmona Alcântara; Araci Teixeira Guimarães; Tania de Fatima Salvini; Rosana Mattioli; Thiago Luiz de Russo

doi:10.2522/ptj.20130322

Figures

Figure 1.

Flowchart of the participants through the study. T=total group, H=hemiparetic group, and C=control group. FAC=Functional Ambulation Categories, COPD=chronic obstructive pulmonary disease.

Figure 2.

Quadriceps and hamstring muscle volume. Representative magnetic resonance images from the control group (A) and the hemiparetic group (B). Bar: 15 cm. (C) Quadriceps muscle volumes (RF=rectus femoris, VM=vastus medialis, VI=vastus intermedius, VL=vastus lateralis). (D) Hamstring muscle volumes (SS=semitendinosus and semimembranosus, BF=biceps femoris). *P<.05 compared with control group. Note the selective atrophy in the paretic limb of the VM, VI, BF, and SS muscles. CL=control limb, NPL=nonparetic limb, PL=paretic limb.

Figure 3.

Serum concentration of (A) insulinlike growth factor 1 (IGF-1) and (B) insulinlike growth factor–binding protein 3 (IGFBP-3). *P<.05 compared with control group. Values are presented as the mean ± standard deviation.

Figure 4.

Muscle activation during maximal voluntary concentric contraction. EMG=electromyography (in millivolts), CL=control limb, NPL=nonparetic limb, PL=paretic limb, RF=rectus femoris, VM=vastus medialis, VL=vastus lateralis, BF=biceps femoris; ST=semitendinosus. *P<.0017. Comparisons are indicated by brackets. Note the decreased RF muscle activation in the PL during concentric extension and decreased BF and ST activity in the PL during concentric flexion.

Tables

Table 1.

Demographic and Functional Description of the Sample^{^a}

↵^a Measurements are reported as mean (SD). SSQLS=Stroke-Specific Quality of Life Scale³⁴; FMA= Fugl-Meyer Assessment³²; FAC=Functional Ambulation Categories²³: 0=nonfunctional ambulation, 1=ambulatory, dependent for physical assistance, level 2, 2=ambulatory, dependent for physical assistance, level 1, 3=ambulatory, dependent for supervision, 4=ambulatory, independent, level surfaces only, 5=ambulatory, independent; MAS=Modified Ashworth Scale²²: 0=no increase in muscle tone, 1=slight increase in muscle tone, manifested by a catch and release or by minimal resistance at the end of the range of motion [ROM], 1+=slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder of the ROM, 2=more marked increase in muscle tone through most of the ROM, but affected parts easily moved, 3=considerable increase in muscle tone, passive movement difficult, 4=affected parts rigid in flexion or extension; SF-36=36-Item Short-Form Health Survey³⁵; PAQB=Physical Activity Questionnaire Basal.²⁴ *Significantly different compared with control group.

Table 2.

Assessment With Isokinetic Dynamometer^{^a}

↵^a Measurements are reported as mean (SD). CL=control limb, NPL=nonparetic limb, PL=paretic limb; *Significantly different compared with control limb (P<.05). ^†Significantly different compared with nonparetic limb (P<.05).

Supplementary Data

eFigure

Files in this Data Supplement:

eFigure (PDF) (123 KB) - This PDF contains the following eFigure:
- eFigure. Muscle activation during maximal voluntary eccentric contraction.

Vol 94 Issue 7 Table of Contents

Issue highlights

Muscle Atrophy, Voluntary Activation Disturbances, and Low Serum Concentrations of IGF-1 and IGFBP-3 Are Associated With Weakness in People With Chronic Stroke

Marcela de Abreu Silva-Couto, Christiane Lanatovitz Prado-Medeiros, Ana Beatriz Oliveira, Carolina Carmona Alcântara, Araci Teixeira Guimarães, Tania de Fatima Salvini, Rosana Mattioli, Thiago Luiz de Russo

Physical Therapy Jul 2014, 94 (7) 957-967; DOI: 10.2522/ptj.20130322