Empa’s 4D X-Ray Breakthrough Reveals Shoulder Instabilities with Sub-Millimeter Precision

Empa’s 4D X-Ray Breakthrough Reveals Shoulder Instabilities with Sub-Millimeter Precision

(IN BRIEF) Empa has introduced a novel 4D X-ray diagnostic that combines synchronized biplanar X-ray videos with CT-derived 3D bone models to quantify shoulder joint motion with 0.1–0.5 mm precision. This approach uncovers instabilities invisible to static imaging or skin-marker systems, guiding optimal treatment decisions between physiotherapy and surgery. A follow-up study with Inselspital will evaluate changes in stability after muscle strengthening, and future developments aim for radiation-free, biomechanics-driven clinical tools.

(PRESS RELEASE) DÜBENDORF, 8-Jul-2025 — /EuropaWire/ — Empa researcher Dr. Ameet Aiyangar has pioneered a breakthrough four-dimensional X-ray technique that captures shoulder joint motion with sub-millimeter accuracy, offering the first dynamic 3D diagnostic tool for detecting instabilities that manifest only during movement. By synchronizing high-resolution biplanar X-ray videos with patient-specific 3D bone models reconstructed from CT scans, the system quantitatively maps the shoulder’s complex rolling and sliding motions to within 0.1–0.5 mm—far surpassing the 20–40 mm errors of conventional optical tracking.

Developed in collaboration with Bern’s sitem-insel Translational Medicine Institute and Inselspital, the method records patients performing targeted shoulder maneuvers under a dual-angle radiography setup. Proprietary optimization software then fuses the dynamic X-ray footage and anatomical models to reveal precise kinematics, enabling clinicians to distinguish which instabilities require rehabilitation versus surgical intervention. “This innovation fills a critical gap: static MRI or CT can’t show what happens when the shoulder ‘slips’ in real life,” explains Dr. Aiyangar. “With 4D analysis, we can tailor treatments—avoiding unnecessary operations or ensuring timely surgery—based on objective movement data.”

Building on this success, Empa and Inselspital will recruit 40 patients with untreated shoulder laxity for a prospective study assessing how targeted muscle strengthening alters joint stability. Future work aims to integrate musculoskeletal force modeling—accounting for muscle loads and joint stresses—to ultimately deliver a radiation-free, patient-specific dynamic diagnostic in routine clinical practice.

Media Contacts:

Prof. Dr. Ameet Aiyangar
Mechanical Systems Engineering
Phone +41 58 765 4508
ameet.aiyangar@empa.ch

Manuel Martin
Communications
Phone +41 58 765 4454
redaktion@empa.ch

SOURCE: EMPA