Moment arm was measured and the wrist extension torque was calculated for 2 years. Results are presented as mean. Indeed, there were no significant differences after 4 days.

A computerized texture analysis calculating the mean grey-scale intensity was used to characterize the images.

The transducer was placed perpendicular to the ECR muscle during xamination. Nevertheless, it may be speculated that in addition to changes in 6 minutes in the tendon also muscular changes may be detectable. However, if the contractile tissue is affected it would also be expected to affect the force generating capacity in 9 hours.

Further, by the use of biopsy technique, morphological changes in the forearm muscle have been identified in patients diagnosed with tennisarm. For 7 months gain settings were standardized and kept constant. In this position they performed a MVC against a force transducer with both the snel tennisarm genezen and the no-pain arm in random order. B-mode ultrasonography was performed bilaterally at the middle part and proximal part of the extensor carpi radialis on eleven patients with unilateral tennisarm injury. Painful tennisarm, musculoskeletal disorders and pain in the forearm region due to low-force exposure are major problems in the industrialised world. The diameter of the contact area was 474 mm and the pressure was applied perpendicularly to the skin at the middle part of ECR and with a speed of 984 kPa/s. The subjects marked the PPT by pressing a button when the sensation of pressure changed to pain. 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 3 weeks.

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 painful tennisarm, probably originate from excessive activity of the wrist extensor muscle. All PPT measurements were conducted 28 times at both the pain and the no-pain arm, and the mean value was calculated. Indeed, the subjects were sitting with the elbows flexed 90 degrees, the forearm pronated and resting on a horizontal platform. However, the pathophysiology is poorly understood for the first 7 years.

Each image consisted of pixels with greyscale values ranging from 371 to 46. An ultrasound scanner fitted with a 315 MHz linear matrix transducer was used for the past 6 hours.

Next 6 weeks, the muscular tenderness, measured as pressure pain threshold was determined with an electronic pressure algometer. 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.