Tibial Compound Muscle Action Potential Research Articles

Polydeoxyribonucleotide and Shock Wave Therapy Sequence Efficacy in Regenerating Immobilized Rabbit Calf Muscles.

This study primarily aimed to investigate the combined effects of polydeoxyribonucleotide (PDRN) and extracorporeal shock wave therapy (ESWT) sequences on the regenerative processes in atrophied animal muscles. Thirty male New Zealand rabbits, aged 12 weeks, were divided into five groups: normal saline (Group 1), PDRN (Group 2), ESWT (Group 3), PDRN injection before ESWT (Group 4), and PDRN injection after ESWT (Group 5). After 2 weeks of cast immobilization, the respective treatments were administered to the atrophied calf muscles. Radial ESWT was performed twice weekly. Calf circumference, tibial nerve compound muscle action potential (CMAP), and gastrocnemius (GCM) muscle thickness after 2 weeks of treatment were evaluated. Histological and immunohistochemical staining, as well as Western blot analysis, were conducted 2 weeks post-treatment. Staining intensity and extent were assessed using semi-quantitative scores. Groups 4 and 5 demonstrated significantly greater calf muscle circumference, GCM muscle thickness, tibial nerve CMAP, and GCM muscle fiber cross-sectional area (type I, type II, and total) than the remaining three groups (p < 0.05), while they did not differ significantly in these parameters. Groups 2 and 3 showed higher values for all the mentioned parameters than Group 1 (p < 0.05). Group 4 had the greatest ratio of vascular endothelial growth factor (VEGF) to platelet endothelial cell adhesion molecule-1 (PECAM-1) in the GCM muscle fibers compared to the other four groups (p < 0.05). Western blot analysis revealed significantly higher expression of angiogenesis cytokines in Groups 4 and 5 than in the other groups (p < 0.05). The combination of ESWT and PDRN injection demonstrated superior regenerative efficacy for atrophied calf muscle tissue in rabbit models compared to these techniques alone or saline. In particular, administering ESWT after PDRN injection yielded the most favorable outcomes in specific parameters.

The relationship between nerve conduction studies and neuropathic pain in sciatic nerve injury due to intramuscular injection.

BackgroundSciatic nerve injury due to intramuscular injection (SNIII) is still a health problem. This study aimed to determine whether there is a correlation between neuropathic pain and electrodiagnostic findings in SNIII.MethodsPatients whose clinical and electrodiagnostic findings were compatible with SNIII participated in this retrospective cohort study. Compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes of the sural, superficial peroneal, peroneal, and tibial nerves were graded from 1 to 4. Leeds assessment of neuropathic symptoms and signs scale (LANSS) was applied to all patients.ResultsForty-eight patients were included in the study, 67% of whom had a LANSS score ≥ 12. Sural SNAP amplitude abnormalities were present in 8 (50%) out of 16 patients with a LANSS score < 12, and 28 (87.5%) out of 32 patients with a LANSS score ≥ 12, with significant differences between the groups (P = 0.011). There was a positive correlation between the LANSS score and the sural SNAP amplitude grading (P = 0.001, r = 0.476). A similar positive correlation was also found in the LANSS score and the tibial nerve CMAP amplitude grading (P = 0.004, r = 0.410).ConclusionsThis study showed a positive correlation between the severity of tibial nerve CMAP/sural SNAP amplitude abnormality and LANSS score in SNIII. Neuropathic pain may be more common in SNIII patients with sural nerve SNAP amplitude abnormality.

Bilateral Nerve Conduction Studies Must Be Considered in the Diagnosis of Sciatic Nerve Injury Due to Intramuscular Injection

Objectives: Although compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes of the nerves are reduced in sciatic nerve injury due to intramuscular injection (SNIII), they may still be higher than the reference values if there is a mild axonal degeneration. In this case, comparing the outcomes of nerve conduction studies of intact and affected lower extremities becomes important. We aimed to determine the role of this comparison in the diagnosis of SNIII. Methods: Patients with SNIII were included. Reference values for lower extremity nerve conduction studies were obtained from healthy participants. Peroneal, posterior tibial, superficial peroneal, and sural nerve conduction studies were performed in both lower extremities. In the first analysis, the CMAP or SNAP amplitude of the nerve was considered abnormal if it was less than the reference value. In the second analysis, the CMAP or SNAP amplitude of the nerve was considered abnormal if it was less than the reference value or &lt;50% of the CMAP or SNAP amplitude obtained from the intact limb nerve. Results: Thirty patients and 31 controls were included in the study. Compared with those found in the first analysis, the number of posterior tibial nerve CMAPs with reduced amplitudes, and the sural and superficial peroneal nerve SNAPs with reduced amplitudes were higher in the second analysis (P = 0.008, P &lt; 0.001, and P = 0.031; respectively). Conclusion: This study showed that nerve conduction studies should be performed in both the intact and affected extremities in SNIII.

Electrophysiological determinants of the clinical severity of axonal peripheral neuropathy.

Electrophysiological diagnosis of axonal peripheral neuropathy (PN) is based on the attenuated amplitudes of nerve conduction studies (NCS), or a reduced sural/radial amplitude ratio (SRAR). We aimed to identify the electrophysiological determinants of the clinical severity of PN. Patients with chronic axonal PN underwent detailed NCS. The clinical severity of PN was determined based upon the overall neuropathy limitations scale (ONLS). Ninety-five patients (71.6% males, mean age 71.9 ± 9.0 years) were recruited. Significant correlations were observed between the radial sensory nerve action potential (SNAP) and the ONLS total score (Spearman's rho -0.382, p < 0.001); and between the tibial compound muscle action potential and the ONLS leg score (Spearman's rho -0.283, p = 0.005). No correlations between the SRAR and the ONLS scores were found. The radial SNAP is the strongest electrophysiological determinant of PN severity and might be useful for monitoring disease progression or response to treatment. Muscle Nerve 59:491-493, 2019.

Clinical and Electrodiagnostic Features Of Nontraumatic Sciatic Neuropathy

In this study we sought to characterize etiologies and features of sciatic neuropathy unrelated to penetrating nerve trauma. This investigation was a retrospective review of 109 patients with electrodiagnostically confirmed sciatic neuropathies. Hip replacement surgery represented the most common (34.9%) etiology, whereas inflammatory sciatic neuropathy was seen in 7.3%. Electrodiagnostic testing revealed an axonal neuropathy in 95.4% and a demyelinating neuropathy in 4.6%. Predominant involvement of the peroneal division was seen in 39.4% and was tibial in 5.5%. Nine of 31 (29.0%) patients who had MRI or neuromuscular ultrasound study showed abnormalities within the sciatic nerve. At the final visit, 46.4% of patients required assistance for ambulation. Young age, lack of severe initial weakness, and presence of tibial compound muscle action potential or sural sensory nerve action potential were predictors of favorable outcome. Sciatic neuropathies are usually axonal on electrodiagnostic testing, affect preferentially the peroneal division, and are commonly associated with incomplete recovery. Muscle Nerve 59:309-314, 2019.

Monocyte-to-high density lipoprotein ratio is associated with a decreased compound muscle action potential amplitude in patients with diabetic axonal polyneuropathy.

The monocyte-to-high density lipoprotein ratio (MHR) has recently been implemented as an indicator of inflammation and oxidative stress. The present study characterized MHR in patients with diabetic polyneuropathy (DPN), in which oxidative stress and microvascular damage play a role in pathogenesis, relative to patients with non-DPN, diabetic patients without polyneuropathy, and healthy individuals. We further aimed to evaluate the association between MHR and the decreased compound muscle action potential (CMAP) amplitude of patients with diabetic axonal polyneuropathy.We enrolled 90 patients with DPN, 75 patients with nonDPN, 92 diabetic patients without polyneuropathy, and 67 healthy individuals; The monocyte, high-density lipoprotein cholesterol (HDL-C) values were obtained for all participants and MHR was calculated for each individual. Intergroup comparison was performed. The relationship between MHR and the posterior tibial nerve CMAP amplitudes was examined.Statistically significant negative correlation was observed between MHR and the posterior tibial nerve CMAP amplitudes of patients with DPN. The MHR values of the patients with DPN were significantly higher than those of the patients with non-DPN, diabetic patients without polyneuropathy and the control group.This study demonstrated that diabetic patients with higher MHR values may be more likely to develop polyneuropathy.

S79. The utility of tibial nerve SEPs in diagnosing lumbar spinal stenosis, comparison with NCS and F-Waves

Introduction Lumbar spinal stenosis (LSS) is a popular cause of lower limb motor and sensory impairments and gait disturbance. SEPs can be a tool to evaluate LSS, and there have been considerable number of studies investigating the utility of dermatomal SEP in evaluating LSS or lumbar radiculopathy. However, few studies investigated the utility of tibial nerve SEPs. Tibial nerve SEPs have an advantage that they can evaluate plural points along the whole course of the peripheral nerve and can localize the lesion site. Three segments of ankle-knee, knee-pelvis, and pelvis-spinal entry can be evaluated by N8o latency, N8o-P15 interval, and P15-N21 interval. In this study, we compared the utility of tibial nerve SEPs with nerve conduction studies (NCS) and F-waves. Methods We searched our EMG database from 2012 to 2017 with the keyword of “LSS” or “lumbar” and SEP examinations. For extracted cases, we retrospectively reviewed clinical and EMG records and MRI images. The entry criteria were as follows: (1) presence of sensory, motor, or gait (typically, intermittent claucication) complaints, (2) unequivocal LSS in lumbar MRI, (3) final diagnosis that the chief complaint was caused by the MRI-documented LSS, (4) Tibial nerve SEPs, motor conduction study (MCS) and F waves of the tibial nerve, and sensory conduction study (SCS) of the sural nerve were conducted for the same lower-limb that was the more affected, (5) no other causes that can explain his or her symptoms, especially neuropathies and diabetes, (6) no prior lumbar surgery. Results Among 39 patients initially extracted, many have been excluded by the strict inclusion criteria. Finally enrolled were 8 patients (53–82 years, all men). The clinical features of these patients were as follows. Weakness was present in 7 (absent in 1). Sensory symptoms or signs were present in 4 (absent in 4). Intermittent claucication was present in 3 patients. Tibial nerve SEPs were abnormal in 7, and could localize the lesion at the lumbar segment (P15-N21) in 6. Notably, in 3 out of 4 patients without sensory symptoms or signs, tibial nerve SEPs localized the lesion at lumbar segment. The amplitude of the compound muscle action potential (CMAP) of the tibial MCS was reduced in 2 cases, and F-wave latency was prolonged in the same 2 cases. In no cases, F-waves were abnormal despite normal SEPs. Sural SCS was normal for all cases. In two patients in which tibial nerve SEPs could not localize the lesion, needle EMG confirmed the diagnosis of LSS. Conclusion Tibial nerve SEPs are useful in diagnosing LSS by localizing the lesion at the lumbar segments. Especially the fact that they documented lumbar lesions in patients lacking sensory symptoms or signs would contribute to the differentiation from amyotrophic lateral sclerosis. The sensitivity of F-waves was much lower than tibial nerve SEPs and added no value to the amplitude of the tibial CMAP.

O-2-31. The usefulness of electrophysiological examinations in the diagnosis of tarsal tunnel syndrome

TTS is usually diagnosed based on clinical symptoms and signs, and electrodiagnostic (EDx) tests, typically nerve conduction studies. We aimed to present a case series of TTS and investigate the diagnostic role of EDx. We searched our EMG database from 2008 to 2016 with the keyword of TTS, and retrospectively reviewed clinical and EMG records of extracted patients. The entry criteria were: (1) clinical diagnosis of TTS by the referring doctor, (2) numbness of sole and a positve Tinel’s sign at the ankle, and (3) both the tibial motor conduction study (MCS) and plantar sensory conduction study (SCS) were conducted. Enrolled were 12 patients (20–82 years, 9 men and 3 women). Some EDx tests were abnormal in 8 patients. Plantar SCS was abnormal on the affected side in 5 patients. In 2 of them, tibial MCS showed a bilobed compound muscle action potential (CMAP) indicating the isolated delay of the medial plantar nerve. One patient had abnormal F wave, and 2 patients was shown denervation potentials in the FHB muscle. TTS is in general difficult to confirm electrodiagnostically, although this study supported the role of EDx. Bilobed tibial CMAP may be a previously undescribed sign of TTS.

Nerve conduction studies in lower limb of elite Nepalese football players: an insight into neural adaptations.

The study was aimed to assess somatic neural alterations in lower limbs of elite Nepalese football players by comparing their nerve conduction parameters with non-athletic controls. Players (N.=27, age 22.74±2.52 yrs.) with excellent cardio-respiratory fitness and presenting no signs of injuries, and sedentary controls (N.=29, age 23.41±2.95 yrs.) were recruited for the study. Standard nerve conduction techniques were applied to evaluate posterior tibial and sural nerves in the dominant and non-dominant limbs of each individual. Conduction velocity, onset latency, amplitude and duration of the motor and sensory evoked responses were recorded. The players had significantly lower resting mean heart rate, systolic and diastolic blood pressure than controls. Tibial compound muscle action potential (CMAP) showed higher amplitude as compared to controls; tibial proximal CMAP amplitude [(13.624±4.57) vs. (10.810±4.62) mV, P=0.035] of dominant leg, tibial proximal [(13.893±4.60) vs. (11.083±4.51) mV, P=0.045] and distal [(16.388±3.62) vs. (13.958±4.65) mV, P=0.049] amplitude of non-dominant leg. Likewise, players had significantly shorter tibial CMAPs duration of each lower limb compared with corresponding limb of controls. Sural nerve of non-dominant leg revealed shortened sensory nerve action potential duration [(1.729±0.25) vs. (1.904±0.289) ms, P=0.018]. Increased tibial CMAP amplitude and decreased CMAP duration in players suggest excitation of more number of motor units and higher synchronicity of muscle fibers' discharge than in controls respectively. Higher amplitude can also be attributed to increase in muscle fiber size and/or efficiency of neuromuscular transmission. Increased synchronicity indirectly reflects narrow range of conduction velocity among tibial neurons. The adaptive changes in somatic nerves need more crucial research for exact identification of sites and the structures responsible.

1-P-D-12. Tarsal tunnel syndrome (TTS) diagnosed by the double-peaked compound muscle action potential (CMAP) of the tibial nerve

Electrodiagnosis of tarsal tunnel syndrome (TTS) is often difficult because sensory nerve action potential (SNAP) of the planter nerves may be very small especially in aged patients and motor nerve conduction study of the tibial nerve often lacks diagnostic utility. We report a patient with TTS affecting only the medial planter nerve branch, diagnosed by the double-peaked compound muscle action potential (CMAP) of the tibial nerve. A 66 year-old woman noticed paresthesia in the medial and anterior quadrant of the sole and the planter aspects of the 1st to 3rd toes. Tinel’s sign was positive at the ankle. The tibial CMAP following ankle stimulation was double-peaked. Separate stimulation of the medial or lateral planter nerve was achieved by manipulating the stimulating electrode position at the ankle, which showed that the later peak was from the medial planter nerve. SNAP of the medial planter nerve was absent only on the affected side. An intraneural ganglion compressing the medial plantar nerve was found during operation. After surgery, her symptoms improved and the double-peaked CMAP disappeared. The double-peaked CMAP of the tibial nerve could be a finding to quickly suspect TTS affecting only the medial planter nerve.

Factors Contributing to Postural Sway in Patients with Diabetes in an In-Hospital Education Program

Objective: We investigated the effect of polyneuropathy, nephropathy, and retinopathy on postural sway in patients with poorly controlled diabetes mellitus (DM) who were hospitalized for DM education. We also investigated the relationship between postural sway and hearing disturbances. Methods: We included 50 subjects who were hospitalized for the purpose of DM education. Mean age was 57.2 years, mean HbA_1c was 9.4%, and mean DM duration was 11.1 years. Renal function, retina condition, and nerve conduction were evaluated in relation to DM complications (nephropathy, retinopathy, and neuropathy). Static posturography was performed to assess DM-related postural sway. Nerve conduction studies were used to obtain information on the condition of peripheral nerves. Pure-tone audiometry was measured. Stepwise multiple linear regression was used to assess DM-related factors that affected postural sway. Results: Deterioration of median nerve compound muscle action potential (CMAP) amplitude, tibial nerve CMAP conduction velocity, and peroneal nerve CMAP latency were associated with deterioration of postural sway. Deterioration of hearing in the worse ear was also associated with postural sway. Conclusion: In patients with poorly controlled DM, postural sway was particularly associated with deterioration of motor nerve conduction study parameters represented by median nerve CMAP amplitude, tibial nerve CMAP conduction velocity, and peroneal nerve CMAP latency. A link between diabetic polyneuropathy, diabetes-related postural sway, and diabetes-related hearing loss was recognized.

Effects of Anthropometric Factors on Nerve Conduction

Previous studies have shown that age, sex, and body mass index (BMI) affect the amplitude of sensory nerve action potentials (SNAPs), but the total effects of multiple factors and the most prominently affected nerves have not been elucidated. We systematically investigated the effects of these factors on motor and sensory nerves of the feet. The amplitude, latency, and conduction velocity of compound muscle action potential (CMAP), SNAP, and mixed nerve action potential (MNAP) of the posterior tibial, calcaneal, distal posterior tibial, medial and lateral plantar, and sural nerves were measured in 30 healthy individuals (60 feet). The effects of age, sex, height, and BMI on each nerve were estimated by correlation and linear regression analyses. The amplitude of posterior tibial CMAP and distal posterior tibial MNAP decreased with BMI. The amplitude of medial plantar MNAP and sural SNAP decreased with height. The conduction velocity of calcaneal SNAP and distal posterior tibial and lateral plantar MNAP decreased with height and BMI. The conduction velocity of medial plantar MNAP decreased only with height. The latency of posterior tibial CMAP increased with age and height. The latency of lateral plantar CMAP and calcaneal SNAP increased with height. The latency of lateral plantar MNAP increased with BMI. The effects of age, sex, height, and BMI in foot nerve conduction studies are not identical. Height and BMI were shown to strongly affect motor, sensory, and mixed nerve conduction. Further investigations are needed.

Lower Tibial Than Peroneal Compound Muscle Action Potential Amplitude in Neuromuscular Diseases

The pattern of findings on nerve conduction studies is an important component of an electrodiagnostic evaluation to assess for peripheral neuromuscular disorders. The aim of this study was to determine the extent to which a lower tibial compound muscle action potential (CMAP) amplitude compared with the peroneal CMAP amplitude is more indicative of specific neuromuscular disorders such as S1 radiculopathies, sciatic neuropathies, or peripheral neuropathies. The electromyographic (EMG) findings of 921 patients who had undergone an EMG of the lower extremity and in whom the EMG study was interpreted as normal or a single neuromuscular diagnosis was identified were retrospectively reviewed to determine the frequency of an absolutely lower tibial than peroneal CMAP amplitude. Thirty-five (7%) healthy subjects had a lower tibial than peroneal CMAP amplitude (i.e., the absolute value of the tibial CMAP was lower than the absolute value of the peroneal CMAP), despite both values being in normal range. The finding on nerve conduction study of an absolutely lower tibial than peroneal CMAP occurred in a significantly higher proportion of patients with a diffuse polyneuropathy (24%) and S1 radiculopathies (21%) compared with controls. The findings suggest that in subjects in whom lower extremity nerve conduction study demonstrates an absolutely lower tibial than peroneal CMAP amplitude, neuromuscular disorders such as a polyneuropathy or S1 radiculopathy should be considered.

Abnormal Nerve Conduction Features in Fragile X Premutation Carriers

Distal neuropathy is part of the clinical phenotype in most males with the fragile X-associated tremor/ataxia syndrome (FXTAS) caused by the 55 to 200 CGG repeat expansion. We performed nerve conduction studies in 16 male carriers with FXTAS, 11 non-FXTAS carriers, and 11 control subjects and assessed the outcomes with respect to the fragile X mental retardation 1 genotype (FMR1) (Online Mendelian Inheritance in Man [OMIM] 309550; NT011681) and messenger RNA expression. Men with FXTAS had slower tibial nerve conduction velocities and prolonged F-wave latencies compared with controls (z = 2.06, P = .04; and z = 2.73, P = .005) and unaffected premutation males (z = 1.98, P = .04; and z = 2.00, P = .04). Compound muscle action potential amplitudes were smaller in the FXTAS group relative to controls. Sural nerve action potential amplitudes were reduced in the FXTAS group compared with controls. After controlling for age, there was a significant relationship between the longer CGG repeat number and tibial nerve conduction velocity slowing (r = -0.42, P = .04) and between elevated messenger RNA levels and reduction of the tibial compound muscle action potential velocity (r = -0.52, P = .01) in the permutation group. Male premutation carriers had significant conduction abnormalities of motor and sensory nerves that correlated with molecular measures, suggesting that the premutation FMR1 genotype is a causal factor. There was also evidence of nerve conduction abnormalities in non-FXTAS carriers compared with controls, which suggests that the neuropathy can occur without the full clinical presentation of FXTAS.

Intrapartum maternal lumbosacral plexopathy.

There are many conflicting theories regarding the mechanism and prognosis of acute foot drop during labor. We report seven women who had arrested labor and foot drop. Six had short stature and one had a large newborn. All had weakness of ankle dorsiflexion, eversion, and inversion, and sensory loss in the L-5 dermatome. Superficial peroneal sensory nerve action potentials (SNAPs) were small or absent in six patients, and the sural SNAP was attenuated in one. Peroneal compound muscle action potential (CMAP) amplitude (recording from extensor digitorum brevis) was low in five, whereas the tibial CMAP was normal in all patients. Peroneal CMAP amplitude (recording from the tibialis anterior) was normal in three and small in three. Needle electromyography revealed decreased recruitment and fibrillation potentials in L-5-innervated muscles, mostly below the knee. We conclude that intrapartum foot drop occurs mostly in short women and is caused by lumbosacral trunk compression by the fetal head at the pelvic brim. The primary pathology is predominantly demyelination and recovery is complete in up to 5 months.

Electrodiagnostic changes of the lower limbs in subjects with chronic complete cervical spinal cord injury

Kirshblum S, Lim S, Garstang S, Millis S. Electrodiagnostic changes of the lower limbs in subjects with chronic complete cervical spinal cord injury. Arch Phys Med Rehabil 2001;82:604-7. Objective: To assess the electrodiagnostic changes in the lower limbs as measured by nerve conduction studies (NCSs) and electromyography in individuals with chronic complete tetraplegia. Design: Prospective testing of NCS and electromyography. Setting: Model spinal cord injury rehabilitation center. Participants: Twenty-five individuals with chronic complete tetraplegia without risk factors for peripheral neuropathy or other lower motoneuron disorders. Interventions: Nerve conduction parameters recorded from the peroneal, tibial, and sural nerves, and compared with normal values. The presence of spontaneous activity (SA), including fibrillation and positive sharp waves, recorded in 5 muscle groups—2 proximal (vastus medialis, iliopsoas), 2 distal (tibialis anterior, medial gastrocnemius), and L4 lumbar paraspinals. Analysis to see if the presence of SA correlated with the distance of the muscle from the spinal cord or with spasticity (measured by the modified Ashworth scale). Main Outcome Measures: Nerve conduction latencies and velocities; motor and sensory conduction latencies; compound muscle action potential (CMAP) and sensory nerve action potential amplitudes; spontaneous potentials: fibrillation and positive sharp waves; and spasticity. Results: NCS responses were obtained at a decreased frequency relative to able-bodied subjects. Statistically significant results in comparison to normal means included a diminished sural amplitude, and diminished peroneal and tibial CMAP and nerve conduction velocity (p <.0001). SA was recorded in at least 1 of the muscles tested in 92% of subjects, with 72% having SA in more than 1 of the muscles tested affected. A significant difference was seen for SA in the medial gastrocnemius as compared with the iliopsoas (p =.039). No correlation was noted in terms of SA with degree of spasticity. Conclusion: A statistically significant difference in NCS responses in the lower limbs in chronic tetraplegia was found relative to normal control values. However, only the frequency of responses elicited and the decreased CMAP of the peroneal nerve are clinically significant. SA was present in many of the lower extremity muscles in the subjects. Predominantly axonal changes were evident in individuals with chronic complete tetraplegia. © 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Standardized nerve conduction studies in the lower limb of the healthy elderly.

Nerve conduction studies are commonly performed in elderly individuals. No complete set of reference data for the distal lower limb nerves exists for this population, making it difficult to accurately interpret electrodiagnostic findings. The purpose of this study was to provide reliable reference data by comprehensively examining conduction characteristics in routinely tested peripheral nerves of the lower limb in a healthy elderly population. Conduction studies of the tibial, deep peroneal, sural and medial dorsal cutaneous nerves were performed in one lower limb of 122 healthy elderly individuals between the ages of 60 and 89 years. Peak amplitudes of the sural sensory action potential and the tibial compound muscle action potential correlated significantly with both age and leg length. All other parameters did not show significant correlation with age. Conduction velocities and distal latencies slowed significantly with increasing leg length except for tibial distal latency.