Isokinetic testing of flexor and extensor muscles in athletes suffering from low back pain

The aim of the study was to verify the usefulness of isokinetic testing in athletes with chronic low back pain (LBP) to obtain quantitative information for rehabilitation purposes.

a comparative study.

Physiotherapy Department--Institute of Sports Medicine in Italy.

50 men, aged 25-65, practising running, cycling, triathlon, tennis, soccer, basketball, volleyball, skiing and golf. The patients were divided into two groups. Group A was treated for 3 months with postural exercises 2 or 3 times a week. Group B was treated for the same period of time with resistive exercises performed by resorting to specific machines.

Before and after treatment, trunk muscle strength was evaluated by means of an isokinetic test carried out in a seated position. The isokinetic measurements used were peak torque (PT), work, power-in the best repetition and total work (TW) in four repetitions. Both the pain and the functional impairment during physical activity was evaluated by subjective visual analogic scale.

The PT showed a parallel increase in flexor and extensor muscles in Group A. In Group B it increased by 32.2% at 60 degrees/s and 44.1% at 120 degrees/s as for the extensor muscles while the flexion-to-extension ratio decreased significantly. The TW registered a bigger percentage increase in both groups (+21% at 60 degrees/s and +20.4% at 120 degrees/s in Group A; +36.5% at 60 degrees/s and +50.3% at 120 degrees/s in Group B).

The two rehabilitation programmes had the same effect on the course of LBP, but in Group B we observed a bigger increase in strength which could be potentially useful during a sports activity.