Thesis (MScPhysio)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Aims: To assess the effect of a vertical height adjustment of the chair and visual display unit (VDU) on work related upper quadrant musculoskeletal pain (WRUQMP) and sitting comfort in computer users. The upper quadrant refers to the occiput, cervical and upper thoracic spine including the clavicles and scapulae. Methods: An N=1 study was conducted using the ABC design whereby an ergonomic workstation adjustment, of VDU and chair height, was compared to the subject’s usual workstation settings. Pain and sitting comfort were measured using visual analogue scales (VAS). The subject was assessed over the four week phases as she performed her typical VDU work. The results were compiled and tabulated. Results: Both the mean and variance in pain intensity decreased after the workstation intervention. A deterioration was noted in sitting comfort. Conclusion: The vertical height adjustment of the chair and VDU may have contributed to a decrease in WRUQMP in this subject. This safe, economical workstation intervention may be a practical management option for the computer user suffering from WRUQMP. Further research into the measurement of comfort whilst sitting at a computer workstation, is recommended. / AFRIKAANSE OPSOMMING: Doelwitte: Om die effek te bepaal van n vertikale aanpassing van die stoel en beeldskerm van rekenaargebruikers op werksverwandte boonste kwadrant muskuloskeletale pyn en sitgemak. Die boonste kwadrant verwys na die oksiput, servikale en boonste torakale werwelkolom en sluit ook die klavikel en skapula in. Methode: Die N=1 studie is onderneem met gebruik van die ABC ontwerp in terme waarvan n ergonomiese aanpassing van stoel en beeldskerm vergelyk is met die normale gebruik van die deelnemer. Pyn en sitgemak is gemeet deur die gebruik van die Visueel analoogskaal. Die interwensies is ge-evalueer oor vierweekfases tydens normale rekenaar gebruik van die deelnemer. Die resultate is saamgestel en getabuleer. Uitkoms: Beide die gemiddelde en veranderlike pynintensiteit het verminder nadat die werkstasie aangepas is. Geen verbetering in sitgemak is opgemerk nie. Gevolgtrekking: Die vertikale hoogte-aanpassing van die stoel en beeldskerm het moontlik bygedra tot die verminderde pynvlakke in hierdie deelnemer. Hierdie veilige, ekonomiese verstelling is moontlik n praktiese beheeropsie vir rekenaargebruikers wat werksverwandte boonste kwadrant muskuloskeletale pyn verduur. Verder studie in die meet en waarneming van sitgemak tydens rekenaarwerk is nodig.