Folia Morphol. Vol. 78, No. 1, pp. 71–78 DOI: 10.5603/FM.a2018.0052 O R I G I N A L A R T I C L E Copyright © 2019 Via Medica ISSN 0015–5659 journals.viamedica.pl Branching patterns of the foetal popliteal artery A. Rohan1, Z. Domagała1, S. Abu Faraj1, A. Karykowska1, J. Klekowski2, N. Pospiech2, S. Wozniak1, B. Gworys3 1Division of Anatomy, Wroclaw Medical University, Wroclaw, Poland 2Clinical and Dissecting Anatomy Students Scientific Club, Wroclaw Medical University, Wroclaw, Poland 3Division of Basic Sciences, Witelon State University of Applied Sciences, Legnica, Poland [Received: 14 February 2018; Accepted: 10 June 2018] Background: The objective of the study is to evaluate the popliteal artery topography and the origin variability of its branches in human foetuses at the gestational age of from 4 to 9 months. The basis for the analysis are direct observations of classic anatomic dissections of the popliteal fossa. Possible dimorphic and bilateral differen- ces, as well as the gestational age variability at the foetal period, were considered. A typology of popliteal artery branches will be made on the basis of the studies. Materials and methods: The research material of this study comprises 231 foetuses (including 116 males and 115 females). The foetuses were divided into five 28-day age classes. The vessels of the lower extremity were injected with LBSK 5545 latex through the femoral artery. The bilateral dissection of the po- pliteal artery along with its branches was performed. No visible malformations were found in the research material, and the foetuses came from spontaneous abortions and premature births. Results and Conclusions: Ten per cent of the cases featured the variations of popliteal artery terminal branches. Three most commonly seen variations are the trifurcation, anterior tibial-peroneal trunk, and high terminal division of the po- pliteal artery. The most common course of the superior muscular branches is that there are two large branches which are distributed from the popliteal artery at the height of the knee joint cavity and they do not distribute cutaneous branches. Sural branches are also present as two large vessels without cutaneous branches. The genicular anastomosis branches that run on their own are a typical topographic system of these branches. (Folia Morphol 2019; 78, 1: 71–78) Key words: popliteal artery branches, popliteal artery topography, human foetuses INTRODUCTION minal angioplasty (PTA) or embolectomy. It is signif- Knowledge of the development at embryonic icant for clinicians to distinguish between an artery and foetal periods that determine the anatomical blockage or artery injury and the occurrence of artery variability of the cardiovascular system is of extreme variations, which is a result of being aware of possible significance to anatomists, surgeons and radiologists variations of the artery. Lack of such knowledge leads [3, 7, 25]. The variability of the course and the occur- to the development of complications during vascular rence of popliteal artery variations may have clinical surgeries [14]. implications for vascular transplants, indications for The objective of the study is to evaluate the pop- direct surgical intervention, percutaneous translu- liteal artery topography and the origin variability of Address for correspondence: Dr. Z. Domagala, Division of Anatomy Department of Morphology and Human Embryology, Wroclaw Medical University, ul. T. Chalubinskiego 6a, 50–368 Wrocław, Poland, e-mail: [email protected] 71 Folia Morphol., 2019, Vol. 78, No. 1 its branches in human foetuses at the gestational age Table 1. Sample sizes in successive gestational age classes of from 4 to 9 months. The basis for the analysis are Male Gestational age [month] Female direct observations of classic anatomic dissections of 20 4 22 the popliteal fossa. Possible dimorphic and bilateral 21 5 23 differences, as well as the gestational age variability 22 6 23 at the foetal period, were considered. A typology of 22 7 19 popliteal artery branches will be made on the basis 20 8 19 of the studies. 11 9 9 MATERIALS AND METHODS 116 Σ 115 The research material of this study comprises 231 foetuses (including 116 males and 115 females) at the gestational age from 84 to 224 days, stored in forma- Based on the analytics platform Statistica 10, the lin solution. The material comes from the collection evaluation of bilateral differences was made by means of the Department and Division of Normal Anatomy of the Wilcoxon signed-rank test. The significance of Wroclaw Medical University. Study has the Local evaluation of dimorphic and gestational age differ- Bioethics Commission acceptance. The foetuses were ences was made using the Kruskal-Wallis test. divided into five 28-day age classes. The vessels of the lower extremity were injected with LBSK 5545 latex RESULTS through the femoral artery. The bilateral dissection of It was found that the beginning of the popliteal the popliteal artery along with its branches was per- artery is determined by the adductor hiatus in all 462 formed. No visible malformations were found in the cases. It is a transition from the femoral artery to the research material, and the foetuses came from spon- popliteal artery. It was found that the diameter of the taneous abortions and premature births. The list of hiatus varied. However, regardless of the width of the the gestational age of the foetuses is shown in Table 1. adductor hiatus a typical course of the artery in the The gestation age of the foetuses was evaluated popliteal fossa is as follows: it is slightly covered by the on the basis of the last menstruation of the mother terminal insertion of the semimembranosus muscle in and verified by means of the method suggested by the proximal part of the popliteal fossa. The artery runs Gworys [8] where 4 of 16 characteristics were rele- between both heads of the gastrocnemius muscle, vant to determine age — body weight and length, and, on the sagittal side, under the plantaris muscle. circumference of head and chest. The artery runs along the popliteal surface of the femur, For the evaluation of popliteal artery topography then along the posterior wall of the articular capsule varieties and popliteal artery branches, both Adachi [2] of the knee joint, and along the oblique popliteal lig- and Lippert and Pabst [16] typologies were consid- ament in the further part of the popliteal fossa. Along ered, including the Kim et al. modification [14]. Both with the artery, the popliteal vein runs through the Adachi [2] and Lippert and Pabst [16], as well as other adductor hiatus. The vein lies more superficially than authors dealing with the anatomy of the popliteal the artery, and it covers the artery incompletely. The artery, placed their emphasis on the last portion of covering degree varies individually. Both vessels are the popliteal artery, that is on the observation of the covered by the same vascular sheath. From the sheath, variability of its terminal division. We could not find the tibial nerve runs superficially, which moves along the detailed description of the artery course in the the entire length of the popliteal fossa from the medial available source literature. The analysis of the collected side of the sheath to the lateral side. In the distal angle dissectional material (462 lower extremities) allowed us of the popliteal fossa, the popliteal artery is divided to evaluate the origin level and symmetry of the artery into the anterior and posterior tibial arteries. branches. It enabled us to determine the artery course An unusual course of the popliteal artery at the in relation to the knee joint, walls of the popliteal fossa, foetal state was found in 30 extremities altogether, popliteal fascia and in relation to other components of including 18 males and 12 females. We distinguished the neurovascular bundle. The variability of the popliteal two types of the artery course: type I — the typical artery terminal division was also analysed. course, i.e. the artery is covered by a homonymous 72 A. Rohan et al., Branching patterns of the foetal popliteal artery Table 2. Typology of the popliteal artery course at the foetal period Male Gestation Female Right side type Left side type age Right side type Left side type I II I II [month] I II I II 20 0 20 0 4 21 1 22 0 19 2 20 1 5 22 1 22 1 20 2 19 3 6 23 0 21 2 21 1 20 2 7 17 2 18 1 17 3 18 2 8 17 2 18 1 11 0 9 2 9 8 1 9 0 108 8 106 10 Σ 108 7 110 5 Table 3. Typology of the superior muscular branches in the foetuses Male Gestation Female Right side type Left side type age Right side type Left side type I II III I II III [month] I II III I II III 8 8 4 9 8 3 4 10 9 3 11 11 2 10 8 3 8 9 4 5 10 11 2 11 9 3 8 9 5 9 10 3 6 8 12 3 9 12 2 6 11 5 7 11 4 7 6 9 4 5 10 4 6 10 4 5 13 2 8 5 9 5 5 10 4 2 6 3 2 5 4 9 2 5 2 1 5 3 40 52 24 40 56 20 Σ 41 55 19 42 57 18 vein, and lies slightly medially from it; type II — the of superior muscular branches in the foetuses were artery lies laterally from the popliteal vein. Within distinguished: type I — no superior muscular branch- those two types there was found 10 cases (6 male, es, type II — which features two branches, and type 4 female) where the artery was covered by the medial III — with three branches.