Lateral rib expansion is the lower ribs widening sideways and back on the inhale, a sign the diaphragm is working.
Hands on the sides of the lower ribs feel them move out rather than the shoulders hiking. In 📝Breathwork that movement is the cue that 📝diaphragmatic breathing is available. It is a finding, not a diagnosis of a stiff ribcage as a medical fact, and not a claim to treat the lungs. A 📝rib flare that lifts the front without the sides is a different pattern.
Clients feel width instead of a high chest. If the sides will not move, the inhale is smaller, slower, and nasal — not forced. Chest pain or unexplained shortness of breath is a referral.