Disability Self-Assessment and Upper Quarter Muscle Balance in Females
type: CreativeWork
description: Background and Purpose. This study compared upper quarter muscle balance of working female dental hygienists and non-dental hygiene females who had no history of upper quarter pathology. The upper quarter was operationally defined as the shoulder and neck region; and muscle balance, as muscular flexibility and muscular performance. Muscular performance was operationally defined as a combination of strength and endurance. Subjects. The study group consisted of 41 working dental hygienists between the ages of 22 and 60 years with a mean age of 38 years. The control group consisted of 46 non-dental hygienists between the ages of 20 and 54 years with a mean age of 29 years. Methods.Passive muscular flexibility of the upper trapezius and levator scapula was measured using an inclinometer. Passive muscle length testing of the pectoralis major and minor was assessed using the Kendall Technique. Subjects were also instructed to maintain four different positions using isometric muscular contractions, each position representing a different group of scapular stabilizers. Muscle performance was measured by timing the duration, in seconds, of each of the four positions held. Additionally, all subjects filled out the Northwick Park Neck Pain Questionnaire (NPNPQ). Analysis of Covariance (ANCOVA) was used during data analysis to adjust for the age difference between groups. Results. The results of this study suggest that female dental hygienists are more likely than non-dental hygiene females to develop tightness in the upper trapezius (p=0.007) and the levator scapula (p=0.01) of the non-dominant upper quarter. Muscle performance trends in the dental hygiene group for the serratus anterior position, upper trapezius and levator scapula position, and the pectoralis minor and lower trapezius position supported popular muscle balance theory that short muscles remain strong while lengthened muscles become weaker. Statistical significance was not achieved in any of the muscular perform…
abstract: Background and Purpose. This study compared upper quarter muscle balance of working female dental hygienists and non-dental hygiene females who had no history of upper quarter pathology. The upper quarter was operationally defined as the shoulder and neck region; and muscle balance, as muscular flexibility and muscular performance. Muscular performance was operationally defined as a combination of strength and endurance. Subjects. The study group consisted of 41 working dental hygienists between the ages of 22 and 60 years with a mean age of 38 years. The control group consisted of 46 non-dental hygienists between the ages of 20 and 54 years with a mean age of 29 years. Methods.Passive muscular flexibility of the upper trapezius and levator scapula was measured using an inclinometer. Passive muscle length testing of the pectoralis major and minor was assessed using the Kendall Technique. Subjects were also instructed to maintain four different positions using isometric muscular contractions, each position representing a different group of scapular stabilizers. Muscle performance was measured by timing the duration, in seconds, of each of the four positions held. Additionally, all subjects filled out the Northwick Park Neck Pain Questionnaire (NPNPQ). Analysis of Covariance (ANCOVA) was used during data analysis to adjust for the age difference between groups. Results. The results of this study suggest that female dental hygienists are more likely than non-dental hygiene females to develop tightness in the upper trapezius (p=0.007) and the levator scapula (p=0.01) of the non-dominant upper quarter. Muscle performance trends in the dental hygiene group for the serratus anterior position, upper trapezius and levator scapula position, and the pectoralis minor and lower trapezius position supported popular muscle balance theory that short muscles remain strong while lengthened muscles become weaker. Statistical significance was not achieved in any of the muscular perform…
author: Johnson, Eric Glenn
language: English
keywords: Physical Therapy, Muscular Diseases -- rehabilitation; Muscle Fatigue -- physiology; Shoulder Pain -- physiology; Shoulder Pain -- rehabilitation; Neck Pain -- physiology; Neck Pain -- rehabilitation; Postural Balance -- physiology; Dental Hygienists; Female; Occupational Diseases; Disability Evaluation; Self-Assessment; Isometric Contraction; Chi-Square Distribution; Factor Analysis, Statistical.
date published: 2001-06-01T07:00:00Z
date modified: 2026-07-24T02:53:31Z
provider: Loma Linda University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Loma Linda University