Ultrahigh-frequency ultrasound of fascicles in the common fibular, superficial fibular, and sural nerves.

INTRODUCTION/AIMS: While ultrasound assessment of cross-sectional area and echogenicity has gained popularity as a biomarker for various neuropathies, there is a scarcity of data regarding fascicle count and density in neuropathies or even healthy controls. The aim of this study was to determine whether fascicles within select lower limb nerves (common fibular, superficial fibular, and sural nerves) can be counted in healthy individuals using ultrahigh-frequency ultrasound (UHFUS). METHODS: Twenty healthy volunteers underwent sonographic examination of the common fibular, superficial fibular, and sural nerves on each lower limb using UHFUS with a 48 MHz linear transducer. Fascicle counts and density in each examined nerve were determined by a single rater. RESULTS: The mean fascicle number for each of the measured nerves included the following: common fibular nerve 9.85 (SD 2.29), superficial fibular nerve 5.35 (SD 1.59), and sural nerve 6.73 (SD 1.91). Multivariate linear regression analysis revealed a significant association between cross-sectional area and fascicle count for all three nerves. In addition, there was a significant association seen in the common fibular nerve between fascicle density and height, weight, and body mass index. Age and sex did not predict fascicle count or density (all p > .13). DISCUSSION: UHFUS enabled the identification and counting of fascicles and fascicle density in the common fibular, superficial fibular, and sural nerves. Knowledge about normal values and normal peripheral nerve architecture is needed in order to further understand and identify pathological changes that may occur within each nerve in different disease states.

Unusual entrapment symptomatology treated in 115 cases by neurolysis of the common fibular nerve at the fibular head combined with neurolysis of the posterior tibial nerve at the tarsal tunnel.

INTRODUCTION: Entrapment of the common fibular nerve (CFN) at the head of the fibula and entrapment of the posterior tibial nerve (PTN) at the tarsal tunnel are the most common nerve entrapment syndromes in the lower limb. Our aim was to study the results of combined neurolysis of the CFN and PTN for chronic lower limb pain. We hypothesized that combined neurolysis allowed a reduction of this chronic pain. MATERIAL AND METHOD: This bi-centric retrospective study took place from January 2015 to November 2018, with a single senior surgeon. The inclusion criteria were all patients operated on for an idiopathic entrapment syndrome with neurolysis of the PTN at the tarsal tunnel, combined with neurolysis of the CFN at the head of the fibula. The primary endpoint was the pain evolution assessed on a numerical analogue scale (NAS) preoperatively and postoperatively on D+21, and at the last follow-up. The secondary endpoint was to determine the prognostic factors on the clinical outcome of neurolysis. RESULTS: One hundred and fifteen neurolysis were included, comprising 64 women and 38 men with a mean age of 57±17.6 years. The preoperative pain (NAS0) was evaluated at 6±2.4 points. At D+21 postoperatively, there was a significant reduction in pain (NASD+21: 3±2.6 points, p<0.01). Similarly, at the last follow-up (with a mean follow-up of 37±8.4 months), there was a significant reduction in pain (NASLFU: 2±2.5, p<0.01). A history of systemic inflammatory disease was the only factor associated with a less significant decrease in pain at D+21, according to a multivariate analysis (p<0.01). There were 14 complications (12%) not requiring revision surgery. CONCLUSION: This study is the first to demonstrate the efficacy of combined neurolysis of the CFN at the head of the fibula and the PTN at the tarsal tunnel, in the treatment of idiopathic nerve entrapment syndrome of the lower limb. LEVEL OF EVIDENCE: IV; Retrospective comparative study.

Role of electromyography and ultrasonography in the diagnosis of double crush lumbar radiculopathy and common fibular injury: illustrative cases.

BACKGROUND: Double crush syndrome consists of two compression sites along a peripheral nerve and is rare in the lower extremities. Electrodiagnostic and ultrasound (US) studies may be helpful in evaluating foot drop involving overlapping pathologies. OBSERVATIONS: Case 1 involved a man who presented with left dorsiflexor weakness and left foot numbness. Electromyography (EMG) revealed a left common fibular nerve entrapment neuropathy and left L5 radiculopathy. US and magnetic resonance imaging (MRI) revealed a large cystic lesion of the left common fibular nerve treated by cyst removal. The left foot drop persisted postoperatively. Lumbar computed tomography myelography revealed severe left foraminal stenosis at L5-S1. Multilevel lumbar laminectomies and facetectomies with an L5-S1 fusion were performed. Within 1 month postoperatively, the left foot drop had improved. Case 2 involved a man who developed a right foot drop caused by right lumbar foraminal stenosis at L4-5 and L5-S1. EMG and US of the right common fibular neuropathy showed large fascicles involving the right common fibular nerve. MRI revealed a hyperintense signal of the right common fibular nerve. Spontaneous improvement occurred within 6 months without surgery. LESSONS: Spine surgeons should recognize double crush in the lower extremities. EMG and US are valuable in detecting peripheral nerve abnormalities, especially in cases with overlapping lumbar pathology.

Defects of the sciatic nerve and its divisions treated by direct suturing in 90 degrees knee flexion: report on the first clinical series.

OBJECTIVE: To evaluate functional results after treatment of large defects of the sciatic nerve and its divisions by direct nerve suturing in high knee flexion. METHODS: A retrospective review was conducted in patients treated for lower extremity nerve defects between 2011 and 2019. Inclusion criteria were a defect > 2 cm with a minimal follow-up period of 2 years for the sciatic nerve and 1 year for its divisions. Nerve defects were bridged by an end-to-end suture with the knee flexed at 90° for 6 weeks. Functional results were assessed based on the Medical Research Council's grading system. RESULTS: Seventeen patients with a mean age of 27.6 years were included. They presented with seven sciatic nerve defects and ten division defects, including eight missile injuries. The mean time to surgery was 12.3 weeks and the mean nerve defect length was 5 cm. Overall, 21 nerve sutures were performed, with eight in the tibial distribution and 13 in the fibular distribution. Post-operatively, there was no significant knee stiffness related to the immobilization. The mean follow-up time was 24.5 months. Meaningful motor and sensory recovery were observed after 7 of 8 sutures in the tibial distribution and 11 of 13 sutures in the fibular distribution. A functional sural triceps muscle with protective sensibility of the sole was restored in all patients. There were no differences according to the injury mechanisms. CONCLUSION: Temporary knee flexion at 90° allows for direct coaptation of sciatic nerve defects up to 8 cm, with promising results no matter the level or mechanism of injury.

Common fibular nerve palsy due to fabella compression: An illustrative case report.

BACKGROUND: The fabella is a sesamoid bone situated in the tendon of the lateral head of the gastrocnemius muscle behind the lateral femoral condyle. Common fibular nerve injury may occur anywhere on its course and the most common etiology remains compression at the level of the head of the fibula. Compression by a fabella is a very unusual cause of common fibular nerve palsy and only few case reports are described in the literature. We present here an illustrative case. CASE DESCRIPTION: A 50-year-old female patient presented with a left drop-foot evolving for two weeks without pain or sensory deficit. Clinical examination revealed a paresis of the left foot dorsiflexors muscles (3/5). A compressive neuropathy of the common fibular nerve at the level of the fibula head was demonstrated by nerve conduction studies. Ultrasound of the left knee revealed nerve compression by a fabella. Early decompressive surgery was performed and the fabella was excised. We noticed an almost complete recovery probably due to early treatment (4+/5 two months after surgery). CONCLUSIONS: Common fibular nerve palsy related to fabella compression is very uncommon. Good clinical outcome has been described at 1-2 years with an early work-up and a prompt surgical decompression.

Previously Unreported Sciatic Nerve Variation: Case Report.

The sciatic nerve typically follows its course through the greater sciatic foramen, below the piriformis muscle, and down the posterior aspect of the thigh, but many anatomical variations exist. Herein, we report an unusual relationship between the sciatic nerve and piriformis muscle in which the split common fibular nerve went through the piriformis and had a variant communication with the tibial nerve. To our knowledge, this anatomical variation has not been previously reported. Such variants are important to fully understand pathologies involving the sciatic nerve.

Single versus double tendon transfer for foot drop due to post-traumatic common fibular nerve palsy.

PURPOSE: To compare functional outcomes of single versus double tendon transfer for foot drop correction and toe drop prevention in posttraumatic common fibular nerve palsy. METHODS: A retrospective study was conducted on data from patients with posttraumatic common fibular nerve palsy treated by tendon transfer between 2001 and 2018. In cases of single tendon transfer (STT) the tibialis posterior (TP) tendon was transferred anteriorly through the interosseous membrane to a new insertion on the lateral cuneiform. In cases of double tendon transfer (DTT), the same TP tendon transfer was combined with a transfer of the flexor digitorum longus to the extensor digitorum longus and extensor hallucis longus tendons. Functional assessment was based on the Carayon score to evaluate foot drop correction and on the Yeganeh score to evaluate toe drop prevention. RESULTS: A total of 27 patients were included: 13 in the STT group and 14 in the DTT group. Functional results were comparable between groups in terms of reduction of foot drop, active range of ankle motion and Carayon score. Prevention of toe drop, active toe extension and Yeganeh score were significantly greater in the DTT group, however, active toe extension of was only restored in only 8 cases in the DTT group. CONCLUSIONS: Double transfer of TP and FDL tendons is a reliable method to restore balanced ankle dorsiflexion and prevent toe drop. However, recovery of active toe extension was inconsistent and Carayon scores were not superior to those obtained with a single TP tendon transfer.

Varied Presentation and Importance of MR Neurography of the Common Fibular Nerve in Slimmer's Paralysis.

Slimmer's paralysis refers to a common fibular nerve palsy caused by significant and rapid weight loss. This condition usually results from entrapment of the common fibular nerve due to loss of the fat pad surrounding the fibular head. Several etiologies of common fibular nerve palsy have been proposed, including trauma, surgical complications, improperly fitted casts or braces, tumors and cysts, metabolic syndromes, and positional factors. We present 5 cases of slimmer's paralysis in patients who had lost 32-57 kg in approximately 1 year. In 2 cases, MR neurogram of the knee demonstrated abnormalities of the common fibular nerve at the fibular head. Two patients underwent a common fibular nerve decompression at the fibular head and attained improved gait and sensorimotor function. Weight loss, diabetes mellitus, and immobilization may have contributed to slimmer's paralysis in 1 case. Awareness of slimmer's paralysis in patients who have lost a significant amount of weight in a short period of time is imperative to detect and treat a fibular nerve neuropathy that may ensue.

The most commonly injured nerves at surgery: A comprehensive review.

Iatrogenic nerve injury during surgery is a major source of concern for both patients and surgeons. This study aimed to identify the nerves most commonly injured during surgery, along with the commonly associated operative procedures. A literature search was conducted using the PubMed database to identify nerves commonly injured during surgery, along with the surgical procedure associated with the injury. The following 11 nerves, ranked in order with their associated surgical procedures, were found to be the most commonly injured: (a) intercostobrachial nerve in axillary lymph node dissections and transaxillary breast augmentations, (b) vestibulocochlear nerve in cerebellopontine tumor resections and vestibular schwannoma removals, c) facial nerve in surgeries of the inner ear and cheek region, (d) long thoracic nerve in axillary lymph node dissections, (e) spinal accessory nerve in surgeries of the posterior triangle of the neck and cervical lymph node biopsies, (f) recurrent laryngeal nerve in thyroid surgeries, (g) genitofemoral nerve in inguinal hernia and varicocele surgeries, (h) sciatic nerve in acetabular fracture repairs and osteotomies, (i) median nerve in carpal tunnel release surgeries, (j) common fibular nerve in varicose vein and short saphenous vein surgeries, and (k) ulnar nerve in supracondylar fracture surgeries. Although the root cause of iatrogenic nerve injury differs for each nerve, there are four unifying factors that could potentially decrease this risk for all peripheral nerves. These four influencing factors include knowledge of potential anatomical variations, visual identification of at-risk nerves during the procedure, intraoperative nerve monitoring, and expertise of the surgeon.

Fibular Nerve Repair by Lateral Sural Cutaneous Nerve Graft: Anatomic Feasibility Study and Clinical Results.

OBJECTIVE: The common fibular nerve (CFN) is the most frequently injured nerve in the lower limbs. Surgical management is necessary in approximately two thirds of patients and includes neurolysis, suture, graft repair, or nerve transfer. The distal sural nerve is the preferred donor for grafting, but it is not without complications and requires a second incision. We sought to study the surgical anatomy of the lateral sural cutaneous nerve (LSCN) with the aim of repairing CFN injuries through the same incision and as a potential source for grafting in other nerve injuries. METHODS: The popliteal fossa was dissected in 11 lower limbs of embalmed cadavers to study LSCN variations. Four patients with CFN injuries then underwent surgical repair by LSCN grafting using the same surgical approach. RESULTS: At the medial margin of the biceps femoris, the LSCN emerged from the CFN approximately 8.15 cm above the fibular head. The LSCN ran longitudinally to the long axis of the popliteal fossa, with an average of 3.2 cm medial to the fibular head. The mean LSCN length and diameter were 9.61 cm and 3.6 mm, respectively. The LSCN could be harvested in all patients for grafting. The mean graft length was 4.4 cm. Motor function was consistently recovered for foot eversion but was recovered to a lesser extent for dorsiflexion and toe extension. All patients recovered sensitive function (75% of S3). Hypoesthesia was recognized at the calf. CONCLUSIONS: LSCN harvest is a viable alternative for nerve grafting, especially for repairing short CFN injuries, thereby avoiding the need for a second incision.

A simple test to assist with the diagnosis of common fibular nerve entrapment and predict outcomes of surgical decompression.

BACKGROUND: Common fibular (peroneal) nerve (CFN) entrapment is the most frequent nerve entrapment in the lower extremity. It can cause pain, sensory abnormalities, and reduced ability to dorsiflex the foot or a drop foot. A simple test to assist with diagnosis of CFN entrapment is described as an adjunctive clinical tool for the diagnosis of CFN entrapment and also as a predictor of successful surgical decompression of a CFN entrapment. METHODS: The test, a lidocaine injection into the peroneus longus muscle at the site of a common fibular nerve entrapment, was studied retrospectively in 21 patients who presented with a clinical suspicion of CFN entrapment. Patients ages ranged from 17 to 71 (mean 48.5). RESULTS: The lidocaine injection test (LIT) was positive in 19 patients, and of these, 17 underwent surgical decompression and subsequently experienced improved ability to dorsiflex their foot and reduced sensory abnormalities. CONCLUSION: The LIT is a simple, safe adjunctive test to help diagnose and also predict a successful outcome of surgical decompression of a CFN entrapment. The proposed mechanism of action of the LIT could lead to new, non-surgical treatments for CFN entrapment.

Outcome and Prognosis of Microsurgical Decompression in Idiopathic Severe Common Fibular Nerve Entrapment: Prospective Clinical Study.

OBJECTIVE: Compression of the common fibular nerve at the level of the fibular neck is considered to be the most frequent lower limb entrapment syndrome, which can be either idiopathic or secondary. Decompressive surgery is indicated only after failure of conservative treatment and/or severe neurologic deficit. The effectiveness of microsurgical decompression has been established only for secondary entrapment syndrome. The aim of this study is to assess the results of microsurgical decompression and establish the prognosis of idiopathic severe common fibular nerve entrapment. METHODS: Fifteen patients were included in this prospective clinical study and were followed at day 1 after surgery and later at 1, 6, and 12 months. More than half (64.3%) of patients had a total motor deficit (0/5). The median motor function preoperatively was 0/5. The average time of conservative treatment before surgery was 25.7 days (range 5-110 days). One patient refused surgical management. RESULTS: Thirteen out of 14 patients who underwent surgery showed significant motor function improvement. The median motor strength at 12 months was 4.5/5. Half of the patients regained normal motor function. The only patient who did not improve had the longest time to surgery interval (110 days). The patient who refused surgery showed no improvement (0/5 at 12 months). CONCLUSIONS: Microsurgical decompression should be considered early in the context of severe idiopathic common fibular nerve entrapment in order to get a favorable outcome.

Nerve Decompression and Restless Legs Syndrome: A Retrospective Analysis.

INTRODUCTION: Restless legs syndrome (RLS) is a prevalent sleep disorder affecting quality of life and is often comorbid with other neurological diseases, including peripheral neuropathy. The mechanisms related to RLS symptoms remain unclear, and treatment options are often aimed at symptom relief rather than etiology. RLS may present in distinct phenotypes often described as "primary" vs. "secondary" RLS. Secondary RLS is often associated with peripheral neuropathy. Nerve decompression surgery of the common and superficial fibular nerves is used to treat peripheral neuropathy. Anecdotally, surgeons sometimes report improved RLS symptoms following nerve decompression for peripheral neuropathy. The purpose of this retrospective analysis was to quantify the change in symptoms commonly associated with RLS using visual analog scales (VAS). METHODS: Forty-two patients completed VAS scales (0-10) for pain, burning, numbness, tingling, weakness, balance, tightness, aching, pulling, cramping, twitchy/jumpy, uneasy, creepy/crawly, and throbbing, both before and 15 weeks after surgical decompression. RESULTS: Subjects reported significant improvement among all VAS categories, except for "pulling" (P = 0.14). The change in VAS following surgery was negatively correlated with the pre-surgery VAS for both the summed VAS (r = -0.58, P < 0.001) and the individual VAS scores (all P < 0.01), such that patients who reported the worst symptoms before surgery exhibited relatively greater reductions in symptoms after surgery. CONCLUSION: This is the first study to suggest improvement in RLS symptoms following surgical decompression of the common and superficial fibular nerves. Further investigation is needed to quantify improvement using RLS-specific metrics and sleep quality assessments.

Electrophysiologic features of fibular neuropathy in childhood and adolescence.

INTRODUCTION: We studied patterns of nerve injury in pediatric common fibular (peroneal) neuropathy (CFN). METHODS: A retrospective analysis was performed on data from 53 children with CFN at a pediatric electromyography laboratory. RESULTS: Conduction block at the fibular head was present in 35% of patients. Deep fibular axonal loss was identified in 77%, while superficial fibular axonal loss was identified in 45%. The pathophysiology was predominantly axonal in 72%, mostly demyelinating in 6%, and mixed in 22%. Predominantly demyelinating lesions at the fibular head demonstrated sparing of the superficial fibular sensory nerve (P = 0.01, Fischer exact test). Predominantly axonal lesions had a moderate correlation between superficial and deep fibular axonal loss (Spearman r = 0.52; P = 0.0001). CONCLUSIONS: There is frequent axonal and fascicular injury in pediatric CFN, similar to adults. Deep and superficial fibular nerve involvements correlate in axonal lesions, whereas superficial fibular sensory fibers are often spared in demyelinating lesions. Muscle Nerve, 2016 Muscle Nerve 55: 693-697, 2017.

Common Fibular Nerve Compression: Anatomy, Symptoms, Clinical Evaluation, and Surgical Decompression.

This article thoroughly describes the clinical examination and treatment of common fibular (peroneal) nerve compression. Aspects discussed include the anatomy of the nerve, cause of entrapment, symptoms associated with impairment, and a surgical approach to decompress the entrapped nerve. The standard protocol for decompression as it would apply to the common fibular nerve tunnel is illustrated.

The sciatic nerve in human cadavers - high division or low formation?

Variations of the sciatic nerve have been extensively studied in the past including its relationship with the piriformis muscle and associated clinical conditions like piriformis syndrome and sciatica. In the present study we noticed some interesting variations of the sciatic nerve, which were slightly different from the cases described earlier. In the previous studies most of the authors described the higher division of sciatic nerve and none of them discussed its formation. In this study we tried to look its formation from the sacral plexus and its divisions in the thigh. We noticed that in one cadaver the two components of the sciatic nerve originated directly from the sacral plexus and coursed down without merging in the thigh. Should this be called a higher division or non formation of the sciatic nerve? On the other hand in two other cadavers, the two divisions after emerging separately from the sacral plexus, united in the gluteal region and in the thigh respectively. Should we call this as higher division or low formation of the sciatic nerve? In two other cadavers the sciatic nerve emerged from the greater sciatic foramen below the piriformis and divided in the gluteal region itself. Ideally this should be called as higher division of sciatic nerve.

The common fibular nerve (and its branches) in fetuses / El nervio fibular comun (y sus ramos) en fetos

The common fibular nerve (CFN), is a branch of the sciatic nerve (SN) that exits the popliteal fossa and is located at the tuberculum of the fibula. At the tuberculum of the fibula, the CFN bifurcates into deep (DFN) and superficial (SFN) fibular nerves. Forty fetuses were micro-dissected to (i) describe the course of the CFN in relation to the tuberculum and neck of the fibula in fetuses; (ii) describe the branches, distribution and relation of the DFN and SFN to muscles within the anterolateral compartment of the leg. The CFN, DFN and SFN were present in all specimens dissected; the CFN measured a mean length (mm) of 16.03 and 16.69 on the right and left sides respectively. Bifurcation of the CFN related to the tuberculum of fibula (right; left) - above 20/80 (25%); 14/80 (17.5%); below 6/80 (7.5%); 10/80 (12.5%) and at the tuberculum 54/80 (67.5%); 56/80 (70%). The DFN bifurcated into medial and lateral branches in 68/80 (85%) and 54/80 (67.5%) on the right and left sides, respectively. The SFN bifurcated into a medial branch in 78/80 (97.5%) and 76/80 (95%) on right and left sides, respectively and a lateral branch in 78/80 (97.5%) and 76/80 (95%) on right and left sides, respectively. The course and distribution of the CFN, DFN and SFN were consistent with the literature reviewed and descriptions found in standard anatomical textbooks. However, our findings show that the DFN has a variable number of branching patterns, which is unique to this fetal study and an intermediate branch of the SFN which was recorded in 3/80 cases.

El nervio fibular común (NFC), es un ramo del nervio isquiático (NI) que sale de la fosa poplítea y se ubica a nivel de la cabeza de la fíbula. A ese nivel, el NFC se bifurca en los nervios fibular profundo (NFP) y superficial (NFS). Cuarenta fetos fueron micro disecados para (i) describir el curso del NFC en relación con la cabeza y cuello de la fíbula en fetos; (ii) describir los ramos, distribución y relación del NFP y NFS con los músculos dentro del compartimento anterolateral de la pierna. El NFC, NFP y NFS estuvieron presentes en todos los especímenes disecados; el NFC presentó una longitud promedio de 16,03 y 16,69 (mm) en el lado derecho e izquierdo, respectivamente. La bifurcación del NFC se relacionó con la cabeza de la fíbula del lado derecho e izquierdo: por encima en 25% y 17,5%; por debajo 7,5% y 12,5 % y a nivel de la cabeza en 67,5 % y 70%. El NFP se bifurcó en ramos medial y lateral en un 85% en el lado derecho y 67,5% en el izquierdo. El NFS se bifurcó en una ramo medial en el 97,5% y 95% en los lados derecho e izquierdo, respectivamente, y un ramo lateral en el 97,5% y 95% del lados derecho e izquierdo, respectivamente. El curso y distribución del NFC, NFP y NFS coincidieron con la literatura revisada y textos de anatómia normal. Sin embargo, observamos que el NFP tiene un número variable de patrones de ramificación, único para este estudio fetal y un ramo intermedio del NFS que fue visto en 3/80 casos.

Influence of a fabella in the gastrocnemius muscle on the common fibular nerve in Japanese subjects.

The fabella is a sesamoid bone located in the proximal tendon of the gastrocnemius muscle. In rare cases, its presence may lead to a variety of clinical problems, including fabella syndrome and common fibular (CF) nerve palsy. The purpose of this study was to analyze the morphology of the fabella and CF nerve and discuss the influence of any existing fabellae on the size of the CF nerve. The morphology of the fabella and CF nerve in the popliteal region of the lateral head of the gastrocnemius muscle was investigated in 102 knees of 51 Japanese cadavers. The maximum circumference of the thigh, knee, and calf and the frequency, position, and size of the fabella were measured. In addition, the CF nerve width and thickness were measured proximal to the fabellar region and again as the CF nerve passed posterior, lateral, or medial to the region. A fabella was observed in 70 knees (68.6%). The CF nerve adjacent to the fabella was significantly wider and thinner than in the region proximal to the fabella (P < 0.001). In cases in which a bony fabella was present, there was a significant relationship between the thickness of the CF nerve and the circumference of the thigh and knee. The following factors were observed to contribute to the presence of a fabella causing alterations in the size of the CF nerve: a bony fabella, a CF nerve path posterior or lateral to the fabella, and subjects with a thin physique and bony fabella.

Anatomical study of motor branches from tibial nerve transfer to restore the deep fibular nerve / 中华显微外科杂志

Objective To explore the feasibility of tibial nerve motor branches transfer to the deep fibular nerve in an anatomical study.Methods Twenty-three sides lower limbs from 12 adult cadavers which preserved in Formalin were used for dissection of the tibial nerve and its all motor branches,and the proximal deep and superficial fibular nerve.Experimental measurement were performed for the parameters of each branch such as length,diameter,the location of original point relative to the level of the fibular head.The diameter of proximal part of the deep fibular nerve was measured simultaneously.Finally,the length from original point of each branch to the fibular neck was also measured during simulation of nerve transfer procedure.Results The average length of motor branches to the flexor digitorum longus muscle,to the flexor hallucis longus muscle and the superficial branches to the soleus muscle were (95.70 ± 13.40)mm,(96.90± 13.60)mm and (73.60 ± 12.00)mm respectively.Their average diameter were (0.63 ± 0.16)mm,(0.65 ±0.20)mm and ( 1.56 ± 0.26)mm respectively.The average diameter of proximal deep fibular nerve was (2.54± 0.26)mm.Based on length,branches to the flexor digitorum longus muscle and flexor hallucis longus muscle were adequate for direct nerve transfer to the deep fibular nerve in all specimens without interpositional grafr.And in 22 specimens (95.7 percent),the superficial branches to the soleus muscle were long enough to directly transfer.Other branches of the tibial nerve were not adequate for direct nerve transfer Conclusion This study confirmed the anatomical feasibility of using motor branches from tibial nerve for direct transfer to restore the deep fibular nerve.The superficial branches to soleus muscle were the best donor nerve if considering the branches,length,diameter and the difficulty of surgical procedures.

Morfometría de los nervios isquiático, tibial y fibular común en el hombre / Morphometry of the sciatic, tibial and common fibular nerves in man

El nervio isquiático, el más extenso del cuerpo humano, emerge de la pelvis por el foramen isquiático mayor, dividiéndose proximal a la articulación de la rodilla en los nervios tibial y fibular común. Con frecuencia, estos nervios son afectados por accidentes, por tanto, la microcirugía reparadora requiere de detallada información anatómica para efectuar con éxito sus procedimientos. El nervio isquiático puede ser lesionado por heridas penetrantes, en las luxaciones posteriores de la articulación coxal y por inyecciones intramusculares mal aplicadas en la región glútea, siendo rara la lesión del nervio tibial por estar situado profundamente protegido. En cambio, la lesión del nervio fibular común, es frecuente debido a su posición superficial, quedando muy expuesto cuando abandona la fosa poplítea y rodea el cuello de la fíbula. Realizamos el estudio debido a la escasa información morfométrica y estereológica de estos nervios. Se disecaron en 5 cadáveres de individuos adultos, de sexo masculino los nervios isquiático, tibial y fibular común. Se obtuvieron secciones transversales de cada uno de los nervios a nivel de la división del nervio isquiático y del origen de los nervios tibial y fibular común. Realizamos cortes de 5 µm de grosor, los que fueron teñidos con H.E. Obtuvimos información cuantitativa sobre medidas morfométricas, determinamos el número de fibras nerviosas de cada fascículo así como el número de fascículos existente en cada nervio. Además, determinamos, por planimetría a través del conteo de puntos, el área de los fascículos que constituían cada nervio. El número de fascículos en el nervio isquiático varió de 63 a 70, con un promedio de 66,8 (D. E. 2,59). En el nervio tibial, el número de fascículos varió de 35 a 43, con un promedio de 30 (D. E. 3,00) y en el nervio fibular común el número de fascículos varió de 17 a 25, con un promedio de 21 (D. E. 2,92). El número promedio de fibras en el nervio ciático fue de 64.535 (D. E. 3.193). En los ...

The sciatic nerve, the longest of the human body, emerging from the pelvis through the greater sciatic foramen, dividing proximal to the knee joint in the tibial and common fibular nerves. Frequently these nerves are affected by accidents, therefore, the repairing microsurgery requires detailed anatomical information in order to successfully complete these procedures. The sciatic nerve can be damaged by penetrating injuries in the posterior luxations of the hip joint, and by intramuscular injections, given incorrectly the gluteal region. Injury to the tibial nerve is rare as it is deeply located and protected. On the other hand, injury to the common fibular nerve is frequent due to its superficial position, leaving it exposed when it leaves the popliteal fossa and surrounds the fibular neck. The study was conducted due to scarce morphometric and stereologic information on these nerves. The sciatic tibial and common fibular nerves in five cadavers of individual male adults were dissected. Transverse section of each of the nerves were obtained at the level of the division of the sciatic nerve and of the origin of the tibial and common fibular nerves. Sections of 5 µm were cut which were stained with H.E. We obtained quantitative information regarding morphomtric measurements, determined the number of nerve fibres of each fascicle, as well as the number of existing fascicles in each nerve. We also determined by planimetry, through counting of points, the area of the fascicles that constituted each nerve. The number of fascicles in the sciatic nerve varied from 63 to 70 with an average of 66.8 (S.D. 2.59). In the tibial nerve the number of fascicles varied from 17 to 25 with an average of 21 (S.D. 2.92). The mean number of fibres in the sciatic nerve as of 64,535 (S.D. 3,193). In the tibial nerve it was 40,317 (S.D. 4,067) and in the common fibular nerve it was: 22,191 (S.D. 1,038). The median area of the sciatic, tibial and common fibular nerves was: 11,42 mm².