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Insights Into Imaging Oct 2023Peripheral nerves of the lower limb may become entrapped at various points during their anatomical course. While clinical assessment and nerve conduction studies are the... (Review)
Review
Peripheral nerves of the lower limb may become entrapped at various points during their anatomical course. While clinical assessment and nerve conduction studies are the mainstay of diagnosis, there are multiple imaging options, specifically ultrasound and magnetic resonance imaging (MRI), which offer important information about the potential cause and location of nerve entrapment that can help guide management. This article overviews the anatomical course of various lower limb nerves, including the sciatic nerve, tibial nerve, medial plantar nerve, lateral plantar nerve, digital nerves, common peroneal nerve, deep peroneal nerve, superficial peroneal nerve, sural nerve, obturator nerve, lateral femoral cutaneous nerve and femoral nerve. The common locations and causes of entrapments for each of the nerves are explained. Common ultrasound and MRI findings of nerve entrapments, direct and indirect, are described, and various examples of the more commonly observed cases of lower limb nerve entrapments are provided.Critical relevance statement This article describes the common sites of lower limb nerve entrapments and their imaging features. It equips radiologists with the knowledge needed to approach the assessment of entrapment neuropathies, which are a critically important cause of pain and functional impairment.Key points• Ultrasound and MRI are commonly used to investigate nerve entrapment syndromes.• Ultrasound findings include nerve hypo-echogenicity, calibre changes and the sonographic Tinel's sign.• MRI findings include increased nerve T2 signal, muscle atrophy and denervation oedema.• Imaging can reveal causative lesions, including scarring, masses and anatomical variants.
PubMed: 37782348
DOI: 10.1186/s13244-023-01514-6 -
Journal of Nippon Medical School =... 2024Tarsal tunnel syndrome (TTS) is a common entrapment neuropathy that is sometimes elicited by ganglia in the tarsal tunnel.
BACKGROUND
Tarsal tunnel syndrome (TTS) is a common entrapment neuropathy that is sometimes elicited by ganglia in the tarsal tunnel.
METHODS
Between August 2020 and July 2022, we operated on 117 sides with TTS. This retrospective study examined data from 8 consecutive patients (8 sides: 5 men, 3 women; average age 67.8 years) with an extraneural ganglion in the tarsal tunnel. We investigated the clinical characteristics and surgical outcomes for these patients.
RESULTS
The mass was palpable through the skin in 1 patient, detected intraoperatively in 1 patient, and visualized on MRI scanning in the other 6 patients. Symptoms involved the medial plantar nerve area (n = 5), lateral plantar nerve area (n = 1), and medial and lateral plantar nerve areas (n = 2). The interval between symptom onset and surgery ranged from 4 to 168 months. Adhesion between large (≥20 mm) ganglia and surrounding tissue and nerves was observed intraoperatively in 4 patients. Of the 8 patients, 7 underwent total ganglion resection. There were no surgery-related complications. On their last postoperative visit, 3 patients with a duration of symptoms not exceeding 10 months reported favorable outcomes.
CONCLUSIONS
Because ganglia eliciting TTS are often undetectable by skin palpation, imaging studies may be necessary. Early surgical intervention appears to yield favorable outcomes.
Topics: Male; Humans; Female; Aged; Tarsal Tunnel Syndrome; Retrospective Studies; Magnetic Resonance Imaging; Skin
PubMed: 38462440
DOI: 10.1272/jnms.JNMS.2024_91-203 -
Journal of Ultrasonography Sep 2023Plantar intrinsic muscles play a pivotal role in posture control and gait dynamics. They help maintain the longitudinal and transverse arches of the foot, and they...
Plantar intrinsic muscles play a pivotal role in posture control and gait dynamics. They help maintain the longitudinal and transverse arches of the foot, and they regulate the degree and velocity of arch deformation during walking or running. Consequently, pathologies affecting the plantar intrinsic muscles (for instance, acquired and inherited neuropathies) lead to foot deformity, gait disorders, and painful syndromes. Intrinsic muscle malfunctioning is also associated with multifactorial overuse or degenerative conditions such as pes planus, hallux valgus, and plantar fasciitis. As the clinical examination of each intrinsic muscle is challenging, ultrasound is gaining a growing interest as an imaging tool to investigate the trophism of these muscular structures and the pattern of their alterations, and potentially to follow up on the effects of dedicated rehabilitation protocols. The ten plantar intrinsic muscles can be dived into three groups (medial, central and lateral) and four layers. Here, we propose a regional and landmark-based approach to the complex sonoanatomy of the plantar intrinsic muscles in order to facilitate the correct identification of each muscle from the superficial to the deepest layer. We also summarize the pathological ultrasound findings that can be encountered when scanning the plantar muscles, pointing out the patterns of alterations specific to certain conditions, such as plantar nerves mononeuropathies.
PubMed: 37732108
DOI: 10.15557/jou.2023.0024 -
Biosensors Aug 2023Some chronic diseases, including Parkinson's disease (PD), diabetic foot, flat foot, stroke, elderly falling, and knee osteoarthritis (KOA), are related to orthopedic... (Review)
Review
Some chronic diseases, including Parkinson's disease (PD), diabetic foot, flat foot, stroke, elderly falling, and knee osteoarthritis (KOA), are related to orthopedic organs, nerves, and muscles. The interaction of these three parts will generate a comprehensive result: gait. Furthermore, the lesions in these regions can produce abnormal gait features. Therefore, monitoring the gait features can assist medical professionals in the diagnosis and analysis of these diseases. Nowadays, various insole systems based on different sensing techniques have been developed to monitor gait and aid in medical research. Hence, a detailed review of insole systems and their applications in disease management can greatly benefit researchers working in the field of medical engineering. This essay is composed of the following sections: the essay firstly provides an overview of the sensing mechanisms and parameters of typical insole systems based on different sensing techniques. Then this essay respectively discusses the three stages of gait parameters pre-processing, respectively: pressure reconstruction, feature extraction, and data normalization. Then, the relationship between gait features and pathogenic mechanisms is discussed, along with the introduction of insole systems that aid in medical research; Finally, the current challenges and future trends in the development of insole systems are discussed.
Topics: Aged; Humans; Medicine; Biomedical Research; Diabetic Foot; Gait; Muscles
PubMed: 37622919
DOI: 10.3390/bios13080833 -
Archives of Rheumatology Sep 2023The aim of this study was to evaluate possible peripheral and autonomic nerve involvement in familial Mediterranean fever (FMF) patients with nerve conduction studies,...
OBJECTIVES
The aim of this study was to evaluate possible peripheral and autonomic nerve involvement in familial Mediterranean fever (FMF) patients with nerve conduction studies, sympathetic skin response (SSR) and RR interval variability (RRIV).
PATIENTS AND METHODS
The comparative case series was conducted with 76 participants between November 2017 and December 2018. Forty-six FMF patients, [12 with amyloidosis (5 males, 7 females; mean age: 44.7±13.9 years) and 34 without amyloidosis (14 males, 20 females; mean age: 35.9±8.7 years)], and 30 healthy volunteers (11 males, 19 females; mean age: 38.4±10 years) were included in this study. Nerve conduction parameters, SSR latency and amplitude from palmar and plantar responses, and RRIV at rest and deep breathing were studied in all the subjects. Neuropathic symptoms of the patient group were evaluated using the survey of autonomic symptoms scale and the neuropathy disability score.
RESULTS
Nerve conduction studies of the patient group revealed polyneuropathy in seven (15.21%) patients and carpal tunnel syndrome in six (13.04%) patients. The mean amplitudes of SSR measured from the soles were significantly lower than the control group (p=0.041). The mean values of RRIV during rest and hyperventilation were lower in the patient group compared to the control group, but no statistically significant difference was found (p=0.484, p=0.341).
CONCLUSION
We detected that the prevalence of carpal tunnel syndrome in our patient population (13.04%) was higher than in the general population. Most of the changes in the range of parameters of SSR and RRIV determined in the patient group did not reach statistical significance, suggesting subclinical dysautonomia in FMF patients.
PubMed: 38046242
DOI: 10.46497/ArchRheumatol.2023.9695 -
American Journal of Veterinary Research Jun 2024The objective of this study was to optimize an MRI-based diffusion tensor imaging (DTI) protocol for imaging the plantar nerves at the level of the tarsus in normal...
OBJECTIVE
The objective of this study was to optimize an MRI-based diffusion tensor imaging (DTI) protocol for imaging the plantar nerves at the level of the tarsus in normal equine limbs.
SAMPLE
12 pelvic cadaver limbs from horses without evidence of proximal suspensory pathology were imaged with a 3T MRI system.
METHODS
For diffusion-weighted imaging, b values of 600, 800, and 1,000 s/mm2 were tested. Data were processed with DSI Studio. Cross-sectional areas of the medial and lateral plantar nerve along the plantar tarsus were recorded. The length and number of fiber tracts, signal-to-noise ratio, and DTI variables were recorded.
RESULTS
At the level of interest, the mean cross-sectional areas of the plantar nerves ranged from 5.03 to 7.42 mm2. The DTI maps consistently generated tracts in the region of the lateral and medial plantar nerves with DTI values in the range of values reported for peripheral nerves in humans. Our findings demonstrate that DTI of the medial and lateral plantar nerves can be performed successfully and used to generate quantitative parameters including fractional anisotropy and mean, axial, and radial diffusivity.
CLINICAL RELEVANCE
Quantitative data generated with this imaging technique can be used to noninvasively characterize the microstructural integrity of neural tissue with possible applications in the evaluation of pathologic changes to the plantar tarsal and metatarsal nerves of horses with proximal suspensory desmopathy.
PubMed: 38889743
DOI: 10.2460/ajvr.24.03.0092 -
Investigative and Clinical Urology Jul 2023To define transcutaneous medial plantar nerve stimulation (T-MPNS) as a new neuromodulation method and assess the efficacy of T-MPNS on quality of life (QoL) and... (Clinical Trial)
Clinical Trial
PURPOSE
To define transcutaneous medial plantar nerve stimulation (T-MPNS) as a new neuromodulation method and assess the efficacy of T-MPNS on quality of life (QoL) and clinical parameters associated with incontinence in women with idiopathic overactive bladder (OAB).
MATERIALS AND METHODS
Twenty-one women were included in this study. All women received T-MPNS. Two self-adhesive surface electrodes were positioned with the negative electrode near the metatarsal-phalangeal joint of the great toe on the medial aspect of the foot and the positive electrode 2 cm inferior-posterior of the medial malleolus (in front of the medio-malleolar-calcaneal axis). T-MPNS was performed 2 days a week, 30 minutes a day, for a total of 12 sessions for 6 weeks. Women were evaluated for incontinence severity (24-h pad test), 3-day voiding diary, symptom severity (Overactive Bladder Questionnaire [OAB-V8]), QoL (Quality of Life-Incontinence Impact Questionnaire [IIQ-7]), positive response and cure-improvement rates, and treatment satisfaction at baseline and at the 6th week.
RESULTS
Statistically significant improvement was found in the severity of incontinence, frequency of voiding, incontinence episodes, nocturia, number of pads, symptom severity, and QoL parameters at the 6th week compared with baseline. Treatment satisfaction, treatment success, and cure or improvement rates were found to be high at the 6th week.
CONCLUSIONS
T-MPNS was first described in the literature as a new neuromodulation method. We conclude that T-MPNS is effective on both clinical parameters and QoL associated with incontinence in women with idiopathic OAB. Randomized controlled multicenter studies are needed to validate the effectiveness of T-MPNS.
Topics: Female; Humans; Quality of Life; Tibial Nerve; Transcutaneous Electric Nerve Stimulation; Treatment Outcome; Urinary Bladder, Overactive; Urinary Incontinence
PubMed: 37417565
DOI: 10.4111/icu.20230009