Postural and Muscle Fatigue Analysis of Endodontic Residents: A Research Proposal
Conditions: Musculoskeletal System Disease, Position Sense Disorders, Symptoms and Signs, Postural; Defect, Endodontic Disease
Sponsor: Universidad Europea de Madrid

Postural and Muscle Fatigue Analysis of 
Endodontic Residents 
 
Study Protocol  
February 2024 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

STUDY PROTOCOL  
Objective: evaluate the working position adopted during an endodontic procedure and to 
determine the perception of symptoms of musculoskeletal disorders in first and second year 
students of the Master in Advanced Endodontics at the European University of Madrid (UEM), 
using the standardised Nordic Kuorinka questionnaire supplemented by a form with socio-
demographic variables 
Desing: The study was a descriptive observational cross-sectional study, the data were collected 
by means of surveys, during from March to May 2024. 
The unit of analysis was the 1st and 2nd year students of the Master's Degree in Endodontics of 
the European University of Madrid (UEM), who had completed the two years of the annual 
teaching period of clinical practice during the years 2022/24.  
Subjects previously diagnosed with a musculoskeletal disorder, with musculoskeletal congenital 
disorders, who had suffered previous trauma affecting the musculoskeletal system, pregnant 
women in their third trimester and subjects who refused to participate in the study were 
excluded.  
Methods: The sampling was non-probabilistic by convenience, 10 trainees were included during 
the two years of training, treating 30 patients (3 patients per trainee) during the 1st year and 
another 30 patients in the 2nd year (22 months in total). A video camera was used to record the 
procedures from 3 different angles with a time no longer than 5 minutes (2 lateral views (right 
and left) and a frontal view) in the different patients following the National Institute for 
Occupational Safety and Health (NIOSH). Video recording protocol for workstation analysis and 
risk factor assessment. Camera position was standardized for all recordings. The video recordings 
were evaluated by Rodgers muscle fatigue analysis (RMFA) and rapid upper extremity 
assessment (RULA). The endodontic act to be selected would be exclusively upper or lower 1st 
molars during the opening and ultrasonic search of the 4th canal in upper 1st molars or the 
search of the mesiocentral in lower 1st molars. The questionnaire was administered in printed 
form to all students with prior informed consent, preserving the principles of autonomy, 
beneficence, justice and non-maleficence. The measuring instrument was the standardized 
Nordic Kuorinka Musculoskeletal Symptom Perception Questionnaire. The data from the 
questionnaires were compiled in a spreadsheet program (Microsoft Excel); measures of central 
tendency and dispersion were calculated as well as tables and figures. Sociodemographic 
variables such as age, sex, course, weight, height, symptoms of musculoskeletal disorders, body 
regions affected and times of symptom onset were recorded.