“Jamie’s Thighs” or “Ode to Joy!”
So, to start this lesson, I’ll be having ye know a few more things about muscles and bones of the thigh and the knee otherwise some of this lesson is no gonna make sense! The hip and knee joints are sites where bones move relative to each other. Skeletal muscles attach to the participating bones and span the joints; the attachment site that is fixed (doesn’t move) is the origin of a muscle and the attachment site that does move is its insertion. Next, our brains direct these muscles to contract. If muscle contraction brings the bones of the joint closer together, this is flexion (the hip joint has other movements but they don’t concern us today). If muscle contraction straightens the joint, it is extension (Photo A).
Understand that anatomists don’t use the terms upper and lower leg. For the lower limb, the region between hip and knee joints is the thigh, the region between knee and ankle joints is the leg and the foot is the remainder (Photo B). The dashed blue line in photo B represents the vertical midline plane through the body. A medial structure is closer to the midline and a lateral structure is further away from the midline! Aye, that’s the gist of it!