An eccentric anatomical variation of palmar vascular pattern: Report of surgical challenging vascular variation

The knowledge of variations in the vascular architecture of hand is of great importance to surgeons, orthopedicians, and plastic surgeons in microsurgical procedures following crush injuries of the hand and amputations. The efficiency of collateral circulation in hand is essential in few peripheral vascular diseases like Raynaud’s disease and harvesting of the radial artery for the coronary bypass graft. During routine dissection of the right upper limb of a 55-year-old male cadaver, we observed that the superficial palmar arch (SPA) is formed by the ulnar artery and completed by the first dorsal metacarpal artery. After completing the arch, dorsal metacarpal artery continued as princeps pollicis artery for the thumb. The common palmar digital artery supplying the contiguous side of index and middle fingers passed through the neural loop formed by the proper digital nerve supplying the radial side of the middle finger and joined with the unusually large first palmar metacarpal artery before dividing into proper digital arteries. The first palmar metacarpal artery also gave origin to radialis indicis artery which in turn ran deep to tendons of the index finger to reach index finger. The common palmar digital artery supplying the contiguous side of middle and ring fingers also passed through the neural loop formed by the proper digital nerve supplying the ulnar side of the middle finger. The deep palmar branch of ulnar artery gave proper digital artery to little finger.