With regard to intercostal spaces:

Let’s carefully check each option about intercostal spaces:


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A. the neurovascular bundle runs in the plane between external intercostal and internal intercostal muscles
❌ False – The main intercostal vein, artery, and nerve (VAN) run in the neurovascular plane between the internal intercostal and innermost intercostal muscles.


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B. neurovascular structures lie in the order of nerve, artery, vein from above downwards
❌ False – The correct order in the costal groove (from above downwards) is vein, artery, nerve (VAN).


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C. the upper two spaces are supplied by the supreme intercostal artery
✅ True – The supreme (highest) intercostal artery, a branch of the costocervical trunk (from subclavian), supplies the first two intercostal spaces.


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D. the collateral branches of the intercostal artery and nerve run along the upper border of the rib that forms the lower boundary of the space
✅ True – The collateral branches course along the upper border of the rib below, opposite the main VAN in the costal groove (which runs along the lower border of the rib above).


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E. the collateral branch of the intercostal nerve supplies skin over the space
❌ False – The lateral cutaneous and anterior cutaneous branches supply the skin. The collateral branch mainly helps supply the intercostal muscles and parietal pleura, not the overlying skin.


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✅ Correct answers: C and D