The effects of knee direction, physical activity and age on knee joint position sense

•Normative absolute error scores ranged from 2.5°-3.9°.•Knee extension and flexion error scores are significantly different when age group data were pooled.•Active participants had better knee proprioception than inactive participants.•There may be an age-related decline in knee proprioception.

BackgroundPrevious research has suggested a decline in knee proprioception with age. Furthermore, regular participation in physical activity may improve proprioceptive ability. However, there is no large scale data on uninjured populations to confirm these theories. The aim of this study was to provide normative knee joint position data (JPS) from healthy participants aged 18-82 years to evaluate the effects of age, physical activity and knee direction.MethodsA sample of 116 participants across five age groups was used. The main outcome measures were knee JPS absolute error scores into flexion and extension, Tegner activity levels and General Practitioner Physical Activity Questionnaire results.ResultsAbsolute error scores in to knee flexion were 3.6°, 3.9°, 3.5°, 3.7° and 3.1° and knee extension were 2.7°, 2.5°, 2.9°, 3.4° and 3.9° for ages 15-29, 30-44, 45-59, 60-74 and 75 years old respectively. Knee extension and flexion absolute error scores were significantly different when age group data were pooled. There was a significant effect of age and activity level on joint position sense into knee extension. Age and lower Tegner scores were also negatively correlated to joint position sense into knee extension.ConclusionsThe results provide some evidence for a decline in knee joint position sense with age. Further, active populations may have heightened static proprioception compared to inactive groups. Normative knee joint position sense data is provided and may be used by practitioners to identify patients with reduced proprioceptive ability.