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Updated: Jul 7, 2026
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Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Scapular inclination and glenohumeral joint stability: a cadaveric study
Kazuma Kikuchi1, Eiji Itoi, Nobuyuki Yamamoto
1Division of Orthopedic Surgery, Department of Neuro and Locomotor Science, Akita University School of Medicine, Akita, Japan.
Summary
Glenoid inclination significantly impacts shoulder stability. Anterior tilts improve posterior and inferior stability, while posterior tilts can decrease anterior and posterior stability, affecting multidirectional instability management.
Area of Science:
- Orthopedic Surgery
- Biomechanics
- Human Anatomy
Background:
- Multidirectional instability in shoulders involves increased humeral head translation.
- Contributing factors include increased retroversion, hypoplastic glenoid rim, and decreased scapular abduction.
- Glenoid inclination's role in joint stability requires clarification.
Purpose of the Study:
- To investigate the relationship between glenoid inclination and glenohumeral joint stability.
- To quantify the effect of varying glenoid tilt angles on shoulder stability.
Main Methods:
- Nine fresh-frozen cadaveric shoulders were analyzed.
- A 50-N compressive load was applied.
- Translation forces were measured at various tilt angles (0-20 degrees) and directions (3, 6, 9, 12 o'clock).
Main Results:
- A tilt >5 degrees in the 3-o'clock direction decreased stability in that direction.
- A tilt >15 degrees in the 9-o'clock direction decreased stability, while a 3-o'clock tilt >5 degrees increased it.
- A 6-o'clock tilt >10 degrees increased stability in that direction.
Conclusions:
- Posterior and inferior stability increase with anterior glenoid tilt (>5 and >10 degrees, respectively).
- Anterior and posterior stability decrease with anterior tilt (>5 degrees) and posterior tilt (>15 degrees), respectively.
- Glenoid inclination is a critical factor influencing glenohumeral joint stability.
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