Degenerative Changes in Asymptomatic Subjects: A Descriptive Study Examining the Supraspinatus Using Musculoskeletal Sonography in a Young Population.

As many as 96% of persons over age 50 years may have shoulder abnormalities involving the rotator cuff. Many of these individuals remain asymptomatic. In contrast, there is limited research into the prevalence of shoulder pathology in the younger asymptomatic population. The supraspinatus muscle is the most likely candidate for injury within the common "rotator cuff" array of shoulder pathologies. The purpose of this study was to determine, using musculoskeletal sonography and basic clinical/physical screening, whether younger asymptomatic subjects (23.4 ± 4.5 yrs) possess any degenerative changes within the supraspinatus muscle/ tendon complex. Early detection of degenerative changes could set the stage for efforts to slow progression and even prevent the development of functional impairment. Forty-six subjects, having no shoulder pain or known functional impairment volunteered for this assessment. Both shoulders of each subject were assessed using physical screening and musculoskeletal sonography. Results showed that 24% of these asymptomatic shoulders demonstrated degenerative changes detectable by musculoskeletal sonography. None of these changes were identified using common physical exam screenings. The incidence and prevalence of subclinical supraspinatus pathology in young subjects may be significantly greater than expected.

Skin pH changes associated with iontophoresis.

STUDY DESIGN: Randomized controlled trial. The researcher measuring skin pH was blinded to group assignment. OBJECTIVES: To compare the skin surface pH changes associated with iontophoresis. The investigation was designed to address the question of whether significant skin pH changes occur under the cathode on the skin surface when performing iontophoresis and assessed the influence of different electrode-buffering systems intended to stabilize skin pH (surface). BACKGROUND: Whether buffers are needed to stabilize skin pH during iontophoresis has not been thoroughly addressed in the literature. The effectiveness of immobile resins versus simple phosphate buffers is also unclear. METHODS AND MEASURES: Sixty volunteer subjects were administered iontophoresis of normal saline using buffered or nonbuffered electrode systems. Each subject participated in 1 of the 12 doses by electrode conditions (i.e., 5 subjects per group). Surface skin pH was measured before and after iontophoresis with a flat-surface pH electrode in concert with an analog pH meter. The independent variables were electrode type (4 levels) and dosage (3 levels). The dependent variable was the change in skin surface pH. RESULTS: A significant change in skin pH was found only when the treatment dose was 80 mA/minute with a nonbuffered electrode (x = 3.14 +/- 1.09). CONCLUSIONS: The skin pH changes that occur during a properly delivered iontophoresis treatment at dosages of 20 and 40 mA/min were small and not significantly different with or without the addition of buffers. Those pH changes associated with 80 mA/min doses were significantly greater when no buffer was employed but were stabilized by each of the buffers used in the study (preloaded immobile resins or simple phosphates added at point of treatment).

The reliability of selected measures of muscular performance in knee flexion and extension using the hydra-fitness omni tron total power unit: a pilot study.

This research was supported in part by an equipment grant from Hydra-Fitness Industries. Inc., Belton, TX. Thirty-one subjects were included in this investigation (19 female and 12 male). The subjects ranged in age from 19-38 years with a mean age of 25 years. The subjects performed a maximal strength test of knee flexion and extension using the Omni Tron Total Power Unit employing one resistance setting. Values were obtained for eight muscular performance indicators. An identical strength test was repeated the following day. Reliability coefficients were calculated using the two sets of data. Pearson product coefficients for the eight performance indicators ranged from 0.85 to 0.97. Values from test 1 were also compared to test 2 values for significant difference using the student t-test. No significant difference was found (p < 0.05). The authors concluded that, based on the data obtained in this pilot study, the Omni Tron Total Power Unit holds the potential to produce reliable data relating to muscular performance. J Orthop Sports Phys Ther 1989;10(10):418-422.