August 2007 Vol 7 copy.indd ABSTRACT Bilateral absence of the arcuate artery was observed during routine dissection of the lower limbs of a 60-year-old male cadaver. Running distally on the dorsal aspect of both feet and opposite the tarso-metatarsal joint, the dorsalis pedis artery diverged 2cm lateral to the tendon of the extensor hallucis longus. The 2nd dorsal metatarsal artery was found originating from the dorsalis pedis artery opposite the intermediate cuneiform bone. The 3rd and 4th dorsal metatarsal arteries originated from the lateral tarsal artery. Although absence of the arcuate artery has been previously described, the arterial variant described here is thought to be dis- tinct from those previously reported. The variant 2nd dorsal metatarsal artery was found to originate from the dorsalis pedis artery. Knowledge of anatomical variations of arteries supplying the feet and toes has important clinical significance in reconstructive surgery and in determining associated pathology. Keywords: Anatomy, Tarsal; Dorsal; Metatarsal; Arcuate; Pedis; Arteries; Case Report; Oman. Bilateral Absence of the Arcuate Artery on the Dorsum of the Foot With anomalous origin of dorsal metatarsal arteries Nilesh K Mitra, *Omar A Habbal, Abdulghaffar H El-Hag, Nasser A Al-Hashmi SULTAN QABOOS UNIVERSITY MEDICAL JOURNAL AUGUST 2007 VOL 7, NO. 2, P. 153-155 SULTAN QABOOS UNIVERSITY© SUBMITTED - 6TH MARCH 2007 NUMEROUS VARIATIONS OF THE ARTERIAL anatomy of the foot and toes have been described.1, 2, 3, 4 Awareness of the anatomical variations in arteries of the foot and toes is important for angiographers, vascular surgeons and reconstruc- tive surgeons to deal with diagnosis and treatment of arterial occlusive diseases. The dorsal artery of the foot, arteria dorsalis pedis, dorsalis pedis artery, is the con- tinuation of the anterior tibial artery distal to the ankle. It courses distally along the dorsum of the foot to the proximal end of the 1st intermetatarsal space, where it turns into the sole to complete the plantar arch. The branches of the dorsalis pedis include the lateral and medial tarsal, 1st dorsal metatarsal, deep plantar and arcuate arteries. The arcuate artery arises near the me- dial cuneiform, passes laterally over the metatarsal bas- es deep to the digital extensor tendons and gives rise to the 2nd to 4th dorsal metatarsal arteries (DMAs) before anastomising with the lateral tarsal artery.5 The DMAs are important as they are responsible for the blood sup- Department of Human and Clinical Anatomy, College of Medicine and Health Sciences, Sultan Qaboos University, P. O. Box 35, Al-Khod 123, Sultanate of Oman *To whom correspondence should be addressed. Email: habbal@squ.edu.om C A S E R E P O R T منابت في تغيرات وجود مع كال القدمني ظهر من املقوَس الشريان غياب الظهرية (العرشية) املشطيِِة الشرايني الهاشمي عايش ناصر احلاج، حسني الغفار عبد احلبال، الرحمن عبد عمر مترا، نيليش كومار ، القدمني ظهركال من املقوس ــريان الش غياب لوحظ عاماً، ــتون س العمر من يبلغ ذكر جلثة ــفلية الروتيني لألطراف الس ــريح التش امللخص: خالل 2 سنتيمتر متنحياً الشريان القدمي الظهري شوهد كما الرسغي-املشطي. املفصل مقابل للقدمني الظهرية الناحية يجتازان كالهما حيث وجد املقوس الظهري ــريان من الش ــطي الظهري الثاني كان ــريان املش الش وأن منبت الطويلة. ــطة الباس القدم إبهام عضلة وتد من ــي الوحش للجانب ــغي الرس ــريان الش كانت منابتهما من فلقد والرابع الظهريني الثالث ــطيني املش ــريانني أما الش ــطة. املتوس (الوتدية) ــفينية الس العظمة قبالة عن ومتميزة قبل توصف من لم الشريانية من املتغيرات نصفه هنا ما املقوس فإن الشريان لغياب ــبق املس الوصف وجود الرغم من وعلى ــي. الوحش معرفة املتغيرات وإن الظهري. القدمي الشريان من مبتدئاً وجد الثاني الظهري املشطي الشريان منبت بديل أن حيث ، التشريحية املتغيرات من غيرها املتغيرات. لهذه املرضية املتالزمات عن والبحث الترميم جراحة مجاالت في خاص وبشكل سريرية لها أهمية واألصابع األقدام لشرايني التشريحية عمان. حالة، تقرير قدمي، مشطي، ظهري، شرايني، الكلمات: تشريح، مفتاح M I T R A N K , H A B B A L O, E L - H A G A H A N D A L - H A S H M I N A 154 ply to the toes through their digital branches. Also, free transfer of flaps from the web spaces of toes contain- ing DMAs are used for micro-vascular anastomosis in reconstruction of the hand.6 The following is a report of bilateral absence of the arcuate artery with variations in origin of the 2nd, 3rd, and 4th dorsal metatarsal arteries found during routine gross anatomy dissection at the College of Medicine and Health Sciences, Sultan Qaboos University, Sul- tanate of Oman C A S E R E P O R T During routine dissection of the lower limbs of a 60- year-old male cadaver, it was observed that the arcu- ate artery on the dorsum of the foot was absent bi- laterally [Figs. 1 & 2]. After reflection of the tendons of the extensor digitorum longus (EDL) and extensor digitorum brevis (EDB) muscles, the dorsalis pedis ar- tery was cleaned, along with accompanying veins and traced distally. It entered the 1st intermetatarsal space where it gave rise to the 1st DMA. In both lower limbs, the artery was also found to give rise to the 2nd dorsal metatarsal artery (DMA) opposite the intermediate cuneiform bone (the usual point of origin of the arcu- ate artery) [Figure 1]. The 2nd DMA passed forward between the 2nd and 3rd metatarsal bones resting on the belly of the 2nd dorsal interosseous muscle. The 3rd and 4th DMA were found to arise from the lat- eral tarsal artery opposite the lateral cuneiform and cuboid bones [Figure 1]. The 2nd through 4th DMAs originated much more proximally than their usual textbook description of origin at the bases of the met- atarsals. Similarly, the lateral tarsal artery also arose much more proximally and laterally over the dorsal aspect of the calcaneus. In the absence of the arcuate artery, it ended anteriorly by dividing into the 3rd and 4th DMAs. A muscular branch from the lateral tarsal artery was found, as usual, joining to the EDB, and a lateral branch joined the lateral malleolar network. D I S C U S S I O N Anomalies of the dorsalis pedis artery and its branches on the dorsum of the foot have been mostly reported in cadaveric dissections1,2,3,4,7,8,9 Out of these studies, Yamada et al.2 and DiLandro et al.4 reported variations in the arcuate artery. Dissection, arteriographic and corrosion cast studies by Yamada et al.2 involving 30 limbs from 17 cadavers revealed that the arcuate ar- tery was absent in 33% of feet and the dorsalis pedis artery was absent in 6.7% of feet. In our case, we re- port bilateral absence of the arcuate artery in a male cadaver. Yamada et al. (1993) found no strong associa- tion between the right and left feet of the same person for the presence of the arcuate artery. DiLandro et al.4 reported the absence of the arcuate artery in 83.3% of cases Variations in dorsal metatarsal arteries have been reported in several studies.1, 4, 8, 9 The 1st dorsal meta- tarsal artery was found to originate from its usual ori- gin, the dorsalis pedis artery, in 90.6%1, 4, 8, 9 and 86% of cases.9 Lee and Dauber8 reported anomalous origin of the 1st dorsal metatarsal artery from the lateral tarsal artery in only 9.4% cases and it was also found to arise from the plantar network in 10% of cases.9 Our study found no variation in origin of the 1st dorsal metatarsal artery. The arcuate artery is classically described as giving rise to the 2nd to 4th dorsal metatarsal arteries.5 In the study by Gabrielli and Olave9 the 2nd DMA originated from the arcuate artery exclusively in 10% of cases, the 3rd DMA in 6% of cases and the 4th DMA in 10% of cases. In its absence (48%), the lateral tarsal arteries and the proximal perforating branches were respon- Figure 1: Photograph of the dissected right foot showing the dorsalis pedis artery giving origin to the 1st and 2nd dorsal metatarsal artery (DMA) and absence of arcuate artery. The 3rd and 4th DMA are seen to be arising from the lateral tarsal artery. Arrow shows lateral diversion of the dorsalis pedis artery 2 cm away from the tendon of EHL. 1. dorsalis pedis artery; 2. 1st DMA; 3. 2nd DMA; 4. 3rd DMA; 5. 4th DMA; 6. lateral tarsal artery; 7. medial division of the deep peroneal nerve. Extensor hallucis longus (EHL); extensor digitorum brevis (EDB); extensor digitorum longus (EDL) B I L AT E R A L A B S E N C E O F T H E A R C UAT E A R T E R Y O N T H E D O R S U M O F T H E F O O T W I T H A N O M A L O U S O R I G I N O F D O R S A L M E TATA R S A L A R T E R I E S 155 sible for the formation of the second DMA in 52%, of the third DMA in 54%, and of the fourth DMA in 72% of cases. The proximal perforating branches made an important contribution to the formation of such ar- teries, contributing partially or totally to the second DMA in 90%, to the third DMA in 92%, and to the fourth DMA in 86%.4, 9 in 72 cadaveric dissections, found that the lateral tarsal artery supplied the 2nd, 3rd, and 4th DMA more frequently (47.2%) than the arcu- ate artery. The proximal perforating arteries as well as various combinations of all three sources were also found to contribute complete blood supply to dorsal metatarsal arteries 2 through 4. In our study the 3rd and 4th DMA arose from the lateral tarsal artery. C O N C L U S I O N The anatomical variation in this report describes the 2nd DMA as originating from the dorsalis pedis artery when the arcuate artery was found to be absent. To the best of our knowledge, this variation is distinct and has not yet been reported. Even studies by Gabrielli and Olave9 found that in the absence of the arcuate artery, the lateral tarsal arteries (52% of cases) and proximal perforating arteries (90% of cases) were re- sponsible for the origin of the 2nd DMA. Documenta- tion of anomalous origins of the 2nd, 3rd, and 4th dorsal metatarsal arteries, such as reported in this case study, is important to clinicians doing reconstructive surger- ies of the foot. A C K N OW L E D G ME N TS We thank all Dissection Room staff of the Department of Human and Clinical Anatomy at Sultan Qaboos University, Oman, for their assistance and support in this study. R E F E R E N C E S 1. Hamada N, Ikuta Y, Ikeda A. Arteries to the great and second toes based on three-dimensional analysis of 100 cadaveric foot. Surg Radiol Anat 1993;15:187-192. 2. Yamada T, Gloviczki P, Bower TC, Naessens JM, Car- michael SW. Variations of the arterial anatomy of the foot. Am J Surg 1993;166:130-135. 3. Tuncel M, Maral T, Celik H, Tascioglu B. A case of bilateral anomalous origin for dorsalis pedis arteries (anomalous dorsalis pedis arteries). Surg Radiol Anat 1994;16:319-323. 4. DiLandro AC, Lilja EC, Lepore FL, Viscovich JB, Cam- pion N, Datta UK, Signorile J. The prevalence of the ar- cuate artery: a cadaveric study of 72. J Am Podiatr Med Assoc 2001; 91:300-305. 5. Standring S, Ellis H, Healy J, Johnson D, Williams A. Pelvic Girdle and Lower limb. In Sandring S, ed. Gray’s Anatomy: The Anatomical Basic for Clinical Practice. 39th ed. Edinburgh: Elsvier, Churchill Livingstone, 2005. p. 1600. 6. Rose EH, Buncke HJ. Free transfer of a large sensory flap from the first web space and dorsum of the foot in- cluding the second toe for reconstruction of a mutilated hand. J Hand Surg 1981; 6:196-201. 7. Chiba S. Two cases of the superficial dorsalis pedis ar- tery observed in man. Anat Anz 1996; 178:183-189. 8. Lee JH, Dauber W. Anatomical study of the dorsa- lis pedis-first dorsal metatarsal artery. Ann Plast Surg 1997; 38:50-55. 9. Gabrielli C, Olave E. Origins of the dorsal metatarsal arteries in humans. Scand J Plast Reconstr Surg Hand Surg 2002; 36:221-225. Figure 2: Schematic representation showing com- parison between normal and anomalous origin of the DMAs (1-4). The left-sided figure shows the normal description of the 1st DMA arising from the dorsalis pedis artery and the 2nd, 3rd, and 4th DMAs arising from the arcuate artery. The right- sided figure shows the variations found in this study; normal origin of the 1st DMA arising from the dorsalis pedis artery and anomalous origins of the 2nd DMA from the dorsalis pedis artery, and the 3rd and 4th DMAs from the lateral tarsal artery. D- dorsalis pedis artery; A- arcuate artery; L- lateral tarsal artery