Movement Science II – Hip (all correct solutions)

What percentages do the ischium, ilium, and pubis contribute to the formation of the acetabulum? correct answers 1/5 pubis, 2/5 ilium, 2/5 ischium What shape is the articular cartilage of the acetabulum? What is the advantage of this shape? correct answers Horseshoe-shaped, lunate. It allows the contact forces to be distributed. What structure spans the acetabular notch? correct answers Transverse acetabular ligament. True or False: The femoral head does not contact the deepest part of the acetabulum (aka acetabular fossa). correct answers True. The acetabular fossa in non-articular. The fibrocartilaginous structure that is found on the periphery of the acetabulum is called the: correct answers Acetabular labrum. What is the normal orientation of the acetabulum with respect to planes of the body? correct answers Frontal plane: laterally inclined 50° Transverse plane: anteverted 20° Sagittal plane: anteriorly tilted 20° What is acetabular dysplasia? What are some general consequences? correct answers Inadequate/reduced coverage of the femoral head by the acetabulum = acetabulum shallow. Instability, disproportionate loading on superior rim, mechanical abnormality. When the femoral head is excessively covered by the acetabulum it is called: correct answers Coxa profunda, acetabular protrusio. Results in limited ROM, internal impingement. The name of acetabular depth measurement (angle created from edge of acetabulum and line center of femoral head) is: What is the normal angle, and what constitutes over- or under-coverage? correct answers Center edge angle of Wiberg. Normal - greater than 25° Possible dysplasia - 16-25° Definite dysplasia - less than 16° Overcoverage - greater than 40° What are 5 functions of the acetabular labrum? correct answers 1. Deepens socket. 2. Increases concavity with its triangular shape. 3. Acts as seal, creates negative intra-articular pressure. 4. Decreases force transmitted to articular cartilage. 5. Provides proprioceptive feedback (can cause pain, contains nerve endings). True or False: The transverse acetabular ligament is a load-bearing structure. correct answers False. Its function is not to distribute force. It protects blood vessels that supply the femoral head.