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. 2021 Jul;2(7):552-561.
doi: 10.1302/2633-1462.27.BJO-2021-0081.R1.

CT-based volumetric assessment of rotator cuff muscle in shoulder arthroplasty preoperative planning

Jean-David Werthel  1   2 , François Boux de Casson  3   4 , Valérie Burdin  2 , George S Athwal  5 , Luc Favard  6 , Jean Chaoui  3   4   7   8 , Gilles Walch  9   10
Affiliations

CT-based volumetric assessment of rotator cuff muscle in shoulder arthroplasty preoperative planning

Jean-David Werthel et al. Bone Jt Open. 2021 Jul.

Abstract

Aims: The aim of this study was to describe a quantitative 3D CT method to measure rotator cuff muscle volume, atrophy, and balance in healthy controls and in three pathological shoulder cohorts.

Methods: In all, 102 CT scans were included in the analysis: 46 healthy, 21 cuff tear arthropathy (CTA), 18 irreparable rotator cuff tear (IRCT), and 17 primary osteoarthritis (OA). The four rotator cuff muscles were manually segmented and their volume, including intramuscular fat, was calculated. The normalized volume (NV) of each muscle was calculated by dividing muscle volume to the patient's scapular bone volume. Muscle volume and percentage of muscle atrophy were compared between muscles and between cohorts.

Results: Rotator cuff muscle volume was significantly decreased in patients with OA, CTA, and IRCT compared to healthy patients (p < 0.0001). Atrophy was comparable for all muscles between CTA, IRCT, and OA patients, except for the supraspinatus, which was significantly more atrophied in CTA and IRCT (p = 0.002). In healthy shoulders, the anterior cuff represented 45% of the entire cuff, while the posterior cuff represented 40%. A similar partition between anterior and posterior cuff was also found in both CTA and IRCT patients. However, in OA patients, the relative volume of the anterior (42%) and posterior cuff (45%) were similar.

Conclusion: This study shows that rotator cuff muscle volume is significantly decreased in patients with OA, CTA, or IRCT compared to healthy patients, but that only minimal differences can be observed between the different pathological groups. This suggests that the influence of rotator cuff muscle volume and atrophy (including intramuscular fat) as an independent factor of outcome may be overestimated. Cite this article: Bone Jt Open 2021;2(7):552-561.

Keywords: 3D CT scan; atrophy; fatty infiltration; muscle volume; occupation ratio; rotator cuff muscle; shoulder arthroplasty; tangent sign; volumetric analysis.

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Conflict of interest statement

ICMJE COI statement: J-D. Werthel receives royalties for shoulder prosthesis design from FH Orthopedics, which is related to this work. L. Favard, G. Walch, and G. Athwal receive royalties for shoulder prosthesis design from Wright Medical, which is also related to this article. F. Boux de Casson is Wright Medical employee, and J. Chaoui owns stocks and stock options from Wright Medical, both of which are unrelated.

Open access funding

Ramsay Générale de Santé, Hôpital Privé Jean Mermoz Lyon, France.

Figures

Fig. 1
Fig. 1
Sagittal view of a right shoulder in a cuff tear arthropathy patient with severe fatty infiltration of the supraspinatus, infraspinatus and teres minor. The contours of the different muscles and their intramuscular fat can be seen. This example shows the difficulty to define precisely the contour of the presumed supraspinatus fossa.
Fig. 2
Fig. 2
Example of rotator cuff muscle segmentation on a sagittal view from the soft tissue DICOM (Digital Imaging and Communications in Medicine) series. Sagittal view of a right shoulder in a cuff tear arthropathy patient.
Fig. 3
Fig. 3
Example of rotator cuff muscle segmentation on a sagittal view from the soft tissue DICOM (Digital Imaging and Communications in Medicine) series: the threshold draw tool in the editor module of the Slicer version 4.10.0 software (Slicer Community, USA) is used to draw a line along the contour of the supraspinatus.
Fig. 4
Fig. 4
Example of rotator cuff muscle segmentation on a sagittal view from the soft tissue DICOM (Digital Imaging and Communications in Medicine) series: a preset range of muscle tissue is used to select specifically muscle tissue.
Fig. 5
Fig. 5
Example of rotator cuff muscle segmentation on a sagittal view from the soft tissue DICOM (Digital Imaging and Communications in Medicine) series: a smoothing tool is then used to include the intramuscular fat within the borders of the supraspinatus muscle tissue.
Fig. 6
Fig. 6
Example of rotator cuff muscle segmentation on a sagittal view from the soft tissue DICOM (Digital Imaging and Communications in Medicine) series: the operation described in Figure 4 and Figure is repeated for each of the rotator cuff muscle and their volume including intramuscular fat can then be included.
Fig. 7
Fig. 7
Example of rotator cuff muscle segmentation on a sagittal view from the soft tissue DICOM (Digital Imaging and Communications in Medicine) series: muscle tissue and intramuscular fat are then separated using the threshold tool.
Fig. 8
Fig. 8
Intramuscular fat, extra-muscular fat, and muscle size on the sagittal view of a healthy patient.
Fig. 9
Fig. 9
Intramuscular fat, extra-muscular fat, and muscle size on the sagittal view of a patient with a cuff tear arthropathy.
See this image and copyright information in PMC

References

    1. Iannotti JP, Walker K, Rodriguez E, Patterson TE, Jun BJ, Ricchetti ET. Accuracy of 3-dimensional planning, implant templating, and patient-specific instrumentation in anatomic total shoulder arthroplasty. J Bone Joint Surg Am. 2019;101-A(5):446–457. - PubMed
    1. Nyffeler RW, Werner CML, Gerber C. Biomechanical relevance of glenoid component positioning in the reverse Delta III total shoulder prosthesis. J Shoulder Elbow Surg. 2005;14(5):524–528. - PubMed
    1. Yongpravat C, Kim HM, Gardner TR, Bigliani LU, Levine WN, Ahmad CS. Glenoid implant orientation and cement failure in total shoulder arthroplasty: A finite element analysis. J Shoulder Elbow Surg. 2013;22(7):940–947. - PubMed
    1. Gladstone JN, Bishop JY, IK L, Flatow EL. Fatty infiltration and atrophy of the rotator cuff do not improve after rotator cuff repair and correlate with poor functional outcome. Am J Sports Med. 2007;35. - PubMed
    1. Goutallier D, Postel JM, Bernageau J, Lavau L, Voisin MC. Fatty muscle degeneration in cuff ruptures. Pre- and postoperative evaluation by CT scan. Clin Orthop Relat Res. 1994;304:78–83. - PubMed