Anatomical considerations of the sural nerve in the distal leg: Side branch patterns and significance in nerve harvesting procedures.

BACKGROUND: The sural nerve is a somatosensory nerve that provides sensation to the posterolateral aspect of the lower leg and the lateral part of the ankle and foot. Due to its location and anatomical properties, it is often used as an autologous nerve graft. However, the nerve harvest can be complicated by the presence of side branches. The objective of this study was to investigate the anatomy of the sural nerve and to map its side branches. This information can be used to predict the localization of separate incisions during the stair-step incisions technique for nerve harvest, thereby reducing the risk of complications. METHODS: The study involved the dissection of 50 adult cadaveric legs (25 left and 25 right) obtained from 27 Central European cadavers. The focus of the dissection was to identify the sural nerve, small saphenous vein, and surrounding anatomical structures. Detailed measurements were taken on the side branches of the sural nerve, tributaries of the small saphenous vein, and their interrelationship. RESULTS: The average number of sural nerve side branches in a single leg was 4.2±1.9. These side branches were categorized into six groups based on their location and course: mediodistal, medioproximal, lateroproximal, laterodistal, medial perpendicular, and lateral perpendicular. Specific patterns of combination of these side branches were also identified and described. The branching point of the sural nerve was found to be 5.8±2.7 cm proximal to the lateral malleolus, whereas the small saphenous vein branching point was located more distally, 4.5 ± 2.8 cm proximal to the lateral malleolus. The highest density of sural nerve side branches was found 2.1-6.0 cm above the lateral malleolus. CONCLUSION: This study presents valuable data about the relationship between the sural nerve and the surrounding anatomical structures in the distal part of the leg, including the identification of its side branches and their relevance during nerve harvest procedures. On the basis of the most frequent locations of side branches, a three-incision-technique for nerve harvest is proposed.

Syndesmotic Fixation With Suture Button: Neurovascular Structures at Risk: A Cadaver Study.

OBJECTIVES: The objective of this study was to describe the anatomic variations in the saphenous nerve and risk of direct injury to the saphenous nerve and greater saphenous vein during syndesmotic suture button fixation. METHODS: Under fluoroscopic guidance, syndesmotic suture buttons were placed from lateral to medial at 1, 2, and 3 cm above the tibial plafond on 10 below-knee cadaver leg specimens. The distance and position of each button from the greater saphenous vein and saphenous nerve were evaluated. RESULTS: The mean distance of the saphenous nerve to the suture buttons at 1, 2, and 3 cm were 7.1 ± 5.6, 6.5 ± 4.6, and 6.1 ± 4.2, respectively. Respective rate of nerve compression was as follows, 20% at 1 cm, 20% at 2 cm, and 10% at 3 cm. Mean distance of the greater saphenous vein from the suture buttons at 1, 2, and 3 cm was 8.6 ± 7.1, 9.1 ± 5.3, and 7.9 ± 4.9 mm, respectively. Respective rate of vein compression was 20%, 10%, and 10%. A single nerve branch was identified in 7 specimens, and 2 branches were identified in 3 specimens. CONCLUSION: There was at least one case of injury to the saphenous vein and nerve at every level of button insertion at a rate of 10% to 20%. Neurovascular injury may occur despite vigilant use of fluoroscopy and adequate surgical technique. Further investigation into the use of direct medial visualization of these high-risk structures should be done to minimize the risk. Levels of Evidence: Therapeutic, Level II: Prospective, comparative study.

Posterior tibial perforators relationship with superficial nerves and veins: A cadaver study.

BACKGROUND: Most authors have evaluated the location of lower leg arterial perforators, but little is still known about the relationship between the arterial network and great saphenous vein (GSV) and saphenous nerve (SN). The aim of this study is to evaluate the relationship between the arterial network of the posterior tibial artery perforators, the cutaneous nerves, and the superficial venous system in the lower one third of the leg. METHODS: Eighteen lower limbs from cadavers were used for this study. The arterial and venous compartment were selectively injected with a mixture of barium sulfate and epoxy. The specimen were CT scanned and the superficial veins, nerves, and the arterial perforators were dissected. RESULTS: A large perforator of the posterior tibial artery was found at a mean distance of 6.23 cm ± 0.88, with a 95% CI: 5.79-6.67, from the medial malleolus. The average diameter was 0.9 mm ± 0.17, with a 95% CI: 0.81-0.99. In 67% the connection of the venae comitantes to the superficial venous system was established with the GSV, in the other cases, with Leonardo's vein. Both dissection and imaging studies showed perineural interperforator connections along the branches of SN in all the specimens examined. CONCLUSIONS: The distribution pattern of posterior tibial artery perforators followed the superficial nerves in this region. There is an interperforator anastomotic network along the SN. The various patterns of the venous drainage system, in relationship to the distribution of the branches of posterior tibial artery perforators, have been clarified.

Analgesic Effects of GpTx-1, PF-04856264 and CNV1014802 in a Mouse Model of NaV1.7-Mediated Pain.

Loss-of-function mutations of Na(V)1.7 lead to congenital insensitivity to pain, a rare condition resulting in individuals who are otherwise normal except for the inability to sense pain, making pharmacological inhibition of Na(V)1.7 a promising therapeutic strategy for the treatment of pain. We characterized a novel mouse model of Na(V)1.7-mediated pain based on intraplantar injection of the scorpion toxin OD1, which is suitable for rapid in vivo profiling of Na(V)1.7 inhibitors. Intraplantar injection of OD1 caused spontaneous pain behaviors, which were reversed by co-injection with Na(V)1.7 inhibitors and significantly reduced in Na(V)1.7(-/-) mice. To validate the use of the model for profiling Na(V)1.7 inhibitors, we determined the Na(V) selectivity and tested the efficacy of the reported Na(V)1.7 inhibitors GpTx-1, PF-04856264 and CNV1014802 (raxatrigine). GpTx-1 selectively inhibited Na(V)1.7 and was effective when co-administered with OD1, but lacked efficacy when delivered systemically. PF-04856264 state-dependently and selectively inhibited Na(V)1.7 and significantly reduced OD1-induced spontaneous pain when delivered locally and systemically. CNV1014802 state-dependently, but non-selectively, inhibited Na(V) channels and was only effective in the OD1 model when delivered systemically. Our novel model of Na(V)1.7-mediated pain based on intraplantar injection of OD1 is thus suitable for the rapid in vivo characterization of the analgesic efficacy of Na(V)1.7 inhibitors.

Saphenous nerve injury after endovenous laser ablation of incompetent greater saphenous vein: An electroneuromyography study.

AIM: To determine whether endovenous laser ablation of incompetent greater saphenous vein causes a detectable impairment in saphenous nerve conduction. MATERIAL AND METHODS: Thirty-five patients (mean age: 44.78 ± 8.6, male/female ratio: 16/19) who were operated on for incompetent greater saphenous veins, underwent electroneuromyography before and two weeks after the operation. Dysesthesia was questioned as to whether having unpleasant abnormal sensation after the operation. Positive electroneuromyography findings for saphenous nerve injury included a sensory nerve action potential amplitude <2 µV or a nerve conduction velocity <48.0 m/s or a latency onset >5.0 ms. RESULTS: Thirty-four patients were available at two-week follow-up. All patients achieved complete proximal closure. Three patients (8.8%) had dysesthesia at two weeks. Mean electroneuromyography values were not significantly different between preoperative and postoperative period. Postoperatively, none of the patients had abnormal sensory nerve action potential or latency onset, whereas nerve conduction velocity decreased below the lower limit in two patients. These two patients were not among those having dysesthesia and they had no other complaints. CONCLUSION: Injury to saphenous nerve seems not likely during endovenous laser ablation of incompetent greater saphenous veins, as evidenced by normal electroneuromyography values found after the operation.

Myelinated mouse nerves studied by X-ray phase contrast zoom tomography.

We have used X-ray phase contrast tomography to resolve the structure of uncut, entire myelinated optic, saphenous and sciatic mouse nerves. Intrinsic electron density contrast suffices to identify axonal structures. Specific myelin labeling by an osmium tetroxide stain enables distinction between axon and surrounding myelin sheath. Utilization of spherical wave illumination enables zooming capabilities which enable imaging of entire sciatic internodes as well as identification of sub-structures such as nodes of Ranvier and Schmidt-Lanterman incisures.

Axonal morphological changes following impulse activity in mouse peripheral nerve in vivo: the return pathway for sodium ions.

KEY POINTS: Conduction in myelinated axons involves substantial ion movements that must be reversed to restore homeostasis. The pathway taken by sodium ions returning to their original location and the potential osmotic consequences are currently unknown. We report striking morphological changes in axons following sustained impulse conduction that appear to result from osmosis and to indicate accumulation of ions in the periaxonal space followed by their release at the paranode. We conclude that the morphological changes illustrate a hitherto unrecognized part of normal axonal physiology that may also indicate the return pathway for the sodium ions involved in impulse formation. ABSTRACT: Myelinated axons can conduct sustained trains of impulses at high frequency, but this involves substantial ion movements that must be reversed to restore homeostasis. Little attention has been paid to the potential osmotic consequences of the ion movements or to the pathway taken by sodium ions returning to their original endoneurial location, given that the axolemmal Na(+)-K(+)-ATPase extrudes these ions into the periaxonal space beneath the myelin rather than into the endoneurium. Serial confocal imaging of fluorescent axons conducting at sustained physiological frequencies in vivo has revealed surprising morphological changes that may illuminate these problems. Saphenous nerves and spinal roots of anaesthetized transgenic mice expressing axoplasmic yellow fluorescent protein were stimulated electrically or pharmacologically (veratridine). Within 2 h, the axon herniated on one or both sides of the nodal membrane, displacing the paranodal myelin and widening the nodal gap. The herniated axoplasm became directed back towards the internode, forming a 'cap' up to 30 µm long. Concurrently, the fluid in the expanded periaxonal space accumulated into droplets that appeared to travel to the paranode, where they escaped. No such alterations occurred in axons treated with sodium channel or Na(+)-K(+)-ATPase inhibitors. Remarkably, impulse conduction continued throughout, and all these changes reversed spontaneously over hours or days. The morphological changes were verified ultrastructurally, and occurred in virtually all myelinated axons. The findings appear to reveal an overlooked part of the physiological repertoire of nerve fibres, and here they are interpreted in terms of osmotic changes that may illuminate the pathway by which sodium ions return to the endoneurial space after they have entered the axon during impulse conduction.

The impact of direction of great saphenous vein total stripping on saphenous nerve injury.

OBJECTIVES: To examine and compare the effects of downwards versus upwards total stripping of great saphenous vein (GSV) on saphenous nerve (SN) injury using clinical and electrophysiological studies. METHODS: Fifty patients with varicosities were equally and randomly assigned to undergo total, upwards stripping (group A) or downwards stripping (group B) of GSV during saphenectomy. SN function was measured with electroneurogram (ENG) before operation, two weeks and 12 weeks after, in order to record the incidence and type of SN injury. Clinical signs of SN injury were also recorded at the same time points. The results were statistically analysed. RESULTS: There were no statistical significant differences on the occurrence of SN injury between groups A and B at two and 12 weeks, respectively, as confirmed with ENG studies and clinical evaluation. There were no differences between the two techniques with regard to the type of SN injury. SN injury was significantly ameliorated from 34% to 6% during the first three months. CONCLUSION: SN injury was equally observed after downwards or upwards total stripping of the GSV, as confirmed by ENG and clinical evaluation, with no differences in injury type. SN injury tends to be relieved through time in most patients.

Anatomy and embryology of the small saphenous vein: nerve relationships and implications for treatment.

The aim of this paper is to describe the anatomical relations of the small saphenous vein (SSV) in order to define the high-risk zones for the treatment of chronic venous disease. The SSV runs in the saphenous compartment demarcated by two fascia layers: a muscular fascia and a membranous layer of subcutaneous tissue. The clinician should be keenly aware of the anatomical pitfalls related to the close proximity of nerves to the SSV in order to avoid their injury: At the ankle, the origin of the SSV is often plexiform, located deep below the fascia, and the nerve is really stuck to the vein. The apex of the calf is an area of high risk due to the confluence of nerves which perforate the aponeurosis. Moreover, the possible existence of a 'short saphenous artery' which poses a high risk for injection of a sclerosing agent due to a highly variable disposition of this artery surrounding the SSV trunk. For this reason, procedures under echo guidance in this area are mandatory. The popliteal fossa is probably a higher risk zone due to the vicinity of the nerves: the small saphenous arch is close to the tibial nerve, or sometimes the nerve of the medial head of the gastrocnemius muscle. In conclusion, before foam injection or surgery, a triple mapping of the small saphenous territory is mandatory: venous haemodynamical mapping verifying the anatomy that is highly variable, nerve mapping to avoid trauma of the nerves and arterial mapping. This anatomical study will help to define the main high-risk zones.

The course of the distal saphenous nerve: a cadaveric investigation and clinical implications.

INTRODUCTION: Injury to the saphenous nerve at the ankle has been described as a complication resulting from incision and dissection over the distal tibia and medial malleolus. However, the exact course and location of the distal saphenous nerve is not well described in the literature. The purpose of this study was to determine the distal limit of the saphenous nerve and its anatomic relationship to commonly identified orthopaedic landmarks and surgical incisions. METHODS: Sixteen cadaveric ankles were examined at the level of the distal tibia medial malleolus. An incision was made along the medial aspect of the lower extremity from the knee to the hallux to follow the course and branches of the saphenous nerve under direct visualization. We recorded the shortest distance from the most distal visualized portion of the saphenous nerve to the tip of the medial malleolus, to the antero-medial arthroscopic portal site, and to the tibialis anterior tendon. RESULTS: The saphenous nerve runs posterior to the greater saphenous vein in the leg and divides into an anterior and posterior branch approximately 3 cm proximal to the tip of the medial malleolus. These branches terminate in the integument proximal to the tip of the medial malleolus, while the vein continues into the foot. The anterior branch ends at the anterior aspect of the medial malleolus near the posterior edge of the greater saphenous vein. The posterior branch ends near the posterior aspect of the medial malleolus. The average distance from the distal-most visualized aspect of the saphenous nerve to the tip of the medial malleolus measured 8mm +/-; 5mm; from the nerve to the medial arthroscopic portal measured 14mm +/-2mm; and from the nerve to the tibialis anterior measured 16mm +/-3mm. In only one case (of 16) was there an identifiable branch of the saphenous nerve extending to the foot and in this specimen it extended to the first metatarsophalangeal joint. The first metatarsophalangeal joint was innervated by the superficial peroneal nerve in all cases. Small variations were also noted. DISCUSSION AND CONCLUSIONS: This study highlights the proximity of the distal saphenous nerve to common landmarks in orthopaedic surgery. This has important clinical implications in ankle arthroscopy, tarsal tunnel syndrome, fixation of distal tibia medial malleolar fractures, and other procedures centered about the medial malleolus. While the distal course of the saphenous nerve is generally predictable, variations exist and thus the orthopaedic surgeon must operate cautiously to prevent iatrogenic injury. To avoid saphenous nerve injury, incisions should stay distal to the tip of the medial malleolus. The medial arthroscopic portal should be more than one centimeter from the anterior aspect of the medial malleolus which will also avoid the greater saphenous vein. Incision over the anterior tibialis tendon should stay within one centimeter of the medial edge of the tendon.

Relaciones anatómicas de la vena safena magna con el nervio safeno a nivel talocrural / Anatomical relations of the saphenous magna vein with saphenous nerve at the talocrural level

La relación anatómica de la vena safena magna (VSM) y del nervio safeno (NS) en la región talocrural tiene importancia anatomoclínica, sin embargo existen pocos trabajos en la literatura anatómica. Se disecaron 30 pies de cadáveres formolizados de individuos adultos de ambos sexos, describiéndose el origen de la VSM y su relación con el NS en la región talocrural; se midió la distancia entre el NS y la VSM a nivel del ápice, margen anterior y a 1 cm del margen superior del maléolo medial. La VSM se originaba de la unión de la vena marginal medial del pie y el plexo venoso dorsal. La relación anatómica entre la VSM y el NS es variada, cursando el NS en un 63,3 por ciento anterior y 30 por ciento posterior a la VSM y en 6,7 por ciento el NS se dividía en dos ramos los cuales acompañaban anterior y posteriormente a la VSM. La distancia de la VSM y del NS al ápice del maléolo medial fue de 10,75 mm +/- 3,06 y 13,38 +/- 2,82 mm, respectivamente. La distancia de la VSM al margen anterior del maléolo medial fue de 0,53 mm +/- 0,51. Es importante conocer las relaciones de la VSM y del NS para su aplicación clínica, especialmente, en el momento de elegir un acceso venoso periférico no tan frecuente como las venas de la región talocrural.

Despite the clinical and anatomical significance of the anatomical relationship ofthesaphena magna vein (SMV)and thesaphenous nerve in (SN) in the talocrural region there are few studies in the literature. Thirty feet of adult formolized cadavers of both sexes were dissected describing the origin of the SMV and its relation with the SN in the talocrural region. Distance between the SN and the SMV was measured at the apex level, anterior margin and at 1 cm from the upper margin. The SMV originated from the medial marginal vein and dorsal venous arch. Anatomical relation between the SMV and the SN is varied, traveling anterior the SN 63.3 percent, and posterior the SMV 30 percent; in 6.7 percent the SN divided in two branches which joined anterior and posterior to the SMV. The distance of the SMV and the SN medial malleolus apex was 10.75mm +/- 3.06 and 13.38 +/- 2.82 mm. SMV distance to anterior margin of the medial malleolus was 0.53 mm +/- 0.51. The relation between the SMV and SN is important for clinicians particularly at the time of determining peripheral venous access not as frequent in veins of the talocrural region.

The anatomy of the small saphenous vein: fascial and neural relations, saphenofemoral junction, and valves.

PURPOSE: Varicose veins are a frequent burden, also in the small saphenous system. Yet its basic anatomy is not described consistently. We therefore investigated the fascial and neural relationships of the small saphenous vein (SSV) as well as the frequency and position of valves and the different junctional patterns, also considering the thigh extension. MATERIALS AND METHODS: We dissected the legs of 51 cadavers during the regular dissection course held in winter 2007 at Innsbruck Medical University, with a total of 86 SSVs investigable proximally and 94 SSVs distally. RESULTS: A distinct saphenous fascia is present in 93 of 94 cases. It starts with a mean distance of 5.1 cm (SD 1.2 cm) proximal to the calcaneal tuber, where the tributaries to the SSV join to form a common trunk. The neural topography at the level of the gastrocnemius muscle's origins shows the medial sural cutaneous nerve in 88% medially and in 12% laterally to the SSV, the tibial nerve in 64% medially and in 36% laterally, and the common fibular nerve in 98% medially and in 2% laterally to the vein. The saphenopopliteal junction (SPJ) resembled in about 37% type A (UIP-classification), 15% type B, and 24% type C. A total of 17% of specimens showed a venous web or star at the popliteal fossa and 6% had a doubled junction. A thigh extension could be demonstrated in about 84%. A most proximal valve was present in only 94% at a mean distance of 1.2 cm (SD 1.4 cm) to the SSVs orifice. A consecutive distal valve was only present in 65% with a mean distance of 5.1 cm (SD 2.3 cm). CONCLUSION: Two fascial points or regions can be described in the SSVs' course and its own saphenous fascia is demonstrated macroscopically in almost all cases. The neural topography is highly individual. The SPJ is highly individual where we found hitherto unclassified patterns in a remarkable number of veins. Venous valves are not as frequent as we supposed them to be. Furthermore, not all most proximal valves seem to be terminal valves.

Distally based saphenous nerve-great saphenous veno-fasciocutaneous compound flap with nutrient vessels: microdissection and clinical application.

Improvements were made by us in several distally based pedicled flaps of the nutrient vessels of the saphenous nerve with lower rotation points. However, these flaps are still insufficient for trauma complicated by bone defects. Accordingly, we conducted a systematic study of the anatomic theory on distally based pedicled compound flaps of the nutrient vessels of the saphenous nerve and great saphenous vein with 30 lower limbs of adult cadavers injected with red gelatin through the femoral artery. It is found that the nutrient vessels of the saphenous nerve-great saphenous vein consist of arteria saphena, fascial cutaneous branches of the inferior medial genicular artery intermuscular spatium branches of the posterior tibial artery, osteocutaneous perforators, superior ankle perforators, medial anterior malleolus perforators, and fascial perforators of the ankle tunnel region. Musculocutaneous perforators of the interior gastrocnemius muscle also enter the nutrient vessels of cutaneous nerve-superficial vein. From May 2004 to February 2007, 23 cases of skin flaps for treating defective and infectious wound, 10 cases of musculocutaneous flaps for treating ulcus in the lower segment of the leg, medullitis, and exposure of bone, 3 cases for medial calcaneus medullitis, 7 cases of skeletal flaps for treating tibial defects and nonunion of calcaneal bone. In 2-15-month follow-ups all cases presented with survived flaps, and healed surfaces of the wound and the osteomyelitis. For cases of bone nonunion, it showed that the nonunion healed after 18 weeks, with recovery of work ability after year. Three types of the distally based pedicled flaps or compound flaps of vessels of different perforating branches can be designed for repairing tissue defects caused by trauma, such as bone defects in the distal leg, nonunion, large necrotic space as well as traumatic surface of the foot and ankle.

The saphenous vein as a bypass conduit: the potential role of vascular nerves in graft performance.

The saphenous vein is the most commonly used conduit in patients undergoing coronary artery bypass surgery. However, a high proportion of vein grafts occlude within the first year and over 50% patients require further grafting within 10 years. Using conventional harvesting techniques the saphenous vein is damaged due to considerable surgical and mechanical trauma, a situation that affects graft patency. As a superficial vessel located in the leg, the saphenous vein in man is subjected to variations in orthostatic pressure associated with exercise and alterations in posture. These conditions require the vein's calibre to be regulated predominantly by the autonomic nervous system. While posture-induced changes occur in man, and other bipeds, such alterations in pressure may not occur or be more subtle in other species, conditions that may limit the usefulness of various experimental models. The neural control of the saphenous vein is under the influence of a plethora of neurotransmitters and neuropeptides which, apart from affecting vascular tone, possess mitogenic properties that may contribute to morphological changes caused by vascular injury. In addition to their neurotransmitter role a number of factors have a direct action on vascular smooth muscle cells that affects neural blood flow with subsequent influence on peripheral nerve conduction. Such neurovascular actions may potentially play a role in the altered vein reactivity and structure involved in graft failure. In this review we discuss the pressure changes experienced by the saphenous vein, its innervation and use as a bypass graft for revascularization of ischaemic tissue, in particular the myocardium. Also, we consider the value of various common experimental techniques for studying vasoactive and mitogenic factors and their potential role in vein graft performance.

On the sympathetic innervation of the human greater saphenous vein: relevance to clinical practice.

This review focuses on sympathetic perivascular innervation of human saphenous vein. It shows the distribution of the nerves in the vein wall, including an association of the nerves with the vasa vasorum system. An account of a possible contribution of sympathetic nerves to the physiology of the saphenous vein, as well as their relevance to the outcome of coronary artery bypass surgery that uses the vein as a graft, is discussed.

The appropriate length of great saphenous vein stripping should be based on the extent of reflux and not on the intent to avoid saphenous nerve injury.

OBJECTIVE: To investigate the effect of stripping the below knee great saphenous vein (GSV) segment on varicose vein recurrence as well as any disability induced after saphenous nerve injury (SNI) during a 5-year period. METHODS: One hundred and six limbs (86 patients, 64 female, mean age 46 years), that underwent GSV stripping, to the knee or ankle level, were prospectively followed up at 1 month and 5 years postoperatively with clinical examination and color duplex imaging (CDI), in order to evaluate SNI and the development of recurrence. The extent of GSV stripping complied with preoperative CDI in 84 limbs (79%) that were subjected to GSV stripping to the ankle and full abolishment of duplex-confirmed reflux. Furthermore, 19 limbs (18%) underwent stripping restricted to the below knee level since the distal GSV was competent. On the contrary, in three limbs (3%), the extent of stripping did not comply with preoperative CDI due to the absence of varicosities in the tibia, and stripping was restricted to the knee level, although they had reflux along the whole GSV length. RESULTS: Overall recurrence was found in 24 out of 106 operated limbs (23%) after 5 years. Recurrence was found to be 20% (17/84) in the limbs with total GSV stripping and 32% (7/22) in the limbs with restricted GSV stripping (P > .05). However, the recurrence rate in the tibial area was significantly lower in limbs subjected to GSV stripping, which was in compliance with the preoperative CDI (9/103, 9%) compared with those that had undergone GSV stripping that was not in agreement with the preoperative CDI (3/3, 100%; P < .005). Neurological examination at 1 month postoperatively, revealed SNI in 17 limbs (16%). However, at the 5-year neurological reassessment, we found that seven out of these limbs (40%) were alleviated from SNI adverse symptoms presenting only deficits in sensation. In addition, no significance was found concerning SNI between limbs subjected to total and restricted GSV stripping (16/84 vs 1/22; P > .05). CONCLUSIONS: Though SNI may occur after both restricted and total GSV stripping, this does not influence limb disability since any related symptoms seem to regress in almost half of the limbs 5 years postoperatively. Additionally, it seems that recurrence could be reduced in the tibial area if the level of GSV stripping complies with the extent of the ultrosonographically proven GSV reflux. Therefore, the extent of GSV stripping should not be guided by the intent of avoiding SNI.

Myxofibrosarcoma involving the external saphenous nerve: a case report.

Myxofibrosarcoma, also known as "myxoid malignant fibrous histiocytoma" is one of the most common soft tissue sarcomas in the extremities of adult patients. Most cases are characterized by a multinodular and/or infiltrative pattern with a tendency to infiltrate along fascial planes. We report a case of myxofibrosarcoma with an unusual presentation. Despite the clinical impression of a complete surgical resection, microscopic sarcomatous foci extended along the perineurium of the external saphenous nerve proximally up to 20 cm away from the main tumour. This unique case represents an extreme example of the locally agressive behaviour of soft tissue sarcomas and illustrates the microscopic tumour invasion along major nerves.

Free functional muscle transplantation for facial reanimation: experimental comparison between the one- and two-stage approach.

To investigate functional results of either one- or two-staged free muscle transplantation the scutuloauricularis model in the New Zealand white rabbit was used. Thirty rabbits were allocated to two groups with 15 animals each. In Group 1 (one-stage approach) peroneus brevis (PB) was harvested as a free muscle graft with a 7cm long motor branch. The graft was positioned instead of right scutuloauricularis (SCUT) and its vascular supply microsurgically re-established. The motor branch was transferred to the contralateral side and its proximal end coapted to the cut facial motor branch to left SCUT. Before nerve coaptation biopsies were harvested from the cut motor branch for morphological analysis. In Group 2 (two-stage approach) a 7cm long saphenous nerve graft was taken and coapted to the cut motor branch of SCUT and crossed over to the contralateral side. Nerve specimens from the cut motor branch were taken. Eight months later the free transplantation of PB was performed and its motor branch coapted to the distal end of the cross-over nerve graft. After a total time period of 13 months the final experiments were carried out in each group. Maximal tetanic tensions in reinnervated PB were measured and biopsies of muscle grafts together with nerve biopsies from the distal part of the motor branch were harvested for morphological analysis. Muscle grafts of Group 1 revealed tetanic tension values of 12.5N (SD 3.1) in comparison to 10.6N (SD 3.5) obtained in Group 2. This difference was not statistically significant (p=0.303). In Group 1, the amount of regenerated nerve fibers counted at the distal motor branch site (mean: 2798, SD 1242) was significantly higher (p=0.008) than in Group 2 (mean: 1138, SD 1004). Muscle graft morphology revealed significantly less Type I fibers (p=0.016) and more Type IIb/d fibers (p=0.011) in Group 1 compared to Group 2. However, the overall amount of perimysial connective tissue showed no significant difference in both groups (p=0.478). Free muscle transplantation in a one-stage approach offers similar functional results in comparison to the two-stage approach. Although muscle grafts of the one-stage transplantation underwent a longer period of denervation similar contents of perimysial connective tissue could be observed.

Ultrasound observation of the sciatic nerve and its branches at the popliteal fossa: always visible, never seen.

BACKGROUND: In studying patients with sciatic nerve (SN) varices the author found that the sciatic nerve and its major divisions, the tibial and peroneal nerves, could be readily identified on ultrasound imaging of the popliteal fossa. The sciatic nerve lies in the space between the popliteal vein and the small saphenous vein. OBJECTIVES: To confirm that the sciatic nerve can be identified on ultrasonography in patients with venous disease as well as in normal subjects. METHOD: Thirty unselected patients (60 limbs) attending for outpatient consultations were investigated by duplex ultrasound examination of the popliteal fossa. In 10 subjects varicose veins were present, in 20 no varices were visible on clinical examination. RESULTS: The sciatic nerve and its branches where visible and easily recognised in all cases. The sciatic nerve and the small saphenous vein lay in close proximity in cases with of small saphenous vein incompetence. CONCLUSIONS: Ultrasound identification of the sciatic nerve in the popliteal fossa allows assessment of its relationship with the adjacent veins. This technique may be useful in identifying the location of the nerve prior to surgical intervention for varices in the popliteal fossa as well as for endo-luminal occlusion procedures given the close proximity of the vein to the nerve. Sciatic nerve varices, tumours, extrinsic dislocation and nerve lesions may also be detected.