CT-based and morphological comparison of glenoid inclination and version angles and mineralisation distribution in human body donors

Figures

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  Fig. 1. Representative images of osteoarthritis grades I, II, III and IV in dissected glenoids

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  Fig. 2. Representative images of osteoarthritis grades I, II, III and IV in dissected humeral heads. (I) N points to the notch in the humeral head formed by the tendon of the long head of the biceps used as a reference for CT-OAM and morphological inspections

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  Fig. 3. 2D-CT images of 3D-CT reconstructions of the articular surfaces of a left shoulder. A Height and width of the glenoid measured as described [35]: a line drawn from the most cranial (A) to the most caudal point (B) of the glenoid cavity, and another line from the most ventral (C) to the most dorsal point (D) of the glenoid rim. B Height and width of the humeral head measured using established landmarks [26]: the greater tubercle as reference to place the uppermost point (A) at the edge of the smooth articular surface and a perpendicular line was drawn to the lowest (B) point. C The depth of the humeral head measured using established landmarks [26]: the lesser tubercle as reference for the most anterior point (F), from this, a perpendicular line was drawn to the most posterior point (E) of the smooth articular surface. D The inclination angle α was determined in the coronal plane using reference points (green) as described [7, 35]: a line was drawn through the root of the scapular spine to the midpoint of the glenoid cavity, and a second line through the most cranial and caudal points (see A, reference points A and B) of the glenoid rim. Angle γ was measured between the axes of…

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  Fig. 4. Representative CT-OAM images showing mineral distribution of (A) glenoid, and (B) humeral head. CT-OAM false colour-encoded (black > red > orange > yellow > bright green > dark green > blue > violet, see: [57]) and superimposed on the identical 3-D-reconstructed joint. N points (A) to the most superior point of the glenoid, and (B) to notch in the humeral head formed by the tendon of the long head of biceps. (C, D) A grid was superimposed over the CT-OAM and morphology images to separate the articular surface in quadrants of glenoid (C) and humeral head (D) similar to previous work [57, 58]

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  Fig. 5. Glenoid and humeral head specimens of a 69 years old female. Inclination: R 10.7°, L 15.9°; retroversion: R -7.6, L − 9°. Note homogenous mineralisation distribution with anterior maxima of the glenoid (D), mirrored by intact cartilage (B) and some spots on the glenoid rim (C) with some cartilage erosions (A). Monocentric mineralisation pattern of the humeral head (G, H) is accompanied by healthy cartilage (E, F). Note pronounced (L > R) chondral print

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  Fig. 6. Glenoid and humeral head specimens of a 74 years old male with pronounced signs of osteoarthritis (A,B). On the right (R), inclination (7.1°) and retroversion (− 2.7°) with homogenously distributed mineralisation and a moderate caudal shift (C). On the left (L), inclination (10.7°) and retroversion (− 9.5°) combined with antero-caudal enhanced mineralisation (D). Both humeral heads with pronounced osteoarthritic defects grade IV in the dissected specimens (E, F), without (G) or only partial (H) congruency to mineralisation distribution

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  Fig. 7. Mineralisation distribution in glenoids with inclination angles < 10°. A-D 73 years old male (inclination: R 7.8°, L 3.3°; retroversion: R -6.9°, L -6.7°). C,D On both sides, in addition to anterior mineralisation, density maxima in cranial and dorsal quadrants corresponding to cartilage defects (A,B). Cartilage thinning in the anterior, more caudal quadrants (A,B) mirrored by CT-OAM (C, D). Some spots along the glenoid rim, probably osteophytes. E-H 72 years old male (inclination: R 7.6°, L 2.9°; retroversion R -1.7°, L − 0.4°). In the left shoulder, note higher mineralisation in cranial quadrants (H) and cartilage lesion (F). Some spots along the glenoid rim probably osteophytes

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  Fig. 8. Search for optimal ranges of glenoid angles. Inclination (A, B) and ante−/retroversion (C, D) angles (°, Y-axis), covering (grey area) a maximum of physiological mineralisation distribution patterns (x-axis), i.e. predominantly central (A,B), ventral > dorsal (C,D), and a minimum of different patterns. A,B Grey area covers superior inclination ≤10°, green areas expanded margins ≤15° in selected cases. C,D Grey area covers ante−/retroversion angles from − 8° to − 4°, green areas expanded margins ±1° in selected cases. R right, L left shoulders