The Shoulder Biomotion Laboratory is a cooperative effort under the direction of Jon Warner, MD and Guoan Li, PhD. The laboratory seeks to understand the complex motion of the human shoulder in varying states from healthy to diseased, in effort to improve treatment options. We were the first to measure the in-vivo contact locations in individuals with total shoulder arthroplasty, indicating that contact is not centered on the glenoid component. Additionally, we pioneered an inter-neural tagging technique to track nerves in three dimensions with dual plane fluoroscopy. This technique was applied to the suprascapular nerve in the shoulder.
We investigated the course of the suprascapular nerve with simulated rotator cuff muscle forces. Simulation of a massive rotator cuff and release of the transverse scapular ligament is shown in the animation (below) in purple, shows retraction of the nerve towards the spinoglenoid notch and an upward motion of the nerve at the suprascapular notch. The normal nerve course is shown in green. This retraction of the nerve may be responsible for neuropathy in many individuals with rotator cuff tearing symptoms, while releasing the ligament may help minimize pain.

We are investigating the dynamic motion of the healthy human shoulder joint with dual plane fluoroscopy. This technique was validated in a cadaver model and an animation (below) of the motion is shown. The goal of this study is to create a database of normal shoulder motion patterns from which we can compare other groups that have various pathologies, such as instability, rotator cuff tearing, and total shoulder arthroplasty.

Faculty:
PhD Candidates:
Past Fellows:
Recent Publications
Phone: 617-643-7279
Email: dmassimini@partners.org
Hours: M-F, 9am-5pm
Public Transportation Access: yes
Disabled Access: yes

Proto magazine stakes its ground on medicine's leading edge, reporting back from the frontiers of research and practice - exploring breakthroughs, dissecting controversies and opening a forum for informed debate.
Discover the largest hospital-based research program in the U.S. and how clinicians and scientists chart new terrain in biomedical research to treat and prevent human disease and bring the latest advances to patient care
Discover what makes Massachusetts General Hospital not just one of the best places to receive patient care but also one of the best places to work.