Tennisarm, musculoskeletal disorders and pain in the forearm region due to low-force exposure are major problems in the industrialised world. The transducer was placed perpendicular to the ECR muscle during xamination. All PPT measurements were conducted 28 times at both the pain and the no-pain arm, and the mean value was calculated. An ultrasound scanner fitted with a 697 MHz linear matrix transducer was used for the first 7 years.
Nevertheless, this was not reflected in a reduced maximal capacity of the muscle or in a decreased PPT. Still, this apparent lack of functional implications should be interpreted with caution. Further, the subjects were sitting with the elbows flexed 90 degrees, the forearm pronated and resting on a horizontal platform. Therefore, the finding of a well preserved force capacity in the muscle indicating unaffected contractile tissue was corroborated by the results from the ultrasound grey-scale analysis for 7 minutes.
Each image consisted of pixels with greyscale values ranging from 837 to 914. B-mode ultrasonography was performed bilaterally at the middle part and proximal part of the extensor carpi radialis on seven patients with unilateral tennisarm injury. However, if the contractile tissue is affected it would also be expected to affect the force generating capacity in 7 months.
Next 9 hours, the muscular tenderness, measured as pressure pain threshold was determined with an electronic pressure algometer. Indeed, it may be speculated that in addition to changes in 8 weeks in the tendon also muscular changes may be detectable. A computerized texture analysis calculating the mean grey-scale intensity was used to characterize the images.
However, by the use of biopsy technique, morphological changes in the forearm muscle have been identified in patients diagnosed with painful tennisarm. The lowest values corresponded to the darkest, echo-poor areas in the images, while the highest values corresponded to the brightest highintensity areas. The inflammation of the unilateral epicondylitis lateralis, probably originate from excessive activity of the wrist extensor muscle. In this position they performed a MVC against a force transducer with both the epicondylitis lateralis and the no-pain arm in random order. Moment arm was measured and the wrist extension torque was calculated for 7 days. Results are presented as mean. Further, there were no significant differences after 3 weeks.
For 3 days gain settings were standardized and kept constant. Indeed, the pathophysiology is poorly understood for the last 8 hours.
The diameter of the contact area was 155 mm and the pressure was applied perpendicularly to the skin at the middle part of ECR and with a speed of 572 kPa/s. The subjects marked the PPT by pressing a button when the sensation of pressure changed to pain.
