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Electromyography and Clinical... 1996Tarsal Tunnel Syndrome (TTS) can be difficult to diagnose: electrophysiologic corroboration is important and has therapeutic implications. Conventional electrodiagnostic...
Tarsal Tunnel Syndrome (TTS) can be difficult to diagnose: electrophysiologic corroboration is important and has therapeutic implications. Conventional electrodiagnostic techniques are insensitive: motor latency abnormalities exist in only 52%; sensory responses are frequently absent (a nonlocalizing finding). Additionally, previously described near nerve techniques do not isolate conduction velocity (CV) measurement to the short segment across the flexor retinaculum (FR), which would theoretically improve sensitivity. We describe a technique which allows for the determination of segmental sensory CVs of the medial (MP) and lateral (LP) plantar nerves, both below (BFR) and across (AFR) the FR. Seventeen normal patients (age 22-45) were studied. Near nerve recording electrodes were positioned close to the specified nerve below and above the FR. Ring electrode stimulation (RES) of digits I (MP) or V (LP) and direct near nerve stimulation (NNS) BFR were performed. With RES digit I (n = 17), mean CV (toe to BFR) was 39.0 +/- 7.1 m/s; CV (AFR) 47.9 +/- 6.2 m/s. CV (AFR) following NNS (MP) (n = 16) was 49.4 +/- 5.1 m/s. With RES digit V (n = 10), mean CV (toe to BFR) was 36.4 +/- 3.4 m/s; CV (AFR) 57.5 +/- 6.9 m/s. CV (AFR) with NNS (LP) (n = 14) was 59.8 +/- 6.2 m/s. In conclusion, segmental MP and LP sensory CVs can be reliably obtained with near nerve technique. This approach may improve the diagnostic sensitivity of EMG in TTS.
Topics: Adult; Ankle; Electromyography; Electrophysiology; Foot; Humans; Middle Aged; Neural Conduction; Sensation; Tarsal Tunnel Syndrome
PubMed: 8957166
DOI: No ID Found -
Clinical Anatomy (New York, N.Y.) Oct 2021Identification of Baxter's nerve (BN) has proven challenging for less experienced practitioners using ultrasonography due to a lack of adequate landmarks. This study...
INTRODUCTION
Identification of Baxter's nerve (BN) has proven challenging for less experienced practitioners using ultrasonography due to a lack of adequate landmarks. This study aimed to establish novel, user-friendly anatomical landmarks and to describe useful structures to localize BN.
MATERIALS AND METHODS
We examined 10 fresh cadaveric feet and identified the interobserver agreement of measuring three surface landmarks: the most medially protruded point on the medial malleolus (P), the navicular tuberosity (Q), and the center of the calcaneus (B). Next, 24 fresh cadaveric feet were used to identify the point of BN entry into the quadratus plantae (QP) muscle, which corresponds to the proximal BN impingement site. The rectangular coordinate system consisted of the origin (point P), X-axis, extension line P-Q, and Y-axis (the perpendicular line to the X-axis). To consider various foot sizes, the X and Y values were divided by the P-Q length and were designated as the ratios X and Y.
RESULTS
Points P and Q showed smaller interobserver differences than that of point B. Ratios X and Y were 61.25 and 99.80%, respectively, for the QP. BN arose from the lateral plantar nerve in 20 of 24 specimens. The adjacent vessel was <3 mm from the entrapment site of BN in 20 of 24 specimens.
CONCLUSION
New landmarks will improve the precision of localizing the entrapment site of BN and will provide advanced guidelines for podiatric patients.
Topics: Aged; Aged, 80 and over; Anatomic Landmarks; Cadaver; Female; Foot; Humans; Male; Middle Aged; Peripheral Nerves
PubMed: 33617076
DOI: 10.1002/ca.23707 -
Clinical Anatomy (New York, N.Y.) 1996Since the communicating branch of the lateral plantar nerve has been implicated as a factor in the etiology of Morton's neuroma, a painful perineurofibrosis of a common...
Since the communicating branch of the lateral plantar nerve has been implicated as a factor in the etiology of Morton's neuroma, a painful perineurofibrosis of a common plantar digital nerve, this project was designed to investigate the anatomy of this communicating branch. Both feet of 40 embalmed human cadavers were dissected to show the frequency of occurrence and anatomical variation of the communicating branch. The communicating branch was present in 66.2% of the feet we studied with no large gender-based differences. Branches occurred bilaterally in 52.5% of cadavers, while 27.5% had branches unilaterally. The occurrence of this branch does not correlate well with the likelihood of development of Morton's neuroma. Differences in diameter of the communicating branch ranged from less than 0.5 mm to as large as the common plantar digital nerves themselves, about 2 mm. The presence or absence of the communicating branch made no qualitative difference in the diameters of the common plantar digital nerves. There were 60.4% of the communicating branches in this study that had a typically-described orientation, arising more proximally in the foot from the fourth common plantar digital nerve, while 39.6% of the branches had a reversed orientation, arising more proximally from the third common plantar digital nerve. These reversed branches had a more oblique orientation when compared to the classic branches. Other anatomical variations were noted, including accessory branches that attached to deeper structures in the foot. These data form a basis for further research into the etiology of Morton's neuroma and improved surgical techniques for correcting this condition.
Topics: Adult; Female; Foot; Humans; Male; Neuroma; Peripheral Nerves; Peripheral Nervous System Diseases; Peripheral Nervous System Neoplasms; Reference Values
PubMed: 8793217
DOI: 10.1002/(SICI)1098-2353(1996)9:4<237::AID-CA4>3.0.CO;2-B -
Journal of Ultrasonography Sep 2023To present the anatomy of the tarsal tunnel and demonstrate the utility of high-resolution ultrasound for tarsal tunnel examination.
AIM OF THE STUDY
To present the anatomy of the tarsal tunnel and demonstrate the utility of high-resolution ultrasound for tarsal tunnel examination.
MATERIALS AND METHODS
Anatomical dissection was performed on a defrosted cadaveric model to demonstrate relevant anatomical structures of the tarsal tunnel, namely tendons, vessels and nerves. The tibial nerve division was demonstrated; the bifurcation of the tibial nerve into the medial and lateral plantar nerve, two medial calcaneal nerve branches were identified originating from the tibial nerve and the Baxter's nerve was identified as the first branch of the lateral plantar nerve. An ultrasound examination of the tarsal tunnel region was performed on a healthy volunteer. A linear probe was used and sonographic images were obtained at different levels of the tarsal tunnel: the proximal tarsal tunnel, the tibial nerve division into the medial and lateral plantar nerves, the distal tarsal tunnel, the Baxter's nerve branching point and the Baxter's nerve crossing between the abductor hallucis and quadratus plantae muscle.
RESULTS
Sonographic images were correlated with anatomical structures exposed during cadaveric dissection.
CONCLUSIONS
We presented the anatomic-sonographic correlation of the tarsal tunnel and showed that high-resolution ultrasound is a useful imaging modality for tarsal tunnel assessment.
PubMed: 37701055
DOI: 10.15557/jou.2023.0023 -
Clinics in Sports Medicine Apr 1990Although neuropathies in the athlete's foot and ankle are uncommon, they are often underdiagnosed. This is primarily due to the complex interplay of factors that are... (Review)
Review
Although neuropathies in the athlete's foot and ankle are uncommon, they are often underdiagnosed. This is primarily due to the complex interplay of factors that are required for their presentation. The most frequently encountered entrapment syndromes (in decreasing order) involve the interdigital nerves, first branch of the lateral plantar nerve, isolated medial or lateral plantar nerves, posterior tibial nerve, deep peroneal nerve, superficial peroneal nerve, sural nerve, and saphenous nerve. A thorough knowledge of peripheral nerve anatomy is essential in establishing the diagnosis. Roentgenograms may reveal bony abnormalities that are the diagnosis. Roentgenograms may reveal bony abnormalities that are commonly contributory. Electrodiagnostic tests may be normal because these dynamic syndromes often resolve at rest. In most cases, correction of underlying etiologies combined with rest, NSAIDs, and occasionally injections will allow resolution of the syndrome. Recalcitrant cases may require surgical decompression, which frequently provides satisfactory results.
Topics: Adult; Ankle; Diagnosis, Differential; Female; Foot; Humans; Male; Nerve Compression Syndromes; Peripheral Nerves; Peroneal Nerve; Sports Medicine; Tibial Nerve
PubMed: 2183956
DOI: No ID Found -
Annual International Conference of the... Jul 2020Many advances have been made with imaging of implanted neural devices; however, the ability to image whole nerve samples remains limited. Further, few imaging modalities...
Many advances have been made with imaging of implanted neural devices; however, the ability to image whole nerve samples remains limited. Further, few imaging modalities are well suited for visualizing both whole devices in vivo and individual microelectrodes within a nerve. In this study, we used micro-computed tomography (micro-CT) to evaluate Wireless Floating Microelectrode Arrays (WMFAs) implanted in rat sciatic nerve at the level of whole devices and individual electrodes. WFMAs were also used to track selective recruitment of plantar flexion and dorsiflexion of the rear paw, which was achieved by each implanted device (n=6) during chronic implantation. Evoked limb motion was correlated to end-of-study assessments using micro-CT to visualize electrode locations within the fascicular structure of the sciatic nerve. Results of this study show that micro-CT imaging can provide valuable assessments of microelectrode arrays implanted in peripheral nerves for both whole devices visualized in vivo and individual electrodes visualized in whole nerve tissue samples.Clinical relevance- This work informs the use of micro-computed tomography as a tool for correlating neural device performance with physical attributes of the implant location.
Topics: Animals; Electrodes, Implanted; Microelectrodes; Rats; Sciatic Nerve; X-Ray Microtomography
PubMed: 33018741
DOI: 10.1109/EMBC44109.2020.9176598 -
Folia Morphologica 2021The purpose of this study was to evaluate the topographic anatomy of the tibial nerve and its medial calcaneal branches in relation to the tip of the medial malleolus...
BACKGROUND
The purpose of this study was to evaluate the topographic anatomy of the tibial nerve and its medial calcaneal branches in relation to the tip of the medial malleolus and to the posterior superior tip of the calcaneal tuberosity using the ultrasound examination and to verify its preoperative usefulness in surgical treatment.
MATERIALS AND METHODS
Bilateral ultrasound examination was performed on 30 volunteers and the location of the tibial nerve bifurcation and medial calcaneal branches origin were measured. Medial calcaneal branches were analysed in reference to the amount and their respective nerves of origin.
RESULTS
In 77% of cases, tibial nerve bifurcation occurred below the tip of the medial malleolus with the average distance of 5.9 mm and in 48% of cases above the posterior superior tip of the calcaneal tuberosity with the average distance of 2.7 mm. In 73% of cases medial calcaneal branches occurred as a single branch originating from the tibial nerve (60%). The average distance of the first, second and third medial calcaneal branch was accordingly 9.3 mm above, 9.5 mm below and 11.6 mm below the tip of the medial malleolus and 17.7 mm above, 1.6 mm below and 4 mm below the posterior superior tip of the calcaneal tuberosity.
CONCLUSIONS
As the tibial nerve and its branches present a huge variability in the medial ankle area, in order to prevent the iatrogenic injuries, the preoperative or intraoperative ultrasound assessment (sonosurgery) of its localisation should be introduced into the clinic.
Topics: Cadaver; Calcaneus; Humans; Tibial Nerve; Ultrasonography; Ultrasonography, Interventional
PubMed: 32488855
DOI: 10.5603/FM.a2020.0062 -
Clinical Anatomy (New York, N.Y.) Oct 2019The relationship between the plantar nerves and internal fascial structure of the calcaneal tunnel is clinically important to alleviate pain of the sole. The study aimed...
The relationship between the plantar nerves and internal fascial structure of the calcaneal tunnel is clinically important to alleviate pain of the sole. The study aimed to investigate the three-dimensional (3D) anatomy of the calcaneal tunnel and its internal fascial septal structure by using microcomputed tomography (mCT) with a phosphotungstic acid preparation, histologic examination, and ultrasound-guided simulation. Twenty-one fixed cadavers and three fresh-frozen cadavers (13 men and 11 women, mean age 82.1 years at death) were used in this study. The 3D images of the calcaneal tunnel harvested by mCT were analyzed in detail. Modified Masson trichrome staining and serial sectional dissection after ultrasound-guided injection were conducted to verify the 3D anatomy. Within the calcaneal tunnel, the interfascicular septum (IFS) commenced proximal to the malleolar-calcaneal line and distal to the bifurcation of the tibial nerve into the plantar nerves. The medial and lateral plantar nerves were separated by the IFS, which divided the calcaneal tunnel into two compartments. The plantar nerves were ramified into two or three branches within each compartment. The IFS terminated around the talocalcaneonavicular joint, and the plantar nerves traveled into the sole. Clinical manipulation of the plantar nerves should be performed in consideration of the fact that they are clearly separated by the IFS. Clin. Anat. 32:877-882, 2019. © 2019 Wiley Periodicals, Inc.
Topics: Aged, 80 and over; Cadaver; Calcaneus; Dissection; Fascia; Female; Foot; Humans; Imaging, Three-Dimensional; Male; Tibial Nerve
PubMed: 30945342
DOI: 10.1002/ca.23381 -
The Journal of Comparative Neurology Nov 1987In the rat, the numbers and locations of motoneurons innervating the short plantar muscles of the hindlimb (supplied by the medial and lateral plantar nerves, as well as...
In the rat, the numbers and locations of motoneurons innervating the short plantar muscles of the hindlimb (supplied by the medial and lateral plantar nerves, as well as a branch of the sural nerve) were determined by using both horseradish peroxidase (HRP) and fluorochromes as retrograde labels. Topographical organization within the plantar motor nucleus was examined by exposing individually the cut ends (encapsulated in low melting-point paraffin) of medial plantar, lateral plantar, and sural nerves to HRP. In addition, double-labeling experiments were conducted in which the medial plantar nerve was labeled with one fluorochrome (either true blue or diamidino yellow) and the lateral plantar nerve with another. The plantar motor pool is located in the extreme dorsolateral portion of the ventral horn, usually concentrated in the fifth lumbar (L5) spinal segment. Labeled motoneurons extended caudally into the sixth lumbar (L6) segment and rostrally into portions of the fourth lumber (L4) segment. Motoneurons of the medial plantar, lateral plantar, and sural nerve have overlapping territories. Sural motoneurons (about 70 cells per side) are generally confined to L5, medial plantar motoneurons (about 180 cells per side) tend to be concentrated in caudal L5 and rostral L6, whereas the lateral plantar motoneurons (about 310 cells per side) extend throughout the entire length of the plantar motor pool. The distribution of motoneuronal cell size is unimodal (mean cross-sectional area = 610 +/- 150 microns2). Cell bodies of plantar motoneurons tend to have similar geometries in all three major planes of sectioning. In all, the combined plantar plus sural nerve population amounts to about 560 motoneurons on each side of the spinal cord. On the basis of these data, and those published by others, the innervation of the small muscles of the foot accounts for about 25% of the motor axons carried by the entire sciatic nerve.
Topics: Animals; Cell Count; Fluorescent Dyes; Hindlimb; Histocytochemistry; Horseradish Peroxidase; Male; Motor Neurons; Muscles; Rats; Rats, Inbred Strains
PubMed: 3693601
DOI: 10.1002/cne.902650108 -
Journal of Diabetes and Metabolic... Jun 2021Diabetes mellitus is amongst the most common causes of polyneuropathy worldwide that can eventually terminate to irreversible complications. The remarkable impact of...
PURPOSE
Diabetes mellitus is amongst the most common causes of polyneuropathy worldwide that can eventually terminate to irreversible complications. The remarkable impact of diabetic polyneuropathy as a debilitating condition on the healthcare system and total costs of diabetes care is undeniable. Despite the existence of numerous diagnostic tools such as routine electrophysiologic procedures, its early detection is challenging. This study designed to compare more distal techniques of electrodiagnostic testing, including interdigital sensory nerve conduction studies (NCSs), with conventional approaches and to investigate its role in confirming the early stages of polyneuropathy.
METHODS
This cross-sectional study was performed in the Physical Medicine and Rehabilitation Department of Hazrat Fatemeh Reconstruction Surgery Hospital. Thirty one symptomatic diabetic outpatients and 23 asymptomatic nondiabetic subjects included in our study. We performed nerve conduction studies on five sensory nerves consist of the dorsal sural nerve, medial plantar nerve, digital branches of the interdigital nerves to toes I, II, and III (as a new antidromic technique). In this study, all techniques applied with a surface stimulator and pick-up electrodes.
RESULTS
In the group of patients, 9 (29%) and 22 (71%) subjects had impaired and normal routine NCSs, respectively. Interestingly, the results of interdigital nerve studies were abnormal in the 17 out of 22 patients with normal routine NCSs. Also, 11 and 13 subjects had impaired medial plantar nerve and dorsal sural nerve conduction studies, respectively. Accordingly, with this new method, the prevalence of detectable diabetic neuropathy increased from 46% to 83%.
DISCUSSION
We conducted this study intending to demonstrate the application of a new technique for early diagnosis of diabetic polyneuropathy, especially in the presymptomatic and subclinical neuropathies. The digital sensory branches of IDNs known as the most distal sensory nerves, which can be easily evaluated with new antidromic SNAP technique. Our method is simple, non-invasive, suitable, sensitive, and reproducible. There is no need to needle electrode or averaging technique to record an appropriate amplitude of IDN. Thus, it is recommended as a convenient electrophysiological option for early diagnosis of DPN.
PubMed: 34178823
DOI: 10.1007/s40200-020-00710-1