Matt Adams, Sergio Florian, Troy Kurtz, Mike Martinez, R. Wesley Swen, Gail Polvoorde. The Effects of Aging on the Scapulohumeral Reflex of Older Adults. Doctor of Physical Therapy Research Reports 2006; Loma Linda University School of Allied Health Professions.
( 6/2004 - 6/2006 )
Background and Purpose. The purpose of this study was to document the occurrence rate of the scapulohumeral reflex for normal subjects between 40 and 80 years of age. We hypothesized that reflexes would diminish as the age of the subjects increased. Subjects. Subjects were recruited from senior centers, fitness clubs, convalescent homes, and the community. Subjects were between 40 and 80 years old. They were divided into four groups of 10. Group 1 ranged in age from 40-49 years, group 2 from 50-59, group 3 from 60-69, and group 4 from 70-79 years. Subjects were free of cervical and shoulder musculoskeletal or neural pathologies. Gender was not a factor in subject selection. Methods. Each subject’s right upper extremity reflexes (C5, C6, and C7) were tested along with his/her scapulohumeral reflex (C4). The subjects were placed sitting with arms resting at their sides. Six taps were administered with a Babinski/Rabiner reflex hammer and the resulting reflex was classified into one of four reflex grades. Shoulder elevation and abduction of any grade except 0 was considered to be a positive response for scapulohumeral reflex. Results. Scapulohumeral reflex was present in 35 of our 40 subjects (878.5%). In the 70-79 year old age group, scapulohumeral reflex was present in only 80% of the subjects. There was not a significant correlation between age and scapulohumeral reflex grade (r=-.21, p=.20). A Chi-square test also showed no significant association between age group and scapulohumeral reflex grade (p=.57). Discussion and Conclusion. Our hypothesis stated that reflexes would diminish with age among the elderly population, however, there was not a significant correlation between age and scapuloumeral reflex grade. The occurrence rate of the scaulohumeral reflex was greater than that of the triceps reflex, which is used in standard clinical neurological testing. Clinically, the scapulohumeral reflex may be reliable, along with the biceps, brachioradialis, and triceps reflex, as an evaluation to assess upper extremity neurological integrity.