Table 2.
Morphometric characteristics of the anatomical variations of the clavicular part of the pectoralis major muscle (PM).
| The width of the origin of the clavicular part of PM [mm] | ||||||
|---|---|---|---|---|---|---|
| Minimal value | Maximal value | Mean | Median | Standard deviation | ||
|
| ||||||
| Typical variants of PM | Male cadavers | 70 | 105 | 87 | 83 | 13 |
| Female cadavers | 63 | 88 | 76 | 77 | 9 | |
| Total | 63 | 105 | 82 | 81 | 12 | |
|
| ||||||
| Variants with separated clavicular part | Male cadavers | 47 | 92 | 69 | 70 | 18 |
| Female cadavers | 59 | 84 | 72 | 73 | 10 | |
| Total | 47 | 92 | 66 | 68 | 17 | |
|
| ||||||
| Variants with fusion between PM and deltoid muscle | Observed only in two male cadavers | 99 | 115 | 106 | 105 | 7 |
|
| ||||||
| Atrophy of the clavicular part of PM | Observed only in one female cadaver | 32 | 38 | 35 | 35 | 4 |
|
| ||||||
| Percentage of total length of the clavicle covered by the origin of the clavicular part of PM [%] | ||||||
|
| ||||||
| Minimal value | Maximal value | Mean | Median | Standard deviation | ||
|
| ||||||
| Typical variants of PM | Male cadavers | 47.2 | 68.7 | 56.9 | 52.6 | 9.4 |
| Female cadavers | 42.5 | 79.2 | 57.1 | 50.9 | 13.1 | |
| Total | 42.5 | 79.2 | 57 | 51 | 11 | |
|
| ||||||
| Variants with separated clavicular part | Male cadavers | 31.9 | 56.4 | 40.4 | 42.5 | 9.9 |
| Female cadavers | 40.1 | 50.9 | 46.2 | 47,2 | 3.8 | |
| Total | 31.9 | 56.4 | 43.5 | 43.6 | 7.6 | |
|
| ||||||
| Variants with fusion between PM and deltoid muscle | Observed only in two male cadavers | 60.1 | 83.3 | 71.5 | 70.4 | 12.6 |
|
| ||||||
| Atrophy of the clavicular part of PM | Observed only in one female cadaver | 22.5 | 26 | 24.2 | 24.2 | 2.5 |
|
| ||||||
| Asymmetry between right and left side in percentage of total length of the clavicle covered by the origin of the clavicular part of PM [%] | ||||||
|
| ||||||
| Minimal value | Maximal value | Mean | Median | Standard deviation | ||
|
| ||||||
| Typical variants of PM | Male cadavers | 0.9 | 23.2 | 8.4 | 6.7 | 7.8 |
| Female cadavers | 4.3 | 11.2 | 7.4 | 7.2 | 2.6 | |
| Total | 0.9 | 23.2 | 7.9 | 7.2 | 5.8 | |
|
| ||||||
| Variants with separated clavicular part | Male cadavers | 1.1 | 69.9 | 28.2 | 23 | 26.9 |
| Female cadavers | 6.1 | 10.8 | 7.8 | 7.2 | 2.3 | |
| Total | 1.1 | 69.9 | 19.1 | 10.2 | 21.9 | |
|
| ||||||
| Variants with fusion between PM and deltoid muscle | Observed only in two male cadavers | 0.3 | 3.5 | 1.9 | 1.9 | 2.3 |
|
| ||||||
| Atrophy of the clavicular part of PM | Observed only in one female cadaver | Asymmetry = 15.6% | ||||
|
| ||||||
| The width of the base of the deltopectoral triangle (i.e. the distance between origins of the clavicular parts of PM and the deltoid muscle) [mm] | ||||||
|
| ||||||
| Minimal value | Maximal value | Mean | Median | Standard deviation | ||
|
| ||||||
| Typical variants of PM | Male cadavers | 10.3 | 20.9 | 16.2 | 17.3 | 3.8 |
| Female cadavers | 15.3 | 30.8 | 23 | 22.9 | 6.6 | |
| Total | 10.3 | 30.8 | 20.2 | 18.5 | 6.4 | |
|
| ||||||
| Variants with separated clavicular part | Male cadavers | 13.4 | 38.6 | 20.5 | 19.3 | 7.4 |
| Female cadavers | 11.5 | 35.6 | 21.9 | 18.5 | 8.1 | |
| Total | 11.5 | 38.6 | 21.3 | 18.9 | 7.6 | |
|
| ||||||
| Variants with fusion between PM and deltoid muscle | Observed only in two male cadavers | 0 | 0 | 0 | 0 | 0 |
|
| ||||||
| Atrophy of the clavicular part of PM | Observed only in one female cadaver | 49.8 | 52.9 | 51.4 | 51.4 | 2.2 |