Development of an intervention to manage knee osteoarthritis risk and symptoms following anterior cruciate ligament injury.

Introduction: Anterior cruciate ligament (ACL) injury is a risk factor for developing knee osteoarthritis (OA). We developed an intervention to support people manage risk factors for OA.

Methods: We conducted one-on-one interviews with 20 individuals with OA symptoms 6-15 years post ACL injury and used a nominal group process during a workshop with 40 patients and healthcare professionals (HCPs) to elicit information on the intervention content and delivery characteristics (timing, HCPs, and methods).

Limiting the Risk of Osteoarthritis After Anterior Cruciate Ligament Injury: Are Health Care Providers Missing the Opportunity to Intervene?

Objective: To understand what sports orthopedic surgeons (OS), primary care physicians (PCPs) with sports medicine training, and physical therapists (PTs) managing nonelite athletes with anterior cruciate ligament (ACL) injury tell their patients about their osteoarthritis (OA) risk.

Methods: An electronic survey was distributed by the Canadian Academy of Sport and Exercise Medicine (PCPs, OS), the Sports and Orthopedic Divisions of the Canadian Physiotherapy Association (PTs), and to OS identified through the Royal College of Physicians and Surgeons and the Canadian Orthopaedic Association. The survey included 4 sections: demographics, factors discussed, timing of discussions, and discussion of risk factors and their management.

In vivo increase of the human lens equatorial diameter during accommodation.

The movement of the human lens equator during accommodation was examined in vivo. High-resolution ultrasound images of the lens equator were obtained from young human subjects whose amplitude of accommodation was controlled with 1% tropicamide and 2% pilocarpine. To avoid errors that otherwise arise from eye rotation or other movement, the cornea and sclera were used as positional references in comparative studies of the video images obtained from the unaccommodated and accommodated states.

The effect of gravity on the amplitude of accommodation.

We measured the amplitude of accommodation in the supine and prone positions of young subjects. We found that gravity does not influence accommodative amplitude. These findings support Schachar's zonular function and accommodative hypotheses that the lens is stable and under tension during accommodation.

A physical model demonstrating Schachar's hypothesis of accommodation.

Schachar's hypothesis of accommodation states that there is increased zonular tension during accommodation and the observed in vivo changes in lenticular curvature that occur during accommodation are the result of zonular forces. To demonstrate that there can be steepening of the central curvature of the lens with increased zonular tension, profile photographs of an equatorially unstretched and stretched gelatin-filled balloon and profile photographs from the literature of an unstretched and equatorially stretched human lens were digitized. Their radii of curvature were determined.