Mensa-Bonsu A. Ellen¹, Addai K. Frederick²,Adutwum-Ofosu Kevin², Acquah A. Augustine³, Ashigbi Y. K. Evans¹

¹ Department of Physiotherapy and Rehabilitation Sciences, School of Allied Health Sciences, University of Health and Allied Health Sciences, Ho, Ghana.

² Department of Anatomy, College of Health Sciences, University of Ghana, Legon, Accra, Ghana.

³ Department of Physiotherapy, College of Health Sciences, University of Ghana, Legon, Accra, Ghana.

Corresponding author:

E-mail: emensa-bonsu@uhas.edu.gh

Background and purpose: Students spend about 6-8 hours in the classroom daily with majority of this time in a sitting position. Prolonged and wrong sitting posture are known risk factors for musculoskeletal disorders such as back pain, neck pain, and leg pain. The use of appropriate furniture provides comfort, ensures good posture, and reduces the risk of back pain. This study seeks to determine the level of match or mismatch between gender, anthropometry, and classroom furniture dimensions in Junior High School students.

Relevance: To inform manufacturers on the need to utilize anthropometry of students when producing furniture for them in order to avoid future development of musculoskeletal disorders.

Participants: Three hundred and twenty one (321) Junior High School students (177 females; mean age 14.75±1.36 years and 144 males; mean age of 14.81±1.34 years) aged 12-19 years from 5 public schools in the Ho municipality of the Volta Region of Ghana were recruited via whole population sampling.

Methods: A cross-sectional study was conducted. Eighteen Static anthropometric variables height, weight, hip circumference, waist circumference, mid upper arm circumference, shoulder-elbow length, forearm-hand length, shoulder height, elbow height, buttock-knee length, buttock-popliteal length, knee height, popliteal height, elbow-elbow breadth, shoulder breadth, hip width, subscapular height, and one thigh thickness and 9 furniture dimensions namely seat height, seat depth, seat width, upper edge of backrest, desk height, underneath desk height, seat to desk clearance, seat to desk height and footrest were measured.

Analysis: Data entry, cleaning and analysis were performed using Microsoft Excel 2007. Standard match/mismatch equations were used to determine the level of ergonometric appropriateness of furniture.

Results: Seat height showed high mismatch (91%, 99%, 63% and 78%) for schools 2, 3, 4 and 5 respectively. Female students recorded the highest mismatch percentages (95%, 100%, 88.89% and 90.28%) compared to their male counterparts (85.71%, 97.50%, 21.43% and 60.38%) in schools 2, 3, 4 and 5 respectively. The seat width was appropriate for students in all five schools. Seat depth showed low mismatch for students in all five schools. Seat to desk height produced high mismatch for 100% of students in schools 2, 4 and 5. Upper edge of backrest was appropriate for all students in school 1. Seat to desk clearance showed 100% match for schools 1, 2 and 5. There was however a mismatch for 100% and 71% of students in schools 3 and 4 respectively.

Conclusions: Good ergonometry requires popliteal height to be higher than seat height. In this study, seat height was high (High Mismatch) for students in Schools 2, 3, 4, and 5. Affected students’ feet may not rest on the floor, blood vessels and nerves in the popliteal fossa may be compressed by the front edge of the seat. This may reduce circulation in the lower limbs causing pain, discomfort, poor posture, increased spinal load and hypertrophy of shoulder muscles.

Implications: To protect students from developing musculoskeletal disorders in future, furniture manufacturers need to provide varying furniture sizes to permit appropriate matching for all students.

Keywords: Ergonomics, Occupational health and Safety, Musculoskeletal Disorders

Funding source acknowledgement: Not applicable

Ethical Clearance: Ethical clearance was obtained from the University of Ghana College of Health Sciences Ethical and Protocol Review Committee (EPRC) with Protocol Identification Number: CHS-Et/M.4-5.3/2020-2021. Approval to conduct the study was also sought from Ho Municipal Education Office and Head teachers of selected schools. Consent and assent forms were given to guardians and students respectively to recruit participants in the study.