Bone mineralization changes of the glenoid in shoulders
with symptomatic rotator cuff tear
Received: 11 December 2017 /Accepted: 28 May 2018
SICOT aisbl 2018
Purpose Computed tomography osteoabsorptiometry (CTO) is a method to analyze the stress distribution in joints by measuring
the subchondral bone density. The purpose of this study was to evaluate the bone mineralization changes of the glenoid in
shoulders with rotator cuff tears by CTO and to evaluate whether rotator cuff tears are associated with stress changes in the glenoid.
Methods In total, 32 patients, who were diagnosed with unilateral rotator cuff tears and underwent arthroscopic rotator cuff
repair, were enrolled in this study. They underwent CT scanning of both shoulders pre-operatively and the glenoid was evaluated
using CTO. Hounsfield units (HU) in seven areas of the glenoid were compared between the affected and unaffected sides.
Results The central area of the glenoid on the affected side had significantly lower HU than on the unaffected side among all
patients. Focusing on the rotator cuff tear size and the subscapularis tendon, only patients with larger cuff tears or with
subscapularis tendon tears showed significantly lower HU in the central area of the affected side.
Conclusions This study showed a decrease in bone mineralization density in the central glenoid in shoulders with rotator cuff tear.
This change was observed in the case of larger cuff tears and subscapularis tendon tears. Our results help clarify the changes in
stress distribution in the shoulder joint caused by symptomatic rotator cuff tears.
Keywords Computed tomography osteoabsorptiometry
Rotator cuff tear
Subchondral bone mineralization change
Rotator cuff muscles play a crucial role in shoulder function.
They generate the torque for humerus rotation in the glenoid
cavity. Moreover, they produce a compressive force across the
glenohumeral joint to help centralize the humeral head on the
glenoid during shoulder motion. In particular, rotator cuff
transverse force couple which is composed of the balance
between the subscapularis muscle and the infraspinatus
and teres minor muscles is a critical component of normal
biomechanics and function of the shoulder joint [1–3]. If
the rotator cuff is torn, it may lead to abnormal joint kine-
matics, causing pain and loss of shoulder function [1, 4, 5].
Although the rotator cuff tears are a common pathology,
especially in elderly people, the level of pain experienced
does not necessarily correlate with the severity of the rota-
tor cuff tears : some patients with small rotator cuff tears
complain of severely painful dysfunction, while some peo-
tator cuff tears. It is difficult to evaluate the biomechanical
changes in patients with symptomatic rotator cuff tears,
because most of the biomechanical experiments are simu-
lated studies involving the use of cadavers [1, 4]orcom-
puted simulation . In the clinical setting, it is more im-
portant to understand the biomechanical changes induced
by symptomatic rotator cuff tears.
* Yohei Harada
Department of Orthopaedic Surgery, Hiroshima City Hiroshima
Citizens Hospital, 7-33 Motomachi, Hiroshima, Naka-ku, Japan
Department of Orthopaedic Surgery, Graduate School of Biomedical
and Health Sciences, Hiroshima University, 1-2-3 Kasumi,
Hiroshima, Minami-ku, Japan
Department of Clinical Radiology, Hiroshima University Hospital,
1-2-3 Kasumi, Hiroshima, Minami-ku, Japan
Department of Orthopaedic Surgery, Hiroshima Prefectural Hospital,
1-5-54, Ujinakanda, Hiroshima, Minami-ku, Japan
Hiroshima University, 1-3-2 Kagamiyama, Higashi-Hiroshima
City, Hiroshima, Japan