Risk Factors Associated with Knee Pain in Male Military Personnel: A Case-Control Study

Knee pain causes the inability to perform daily activities, reduced productivity and combat readiness of the troops, and increased health care costs. The aim of this study was to investigate the risk factors related to knee pain in male military personnel.

This study was a case-control study in which 150 military personnel with chronic knee pain and 150 healthy men were assessed through simple nonprobability sampling. A three-part questionnaire (Demographic, occupational, and Clinical Information) was used with closed questions, Knee Injury and Osteoarthritis Outcome Score (KOOS), WOMAC Osteoarthritis Index, JRPD (Job-Related Physical Demands questionnaire), and HRA (Health Risk Appraisals questionnaire) and meters and scales as tools. For the people of both groups, the four mentioned questionnaires were taken in one session and the contents of both groups were analyzed and reviewed.

There was no statistically significant difference between the baseline demographic results (age, height, weight, work experience) in the two groups. Among the factors studied, there was a positive significant relationship between knee pain and hard job category variables (P=0.010), prolonged work experience (P=0.001), heavy and continuous physical activity (P=0.025), weakness in quadriceps (P=0.001), variables of exercise level (P=0.002), previous history of knee pain (P=0.003), and the existence of bad knee posture during activity (P=0.003), working in the position of bending the knees for a long time (P=0.001), working in the position of two knees for a long time (P=0.003), working in long-term quadruple position (P=0.003), and working in a long-term squatting position (P=0.002). Also, BMI (P=0.015), level of education (P=0.001), smoking (P=0.015), deformity in the lower limbs and knees (P=0.003), swelling in the knee (P=0.003),cryptation in the knee (P=0.002), dryness and limited mobility in the knee (P=0.005), and shortening of the hamstrings muscles (P=0.003) showed a significant negative correlation with knee pain.

It seems possible to reduce the amount of these factors by preventing knee pain or expanding them, and improving the level of military personnel efficiency.