All of the following statements about the hip joint are correct EXCEPT:

## Analysis of Hip Joint Anatomy ### Correct Statements **Key Point:** The hip joint is indeed a synovial ball-and-socket joint (multiaxial) formed between the femoral head and acetabulum, allowing flexion, extension, abduction, adduction, medial and lateral rotation, and circumduction. **High-Yield:** The acetabular labrum is a fibrocartilaginous ring attached to the rim of the acetabulum. It deepens the socket by approximately 20% and increases the surface area for articulation, improving joint stability and load distribution. **Clinical Pearl:** The iliofemoral ligament (Y-shaped ligament of Bigelow) is indeed the strongest ligament in the human body. It reinforces the anterior joint capsule and prevents excessive hip extension and external rotation. ### The Incorrect Statement The ligamentum teres (round ligament) does NOT carry the medial and lateral circumflex femoral arteries. Instead: | Vessel | Source | Course | |--------|--------|--------| | **Medial circumflex femoral artery** | Profunda femoris artery | Passes medial to femur, supplies femoral head via lateral epiphyseal branches | | **Lateral circumflex femoral artery** | Profunda femoris artery | Passes lateral to femur, supplies femoral head via medial epiphyseal branches | | **Ligamentum teres artery** | Obturator artery (small, inconstant) | Runs within ligamentum teres; supplies only a small portion of femoral head in children | **Mnemonic:** **LCFA** = Lateral Circumflex Femoral Artery supplies the **Medial** (lateral epiphyseal) head; **MCFA** = Medial Circumflex Femoral Artery supplies the **Lateral** (medial epiphyseal) head. The ligamentum teres artery is negligible in adults. **High-Yield:** The medial and lateral circumflex femoral arteries are the primary blood supply to the femoral head in adults. Disruption of these vessels (especially in femoral neck fractures) leads to avascular necrosis of the femoral head.