Surg Radiol Anat DOI 10.1007/s00276-014-1261-2
Original Article
Can we consider standard microsurgical anastomosis on the posterior tibial perforator network? An anatomical study Harold Eburdery · Benoît Chaput · Aymeric Andre · Jean‑Louis Grolleau · Jean‑Pierre Chavoin · Frederic Lauwers
Received: 22 October 2013 / Accepted: 17 January 2014 © Springer-Verlag France 2014
Abstract Purpose The main vessels in an injured leg can be spared with perforator-to-perforator anastomosis. However, supermicrosurgery is not a routine procedure for all plastic surgeons. Our objective was to establish if the diameter of the perforators of the leg could allow anastomosis with standard microsurgical procedures. Methods Twenty lower legs harvested from ten fresh cadavers were dissected. Arterial and venous vessels were injected with colored latex. The limbs were then dissected in a suprafascial plane. All the perforating arteries of a diameter >0.8 mm were located and their external diameter, the number and external diameter of the venae comitantes were reported. Results We found at least three tibial posterior artery perforators with diameters >0.8 mm per leg with a mean external diameter of 1.1 mm and one vena comitans in almost all cases (96 %). The vena comitans was usually bigger than the perforating artery with a mean diameter of 1.6 mm. After statistical analysis, we were able to locate two main perforator clusters: at the junctions of the upper two-thirds of the leg and of the lower two-thirds of the leg. Conclusion The low-morbidity concept of perforator-toperforator anastomosis can apply to posterior tibial artery perforators without using supermicrosurgical techniques.
H. Eburdery (*) · B. Chaput · A. Andre · J.-L. Grolleau · J.-P. Chavoin Plastic and Reconstructive Surgery Unit, CHU Toulouse Rangueil, 1 avenue Jean Poulhès, 31400 Toulouse, France e-mail: [email protected] F. Lauwers Anatomy laboratory, Faculty of Medecine Rangueil, University Paul Sabatier, 133 Route de Narbonne, 31400 Toulouse, France
This is of high interest for open leg fractures where main vessels could be injured. We hope that the results of our study will incite surgeons to consider sparing of main vessels for coverage of open leg fractures whether surgical teams master supermicrosurgery or not. Keywords Anatomical study · Supermicrosurgery · Posterior tibial perforators · Perforating veins · Leg perforators · Perforator-to-perforator anastomosis
Introduction Knowledge of skin vascularization advanced a lot these last years [23, 27]. At the same time, supermicrosurgery, defined by anastomosis of 0.8 mm) in the medial leg for all subjects and constant venae comitantes with diameters allowing anastomosis on the same operating site. Localization of the clusters of perforators is interesting, but presurgical mapping stays mandatory before surgery because of the variability between subjects. A good definition of the clusters can only facilitate presurgical mapping. We chose to work on tibial posterior artery because it is reported in the literature to have the largest perforator vessels in the leg [1, 2, 24]. The localization, diameter and venae comitantes of arterial perforators larger than 0.8 mm were specifically studied. Perforating veins are far less studied than the arteries and our study is the first to our knowledge to study the perforating veins of the posterior tibial network.
Method Injection Twenty legs of ten fresh cadavers (6 men, 4 women; 64– 97 years) were studied. There was no evidence of previous surgery, major trauma or peripheral vascular disease.
13
We used prevulcanised latex (Esprit Composite®) and red and blue liquid acrylic ink (Pébéo® Artist Acrylics Liquid Vermilion 37 and Ultramarine Blue 08) for injections. All cadavers underwent an amputation at knee level. The posterior tibial pedicle was dissected posterior to the medial malleolus. This approach was as limited and atraumatic as possible in order to prevent further latex leaks. The posterior tibial venae comitantes were catheterized. The posterior tibial artery and its venae comitantes were irrigated with warm saline to flush out clots until effluent was clear (Fig. 1a). All vessels at the level of amputation were tied from the biggest to the smallest. Saline flush was repeated between each ligature to ensure that the entire venous network had been flushed. Isolation of the arterial and venous networks of the leg allows high-pressure latex injection so that these networks should be entirely filled. The latex was then injected at the ankle until latex leaked at the amputation level (Fig. 1b). The legs were left at room temperature for 1 day to allow latex to cure before being dissected. Dissection A vertical landmark crossing the middle of the ankle and a horizontal landmark at the level of the tip of the medial malleolus were made on each leg. These landmarks were used to localize perforators. We measured the length of the leg from the tibial tray to the tip of the medial malleolus. The external diameter of tibial posterior artery and the number and external diameter of its venae comitantes were also measured at retromaleolar level. A skin incision along the anterior tibial crest was then performed and a hemicircumferential subcutaneous flap was harvested from this incision
Surg Radiol Anat
results and allow comparison between subjects. A calliper ruler was used in the dissection room to screen perforators larger than 0.8 mm. The precise external diameter of the perforating vessels was then determined with a measuring tool based on scaled photographs, using the free access software image J® (http://imagej.nih.gov/ij/).
Results (Table 1)
Fig. 2 Injected arterial (red) and venous (blue) tibial posterior networks (color figure online)
Fig. 3 Measures of the perforating artery and vein
(Fig. 2). Each perforating artery larger than 0.8 mm was listed along with its position and external diameter. The number and external diameter of the venae comitantes were also registered (Fig. 3). The perforators were localized in percentage of the total length of the leg to standardize the
The mean length of the leg was 358 mm (294–420). The external diameter of the posterior tibial artery was 3.3 mm (1.8–4.6, SD 0.7). There were always two venae comitantes with the artery except in one leg (5 %) where there were three. Their external diameter was 2.93 mm (1.2–3.5, SD 0.52). These latter were smaller than the artery in 80 % of the cases. In all, 75 perforating arteries were larger than 0.8 mm in the study. The mean number of large perforating arteries per leg was 3.75 (3–6). The mean external diameter of all the perforating arteries was 1.1 mm (0.8–2.3, SD 0.27). The mean number of venae comitantes for these arteries was 1.1. We could not find any vein for three perforating arteries (4 %) on three different legs, the mean diameter of these arteries without venae comitantes was 0.87 mm (0.80–0.97). We found one vena comitans per perforating artery in 61 cases (81 %), with a mean diameter of 1.1 mm (0.8–2.3) for these one-vein arteries. We found two venae comitantes per perforating artery in 11 cases (15 %), with a mean diameter of 1.2 mm (0.8–1.8) for these two-vein arteries. The perforators’ diameter was not larger in the leg with few perforators than in the leg with many perforators [1.1 mm for legs with 3 perforators (n = 11); 1.2 mm for legs with 6 perforators (n = 2)]. The mean diameter of the venae comitantes was 1.6 mm (0.6–2.9, SD 0.52). The smallest veins were seen when there were two venae comitantes per perforating artery. If we consider only the unique vena comitans or the biggest out of two, the minimal diameter is 0.8 mm and the vein is bigger than the perforating artery in 84 %. Make Human® (http://www.makehuman.org/), an open source software designed to model characters, was used to
Table 1 Arterial and venous posterior tibial network Posterior tibial perforating vein n = 83
Posterior tibial vein n = 41 (retromalleolar level)
Retromalleolar diameter (mm)
Number per leg Diameter (mm) Number per leg Diameter (mm) Number per leg Diameter (mm)
Average 3.3 Range 1.8–4.6 SD
Posterior tibial perforating artery n = 75
Posterior tibial artery n = 20
0.70
2.05 2–3
2.93 1.2–3.5 0.52
3.75 3–6
1.1 0.8–2.3 0.27
1.1 0–2
1.6 0.6–2.9 0.52
13
Surg Radiol Anat
Fig. 4 Perforating arteries larger than 0.8 mm for each leg of the study
Fig. 6 Tibial posterior artery perforators’ distribution according to previous anatomical studies
Fig. 5 Whole distribution of the perforating arteries larger than 0.8 mm of the study
represent the legs in Figs. 4, 5 and 6. Each drawing of the leg has been scaled as the anatomic specimen, with the tip of the medial malleolus and the vertical line crossing the
13
middle of the ankle as landmarks. Each perforators represented on the drawing is at its exact localization. Most perforators are paratibial septocutaneous tibial posterior artery perforators arising between soleus and flexor digitorum longus muscles. There was an intra- and inter-individual variability regarding the perforator distribution, but we can find similar patterns of distribution in most legs (Fig. 4). We considered the whole perforator distribution in the 20 legs of our study (Fig. 5) to make a statistical analysis (Table 2).
Surg Radiol Anat Table 2 Statistical analysis of the distribution of the perforators using Poisson’s exact test Zone of the leg (distal to proximal)
Number of perforator (n)
n2
Comparison with Poisson’s exact test
1 2 3 4 5 6 7
3 10 15 8 11 19 9
9 100 225 64 121 361 81
0.0116 0.1226 0.0246 0.1255 0.1045 0.0020 0.1308
8
0
0
0.0001
Expected number of perforator per zone if homogenous distribution = 9.375 Variance = 36.8393 Variance to mean ratio = 3.9295 > 1, the pattern of distribution is clustered p value = 0.05, significant results (1, we concluded that the perforator pattern was clustered. Next, in each subregions we have compared the observed number of perforators to the expected number (n = 75/8 = 9,375) using a Poisson’s exact test. Zone 3 (25–37.5 % of the height of the leg) and zone 6 (62.5– 75 % of the height of the leg) showed more perforators than expected (p
Original Article
Can we consider standard microsurgical anastomosis on the posterior tibial perforator network? An anatomical study Harold Eburdery · Benoît Chaput · Aymeric Andre · Jean‑Louis Grolleau · Jean‑Pierre Chavoin · Frederic Lauwers
Received: 22 October 2013 / Accepted: 17 January 2014 © Springer-Verlag France 2014
Abstract Purpose The main vessels in an injured leg can be spared with perforator-to-perforator anastomosis. However, supermicrosurgery is not a routine procedure for all plastic surgeons. Our objective was to establish if the diameter of the perforators of the leg could allow anastomosis with standard microsurgical procedures. Methods Twenty lower legs harvested from ten fresh cadavers were dissected. Arterial and venous vessels were injected with colored latex. The limbs were then dissected in a suprafascial plane. All the perforating arteries of a diameter >0.8 mm were located and their external diameter, the number and external diameter of the venae comitantes were reported. Results We found at least three tibial posterior artery perforators with diameters >0.8 mm per leg with a mean external diameter of 1.1 mm and one vena comitans in almost all cases (96 %). The vena comitans was usually bigger than the perforating artery with a mean diameter of 1.6 mm. After statistical analysis, we were able to locate two main perforator clusters: at the junctions of the upper two-thirds of the leg and of the lower two-thirds of the leg. Conclusion The low-morbidity concept of perforator-toperforator anastomosis can apply to posterior tibial artery perforators without using supermicrosurgical techniques.
H. Eburdery (*) · B. Chaput · A. Andre · J.-L. Grolleau · J.-P. Chavoin Plastic and Reconstructive Surgery Unit, CHU Toulouse Rangueil, 1 avenue Jean Poulhès, 31400 Toulouse, France e-mail: [email protected] F. Lauwers Anatomy laboratory, Faculty of Medecine Rangueil, University Paul Sabatier, 133 Route de Narbonne, 31400 Toulouse, France
This is of high interest for open leg fractures where main vessels could be injured. We hope that the results of our study will incite surgeons to consider sparing of main vessels for coverage of open leg fractures whether surgical teams master supermicrosurgery or not. Keywords Anatomical study · Supermicrosurgery · Posterior tibial perforators · Perforating veins · Leg perforators · Perforator-to-perforator anastomosis
Introduction Knowledge of skin vascularization advanced a lot these last years [23, 27]. At the same time, supermicrosurgery, defined by anastomosis of 0.8 mm) in the medial leg for all subjects and constant venae comitantes with diameters allowing anastomosis on the same operating site. Localization of the clusters of perforators is interesting, but presurgical mapping stays mandatory before surgery because of the variability between subjects. A good definition of the clusters can only facilitate presurgical mapping. We chose to work on tibial posterior artery because it is reported in the literature to have the largest perforator vessels in the leg [1, 2, 24]. The localization, diameter and venae comitantes of arterial perforators larger than 0.8 mm were specifically studied. Perforating veins are far less studied than the arteries and our study is the first to our knowledge to study the perforating veins of the posterior tibial network.
Method Injection Twenty legs of ten fresh cadavers (6 men, 4 women; 64– 97 years) were studied. There was no evidence of previous surgery, major trauma or peripheral vascular disease.
13
We used prevulcanised latex (Esprit Composite®) and red and blue liquid acrylic ink (Pébéo® Artist Acrylics Liquid Vermilion 37 and Ultramarine Blue 08) for injections. All cadavers underwent an amputation at knee level. The posterior tibial pedicle was dissected posterior to the medial malleolus. This approach was as limited and atraumatic as possible in order to prevent further latex leaks. The posterior tibial venae comitantes were catheterized. The posterior tibial artery and its venae comitantes were irrigated with warm saline to flush out clots until effluent was clear (Fig. 1a). All vessels at the level of amputation were tied from the biggest to the smallest. Saline flush was repeated between each ligature to ensure that the entire venous network had been flushed. Isolation of the arterial and venous networks of the leg allows high-pressure latex injection so that these networks should be entirely filled. The latex was then injected at the ankle until latex leaked at the amputation level (Fig. 1b). The legs were left at room temperature for 1 day to allow latex to cure before being dissected. Dissection A vertical landmark crossing the middle of the ankle and a horizontal landmark at the level of the tip of the medial malleolus were made on each leg. These landmarks were used to localize perforators. We measured the length of the leg from the tibial tray to the tip of the medial malleolus. The external diameter of tibial posterior artery and the number and external diameter of its venae comitantes were also measured at retromaleolar level. A skin incision along the anterior tibial crest was then performed and a hemicircumferential subcutaneous flap was harvested from this incision
Surg Radiol Anat
results and allow comparison between subjects. A calliper ruler was used in the dissection room to screen perforators larger than 0.8 mm. The precise external diameter of the perforating vessels was then determined with a measuring tool based on scaled photographs, using the free access software image J® (http://imagej.nih.gov/ij/).
Results (Table 1)
Fig. 2 Injected arterial (red) and venous (blue) tibial posterior networks (color figure online)
Fig. 3 Measures of the perforating artery and vein
(Fig. 2). Each perforating artery larger than 0.8 mm was listed along with its position and external diameter. The number and external diameter of the venae comitantes were also registered (Fig. 3). The perforators were localized in percentage of the total length of the leg to standardize the
The mean length of the leg was 358 mm (294–420). The external diameter of the posterior tibial artery was 3.3 mm (1.8–4.6, SD 0.7). There were always two venae comitantes with the artery except in one leg (5 %) where there were three. Their external diameter was 2.93 mm (1.2–3.5, SD 0.52). These latter were smaller than the artery in 80 % of the cases. In all, 75 perforating arteries were larger than 0.8 mm in the study. The mean number of large perforating arteries per leg was 3.75 (3–6). The mean external diameter of all the perforating arteries was 1.1 mm (0.8–2.3, SD 0.27). The mean number of venae comitantes for these arteries was 1.1. We could not find any vein for three perforating arteries (4 %) on three different legs, the mean diameter of these arteries without venae comitantes was 0.87 mm (0.80–0.97). We found one vena comitans per perforating artery in 61 cases (81 %), with a mean diameter of 1.1 mm (0.8–2.3) for these one-vein arteries. We found two venae comitantes per perforating artery in 11 cases (15 %), with a mean diameter of 1.2 mm (0.8–1.8) for these two-vein arteries. The perforators’ diameter was not larger in the leg with few perforators than in the leg with many perforators [1.1 mm for legs with 3 perforators (n = 11); 1.2 mm for legs with 6 perforators (n = 2)]. The mean diameter of the venae comitantes was 1.6 mm (0.6–2.9, SD 0.52). The smallest veins were seen when there were two venae comitantes per perforating artery. If we consider only the unique vena comitans or the biggest out of two, the minimal diameter is 0.8 mm and the vein is bigger than the perforating artery in 84 %. Make Human® (http://www.makehuman.org/), an open source software designed to model characters, was used to
Table 1 Arterial and venous posterior tibial network Posterior tibial perforating vein n = 83
Posterior tibial vein n = 41 (retromalleolar level)
Retromalleolar diameter (mm)
Number per leg Diameter (mm) Number per leg Diameter (mm) Number per leg Diameter (mm)
Average 3.3 Range 1.8–4.6 SD
Posterior tibial perforating artery n = 75
Posterior tibial artery n = 20
0.70
2.05 2–3
2.93 1.2–3.5 0.52
3.75 3–6
1.1 0.8–2.3 0.27
1.1 0–2
1.6 0.6–2.9 0.52
13
Surg Radiol Anat
Fig. 4 Perforating arteries larger than 0.8 mm for each leg of the study
Fig. 6 Tibial posterior artery perforators’ distribution according to previous anatomical studies
Fig. 5 Whole distribution of the perforating arteries larger than 0.8 mm of the study
represent the legs in Figs. 4, 5 and 6. Each drawing of the leg has been scaled as the anatomic specimen, with the tip of the medial malleolus and the vertical line crossing the
13
middle of the ankle as landmarks. Each perforators represented on the drawing is at its exact localization. Most perforators are paratibial septocutaneous tibial posterior artery perforators arising between soleus and flexor digitorum longus muscles. There was an intra- and inter-individual variability regarding the perforator distribution, but we can find similar patterns of distribution in most legs (Fig. 4). We considered the whole perforator distribution in the 20 legs of our study (Fig. 5) to make a statistical analysis (Table 2).
Surg Radiol Anat Table 2 Statistical analysis of the distribution of the perforators using Poisson’s exact test Zone of the leg (distal to proximal)
Number of perforator (n)
n2
Comparison with Poisson’s exact test
1 2 3 4 5 6 7
3 10 15 8 11 19 9
9 100 225 64 121 361 81
0.0116 0.1226 0.0246 0.1255 0.1045 0.0020 0.1308
8
0
0
0.0001
Expected number of perforator per zone if homogenous distribution = 9.375 Variance = 36.8393 Variance to mean ratio = 3.9295 > 1, the pattern of distribution is clustered p value = 0.05, significant results (1, we concluded that the perforator pattern was clustered. Next, in each subregions we have compared the observed number of perforators to the expected number (n = 75/8 = 9,375) using a Poisson’s exact test. Zone 3 (25–37.5 % of the height of the leg) and zone 6 (62.5– 75 % of the height of the leg) showed more perforators than expected (p
