During a routine sports physical, a 12-year-old shows asymmetry of the posterior chest wall on forward bending. This finding is most consistent with which condition?

• A. Spondylolysis
• B. Spondylolisthesis
• C. Scoliosis
• D. Herniated disc

Answer: (C)

Asymmetry of the posterior chest wall when bending forward points to scoliosis, a lateral curvature of the spine with vertebral rotation that produces a rib hump. In the forward bend test, the rotated vertebrae cause the ribs on the convex side to protrude, making one side of the back appear higher or more prominent. In a 12-year-old, this pattern is most consistent with adolescent idiopathic scoliosis, a common finding during routine youth screening. The other conditions don’t typically cause a rib hump on forward bending: a stress fracture of the pars interarticularis can cause back pain without rib prominence; spondylolisthesis involves forward slippage and often a palpable spinal step-off or neuro symptoms; a herniated disc usually presents with back pain and radicular symptoms rather than chest wall asymmetry.