The consistent presence of the human accessory deep peroneal nerve

Twenty-four human legs were dissected macroscopically to study the morphological details of the accessory deep peroneal nerve. This nerve arose from the superficial peroneal nerve and descended in the lateral compartment of the leg, deep to peroneus longus along the posterior border of peroneus brevis. Approaching the ankle joint, this nerve passed through the peroneal tunnels to wind around the lateral malleolus; it then crossed beneath the peroneus brevis tendon anteriorly to reach the dorsum of the foot. The accessory deep peroneal nerve was found in every case examined and constantly gave off muscular branches to peroneus brevis and sensory branches to the ankle region. In addition, this nerve occasionally had muscular branches to peroneus longus and extensor digitorum brevis, and sensory branches to the fibula and the foot. The anomalous muscles around the lateral malleolus were also innervated by this nerve. Neither cutaneous branches nor communicating branches with other nerves were found. The present study reveals that the accessory deep peroneal nerve is consistently present and possesses a proper motor and sensory distribution in the lateral region of the leg and ankle. It is not an anomalous nerve as has previously been suggested.     

腓骨短肌肌瓣的血供研究与临床应用

目的 了解腓骨短肌血供的解剖学特征,探讨临床应用腓骨短肌肌瓣和以腓骨短肌为蒂的组织瓣内移修复踝周软组织缺损或治疗胫骨骨不连的可行性。 方法 30例经10%福尔马林固定的成人下肢标本,动脉灌注红色乳胶,解剖观察腓骨短肌的血管来源、走行及分布情况;临床上设计切口取腓动脉的弓形动脉分支为蒂,修复踝周软组织缺损和胫骨骨不连患者10例。 结果 腓骨短肌血管呈节段性分布,主要来自腓动脉的弓形动脉,最远侧的分支平均位于外踝上(50.81±5.45) mm;根据腓骨短肌及血供特点,临床设计的腓骨短肌肌瓣应用于10例患者,均获成功。 结论 腓骨短肌血供丰富,逆行腓骨短肌肌瓣血供可靠,是修复踝周软组织缺损和胫骨骨不连的一种理想肌瓣。     

Accessory peroneal nerves in the human

The Nervus peroneus profundus accessorius was described by Ruge (1878) in the lower mammals and for the first time identified by Bryce (1897) in man. It is an accessory terminal branch of the superficial peroneal (musculocutaneous) nerve which winds round the lateral malleolus beneath the tendons of the peronei muscles and reaches the dorsum of the foot; there it often supplies the lateral portion of the extensor digitorum brevis muscle. In further investigations this nerve has been traced in 21.2% of subjects resp. in 13.5% of legs. This nerve, however, is not the only accessory branch of the common peroneal nerve: In 14 out of 140 subjects (10%) resp. in 22 out of 280 legs (7.9%) a Nervus peroneus superficialis accessorius has been found. This nerve pierces the anterior crural intermuscular septum either in common with deep peroneal (anterior tibial) nerve or at a lower point. Then it descends in front of the septum rarely giving off muscular branches to the extensor digitorum longus and peroneus tertius muscles; in the lower half of the leg it pierces the crural fascia, passes in front of the ankle joint and becomes the medial cutaneous nerve of the dorsum of the foot. This accessory superficial peroneal nerve may be of importance in surgery of the leg and foot.     

Longitudinal Split of the Peroneus Brevis Tendon and Lateral Ankle Instability: Treatment of Concomitant Lesions

OBJECTIVE: To describe the clinical picture, pathophysiology, and treatment of concomitant lesions of the peroneus brevis tendon and lateral ligament injuries to the ankle. BACKGROUND: In some cases, chronic lateral ankle instability is associated with a longitudinal partial tear in the peroneus brevis tendon. Patients who suffer from this lesion usually have atypical posterolateral ankle pain combined with signs of recurrent ligament instability ("giving way"). The tendon injury is often overlooked because it is combined with the ligament injury, and the injury mechanisms are similar. DESCRIPTION: Tears or laxity in the superior peroneal retinaculum allow the anterior part of the injured peroneus brevis tendon to ride over the sharp posterior edge of the fibula, leading to a longitudinal tear in the tendon. This combined injury should be suspected in patients with recurrent giving way of the ankle joint and retromalleolar pain. The diagnosis can be established using either ultrasonography or magnetic resonance imaging. DIFFERENTIAL DIAGNOSIS: Ligament injury, tenosynovitis, peroneus longus tendon lesion, os peroneum fracture, distal peroneus brevis tendon tear, or anomalous peroneus tertius tendon. TREATMENT: The tendon injury and the ligament insufficiency should be repaired at the same time. CONCLUSIONS: We recommend reconstruction of the superior peroneal retinaculum, combined with repair of the tendon, using side-to-side sutures and anatomical reconstruction of the lateral ankle ligaments.     

Electromechanical assessment of ankle stability

The goal of this study was to approach ankle instability by measuring the electromechanical delay of the peroneal muscles (foot pronators). For that purpose, supramaximal electrical stimulation of common peroneal nerve was applied when the subject was standing on a force plate in bipedal stance or monopedal stance, postures requiring greater ankle stabilization. The electromechanical delay (EMD) was defined as the time interval between the onset of the peroneus longus (PL) electromyogram detected by surface electrodes and the onset of the lateral ground reaction force (Fy) measured on a force plate. Ten healthy subjects (control group, C-G) and ten subjects with functional ankle instability ("FAI" group, FAI-G) performed the tests. In C-G, the mean EMD values decreased significantly (P<0.001) from the bipedal [10.54 (0.71) ms; mean (SD)] to the monopedal stance [8.67 (0.63 ms)]. Since a monopedal stance is known to require higher leg muscle tone resulting in a higher ankle stiffness, these results indicate that PL EMDs are sensitive to musculo-tendinous stiffness. They validate the choice of a PL EMD measurement as an indirect index of musculo-tendinous stiffness at the ankle. In both bipedal and monopedal stance conditions, EMD values were significantly higher in FAI subjects. They ranged from 12.64 (1.14) ms in the bipedal stance to 10.85 (1.07) ms in the monopedal stance. This suggests a lower musculo-tendinous stiffness at the ankle, which may contribute to the ankle instability. Electronic Publication     

Unique distribution by the peroneal nerves: a case report

Purpose

Among the branches of common peroneal nerve, the superficial peroneal provides cutaneous innervation to major part of the dorsum of the foot and deep peroneal nerve supplies the skin over the first interdigital cleft region.

Methods

The present rare case was observed during routine dissection of leg for undergraduate students, in a 52-year-old male, formalin fixed cadaver.

Results

The superficial peroneal nerve provided solely motor branches to peroneus longus and brevis, whereas cutaneous branches were provided by deep peroneal nerve. In the lower one-third of the leg deep peroneal nerve divided into medial and lateral branches. The medial branch supplied tibialis anterior and the lateral branch supplied skin of medial three and half toes. Moreover, the sural nerve supplied the skin of lateral one and a half toes.

Conclusion

Awareness of this type of variations in the course of nerves helps to alert the surgeons when there are complaints of atypical or unique pain in that particular region.     

Anatomic bases of ankle arthroscopy: study of superficial and deep peroneal nerves around anterolateral and anterocentral approach

We studied the anatomy of the anterolateral and anterocentral portal sites for ankle arthroscopy with reference to the superficial peroneal nerve (SPN) in 29 cadavers (51 ankles) and the deep peroneal nerve (DPN) in 11 cadavers (21 ankles). In relation to the level of division into the medial and intermediate cutaneous nerves and their terminal branches, we classified the structure of the SPN surrounding the ankle into five types. We also identified the point where the SPN and the DPN cross the level of the talocrural joint. 32% of specimens had different SPN division types on the two sides and there was an average of 2 nerves at the level of the talocrural joint. Branches of the SPN were found lateral to the edge of the peroneus tertius tendon in 11.8% of specimens, and at its lateral edge in 27.5%. The DPN and some branches of the SPN were positioned around the lateral edge of the extensor hallucis longus tendon. We consider that the anterolateral portal should be made at least 2 mm lateral to the peroneus tertius tendon to avoid injury to the SPN, since the diameter of the scope is 2.7 mm. The anterocentral portal is unsuitable for arthroscopy due to a high risk of injury to the DPN and branches of the SPN.     

Arterial supply of the soleus muscle: anatomical study of fifty lower limbs

Soft tissue defects of the lower limb are a formidable challenge to the plastic surgeon but a soleus muscle flap often provides the solution. Various types of soleus muscle flap have been described, based mainly on the vascular supply. The arterial blood supply of the soleus muscle was studied in 50 cadaveric lower limbs. The blood vessels and their branches to the muscle were dissected. The distance of the origin of the perforators was measured from fixed bony landmarks. Branches of the popliteal artery trunk, the posterior tibial artery, and the peroneal artery supplied the soleus muscle. The number of branches to the soleus muscle from these main arteries were analyzed. The medial part of the muscle was supplied throughout its length by perforators arising from the posterior tibial artery. This constant feature makes the medial part of the muscle reliable as a proximally or distally based flap. The average distances of the lower perforators arising from the posterior tibial artery were 6.5 cm, 11.6 cm, and 16.8 cm from the medial malleolus. The branches of the peroneal artery were mostly distributed in the upper half of the muscle. These large pedicles allow a composite transfer of the soleus muscle with the fibula. Lower perforators were demonstrated to arise from the peroneal artery in 60% of the limbs but the scarcity of perforators in this region limits the clinical usefulness of an inferiorly based lateral hemisoleus flap. The study demonstrates the distribution of arteries entering the soleus muscle and how the information may be used in the design of soleus muscle flaps. The average numbers of the perforators arising from the vessels and their distribution have been highlighted.     

腓总神经压迫综合征的解剖学研究

在62侧成人下肢标本上观察了腓总神经穿行的腘窝外侧沟和腓骨长肌纤维拱的形态。拱的入口在腓骨头尘下方1.8cm,拱长2.4cm,属全腱性的拱仅占8.1％。对腓总神经的主要分支部位作了测量,这些数据对腓总神经压迫综合征的诊断和治疗有参考意义。     

Surgical anatomy of the lateral supramalleolar flap in arteritic patients: an anatomic study of 24 amputation specimens

The lateral supramalleolar flap (LSMF) is frequently used for covering major tissue defects of the foot and ankle but usually, in case of arteriopathy of the lower limbs, this device is contra-indicated. Twenty-four specimens of amputated limbs of patients suffering from arteriopathy of the lower limbs allowed us to study the vascular anatomy of this flap after intra-arterial injection of colored latex. At the time of the amputation the average age of the patients was 68.5 years. The clinical signs of arteriopathy had been present for 3-16 years. In 10 cases the amputation was performed directly, in 14 cases after an unsuccessful attempt at revascularization. The dissection results revealed certain specificities in the vascularization of the LSMF with arteriopathy. The perforating branch of the peroneal artery was found in all cases. The descending branch of this perforating artery was found to be patent in 22 cases but slim in five cases. It was absent in two cases. The superficial peroneal nerve and its vascular network always participated in the vascularization of the flap. Thus, its preservation in the distal part of the flap offers a second vascular flow to the pedicle of the LSMF. This specificity increases the theoretical feasibility of the LSMF from 17 to 22 cases out of 24 in our dissections. The authors suggest a theory according to which the evolution of arteriopathy and the gradual concomitant development of a supply network, which effects the vascularization of the sensory nerves too, induces the "anticipation" of a flap. The preliminary distal revascularization by bypass grafts or by some kind of endovascular treatment should guarantee the good vascularization of a limb and the reliable use of this neurocutaneous arterial network.     

逆行腓骨肌肌皮瓣设计的解剖学研究

目的　为逆行腓骨肌皮瓣的设计与临床应用提供解剖学依据。 方法 新鲜下肢标本20侧,动脉灌注红色乳胶,解剖观测腓动脉、腓骨长肌、腓骨短肌及其表面皮肤与营养血管的的起始、走行、分支、分布的情况;新鲜标本2具,动脉灌注乳胶、氧化铅混悬液,CT扫描后三维重建小腿与足部血管。 结果 腓动脉起始外径(3.7±0.7) mm,多条分支供给比目鱼肌、 长屈肌、腓骨长、短肌及表面皮肤。腓动脉穿支的血管蒂可游离长度为(3.5±1.3) cm。腓动脉终末穿支在胫腓骨骨间膜中穿出,外径(1.2±0.4)mm,分为升支和降支。腓骨短肌肌腹的上部有一支较粗的腓浅动脉发自胫前动脉,向前穿骨间膜行于腓骨长肌与小腿前群肌之间,管径(1.8±0.5) mm,行向下营养腓骨短肌、腓浅神经和小腿前外侧部皮肤。 结论 以腓动脉中、下部穿支或终末穿支与其它血管的吻合部为蒂,可以设计切取逆行腓骨长、短肌肌皮瓣,修复小腿下部及足背部软组织缺损。     

老年人手提重物时不同停止方式对步态稳定性的影响

目的 分析老年人手提重物及不同步态停止方式时下肢肌肉活动特性及相应关节运动参数的变化,探究手部负重及步态停止方式对老年人步态稳定性以及身体平衡的影响.方法 以0 kg、双手各2.5 kg和右手5 kg的负重方式,分别在急停和有计划停止条件下,采集双侧下肢踝、膝、髋关节角度以及表面肌电信号.结果 在不同的负重方式下,双侧...     

Anatomical basis of compression of common peroneal nerve

A thickened fascia on the lateral border of fibula between soleus and peroneus longus is described. In 8.5% of cases, the fascia over the common peroneal nerve which is continuous with the fascia extending between soleus and peroneus longus is comparatively thick. It is suggested that in certain cases of muscular contractions this thickened fascia may be a causative factor involved in the compression of common peroneal nerve, since this fascia is also continuous with the fascia over the surrounding muscles.     

Central representation of the hindlimb muscles supplied by the common peroneal nerve. A retrograde horseradish peroxidase study in the dog

Motoneurons supplying the common peroneal nerve in the dog were identified by the retrograde horseradish peroxidase method. They were distributed within two discrete cell columns (columns 2 and 2') in the 6th and 7th lumbar segments. The extensor digitorum longus muscle was represented in the dorsolateral part of column 2; the peroneus longus muscle in the ventrolateral part and the tibialis cranialis muscle in the intermediate lateral part. The medial half of column 2 contained motoneurons supplying the superficial peroneal nerve. Column 2', which was situated dorsomedially to column 2, contained motoneurons innervating the extensor digitorum brevis muscle.     

Proprioceptive population coding of two-dimensional limb movements in humans: I. Muscle spindle feedback during spatially oriented movements

The proprioceptive coding of multidirectional ankle joint movements was investigated, focusing in particular on the question as to how accurately the direction of a movement is encoded when all the proprioceptive information from all the muscles involved in the actual movement is taken into account. During ankle movements imposed on human subjects, the activity of 30 muscle spindle afferents originating in the extensor digitorum longus, tibialis anterior, extensor hallucis longus and peroneus lateralis muscles was recorded from the lateral peroneal nerve using the microneurographic technique. In the first part of the study, it was proposed to investigate whether muscle spindle afferents have a preferred direction, as previously found to occur in the case of cortical cells, and to analyze the neural coding of the movement trajectories using a "population vector model." This model is based on the idea that neuronal coding can be analyzed in terms of a series of vectors, each based on specific movement parameters. In the present case, each vector gives the mean contribution of a population of muscle spindle afferents within one directionally tuned muscle. A given population vector points in the "preferred sensory direction" of the muscle to which it corresponds, and its length is the mean frequency of all the afferents within that muscle. Our working hypothesis was that the sum of these weighted vectors points in the same direction as the ongoing movement. The results show that each muscle spindle afferent, and likewise each muscle, has a specific preferred sensory direction, as well as a preferred sensory sector within which it is capable of sending sensory information to the central nervous system. Interestingly, the results also demonstrate that the preferred directions are the same as the directions of vibration-induced illusions. In addition, the results show that the neuronal population vector model describes the multipopulation proprioceptive coding of spatially oriented 2D limb movements, even at the peripheral sensory level, based on the sum vectors calculated from all the muscles involved in the movement. In an accompanying paper, the coding of more complex 2D movements such as those involved in drawing rectilinear and curvilinear geometrical shapes was investigated.     

Pattern of monosynaptic heteronymous Ia connections in the human lower limb

Changes in the firing probability of single motor units in response to electrical stimulation of muscle nerves were used to derive the projections of muscle spindle Ia afferents to the motoneurones of various leg and thigh muscles. Discharges of units in soleus, gastrocnemius medialis, peroneus brevis, tibialis anterior, quadriceps, biceps femoris and semitendinosus were investigated after stimulation of inferior soleus, gastrocnemius medialis, superficial peroneal, deep peroneal and femoral nerves. Homonymous facilitation, occurring at the same latency as the H reflex and therefore attributed to monosynaptic Ia EPSPs, was found in virtually all the sampled units. In many motor nuclei an early facilitation was also evoked by heteronymous low-threshold afferents. The heteronymous facilitation was considered to be mediated through a monosynaptic pathway when the difference between the central latencies of heteronymous and homonymous peaks was not more than 0.2 ms. The heteronymous Ia connections were widely distributed. In particular, monosynaptic coupling between muscles operating at different joints appears to be the rule in humans, though it is rare between ankle and knee muscles in the cat and the baboon.     

踝关节外侧韧带和距下关节韧带修复重建的应用解剖

目的 :为踝关节外侧韧带和距下关节韧带损伤修复重建提供解剖学基础。方法 :在 3 2侧经防腐固定、8侧冷藏新鲜标本上解剖观测踝关节外侧韧带和距下关节韧带及小趾趾长伸肌腱、第 3腓骨肌腱、腓骨短肌腱、伸肌下支持带 ,在新鲜标本上摹拟修复术。结果 :小趾趾长伸肌腱、第 3腓骨肌腱、腓骨短肌腱、伸肌下支持带解剖位置恒定 ,与踝关节外侧韧带和距下关节韧带相毗邻 ,具有一定的长、宽、厚度 ,可形成移植供体。结论 :①陈旧性踝关节外侧韧带和距下关节韧带的损伤 ,原位修复较难 ,用肌腱转位修复是一种可行的方法 ;②可用腓骨短肌腱修复距腓前和跟腓韧带损伤 ,小趾趾长伸肌腱和第 3腓骨肌腱转位修复距下关节韧带 ,伸肌下支持带可用作加强缝合 ,术式经标本摹拟具有可行性。     

Proprioceptive population coding of limb position in humans

The present study investigates the coding of positions reached in a two-dimensional space by populations of muscle spindle afferents. The unitary activity of 35 primary muscle spindle afferents originating from the tibialis anterior, extensor digitorum longus, extensor hallucis longus, and peroneus lateralis muscles were recorded from the common peroneal nerve by the microneurographic technique. The steady mean frequency of discharge was analyzed during 16 passively maintained positions of the tip of the foot. These positions were equally distant from and circularly arranged around the "neutral" position of the ankle. The results showed that a same position of the foot was differently coded depending on whether it was maintained for several seconds or whether it was attained after a movement. Muscle spindle activity was increased or decreased, respectively, when the previous movement lengthened or shortened the parent muscle; the magnitude of change in activity depended on the amount of lengthening or shortening in relation to movement direction. Each muscle surrounding the ankle joint was shown to encode the different spatial positions following a directional tuning curve. Data were analyzed by using the "neuronal population vector model". This model consists of calculating population vectors representing the mean contribution of each muscle population of afferents to the coding of a particular position, and by finally calculating a sum vector. The direction of the sum vector was shown to accurately describe the direction of a given maintained position compared to the initial position. We conclude that muscle spindle position coding is based on afferent information coming from the whole set of muscles crossing a given joint. A given spatial position is associated with a stable muscle afferent inflow where each muscle makes an oriented and weighted contribution to its coding. Electronic Publication     

Septocutaneous perforators of the peroneal artery relative to the fibula: anatomical basis of the use of pedicled fasciocutaneous flap

There are many studies describing the perforating branches of the peroneal artery but none of them identifies their locations relative to fibula. The aim of this study was to demonstrate the locations of the perforators relative to the fibula and to present a case, treated with an adipofascial flap, based on one of these small arteries. In this study, nine fresh male cadavers’ legs injected with colored latex were dissected for demonstration of the longitudinal axis of these perforators. A large incision was made on the lateral part of the leg from the head of the fibula to the ankle. The peroneal perforating vessels were displayed. The posterior margin of the fibula was marked with needles from proximal to distal just above every perforator. The distance between the needle and the perforator was recorded. Their diameters were measured at the level of fascial emergence. There were four to seven perforating vessels; the larger vessels were near the proximal end of the fibula with an average of 1.1 mm and a minimum of 0.8 mm. We found that these branches were not parallel to fibula, but aligned in an oblique projection from posterior to anterior and from distal to proximal because of the course of the intermuscular septum between the soleus and peroneus longus muscles. The lowermost vessel was 1.7 cm away from the posterior margin of the fibula while the uppermost vessel was 0.25 cm away from the posterior ridge of the fibula. Adipofascial or fasciocutaneous flaps, which have important advantages in covering small to medium sized defects, can be based on the perforators of the peroneal artery. But for the centralization of the flap pedicle, the locations of the perforators, which are aligned from the lateral malleolus to the fibular head in oblique direction and from the posterior to the anterior must be taken into consideration. This knowledge is crucial for the flap design and the centralization of the vessels.