Deep Peroneal Research Articles

An anatomical study and clinical value of the innervation of hallucis longus muscle

Objective To study the anatomy of the innervation of hallucis longus muscle,and discuss the clinical value of the innervation.Methods Nineteen limbs of 10 cadavers were studied.There were 4 female cadavers and 6 male cadavers.Nine were left legs and 10 were right legs.The specimens were anatomied to confirm the tibialis anterior,extensor digitorum longus and hallucis longus muscle.The innervation of hallucis longus muscle was been observed along the deep peroneal nerve.Measuring the muscular branches length (nerve length,NL),the distance from the tip of the fibular head to the muscular brance (nerve-fibula head length,NFL),and fibular length (fibula length,FL).The hematoxylin and eosin stain was used to observe the numbers of nerve fascicle for each branch of EHL.Results Twenty-three muscle branches of hallucis longus muscle were found in 19 limbs,15 limbs had a single branch,4 limbs had the double branches.All branches were originated in the deep peroneal nerve.Fourteen branches were into hallucis longus muscle from the fibular side,3 from anterior side,6 from the tibial side.The fibula length was 37.0±1.9 cm (range,34.5-40.6 cm); the nerve-fibula head length was 89.0±5.2 mm (range,75.4-97.2 mm);nerve length was 48.5±5.0 mm (range,33.6-57.4 mm); the nerve-fibula head length/fibula length was 0.245±0.020 (range,0.211-0.280).Among 15 specimens with single branch,3 branches had a unique nerve fascicle and 12 had two fascicles.Among 4 specimens with doulbe branches,only 1 branch had two fascicles,7 branches had a unique fascicle.Conclusion Special anatomical features of muscular branches might be the reason of isolated extensor hallucis longus dysfunction. Key words: Neuroanatomy; Peroneal nerve; Trauma, nervous system

Deep peroneal nerve palsy during growth spurt: a case report

Peripheral nerve injuries may have a number of causes, most commonly mechanical. We describe a case of a deep peroneal nerve palsy in an adolescent boy which coincided with a large growth spurt. Spontaneous recovery of full function was seen without intervention. In the absence of any other causative factors, we believe that this growth spurt resulted in temporary compression of the deep peroneal nerve at the level of the knee producing transient neurapraxia.

Neuromusculotendinous Transfer

An original surgical technique for the correction of drop foot is demonstrated. Eighteen patients with drop foot underwent transfer of the lateral, medial, or both heads of the gastrocnemius muscle to the tendons of the anterior and/or lateral muscle group of the lower leg. The transferred muscle was reinnervated by nerve coaptation between the undamaged proximal part of the deep peroneal nerve and the motor branch of the tibial nerve supplying the gastrocnemius muscle. In all patients, the transferred gastrocnemius muscle showed signs of reinnervation within an average of 6 months after operation. Ten patients achieved excellent results, having regained stable, fully automatic walking without foot inversion/eversion and active range of foot movement of at least 40 degrees. Four patients achieved good results with active range of movement of less than 40 degrees but very stable functional gait. Satisfactory results were presented in three cases with stable ankle motion. Two of three cases had dual transfer of the gastrocnemius muscle and had a very stable ankle joint. In one fair case, the treatment improved stability and the patient was able to walk. To compensate for the loss of function of the anterior muscle compartment, neuromusculotendinous transfer of the gastrocnemius muscle has proved to be highly successful. Voluntary movement of the transferred muscle and fully automatic walking was achieved in the majority of patients treated. In contrast to the commonly used treatment of tibialis posterior muscle transfer, no reeducation of the transferred muscle was needed.

F-Wave Abnormalities in a Patient with Possible Chronic Exertional Compartment Syndrome

The F-waves demonstrated here were obtained from a 20-yr-old woman referred for several months of bilateral exertional calf pain (Fig. 1). In addition, she reported that 5 days before testing, she developed severe bilateral calf pain after walking 1 mile, and by the next day, she had developed left lateral foot numbness and weakness at the left ankle. On physical examination, sensation was impaired to light touch and pinprick over the left lateral malleolus and the lateral aspect of the foot. Reflexes were intact and symmetric at the bilateral patella and achilles. Strength was impaired with all movements of her left ankle and toes only.FIGURE 1: F-wave responses in the left lower limb. Runs 1 and 2 were measured at the extensor digitorum brevis, run 3 was measured at the tibialis anterior, and the final run was measured at the abductor hallucis.Sural sensory, fibular motor, and tibial motor nerve conduction studies were unremarkable. Interestingly, no F-waves could be obtained when measured from the fibular nerve at the extensor digitorum brevis bilaterally. However, when measured from the fibular nerve at the tibialis anterior and the tibial nerve at abductor hallucis, F-wave responses were obtained with normal latency and penetrance. Needle examination was not performed because weakness had been present only for several days. Chronic exertional compartment syndromes (CECSs) can affect any lower limb compartment, and it seems to affect the lower leg anterior compartment most frequently.1 Although early research on acute compartment syndromes documented resultant neuropathy,2,3 electrodiagnostic findings in CECS have not been definitively characterized, and previous studies of electrodiagnostic evaluations in patients with a presumptive diagnosis of CECS have been unremarkable.4 Therefore, it is likely that elevated compartment pressures may cause neuropathy if pressures of sufficient severity and duration are produced, although this threshold remains uncertain. In our patient, we observed the absence of F-wave responses from the bilateral extensor digitorum brevis only. These findings are suggestive of a subtle neuropathy of the deep fibular nerve in a clinical scenario strongly suggestive of CECS of the anterior compartment of the lower leg, and we propose that these findings may represent the mildest findings of CECS that may be appreciated on electrodiagnostic studies. To summarize, CECS of the lower leg is a well-recognized diagnosis, and although not the diagnostic test of choice for this diagnosis, these patients are referred not infrequently for electrodiagnostic testing, as symptoms may include pain, weakness, and numbness. As such, the electromyographer should be aware of this entity and potential electrodiagnostic abnormalities.

Clinical Results of Transferring a Motor Branch of the Tibial Nerve to the Deep Peroneal Nerve for Treatment of Foot Drop

Foot drop is a very debilitating condition affecting patients' daily activities, and its treatment has been a challenge for neurosurgeons. Grafting the peroneal or sciatic nerve usually results in poor outcomes. Our previous anatomic study demonstrated the feasibility of transferring a motor branch of the tibial nerve to the deep peroneal nerve at the level of the popliteal fossa. To demonstrate the outcomes obtained after the transfer of a branch of the tibial nerve to the peroneal nerve for recovery of foot drop. A retrospective review of 13 patients with foot drop caused by injuries to a lumbar root or the sciatic or peroneal nerve, who underwent a transfer of the nerve of the soleus muscle to the deep peroneal nerve. The results were evaluated using the British Medical Research Council grading system. Three patients were lost to follow-up. Of the remaining 10 patients, the outcomes were considered good (Medical Research Council grade M3 or M4) in 2 patients (20%) concerning ankle dorsiflexion and in 2 patients concerning toe extension (20%). One patient reported a reduced calf circumference. The transfer of the nerve of the soleus muscle to the deep peroneal nerve demonstrated poor results in most of the patients, although favorable outcomes were observed in a few subjects. Due to the inconsistency of the results, we do not favor the routine use of this technique for the treatment of foot drop.

The Positive Effect of Neurolysis on Diabetic Patients with Compressed Nerves of the Lower Extremities: A Systematic Review and Meta-analysis.

Background:Despite proven benefits of upper extremity nerve decompression in diabetics, neurolysis for diabetic patients with lower extremity (LE) nerve compression remains controversial.Methods:A search of ClinicalTrials.gov and Cochrane clinical trials registries, CENTRAL (The Cochrane Library), MEDLINE, EMBASE, LILACS, CINAHL, SCOPUS, and Google Scholar from 1962 to 2012, yielded 1956 citations. Any potential randomized or quasi-randomized controlled trials and observational cohort studies of diabetics with neurolysis of the common peroneal nerve, deep peroneal nerve, or tibial nerve were assessed. We included articles in any language that 1) provided information about diabetic patients who had neurolysis for symptomatic nerve compression diagnosed by (+) Tinel sign or electrodiagnostic study, and 2) quantified outcomes for pain, sensibility, or ulcerations/amputations. Case reports, review articles, animal or cadaver studies, and studies with <10 patients were excluded. We assessed pain relief, recovery of sensibility, and postoperative incidence of ulcerations/amputations at follow-up >3 months. A meta-analysis of descriptive statistics was performed.Results:Ten clinical series with a mean clinical relevance score of 70% and a mean methodologic quality score of 50% met inclusion criteria. We included 875 diabetic patients and 1053 LEs. Pain relief >3 points on visual analog scale occurred in 91% of patients; sensibility improved in 69%. Postoperative ulceration/amputation incidence was significantly reduced compared to preoperative incidence (odds ratio = 0.066, 95% confidence interval = 0.026–0.164, P < 0.0001).Conclusions:Observational data suggest that neurolysis significantly improves outcomes for diabetic patients with compressed nerves of the LE. No randomized controlled trials have been published.

Teaching Video Neuro Images : A teenager with a rare movement disorder

A 17-year-old patient with no medical or psychiatric illness presented with a 4-year history of painless twitching of the toes of his right foot (video on the Neurology ® Web site at [www.neurology.org][1]). The movements subsided in deep sleep. Neurologic examination, EEG, and MRI brain/lumbosacral spine were normal. Electrophysiology showed axonal neuropathy of the right deep peroneal nerve. [1]: http://www.neurology.org/

Transferring motor branches from proximal tibial nerve for treatment of high fibular nerve injuries: an anatomical study

Objective To observe the anatomy of proximal tibial nerve,so as to assess the feasibility of transferring motor branches from proximal tibial nerve for treatment of the high fibular nerve or long-segment injuries.Methods Totally 23 sides of lower limbs from 12 adult cadavers were included in the present study.The branching pattern,length,diameter of motor branches of the tibial nerve in the proximal leg,location of original point relative to fibular head level and the distance from original point to the fibular neck were examined.Intraneural dissection from the bifurcation of the common fibular nerve to the proximal(deep fibular nerve and superficial fibular nerve) was performed,and then the maximum dissected length and the diameter of deep fibular nerves were observed.The deep fibular nerve was severed at the top site and simulating transfer was performed;the feasibility of suturing the motor branches from proximal tibial nerve and the deep fibular nerve was assessed.Results There were three main motor branches at the proximal leg,including the branches to the lateral and medial head of the gastrocnemius and to the soleus muscle,with the length being(36.3±9.6) mm,(44.7±8.6) mm and(53.2±9.9) mm,respectively.The maximum length of intraneural dissection of the common fibular nerve was(59.3±7.2) mm.After dissection,the branches to the soleus muscle and the lateral head of the gastrocnemius were long enough for direct nerve suture with the deep fibular division in all cadavers without tension.The branches to the medial head of the gastrocnemius were long enough for nerve suture in 21 sides(91.3%).Conclusion After intraneural dissection of the common fibular nerve,the motor branches from proximal tibial nerve can be transferred to restore the deep fibular nerve for treating high fibular nerve injuries.The branch to the soleus muscle is the best choice considering its length and diameter.

Hindfoot Arthroscopy: A Systematic Surgical Approach for Identifying Anatomy and Hindfoot Pathology (SS-47)

Hindfoot arthroscopy has been recognized as a safe and valid technique for treating hindfoot pathology, while also facilitating an earlier return to sporting activities when compared to the traditional open approach. Standardized examinations for anterior ankle arthroscopy, such as Ferkel’s 21 point evaluation, have been described in the literature, however a systematic surgical approach for performing hindfoot arthroscopy has not yet been described. The objective of this study is to present a structured systematic surgical approach for identifying relevant anatomical structures and pathology during hindfoot arthroscopy. In addition, we report the clinical results of a case series of 22 patients whom had hindfoot arthroscopy performed for posterior ankle impingment. The systematic surgical approach divides the extra-articular structures of the hindfoot into quadrants as defined by the intermalleolar ligament. Twenty-two patients underwent hindfoot arthroscopy for the treatment of posterior ankle impingement syndrome. The mean follow-up time was 20 months (range, 7 – 35 months). Standard patient reported outcome questionnaires in the Foot and Ankle Outcome Score (FAOS) and Short Form-12 (SF-12) general health survey were administered at standard time points after surgery. Return to sporting activities was also calculated as the time period from the date of surgery until the patient was able to participate at their previous level of activity. The mean FAOS score improved from 58.17 points (range 22.22 – 94.45) preoperatively to 86.06 points (range 47.22 – 100) postoperatively (p < 0.0001). The mean SF-12 scores showed similar improvement with a mean of 65.62 points (range 41.88 – 95.30) preoperatively to 86.88 points (range 55.94 – 95.55) postoperatively (p < 0.0001). 19 patients reported competing at some level of athletic sport prior to surgery. All patients returned to their previous level of competition after surgery. The mean time to return to sporting activities was 12 weeks (range 6 – 16 months). Two complications were reported post-operatively; one wound infection and one case of dysthesia of the deep peroneal nerve. Hindfoot arthroscopy is a safe and effective treatment strategy for posterior ankle impingement syndrome. In addition, it allows the patients a rapid return to sporting activities.

Hindfoot Arthroscopic Surgery for Posterior Ankle Impingement

Background: Hindfoot arthroscopic surgery has been described as a minimally invasive surgical treatment for posterior ankle impingement syndrome. The current article describes a systematic approach for identifying relevant hindfoot structures as well as the clinical results of a case series. Purpose: To present a structured systematic surgical approach for identifying relevant anatomic structures and abnormalities during hindfoot arthroscopic surgery. In addition, we report the clinical results of a case series. Study Design: Case series; Level of evidence, 4. Methods: The systematic surgical approach divides the extra-articular structures of the hindfoot into quadrants as defined by the intermalleolar ligament. Twenty-two patients underwent hindfoot arthroscopic surgery for the treatment of posterior ankle impingement syndrome. The mean follow-up time was 25 months (range, 14-35 months). Standard patient-reported outcome questionnaires of the Foot and Ankle Outcome Score (FAOS) and Short Form–12 (SF-12) general health survey were administered at standard time points after surgery. Return to sporting activities was also calculated as the time period from the date of surgery until the patient was able to participate at their previous level of activity. Results: The mean FAOS score improved from 59 (range, 22-94) preoperatively to 86 (range, 47-100) postoperatively (P < .01). The mean SF-12 score showed similar improvement with a mean of 66 (range, 42-96) preoperatively to 86 (range, 56-98) postoperatively (P < .01). Nineteen patients reported competing at some level of athletic sport before surgery. All patients returned to their previous level of competition after surgery. The mean time to return to sporting activities was 12 weeks (range, 6-16 weeks). Two complications were reported postoperatively: 1 wound infection and 1 case of dysesthesia of the deep peroneal nerve. Conclusion: Hindfoot arthroscopic surgery is a safe and effective treatment strategy for posterior ankle impingement syndrome. In addition, it allows the patients a rapid return to sporting activities.

Unusual peroneal nerve palsy caused by intraneural ganglion cyst: pathological mechanism and appropriate treatment

The origin of the peroneal intraneural ganglion and the outcome of treatment are still controversial. We report here three cases with peroneal intraneural ganglion and discuss the appropriate treatment. In our cases, 58-, 62-, and 65-year-old patients were operated on with extraneural decompression and epineurotomy within 4 months after onset of drop foot. Two cases demonstrated intraneural ganglion connecting to the articular branch and traversing to the deep and common peroneal nerve. At the 1-year follow-up, paralyzed peroneal nerve could be recovered in all patients even with residual ganglion. We propose correct early diagnosis, simple exoneural dissection, and atraumatic epineurotomy for the successful treatment of peroneal intraneural ganglion. Disruption of the stalk in the articular branch is a key point to prevent recurrence. For early diagnosis, clinicians should be aware of the existence of this rare lesion.

Low‐frequency electrical stimulation prevents muscle loss in mice with chronic kidney disease (CKD) by decreasing atrogin1 and MurF‐1 expression

HypothesisLow‐frequency electrical stimulation (LFES) in muscle attenuates muscle atrophy induced by CKD.MethodCKD was induced in 20g mice by 5/6th nephrectomy. Electrode insertion points were selected using acupunture therapy guidelines. The positive needle was inserted under the fibula head near the superficial and deep fibular nerves (site name: Yang ling qian). The negative needle was inserted lateral to the knee joint under the fibula head near the fibular nerve (site name: Ho san li). The needles were connected to an SDZ‐蕅 electronic acupuncture device delivering a constant electical pulse (20Hz, 1mA) daily for 15 minutes over 4 weeks.ResultsSoleus and EDL muscle weights from uremic mice were significantly increased by LFES (P&lt;0.05). LFES blunted the increase in CKD‐induced muscle proteolysis and improved phosphorylation of Akt (2.3‐fold, P&lt;0.001) and FoxO3a (2.1‐fold, P&lt;0.01). mRNAs of proteolytic atrogin‐1 and MuRF‐1 E3 ubiquitin ligases were attenuated by LFES. LFES concomitantly improved protein synthesis (increased phosphorylation of mTOR and p70S6K) and myogenesis (increased levels of MyoD, myogenin, and eMyHC) in muscles of CKD mice.ConclusionsLEFS can prevent CKD‐induced muscle loss by a multi‐faceted mechanism affecting myogenesis, protein degradation and synthesis.Support: NIH AR060268, and the NSF of China (30971471)

Repetitive Electroacupuncture Attenuates Cold‐Induced Hypertension and Simultaneously Enhances rVLM Preproenkephalin mRNA Expression

Acupuncture lowers elevated blood pressure in clinical and experimental hypertension, likely through an opioid mechanism. To mimic human studies, we performed repeated electroacupuncture (EA) on unanesthetized male SD rats (150g) exposed to cold (5¡ãC) for 11 weeks. Systolic tail cuff blood pressures (SBP) were measured weekly. Rats were randomly divided into EA‐hypertension (n=9), sham (n=6) and untreated hypertension groups (n=6) after 6 weeks of cold exposure. Blood pressures measured outside the cold room (25¡ãC) stabilized at an elevated level in the three groups. EA and sham groups received either repetitive EA (1–4 mA, 2 Hz, 0.5 ms) at ST36–37 acupoints (overlying deep peroneal nerve) or sham (needle placement without electrical stimulation) for 30 min twice weekly for 5 weeks. The elevated SBP in the EA group was reduced after 5 sessions and remained low throughout EA treatment (155 ¡À 4 vs. 187 ¡À 3 mmHg EA vs. sham). The relative ratio of preproenkephalin mRNA (normalized to 18s) in rVLM 72 hr after the terminal EA treatment was increased in the EA (14.3¡À1) compared to the sham group (4.3¡À0.5), which was similar to values in the untreated hypertensive rats (4.3¡À0.6). These data suggest that the prolonged inhibitory effect of EA is related to prolonged increases of opioid mRNA expression in the rVLM

Proximal Tibial Osteotomy and Taylor Spatial Frame Application for Correction of Tibia Vara in Morbidly Obese Adolescents

Four percent of children and adolescents in the United States are morbidly obese. Treatment for tibia vara includes proximal tibial osteotomy and correction with a Taylor Spatial Frame (TSF). There are no reports that specifically examine the success of this technique in morbidly obese adolescents. A retrospective review was conducted of patients between 12 and 18 years of age with a body mass index for age at or above the 99th percentile who had undergone gradual correction of tibia vara with proximal tibial osteotomy and application of a TSF at our institution between 2005 and 2009. Deformity analysis was performed on full-length standing anteroposterior radiographs of both lower extremities and lateral radiographs of the involved tibia obtained preoperatively and at latest follow-up. All complications were recorded. Fourteen patients met the inclusion criteria. The mean age was 13 years. The average body mass index was 45 kg/m. Preoperative deformity analysis demonstrated a mean mechanical axis deviation of 90 mm, mean mechanical medial proximal tibial angle of 66 degrees, and mean posterior proximal tibial angle of 80 degrees. Analysis at an average follow-up of 14 months demonstrated a mean mechanical axis deviation of 10 mm, mean mechanical medial proximal tibial angle of 88 degrees, and mean posterior proximal tibial angle of 81 degrees. Complications specifically related to the TSF occurred in 2 patients. Both experienced strut disengagement and loss of osteotomy position. This was treated with refastening of the strut and a new program of deformity correction. Complications related to the deformity correction occurred in 3 patients. One had premature fibular consolidation requiring repeat osteotomy, 1 developed a transient partial deep peroneal nerve palsy, and 1 experienced thigh soft tissue irritation from the proximal ring necessitating early TSF removal. One patient had a residual leg-length discrepancy that required tibial lengthening. Correction of tibia vara with proximal tibial osteotomy and application of a TSF is an effective treatment option in morbidly obese adolescents. Associated complications are minimal. Level IV-therapeutic study.

Electrodiagnostically Confirmed Posttraumatic Neuropathy and Associated Clinical Exam Findings With Lisfranc Injury

Patients with a Lisfranc injury often complain of persistent pain radiating from the Lisfranc joint up or down the first dorsal web space, accompanied by decreased sensation. We hypothesized that these symptoms were related to a posttraumatic neuropathy of the terminal medial branch of deep fibular (peroneal) nerve (MBDFN) and that by recognizing this symptom an earlier diagnosis of Lisfranc injury may be possible. Twelve patients with diagnosis of subtle unilateral Lisfranc injury, confirmed by standing X-ray, CT, or bone scan, were enrolled. Standardized antidromic sensory nerve conduction studies of MBDFN were performed bilaterally within 2 months postinjury and prior to surgical intervention. The contralateral, normal side was used as a control. All patients were tested for decreased 2-point discrimination in the first dorsal web space on both lower extremities. Sensory nerve action potential of the MBDFN was absent, with decreased 2-point discrimination on the injured side in all patients. Lisfranc injuries were associated with a posttraumatic neuropathy of the MBDFN and decreased 2-point discrimination in the first dorsal web space. The finding of altered sensation in the first dorsal web space may help the practitioner to earlier diagnosis of a Lisfranc injury. Level III, case control study.

Is there an anatomical marker for the deep peroneal nerve in midfoot surgical approaches?

The deep peroneal nerve (DPN) passes over the dorsum of the foot and is susceptible to injury during surgical approaches. The purpose of this anatomical study is to examine the relationship of the extensor hallucis brevis (EHB) as it passes over the DPN. Ten cadaver feet specimens were dissected and the anatomical structures surrounding the neurovascular bundle containing the DPN were examined. In nine out of the ten specimens the DPN was under the EHB musculotendinous junction. In one case it passed through the musculotendinous junction. This cadaver study has found a consistent easily identifiable landmark for protecting the neurovascular bundle containing the DPN during dorsal midfoot surgery.

BLOQUEIOS DOS NERVOS PERIFÉRICOS DO PÉ – UTILIDADE EM CIRURGIA DERMATOLÓGICA

Introdução: As lesões acrais de carácter neoplásico tornam imperativo programar a intervenção cirúrgica atempadamente, e, se possível, minimizando o impacto orgânico em doentes habitualmente idosos, com múltiplas comorbilidades. O bloqueio loco-regional dos nervos periféricos engloba técnicas relativamente fáceis de executar e seguras, quando cumpridas rigorosamente. Discussão: A inervação do pé, ao nível do tornozelo, é relativamente superficial e consiste em 5 ramos nervosos: (1) nervo tibial posterior; (2) nervo peroneal profundo; (3) nervo peroneal superficial; (4) nervo sural e (5) nervo safeno. Os autores analisam as técnicas anestésicas dos nervos periféricos do pé, revendo os procedimentos, as indicações e possíveis complicações. Conclusão: Podendo atingir taxas de sucesso de 95%, as técnicas de bloqueio anestésico dos nervos periféricos do pé permitem optimizar de forma segura os re- cursos disponíveis em cirurgia dermatológica.PALAVRAS-CHAVE – Bloqueio loco-regional; Nervos Periféricos; Pé; Doenças da Pele.

Hereditary Neuropathy with Liability to Pressure Palsy: A Recurrent and Bilateral Foot Drop Case Report

Hereditary neuropathy with liability to pressure palsy is characterized by acute, painless, recurrent mononeuropathies secondary to minor trauma or compression. A 16-year-old boy had the first episode of right foot drop after minor motorcycle accident. Electromyography revealed conduction block and slowing velocity conduction of the right deep peroneal nerve at the fibular head. After motor rehabilitation, he fully recovered. Six months later he had the second episode of foot drop in the opposite site after prolonged squatting position. Electromyography revealed sensorimotor polyneuropathy of left peroneal, sural, posterior tibial, and deep peroneal nerves and also of ulnar, radial, and median nerves of both upper limbs. Histological examination revealed sensory nerve demyelination and focal thickenings of myelin fibers. The diagnosis of hereditary neuropathy with liability to pressure palsy was confirmed by PMP22 deletion of chromosome 17p11.2. He started motor rehabilitation and avoidance of stressing factors with progressive recovery. After one-year followup, he was completely asymptomatic. Recurrent bilateral foot drop history, “sausage-like” swellings of myelin in histological examination, and the results of electromyography led the authors to consider the diagnosis despite negative family history. The authors highlight this rare disease in pediatric population and the importance of high index of clinical suspicion for its diagnosis.

Prevalence of Upper and Lower Extremity Tinel Signs in Diabetics: Crosssectional Study from a United States, Urban Hospital-based Population

Objective: To evaluate the prevalence of the Tinel Sign in the upper and lower extremities of patients with diabetes in an urban community. Methods: An IRB-approved, prospective, cross-sectional, descriptive study was performed on patients with diabetes during their visit to the endocrinologist. Eighty-one consecutive patients (162 sides) were examined by a fellowship-trained Hand Surgeon, experienced in performing the “Tinel Sign”. Mean duration of diabetes was 18.5 years. In the upper extremity known sites of anatomic entrapment were percussed; median nerve at the wrist (carpal tunnel), ulnar nerve at the elbow (cubital tunnel), radial sensory nerve in the forearm, and a negative control site. In the lower extremity, sites were tibial nerve at ankle (tarsal tunnel), proximal tibial nerve (soleal sling), common peroneal nerve at fibular neck (fibular tunnel), superficial peroneal nerve, deep peroneal nerve over dorsum of the foot, and a negative control site. Neuropathy was defined as a score greater than 4 on the Michigan Neuropathy Screening Instrument (MNSI). Statistical evaluation included linear regression, analysis of variance, and Tukey’s post hoc test. Results: 100% of the control sites had absent Tinel Sign. MNSI score and number of positive Tinel Signs were highly correlated ( r=0.94, p=0.001). Upper extremity, prevalence of Tinel Sign in patients with neuropathy (i.e. MNSI >4) ranged from 46.2% to 65% compared to 2.4% to 19.5% without neuropathy (MNSI < 4). Lower extremity prevalence ranges were 23% to 59% with neuropathy and 0% to 17.1% without neuropathy. The chances of having a positive Tinel Sign in the contralateral limb were 38.2%, 42.2%, 44.7% and 48.4% for carpal tunnel, cubital tunnel, fibular tunnel and tarsal tunnel, respectively. Conclusion: Presence of a Tinel sign was highly correlated with presence of neuropathy in diabetics.

Clinical Characteristics of Peroneal Nerve Palsy by Posture

ObjectivePosture induced common peroneal nerve (CPN) palsy is usually produced during the prolonged squatting or habitual leg crossing while seated, especially in Asian culture and is manifested by the onset of foot drop. Because of its similarity to discogenic foot drop, patients may be diagnosed with a lumbar disc disorder, and in some patients, surgeons may perform unnecessary examinations and even spine surgery. The purpose of our study is to establish the clinical characteristics and diagnostic assessment of posture induced CPN palsy.MethodsFrom June 2008 to June 2012, a retrospective study was performed on 26 patients diagnosed with peroneal nerve palsy in neurophysiologic study among patients experiencing foot drop after maintaining a certain posture for a long time.ResultsThe inducing postures were squatting (14 patients), sitting cross-legged (6 patients), lying down (4 patients), walking and driving. The mean prolonged neural injury time was 124.2 minutes. The most common clinical presentation was foot drop and the most affected sensory area was dorsum of the foot with tingling sensation (14 patients), numbness (8 patients), and burning sensation (4 patients). The clinical improvement began after a mean 6 weeks, which is not related to neural injury times. Electrophysiology evaluation was performed after 2 weeks later and showed delayed CPN nerve conduction study (NCS) in 24 patients and deep peroneal nerve in 2 patients.ConclusionWe suggest that an awareness of these clinical characteristics and diagnostic assessment methods may help clinicians make a diagnosis of posture induced CPN palsy and preclude unnecessary studies or inappropriate treatment in foot drop patients.