NBCE Practice Test Prep – National Board of Chiropractic Examiners Study Guide & Practice Exam

The enlargement of cartilage at the costochondral junctions is primarily associated with Rickets. This condition is commonly seen in children due to a deficiency in vitamin D, calcium, or phosphate, leading to poor mineralization of the growing bones. As a result, the costochondral junctions, where the ribs meet the cartilage, can become markedly enlarged, causing the characteristic "rachitic rosary" appearance along the chest wall. This distinct presentation helps in diagnosing Rickets, as it is markedly different from conditions like Marfan syndrome, which affects connective tissue and does not specifically lead to such cartilaginous enlargements, or Achondroplasia, which primarily impacts endochondral ossification patterns leading to disproportionate growth without localized enlargement of the costochondral junctions. Paget's disease, primarily affecting older adults, involves abnormal bone remodeling but does not typically present with cartilaginous enlargement at the costochondral junctions like Rickets does.