Buttock

Description

Posterior surface anatomy of the gluteal region is presented on an adult Black male in neutral anatomical position, with the gluteus maximus forming the dominant superficial mass over the posterior pelvis and proximal femur. Superiorly, the contour relates to the iliac crest and posterior superior iliac spine, while medially the cleft overlies the sacrum and coccyx; laterally the buttock rounds toward the greater trochanter and the tensor fasciae latae region. The inferior border is defined by the gluteal fold, a skin crease that lies distal to the ischial tuberosity rather than directly over it. Both gluteus medius and minimus are implied deep and superolateral to maximus, spanning from the lateral ilium toward the greater trochanter. Clinical teaching often hinges on getting the topography right. The superolateral quadrant of the buttock is the standard landmark for intramuscular injection because it keeps the needle away from the sciatic nerve as it exits the greater sciatic foramen deep to the piriformis and passes inferior to gluteus maximus. Surface asymmetry here also matters in gait assessment: weakness or tears of gluteus medius and minimus at the greater trochanter can produce a Trendelenburg sign and lateral hip pain, often misattributed to the lumbar spine. A common stumbling block is the gluteal fold, which does not mark the true inferior limit of gluteus maximus. Use this posterior view for gross anatomy labs, kinesiology instruction on hip extension and abduction mechanics, or as a clean figure in orthopedic and sports medicine materials discussing gluteal tendinopathy, injection technique, or posterior hip surgical approaches. It also integrates well into patient education sheets where skin tone representation and accurate landmarks matter. Anatomical accuracy verified by SciePro's Medical Advisory Board.