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The Journal of International Medical... Oct 2019Reconstruction of soft tissue defects in the foot and ankle remains challenging. This study was performed to investigate the technical points and clinical effects of a...
OBJECTIVE
Reconstruction of soft tissue defects in the foot and ankle remains challenging. This study was performed to investigate the technical points and clinical effects of a double-pedicle propeller flap for repair of foot and ankle soft tissue defects.
METHODS
We used five fresh calf specimens to investigate the anatomical and operative aspects of a double-pedicle propeller flap. Eighteen patients with soft tissue defects in the foot and ankle subsequently underwent defect repair with double-pedicle propeller flaps.
RESULTS
The anatomical study showed that the peroneal artery perforators and the sural nerve bundle (two blood supply systems) provided the theoretical anatomical basis for the double-pedicle propeller flap. The relative positions of the peroneal artery perforators and the sural nerve bundle differ according to the peroneal artery perforating level. Flap rotation in different directions can reduce or prevent the pedicles from compressing each other. All flaps survived, and three flaps developed local epidermal necrosis at the proximal end; these flaps healed after 1 to 2 weeks of dressing changes. The other 15 patients healed well.
CONCLUSIONS
The double-pedicle propeller flap can enhance the blood supply and venous return in the “big paddle” region of the flap, reducing the distal necrosis rate.
Topics: Adolescent; Adult; Aged; Ankle; Child; Child, Preschool; Female; Foot; Humans; Male; Middle Aged; Sural Nerve; Surgical Flaps; Young Adult
PubMed: 31378112
DOI: 10.1177/0300060519865625 -
Journal of Neurology, Neurosurgery, and... Jun 1974Using surface electrodes, sensory nerve action potentials (SAP) have been recorded in the proximal segment (mid-calf to lateral malleolus) and the distal segment...
Using surface electrodes, sensory nerve action potentials (SAP) have been recorded in the proximal segment (mid-calf to lateral malleolus) and the distal segment (lateral malleolus to toe 5) of the sural nerve and in the median nerve in 79 control subjects. The values obtained for the distal segment of the sural nerve varied widely and in seven apparently normal subjects no SAP could be distinguished. In the proximal segment conduction velocities were over 40 m/s and there was no significant change with age, unlike the median nerve in which a highly significant slowing occurred with age. Comparison of the results of sural and median sensory conduction studies in 300 consecutive patients screened for sensory polyneuropathy confirms the value of sural nerve sensory studies as a routine screening test, and confirms the belief that the changes in polyneuropathy are usually more prominent in lower limb nerves. It is therefore suggested that studies of sural sensory conduction form the single most useful test in the diagnosis of sensory polyneuropathy.
Topics: Adolescent; Adult; Age Factors; Aged; Carpal Tunnel Syndrome; Child; Evoked Potentials; Female; Humans; Leg; Male; Median Nerve; Middle Aged; Neural Conduction; Neuritis; Peripheral Nervous System Diseases; Spinal Nerves; Sural Nerve
PubMed: 4367408
DOI: 10.1136/jnnp.37.6.647 -
Journal of Neurology, Neurosurgery, and... Jan 1998To investigate the additional diagnostic value of sural nerve biopsy of 64 patients in whom chronic inflammatory demyelinating polyneuropathy (CIDP) was considered, as...
OBJECTIVE
To investigate the additional diagnostic value of sural nerve biopsy of 64 patients in whom chronic inflammatory demyelinating polyneuropathy (CIDP) was considered, as sural nerve biopsy is recommended in the research criteria of an ad hoc subcommittee to diagnose CIDP.
METHODS
Firstly, the additional diagnostic value of sural nerve biopsy was analysed with multivariate logistic regression. Six clinical features (remitting course, symmetric sensorimotor neuropathy in arms and legs, areflexia, raised CSF protein concentration, nerve conduction studies consistent with demyelination, and absence of comorbidity or relevant laboratory abnormalities) were entered into a logistic model. Afterwards, all significant features identified from this model, as well as the results of sural nerve biopsy were forced into a second logistic model. Secondly, the diagnostic performance of a neurologist experienced in diagnosis of peripheral nerve disorders was studied by receiver operating characteristics (ROC) curve analysis.
RESULTS
The results of the first logistic analysis showed that CSF protein concentration >1 g/l (odds ratio (OR)=38.5) and neurophysiological studies consistent with demyelination (OR=51.7) were strong predictors of CIDP. When forcing the significant features and the sural nerve biopsy data into the model, an independent predictive value of sural nerve biopsy could not be found. The neurologist was able to discriminate patients with and without CIDP (area under the curve (AUC)=0.95). His diagnostic performance did not improve significantly by offering him the results of sural nerve biopsy.
CONCLUSION
Any additional diagnostic value of sural nerve biopsy in the diagnosis of CIDP could not be shown.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biopsy; Cerebrospinal Fluid Proteins; Child; Chronic Disease; Demyelinating Diseases; Diagnosis, Differential; Discriminant Analysis; Electrophysiology; Female; Follow-Up Studies; Humans; Logistic Models; Male; Middle Aged; Motor Neuron Disease; Multivariate Analysis; Polyradiculoneuropathy; Reproducibility of Results; Sensitivity and Specificity; Sural Nerve
PubMed: 9436733
DOI: 10.1136/jnnp.64.1.84 -
The Journal of Physiology Feb 19981. The functions of ipsilateral cutaneous reflexes were studied with short trains of stimuli presented pseudorandomly to the sural nerve during human walking....
1. The functions of ipsilateral cutaneous reflexes were studied with short trains of stimuli presented pseudorandomly to the sural nerve during human walking. Electromyograms (EMG) of lower (tibialis anterior (TA), soleus, lateral (LG) and medial (MG) gastrocnemius) and upper leg (vastus lateralis and biceps femoris) muscles were recorded, together with ankle, knee and hip joint angles. Net reflex EMG responses were quantified in each of the sixteen parts of the step cycle. The kinematic measurements included ankle eversion- inversion, and ankle, knee and hip flexion-extension. 2. The function of the sural reflexes depended upon the part of the step cycle in which the nerve was stimulated and the intensity of stimulation. During stance, reflexes in MG and TA muscles in response to a medium intensity of stimulation (1.9 x radiating threshold, x RT) were closely associated with ankle eversion and dorsiflexion responses, respectively. These responses could assist in accommodation to uneven terrain that applies pressure to the lateral side of the foot (sural innervation area). Non-noxious, high intensity (2.3 x RT) stimulation resulted in strong suppression of LG and MG during stance which was correlated to a small reduction in ankle plantarflexion. At this higher intensity the response would function to prevent the foot from moving more forcefully onto a potentially harmful obstacle. 3. During swing, ankle dorsiflexion increased and was significantly correlated to the net TA EMG response after both medium and high intensity stimulation. Knee flexion was increased throughout swing at both intensities of stimulation. These responses may serve in an avoidance response in which the swing limb is brought past an obstacle without destabilizing contact. 4. The net EMG and kinematic responses suggest that cutaneous reflexes stabilize human gait against external perturbations produced by an uneven surface in stance or obstacles encountered during swing.
Topics: Adult; Electric Stimulation; Electromyography; Female; Humans; Leg; Male; Middle Aged; Reflex; Sural Nerve; Thigh; Walking
PubMed: 9490858
DOI: 10.1111/j.1469-7793.1998.305bu.x -
Ulusal Travma Ve Acil Cerrahi Dergisi =... Mar 2013The sciatic and peroneal nerves are the most frequently injured in lower extremities, followed by tibial and femoral nerves. The aim of this study is to evaluate the...
BACKGROUND
The sciatic and peroneal nerves are the most frequently injured in lower extremities, followed by tibial and femoral nerves. The aim of this study is to evaluate the functional results of acute nerve grafting in traumatic sciatic nerve injuries.
METHODS
A total of 9 patients with sciatic nerve defect were treated with primary nerve grafting. The mean age was 31.7 years. The etiologic factors were gunshot wounds, traffic accident, and penetrating trauma.
RESULTS
All of the patients had sciatic nerve defects ranging from 3.4 to 13.6 cm. The follow-up period ranged between 25 and 84 months. The tibial nerve motor function was "good" or "very good" (M3-M4) in 5 patients (55.6%). The plantar flexion was not sufficient for the rest of the patients. The peroneal nerve motor function was also "good" and "very good" in 3 patients (33.3%).
CONCLUSION
The functional results of the acute nerve grafting of the sciatic nerve within the first week after the injury are poorer than reported in the related literature. This protocol should only be applied to select patients who have adequate soft tissue coverage and healthy nerve endings.
Topics: Adult; Female; Humans; Male; Peripheral Nerve Injuries; Retrospective Studies; Sciatic Nerve; Sural Nerve; Treatment Outcome; Young Adult
PubMed: 23599192
DOI: 10.5505/tjtes.2013.33279 -
Journal of Neurology, Neurosurgery, and... Jun 1999To assess the extent of loss of myelinated nerve fibres and spinal motor neuron loss in chronic inflammatory demyelinating polyneuropathy (CIDP), a clinicopathological...
OBJECTIVES
To assess the extent of loss of myelinated nerve fibres and spinal motor neuron loss in chronic inflammatory demyelinating polyneuropathy (CIDP), a clinicopathological study was conducted on biopsied sural nerves and necropsied spinal cords from patients with CIDP.
METHODS
The myelinated fibre pathology of 71 biopsied sural nerves and motor neuron pathology of nine necropsied spinal cords at L4 levels in patients with CIDP were quantitatively and immunohistochemically assessed.
RESULTS
Myelinated nerve fibre density was significantly diminished to 65.4% of the control values (p <0.0001), correlating inversely with the extent of segmental demyelination and remyelination (r = -0.43, p < 0.0005) and duration of illness (r = -0.31, p < 0.01). Numbers of large spinal motor neurons in CIDP were variably but significantly diminished (range from 46.0 to 97.6% of the age matched control value (p < 0.005)), and reactive astrogliosis was evident in the ventral horn in CIDP. The frequency of ventral horn neurons exhibiting central chromatolysis and the accumulation of phosphorylated high molecular weight neurofilament protein was significantly higher in CIDP than in controls (p<0.01 and p<0.05).
CONCLUSIONS
The loss of nerve axons and spinal motor neurons is common in CIDP, and extensive in some cases. These neuronal and axonal losses may influence the functional prognosis in CIDP.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Demyelinating Diseases; Female; Humans; Inflammation; Male; Middle Aged; Peripheral Nervous System Diseases; Spinal Cord; Sural Nerve
PubMed: 10329744
DOI: 10.1136/jnnp.66.6.727 -
Neurology India 2010According to American Academy of Neurology (AAN) criteria, demonstration of demyelination in the sural nerve by teased fiber or ultrastructure is considered mandatory...
BACKGROUND
According to American Academy of Neurology (AAN) criteria, demonstration of demyelination in the sural nerve by teased fiber or ultrastructure is considered mandatory for diagnosis of chronic inflammatory demyelinating polyneuropathies (CIDP). In resource-restricted settings where these techniques are not freely available, it is useful to determine the utility of 'supportive' pathologic criteria (subperineurial edema, inflammation, onion bulb formation, and demyelination) proposed by AAN for diagnosis of CIDP.
SETTINGS AND DESIGN
Tertiary care hospital, retrospective study.
PATIENTS AND METHODS
Forty-six patients with idiopathic CIDP (32 with progressive course and 14 with relapsing-remitting course) satisfying AAN clinical and electrophysiologic criteria evaluated between January 1991 and August 2004 were reviewed. Frequency of specific pathological alterations such as demyelination, inflammation, onion bulb formation, and axonal changes in sural nerve biopsies was evaluated. Statistical Analysis : SPSS statistical package was used to calculate mean, range, and standard deviation. Student's t test, chi-square test, and ANOVA were used for determining statistical significance.
RESULTS AND CONCLUSION
Reduction in myelinated fiber density was most frequent (93.5%), followed by demyelination (82.8%), inflammation (58.7%), and onion bulb formation (28.3%). Endoneurial inflammation was frequent in the relapsing-remitting form and epineurial inflammation and axonal changes in those with progressive course. Greater disability at presentation, poor response to immunomodulation, and lower CSF protein levels was seen in those with axonal pathology. Pathological abnormalities were demonstrable in all (100%), whereas electrophysiological abnormalities were detected in 90.8%, suggesting that supportive histologic AAN criteria are helpful in diagnosis of CIDP.
Topics: Adolescent; Adult; Aged; Biopsy; Child; Child, Preschool; Female; Humans; Male; Middle Aged; Polyradiculoneuropathy, Chronic Inflammatory Demyelinating; Retrospective Studies; Sural Nerve; Young Adult
PubMed: 20739789
DOI: 10.4103/0028-3886.68673 -
Diabetes Sep 2015To define the components of the metabolic syndrome that contribute to diabetic polyneuropathy (DPN) in type 2 diabetes mellitus (T2DM), we treated the BKS db/db mouse,...
To define the components of the metabolic syndrome that contribute to diabetic polyneuropathy (DPN) in type 2 diabetes mellitus (T2DM), we treated the BKS db/db mouse, an established murine model of T2DM and the metabolic syndrome, with the thiazolidinedione class drug pioglitazone. Pioglitazone treatment of BKS db/db mice produced a significant weight gain, restored glycemic control, and normalized measures of serum oxidative stress and triglycerides but had no effect on LDLs or total cholesterol. Moreover, although pioglitazone treatment normalized renal function, it had no effect on measures of large myelinated nerve fibers, specifically sural or sciatic nerve conduction velocities, but significantly improved measures of small unmyelinated nerve fiber architecture and function. Analyses of gene expression arrays of large myelinated sciatic nerves from pioglitazone-treated animals revealed an unanticipated increase in genes related to adipogenesis, adipokine signaling, and lipoprotein signaling, which likely contributed to the blunted therapeutic response. Similar analyses of dorsal root ganglion neurons revealed a salutary effect of pioglitazone on pathways related to defense and cytokine production. These data suggest differential susceptibility of small and large nerve fibers to specific metabolic impairments associated with T2DM and provide the basis for discussion of new treatment paradigms for individuals with T2DM and DPN.
Topics: Animals; Cholesterol; Diabetes Mellitus, Type 2; Diabetic Neuropathies; Disease Models, Animal; Hypoglycemic Agents; Lipoproteins, LDL; Metabolic Syndrome; Mice; Nerve Fibers, Myelinated; Nerve Fibers, Unmyelinated; Neural Conduction; Oxidative Stress; Pioglitazone; Sciatic Nerve; Sural Nerve; Thiazolidinediones; Triglycerides; Weight Gain
PubMed: 25979075
DOI: 10.2337/db15-0133 -
The Tohoku Journal of Experimental... Dec 1979Sural nerve lesions in patients with clinically manifest diabetic neuropathy were investigated electron microscopically. Myelinated nerve fibers were reduced in all the...
Sural nerve lesions in patients with clinically manifest diabetic neuropathy were investigated electron microscopically. Myelinated nerve fibers were reduced in all the diabetic patients. Axonal degeneration of both myelinated and unmyelinated nerve fibers was most conspicuous finding in the diabetic sural nerves. Structural changes of the axons were represented by axonal dwindling, depletion of axoplasmic organelles, vacuolarization and an increase in neurofilaments. Accumulation of glycogen-like particles and deposition of electron homogeneous amorphous materials were noted within a few axons. On the other hand, there could also be found degenerative changes of myelin sheaths, various kinds of cytoplasmic inclusion bodies (crystalloid, lamellar inclusion bodies and lipids-like droplets), aggregates of glycogen particles in the Schwann cell cytoplasm and basement membrane hyperplasia of Schwann cells in all the subjects. Furthermore, multiplication and thickening of the basement membrane of vasa nervorum were constant findings of the diabetic sural nerves. The vascular changes, demyelination and axonal degeneration of the cases were not apparently correlated with each other. There was no special relationship between nerve tissue changes and clinical symptoms or laboratory findings. These results indicated that the peripheral nerve lesions in human diabetics were mainly due to metabolic impairment of nerve fibers, accompanying dysmetabolism of Schwann cells and diabetic microangiopathy, and that these changes proceeded independently.
Topics: Adult; Axons; Diabetic Neuropathies; Humans; Male; Middle Aged; Myelin Sheath; Spinal Nerves; Sural Nerve
PubMed: 524360
DOI: 10.1620/tjem.129.357 -
The Journal of Physiology Mar 2017Trans-spinal polarization was recently introduced as a means to improve deficient spinal functions. However, only a few attempts have been made to examine the mechanisms...
KEY POINTS
Trans-spinal polarization was recently introduced as a means to improve deficient spinal functions. However, only a few attempts have been made to examine the mechanisms underlying DC actions. We have now examined the effects of DC on two spinal modulatory systems, presynaptic inhibition and post-activation depression, considering whether they might weaken exaggerated spinal reflexes and enhance excessively weakened ones. Direct current effects were evoked by using local intraspinal DC application (0.3-0.4 μA) in deeply anaesthetized rats and were compared with the effects of trans-spinal polarization (0.8-1.0 mA). Effects of local intraspinal DC were found to be polarity dependent, as locally applied cathodal polarization enhanced presynaptic inhibition and post-activation depression, whereas anodal polarization weakened them. In contrast, both cathodal and anodal trans-spinal polarization facilitated them. The results suggest some common DC-sensitive mechanisms of presynaptic inhibition and post-activation depression, because both were facilitated or depressed by DC in parallel.
ABSTRACT
Direct current (DC) polarization has been demonstrated to alleviate the effects of various deficits in the operation of the central nervous system. However, the effects of trans-spinal DC stimulation (tsDCS) have been investigated less extensively than the effects of transcranial DC stimulation, and their cellular mechanisms have not been elucidated. The main objectives of this study were, therefore, to extend our previous analysis of DC effects on the excitability of primary afferents and synaptic transmission by examining the effects of DC on two spinal modulatory feedback systems, presynaptic inhibition and post-activation depression, in an anaesthetized rat preparation. Other objectives were to compare the effects of locally and trans-spinally applied DC (locDC and tsDCS). Local polarization at the sites of terminal branching of afferent fibres was found to induce polarity-dependent actions on presynaptic inhibition and post-activation depression, as cathodal locDC enhanced them and anodal locDC depressed them. In contrast, tsDCS modulated presynaptic inhibition and post-activation depression in a polarity-independent fashion because both cathodal and anodal tsDCS facilitated them. The results show that the local presynaptic actions of DC might counteract both excessively strong and excessively weak monosynaptic actions of group Ia and cutaneous afferents. However, they indicate that trans-spinally applied DC might counteract the exaggerated spinal reflexes but have an adverse effect on pathologically weakened spinal activity by additional presynaptic weakening. The results are also relevant for the analysis of the basic properties of presynaptic inhibition and post-activation depression because they indicate that some common DC-sensitive mechanisms contribute to them.
Topics: Animals; Electric Stimulation; Female; Male; Peroneal Nerve; Rats, Wistar; Spinal Cord; Sural Nerve; Synaptic Transmission
PubMed: 27891626
DOI: 10.1113/JP272902