X-Rays Standing x-rays are an integral part of the Sports Medicine Orthopedic knee examination. Standing x-rays are obtained at 40° of flexion which may reveal symmetrical space between the compartments or may indicate some narrowing of the normal anatomical space between the femoral condyle and tibial plateau.

Equal symmetrical wide spaces indicate a young knee whereas complete loss of joint space with bone touching bone indicates a very old x-ray of any knee. These spaces are filled with hyaline articular cartilage covering the distal femur, a meniscus, and hyaline articular cartilage of the proximal tibial plateaus.

By deduction, the narrowing seen on standing x-rays indicates loss of the hyaline articular cartilage. This polymer has components of of glucosamine, chondroitin, aminoglycosides, and polysaccharides, which can wear depending upon injury or activity level. With the thinning, roughness, fissuring, and flaps formation, the diagnosis is chondromalacia. Complete loss of the articular cartilage with exposed subchondral bone is osteoarthritis.

The rate of wear and progressive loss of the hyaline articular cartilage polymer is accelerated with impact, shear, torque, and stress which can be associated with types of job responsibilities, types of conditioning exercises, or the level of competitive sports.

With analysis of basketball, football, softball, tennis, running, and volleyball, significant forces are generated to the knee as compared to participation in cycling, lifting weights, swimming, elliptical trainers, golf, or marbles.

As our knees age age, we may have to shift to different activities.