Rib Spring Test (seated and prone) is used to determine what?

• A. To determine rib fracture
• B. To assess thoracic range of motion
• C. To evaluate diaphragmatic function
• D. To determine if a rib is out of joint

Answer: (D)

Rib spring test evaluates how freely a rib moves at its costovertebral joints, checking for rib dysfunction or subluxation. In this assessment, the clinician gently applies a small springing (anterior-posterior) impulse to the rib at the corresponding vertebral level, with the patient seated or prone, to feel the quality of the rib’s motion relative to the spine. When a rib is out of joint, the joint mechanics change, and the springing response becomes abnormal—indicating abnormal rib mobility consistent with rib subluxation or dysfunction. This is distinct from detecting a fracture, which relies on tenderness and imaging; it also doesn’t directly assess thoracic range of motion or diaphragmatic function, which require other tests.