Cervical strength of young adults in sagittal, coronal, and intermediate planes.

摘要

OBJECTIVES: To measure the cervical isometric force generation capacity of men and women reliably while seated in upright neutral posture. DESIGN: The cervical muscle isometric strength was determined in flexion, extension, lateral flexion, anterolateral flexion and posterolateral extensions in an upright seated neutral posture. For this measurement a device was designed, fabricated and its reliability established. BACKGROUND: To-date only a few studies on cervical strength data have been published. Of these, validity of some data is suspected due to the use of unstandardized methodology. No studies were identified which reported cervical strengths in lateral and oblique planes. METHODS: A testing device consisting of sturdy, stable and strong telescopic adjustable square metal tube was firmly bolted in the floor. Another rotating metal tube was pivoted and adjustably counterweighted and attached to an immovable object with a load cell in its path. Using a horizontal bar upholstered at the terminal endattached to the rotating tube 40 young subjects were tested. They exerted their maximal voluntary isometric contraction in flexion, extension, lateral flexion, anterolateral flexion, and posterolateral extension bilaterally. RESULTS: Cervical muscle strength was maximum in extension and minimal in anterolateral flexion (which was very close to flexion strength). With progressive change in direction towards posterior region the strength progressively increased. There was a significant difference between male and female strengths (P < 0.01). The flexion/extension ratio of males was 1:1.37 and for females 1:1.79. There was a significant difference in strength values in different directions (P < 0.01). CONCLUSIONS: The cervical strength is direction dependent. The extension generates maximum force and flexion close to minimum. A progressive change from anterior to posterior direction generates increasing force. RELEVANCE: There is insufficient information regarding cervical strength, which may at least indirectlyand in part, indicate the force bearing capacity of cervical musculature. The present study furnishes some data to this end.