Gluteal tendinopathy: a pain in the butt

No matter how good the general condition of an athlete, the fact is that there are times when the biomechanical demands of his or her sport exceeds the ability to control motion and the stability throughout the kinetic chain of the muscles and joints used to execute that movement. For example, consider a javelin thrower; when the athlete releases the javelin with explosive force, the muscules of the lead hip need to resist considerable forces in all three planes of motion. If any weakness exists in any plane of movement, the kinetic chain can be destabilized, and injury may be the result.

One problematic condition for athletes that can arise from this and similar scenarios is something called ‘gluteal tendinopathy(either gluteus medius or gluteus minimum). The combination of overuse and underlying weakness of the gluteus medius and minimis –two key buttock muscles - can cause strain, tearing, or degeneration of these muscles or their respective tendons, inducing tendinopathy (tendon inflammation) in the athlete.

Understanding hip and buttock anatomy

A schematic view of gluteus medius and minimus can be seen in figure 1 below. The gluteus medius muscle originates iliac crest region of the pelvis and crosses over the greater trochanter (the bony projection at the top of the femur). Gluteus medius is a primary hip abductor, which means it moves the leg outwards and away from the center line of the body. Its frontal fibres rotate the hip inwards, while the rear fibers assist in outwards rotation. In weight bearing positions, these muscles help keep the pelvis from dropping to one side.

Gluteus minmus meanwhile is a fan-shaped muscle underneath the gluteus medius muscle, and which stretches from the same area of the pelvis, but attaches instead to the outside of the trochanter. Gluteus minimus (in association with other muscles) primarily abducts the hip when the hip is in extension (ie the thigh is lined up with the upper body), and another key function of this muscle is to help stabilise the ball-shaped head of the femur in the hip socket of the pelvis (acetabulum) when an individual is walking.

Figure 1: A schematic representation of gluteus medius and minimus