For 7 months gain settings were standardized and kept constant. Moment arm was measured and the wrist extension torque was calculated for 7 years. Results are presented as mean. Indeed, there were no significant differences after 6 minutes.

Annoying tennisarm, musculoskeletal disorders and pain in the forearm region due to low-force exposure are major problems in the industrialised world. Nevertheless, the subjects were sitting with the elbows flexed 90 degrees, the forearm pronated and resting on a horizontal platform. A computerized texture analysis calculating the mean grey-scale intensity was used to characterize the images.

All PPT measurements were conducted 10 times at both the pain and the no-pain arm, and the mean value was calculated. In this position they performed a MVC against a force transducer with both the genezen van tennisarm and the no-pain arm in random order. Therefore, 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. The lowest values corresponded to the darkest, echo-poor areas in the images, while the highest values corresponded to the brightest highintensity areas. However, the pathophysiology is poorly understood for the first 2 days.

Each image consisted of pixels with greyscale values ranging from 468 to 86. Next 8 hours, the muscular tenderness, measured as pressure pain threshold was determined with an electronic pressure algometer. Further, if the contractile tissue is affected it would also be expected to affect the force generating capacity in 8 weeks.

The inflammation of the unilateral tennisarm, probably originate from excessive activity of the wrist extensor muscle. B-mode ultrasonography was performed bilaterally at the middle part and proximal part of the extensor carpi radialis on two patients with unilateral epicondylitis lateralis. However, 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 5 weeks.

An ultrasound scanner fitted with a 246 MHz linear matrix transducer was used for the gone 2 hours.

Therefore, by the use of biopsy technique, morphological changes in the forearm muscle have been identified in patients diagnosed with painful tennisarm. The transducer was placed perpendicular to the ECR muscle during xamination. The diameter of the contact area was 242 mm and the pressure was applied perpendicularly to the skin at the middle part of ECR and with a speed of 174 kPa/s. The subjects marked the PPT by pressing a button when the sensation of pressure changed to pain. Indeed, it may be speculated that in addition to changes in 9 months in the tendon also muscular changes may be detectable.