Original Research Pectoralis minor index range of healthy 18–24-year-old students from a Kenyan public university

Eugene C. Agweyu, Joseph M. Matheri, Benita Olivier, Elzette Korkie

South African Journal of Physiotherapy | Vol 81, No 1 | a2096 | DOI: https://doi.org/10.4102/sajp.v81i1.2096 | © 2025 Eugene C. Agweyu, Joseph M. Matheri, Benita Olivier, Elzette Korkie | This work is licensed under CC Attribution 4.0
Submitted: 12 June 2024 | Published: 28 February 2025

About the author(s) Eugene C. Agweyu, Department of Rehabilitation Sciences, School of Medicine, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi Kenya Medical Training College, The Nairobi Hospital, Nairobi, Kenya
Joseph M. Matheri, Department of Rehabilitation Sciences, School of Medicine, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Benita Olivier, Centre for Healthy Living Research, Oxford Institute of Allied Health Research, School of Sport, Nutrition and Allied Health Professions, Oxford Brookes University, Oxford, United Kingdom Wits Cricket Research Hub for Science, Medicine and Rehabilitation, Department of Physiotherapy, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
Elzette Korkie, Department of Physiotherapy, School of Health Care Sciences, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa

Abstract

Background: The pectoralis minor muscle (PMM) length is critical for shoulder movement and stability, often implicated in dysfunction and pain. The pectoralis minor index (PMI) quantifies this muscle’s length relative to body dimensions. Typical PMI values range from 10.0 cm to 12.5 cm in healthy adults, with data for Kenyan populations.

Objectives: This study aimed to establish baseline PMI values among healthy 18–24-year-old university students in Kenya, examining variations by side dominance and sex to support clinical assessments.

Method: A cross-sectional descriptive study recruited 289 healthy young adults from Jomo Kenyatta University of Agriculture and Technology (JKUAT) using stratified and simple random sampling. Data were collected through a self-developed, interviewer-administered questionnaire, achieving a 93.4% response rate. PMI values were measured in three postures: supine, relaxed, and standing.

Results: In the standing relaxed position, the PMI mean was 10.6 cm on the dominant side and 11.2 cm on the non-dominant side, with significant variation indicated by a 95% confidence interval. A paired t-test revealed a significant difference between dominant and non-dominant sides (p < 0.0001).

Conclusion: Baseline PMI values for Kenyan young adults show significant differences by dominance and sex. These findings provide a foundational reference for assessing PMI in clinical settings, supporting physiotherapists and clinicians in evaluating and treating shoulder dysfunction using precise muscle length data.

Clinical implications: Establishing baseline PMI values assists physiotherapists in identifying deviations, enabling targeted interventions for shoulder dysfunction.

Keywords

pectoralis minor index; shoulder dysfunction; shoulder pain; muscle length; baseline PMI values

Sustainable Development Goal

Goal 3: Good health and well-being

Metrics Total abstract views: 404
Total article views: 355

Crossref Citations

No related citations found.