The influence of gait pattern on signs of knee osteoarthritis in older adults over a 5-11 year follow-up period: a case study analysis

There is evidence that joint load is a factor in the development of osteoarthritis (OA) and, while altered gait profiles have been linked with OA, it is unknown if abnormal gait is a cause or effect of the disease. While the knee's adduction moment has been implicated in the development and progression of knee OA, it is also known that shearing forces are detrimental to the health of cartilage. The purpose of this pilot study was to examine the adduction moment and gait shear forces to determine if they may lead to signs of knee OA in older adults as they age. Knee gait kinetics, standardized radiographs and a questionnaire were collected on 28 older adults (M:13) during an initial visit, and 5 to 11 years later. Radiographic score increased (knees became more osteoarthritic in 15 of 28 subjects) over time. However, gait time-distance measures remained constant in disease free participants. Two returning participants developed symptoms and radiographic evidence of knee OA. The subject with the largest adduction moment developed signs of medial OA while the subject with the smallest adduction moment developed signs of lateral OA. In addition, there was a strong correlation between the magnitudes of the adduction moment and lateral-medial shear force that needs to be investigated further. Results suggest that gait can remain stable over time in older adults. Also, the medial and lateral OA case study findings suggest that the extreme gait profiles seen in these two participants may be important in explaining cartilage breakdown and the development of OA. This longitudinal study would suggest that perhaps it is the abnormal gait pattern that leads to the development of OA, although a much larger study would be needed to confirm this finding.

Through the years: a longitudinal study of physical education teachers from a research-based preparation program

This study investigated factors that enhanced and constrained the career development of six teachers, who had graduated from the same university teacher education program, in their induction years (Woods & Earls, 1995) and again later in their career cycles. Three participants were physical education teachers (PETs), and three were former physical education teachers (FPETs). Fessler's (1985) Teacher Career Stage Model provided the theoretical framework. Data sources were: interviews with teachers and their teacher educators and direct observations of lessons. Results indicated that the PETs continued to have skill development as their primary teaching objective. The teachers maintained many of their teaching skills, and shifted between the career cycles of "competency building" and "enthusiastic and growing." All three FPETs left their physical education positions during the career frustration stage and at the time of publication were in the career exit stage.