Affiliations: [a] University Outpatient Clinic Potsdam, Sports Medicine
and Sports Orthopaedics, Potsdam, Germany
Note: [] Corresponding author: Steffen Mueller, University Outpatient
Clinic Potsdam, Sports Medicine and Sports Orthopaedics, Am Neuen Palais 10
Haus 12, D-14469 Potsdam, Germany. Tel.: +49 331 9771161; Fax: +49 331 9771296;
E-mail: stefmue@uni-potsdam.de
Abstract: Background: Isokinetic measurements are widely used to assess
strength capacity in a clinical or research context. Nevertheless, the validity
of isokinetic measures for identifying strength deficits and the evaluation of
therapeutic process regarding different pathologies is yet to be established.
Therefore, the purpose of this review is to evaluate the validity of isokinetic
measures in a specific case: that of muscular capacity in low back pain (LBP).
Methods: A literature search (PubMed; ISI Web of Knowledge; The
Cochrane Library) covering the last 10 years was performed. Relevant papers
regarding isokinetic trunk strength measures in healthy and patients with low
back pain (PLBP) were searched. Peak torque values [Nm] and peak torque
normalized to body weight [Nm/kg BW] were extracted for healthy and PLBP.
Ranked mean values across studies were calculated for the concentric peak
torque at 60°/s as well as the flexion/extension (F/E) ratio. Results: 34 publications (31 flexion/extension; 3 rotation) were
suitable for reporting detailed isokinetic strength measures in healthy or LBP
(untrained adults, adolescents, athletes). Adolescents and athletes were
different compared to normal adults in terms of absolute trunk strength values
and the F/E ratio. Furthermore, isokinetic measures evaluating therapeutic
process and isokinetic rehabilitation training were infrequent in literature (8
studies). Conclusion: Isokinetic measurements are valid for measuring trunk
flexion/extension strength and F/E ratio in athletes, adolescents and
(untrained) adults with/without LBP. The validity of trunk rotation is
questionable due to a very small number of publications whereas no reliable
source regarding lateral flexion could be traced. Therefore, isokinetic
dynamometry may be utilized for identifying trunk strength deficits in healthy
adults and PLBP.
Keywords: Isokinetic, validity, low back pain, peak torque, trunk
