This research study is being conducted at the Medical University of South Carolina (MUSC). The purpose of this study is to better understand injury to the small nerves that run between the ribs following rib fractures, and to learn what normal sensation and muscle appearance of the abdominal wall (muscles of the stomach area) look like in healthy adults. This information will help doctors better recognize and diagnose nerve injuries in patients who have had trauma, surgery, or other conditions affecting the abdominal wall.

Researchers will use simple sensory testing of the skin of the abdomen and ultrasound imaging to measure abdominal muscle structure. The sensory testing, called two-point discrimination, measures how well participants can tell the difference between two nearby points touching the skin using a small measuring tool that lightly touches the skin of the abdomen. Ultrasound imaging uses sound waves to create images of the inside of the body and will be used to measure the thickness and appearance of the abdominal muscles. This study includes two groups of participants: healthy volunteers and individuals with rib fractures.

Healthy volunteers will complete a single study visit lasting about 45 minutes, during which participants will undergo sensory testing, ultrasound imaging, and a short questionnaire. Participants with rib fractures will complete research procedures during their scheduled clinical follow-up visits, which include a baseline visit and three follow-up visits over approximately 12 weeks; research activities, including ultrasound imaging, will add about 30 minutes to each visit.