Low Back Pain (LBP) is one of the most significant musculoskeletal disorders associated
with considerable disability and economic losses. There are various methods for treating
LBP. Conservative therapy such as non-steroid anti-inflammatory drugs (NSAIDs), bed
rest, physiotherapy (PT) and in severe and disabling conditions invasive methods (i.e.
surgery) are used the main objective of this research was to identify the functional
differences between normal and LBP patients and identify the efficacy of treatment.
This study was quasi-experimental design study which was performed on 30 (18
normal and 12 LBP patients) females with mean age of 35.70± 4.69 years using
Isostation B200 dynamometer. Evaluation included isometric, range of motion (ROM)
and dynamic tests. Visual analog scale for pain (VAS) was also used in the study group.
The statistic analysis was performed with non-parametric tests of Mann-Whitney and
Wilcoxon. All parameters related to motor output and movement patterns were
significantly decreased in LBP patients (P<.001 for velocity and maximum isometric
torque (MIT) of ext, P<.05 for others). Bedrest produced a significant increase in MIT
of extension andIlexion, average isoinertial Ext torque and extension work (P<.05) , but
ROM and flexion phase variables wasnt significantly changed. Physiotherapy produced
a significant increase in pain reduction, MIT of Ext and flex, velocity, work, power and
ROM in both of Ext and flex phases (P<.05).
There was muscle inhibition (especially extensors) and decrease in all parameters
of motor output and movement patterns due to pain. Bedrest in subacute patients
tended to decrease pain and significantly increase muscle relaxation. It appears that PT
was more efficient than bedrest because in addition to significant pain reduction and
muscle relaxation, it produced an increase in movement patterns. It is suggested that in
the treatment of LBP patients, electrotherapy and movement and/or exercise therapy in
suitable time, is effective in this regard.