Reliability of isometric strength measurements in trunk and neck region: patients with chronic neck pain compared with pain-free persons

Scheuer R, Friedrich M. Reliability of isometric strength measurements in trunk and neck region: patients with chronic neck pain compared with pain-free persons.

Objective

Evaluation of reliability of isometric strength measurements in the neck and trunk region and comparison of these measurements between patients with chronic neck pain and pain-free subjects.

Design

Nonrandomized controlled trial.

Setting

Institutional practice.

Participants

Patients with neck pain (n=53) and pain-free persons (n=42) (mean age ± SD, 49.7±10.74 vs 48.7±12.02; women, 73% vs 71%).

Interventions

Strength of flexion, extension, and lateral flexion in the neck and trunk were measured. Each participant underwent 2 measurement passes on each of 2 examination days; 3 were performed by the same investigator, 1 by a second.

Main Outcome Measures

Intrarater (short-term and long-term) and interrater reliability, differences in strength between both groups of probands.

Results

Reliability in both groups ranged from substantial to almost perfect (intraclass correlation coefficient: patients, .76–.89; control group, .80–.88). The patients' strength in the neck and trunk was significantly below that of the control group (P<.002).

Conclusions

Isometric strength measurement is a reliable and feasible way to estimate the possible benefit of specific strengthening programs. Patients with chronic neck pain showed strength deficits in all measured regions.