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World Neurosurgery Jul 2020Carpal tunnel syndrome represents compression of the median nerve in the carpal tunnel, which is defined by the carpal bones on the lateral, medial, and dorsal aspects...
Carpal tunnel syndrome represents compression of the median nerve in the carpal tunnel, which is defined by the carpal bones on the lateral, medial, and dorsal aspects and the transverse carpal ligament on the anterior aspect. Symptoms of carpal tunnel syndrome include paresthesia, anesthesia, paresis, and pain located in the median nerve distribution. In severe cases, there may be atrophy of median nerve-innervated thenar muscles. In the United States, carpal tunnel syndrome affects approximately 3.72% of the population. Conservative measures, such as bracing, steroid injections, and physical and occupational therapy, are commonly employed. However, many patients still require more definitive surgical management, which may be in the form of open or endoscopic procedures. Regardless of surgical approach, the clinical success rates of carpal tunnel release have been reported to be 75%-90%. Recurrence rates are 8.4%-15% over 4-5 years, with the lower end of this range representing the Agee single-portal technique. Endoscopic carpal tunnel release leads to reduced postoperative pain and an increase in transient neurologic deficits; however, no improvements have been reported in overall complication rate, subjective satisfaction, return to work, postoperative grip and pinch strength, and operative time. In this technical video, we present a case of single-incision endoscopic carpal tunnel release in a patient with severe symptoms after conservative measures failed. The patient experienced a noncomplicated postoperative course and demonstrated an excellent recovery at follow-up visits. Surgical decompression is an important treatment for refractory carpal tunnel syndrome, and videos such as this provide guidance for safe and effective treatment (Video 1).
Topics: Carpal Tunnel Syndrome; Electromyography; Endoscopy; Female; Humans; Median Nerve; Middle Aged; Video-Assisted Surgery
PubMed: 32348893
DOI: 10.1016/j.wneu.2020.04.123 -
Occupational Medicine (Oxford, England) Jul 2017Ultrasound is an established method of viewing the median nerve in the carpal tunnel syndrome (CTS). There is some evidence to suggest that immediate changes may occur... (Review)
Review
BACKGROUND
Ultrasound is an established method of viewing the median nerve in the carpal tunnel syndrome (CTS). There is some evidence to suggest that immediate changes may occur in the median nerve before and after hand activity. The evidence for the validity and reliability of ultrasound for testing acute changes in the median nerve has not been systematically reviewed to date.
AIMS
To evaluate the evidence for visible change in ultrasound appearance of the median nerve after hand activity.
METHODS
A literature search was designed, and three reviewers independently selected published research for inclusion. Two reviewers independently appraised papers using the Evidence Based Library and Information Practice (EBLIP) appraisal checklist, while the third reviewer resolved discrepancies between appraisals.
RESULTS
Ten studies were appraised and the results showed an increase in median nerve cross-sectional area following activity, with a return to normal size within 1 h following activity. Both healthy individuals and those diagnosed with CTS participated, all were small convenience samples. Ultrasonographic measurements of the median nerve were reliable in the four studies reporting this, and the studies demonstrated high quality.
CONCLUSIONS
Good-quality evidence as identified by the EBLIP appraisal checklist suggests that following hand activity, the median nerve changes in size in the carpal tunnel. The results may not be generalizable to all people and activities due to the use of small convenience sampling and narrow range of activities studied, in all of the studies appraised.
Topics: Carpal Tunnel Syndrome; Female; Hand; Humans; Male; Median Nerve; Movement; Ultrasonography
PubMed: 28582584
DOI: 10.1093/occmed/kqx059 -
Muscle & Nerve Jun 2016The most frequently described anomalous neural connections between the median and ulnar nerves in the upper limb are: Martin-Gruber anastomosis (MGA), Marinacci... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
The most frequently described anomalous neural connections between the median and ulnar nerves in the upper limb are: Martin-Gruber anastomosis (MGA), Marinacci anastomosis (MA), Riche-Cannieu anastomosis (RCA), and Berrettini anastomosis (BA). The reported prevalence rates and characteristics of these anastomoses vary significantly between studies.
METHODS
A search of electronic databases was performed to identify all eligible articles. Anatomical data regarding the anastomoses were pooled into a meta-analysis using MetaXL 2.0.
RESULTS
A total of 58 (n = 10,562 upper limbs) articles were included in the meta-analysis. The pooled prevalences were: MGA, 19.5% (95% confidence interval [CI], 16.2%-23.1%); MA, 0.7% (95% CI, 0.1%-1.7%); RCA, 55.5% (95% CI, 30.6%-79.1%); and BA, 60.9% (95% CI, 36.9%-82.6%). The results also showed that MGA was more commonly found unilaterally (66.8%), on the right side (15.7%), following an oblique course (84.8%), and originating from the anterior interosseous nerve with a prevalence of 57.6%.
CONCLUSIONS
As anastomoses between the median and ulnar nerves occur commonly, detailed anatomical knowledge is essential for accurate interpretation of electrophysiological findings and reducing the risk of iatrogenic injuries during surgical procedures. Muscle Nerve 54: 36-47, 2016.
Topics: Databases, Factual; Humans; Median Nerve; Nervous System Malformations; Neural Conduction; Ulnar Nerve; Upper Extremity
PubMed: 26599506
DOI: 10.1002/mus.24993 -
Ortopedia, Traumatologia, Rehabilitacja Oct 2020Nerve compression underlying carpal tunnel syndrome (CTS) results in an increase in the threshold of superficial sensation in the area supplied by the median nerve,...
BACKGROUND
Nerve compression underlying carpal tunnel syndrome (CTS) results in an increase in the threshold of superficial sensation in the area supplied by the median nerve, which is a mixed nerve dominated by sensory fibres. The distribution of sensory symptoms is strongly dependent on the degree of electrophysiological dysfunction of the median nerve. The association between carpal tunnel syndrome and ulnar nerve entrapment at wrist level is still unclear. Patho-logical processes leading to median neuropathy in CTS may affect ulnar nerve motor and sensory fibers in the Guyon canal. This may explain the extra-median spread of sensory symptoms in CTS patients.
MATERIAL AND METHODS
The study involved 88 patients (104 hands), with 70 women (83 hands) and 18 men (21 hands) aged between 25 and 77 years. 50 age- and sex-matched subjects without carpal tunnel syndrome were used as a control group. The diagnosis of carpal tunnel syndrome was made according to the criteria of the American Academy of Neurology 1993 guidelines. Based on the results of an ENG trace evaluating the degree of conduction disturbances in the median nerve, the patients were classified to one of three severity subgroups. The threshold of sensory excitability to pulsed current was determined in a test with single 100 ms rectangular pulses.
CONCLUSIONS
1. The threshold of sensation in the fingers innervated by the median and ulnar nerve is significantly lon-ger in patients with CTS than in controls. 2. Surgical treatment decreases the threshold of sensation in the fingers innervated by the median nerve. 3. Surgical treatment does not decrease the threshold of sensation in the fingers innervated by the ul-nar nerve. 4. The preoperative and postoperative threshold of sensation in the fingers innervated by the median and ulnar nerve is significantly longer in patients with severe carpal tunnel than in mild and moderate cases.
Topics: Adult; Aged; Carpal Tunnel Syndrome; Female; Humans; Male; Median Nerve; Middle Aged; Neuralgia; Poland; Sensory Thresholds; Ulnar Nerve
PubMed: 33568572
DOI: 10.5604/01.3001.0014.4214 -
Journal of Biomechanical Engineering Mar 2023The spacing between the median nerve and transverse carpal ligament (TCL) within the carpal tunnel can potentially affect the nerve morphology. This study aimed to...
The spacing between the median nerve and transverse carpal ligament (TCL) within the carpal tunnel can potentially affect the nerve morphology. This study aimed to quantify the spatial relationship between the median nerve and transverse carpal ligament in asymptomatic hands. Twelve subjects were recruited to image the carpal tunnel using robot-assisted ultrasound. The median nerve and TCL were segmented from each image and three-dimensionally reconstructed using kinematic information from the robot. The TCL-median nerve distance, nerve cross-sectional area, circularity, and position were measured along the entirety of the nerve length within the carpal tunnel. Results were averaged at every 5% of nerve length. At the nerve length percentages of 0% (distal), 25%, 50%, 75%, and 100% (proximal), the TCL-median nerve distance (±SD) was 0.7 ± 0.4, 0.7 ± 0.2, 0.5 ± 0.2, 0.5 ± 0.2, and 0.6 ± 0.3 mm, respectively. The corresponding nerve cross-sectional area was 9.4 ± 1.9, 10.6 ± 2.6, 11.2 ± 2.1, 11.2 ± 1.7, and 9.7 ± 1.9 mm2. A one-way analysis of variance showed no significant differences between the respective percentages of nerve length for TCL-median nerve distance (p = 0.219) and cross-sectional area (p = 0.869). Significant (p < 0.0001) but weak correlations were observed between the TCL-median nerve distance with cross-sectional area (r = -0.247) and circularity (r = -0.244). This study shows that the healthy median nerve morphology is consistent along the continuous nerve length within the carpal tunnel, supporting the use of 2D imaging in the evaluation of the healthy nerve.
Topics: Humans; Median Nerve; Carpal Tunnel Syndrome; Ligaments, Articular; Wrist Joint; Hand
PubMed: 36416297
DOI: 10.1115/1.4056290 -
Seminars in Musculoskeletal Radiology Apr 2022Neuropathies of the elbow represent a spectrum of disorders that involve more frequently the ulnar, radial, and median nerves. Reported multiple pathogenic factors...
Neuropathies of the elbow represent a spectrum of disorders that involve more frequently the ulnar, radial, and median nerves. Reported multiple pathogenic factors include mechanical compression, trauma, inflammatory conditions, infections, as well as tumor-like and neoplastic processes. A thorough understanding of the anatomy of these peripheral nerves is crucial because clinical symptoms and imaging findings depend on which components of the affected nerve are involved. Correlating clinical history with the imaging manifestations of these disorders requires familiarity across all diagnostic modalities. This understanding allows for a targeted imaging work-up that can lead to a prompt and accurate diagnosis.
Topics: Diagnostic Imaging; Elbow Joint; Humans; Median Nerve; Nerve Compression Syndromes; Peripheral Nerves; Elbow Injuries
PubMed: 35609574
DOI: 10.1055/s-0042-1743407 -
Clinics in Sports Medicine Jul 2020Sports-related peripheral neuropathies account for 6% of all peripheral neuropathies and most commonly involve the upper extremity. The routes of the median, radial, and... (Review)
Review
Sports-related peripheral neuropathies account for 6% of all peripheral neuropathies and most commonly involve the upper extremity. The routes of the median, radial, and ulnar nerves are positioned in arrangements of pulleys and sheaths to glide smoothly around the elbow. However, this anatomic relationship exposes each nerve to risk of compression. The underlying mechanisms of the athletic nerve injury are compression, ischemia, traction, and friction. Chronic athletic nerve compression may cause damage with moderate or low pressure for long or intermittent periods of time.
Topics: Athletic Injuries; Elbow; Humans; Median Nerve; Peripheral Nervous System Diseases; Radial Nerve; Ulnar Nerve; Elbow Injuries
PubMed: 32446578
DOI: 10.1016/j.csm.2020.02.006 -
Hand (New York, N.Y.) Jan 2023Our purpose was to describe structural and morphological features of the median nerve and carpal tunnel on magnetic resonance imaging (MRI) studies obtained before,...
BACKGROUND
Our purpose was to describe structural and morphological features of the median nerve and carpal tunnel on magnetic resonance imaging (MRI) studies obtained before, immediately after, 6 weeks after, and 6 years after endoscopic carpal tunnel release (ECTR).
METHODS
In this prospective cohort study, 9 patients with a diagnosis of carpal tunnel syndrome (CTS) underwent ECTR. Standardized MRI studies were obtained before ECTR, immediately after ECTR, and 6 weeks and 6 years after surgery. Structural and morphological features of the median nerve and carpal tunnel were measured and assessed for each study with comparisons made between each time point.
RESULTS
All 9 patients had complete symptom resolution postoperatively. On the immediate postoperative MRI, there was a discrete gap in the transverse carpal ligament in all patients. There was retinacular regrowth noted at 6 weeks in all cases. The median nerve cross-sectional area and the anterior-posterior dimension of the carpal tunnel at the level of the hamate increased immediately after surgery and these changes were maintained at 6 years.
CONCLUSIONS
We defined structural and morphological changes on MRI for the median nerve and carpal tunnel in patients with continued symptom resolution 6 years after ECTR. Changes in median nerve and carpal tunnel morphology that occur immediately after surgery remain unchanged at mid-term follow-up in asymptomatic patients. Established imaging criteria for CTS may not apply to postoperative patients. Magnetic resonance imaging appears to be of limited clinical utility in the workup of persistent or recurrent CTS.
Topics: Humans; Median Nerve; Carpal Tunnel Syndrome; Follow-Up Studies; Prospective Studies; Ligaments
PubMed: 34933606
DOI: 10.1177/15589447211058819 -
Pain Practice : the Official Journal of... Jul 2023Complex regional pain syndrome (CRPS) can be distinguished as type I without and type II with electrophysiological evidence of major nerve lesion. The pathophysiology of...
OBJECTIVE
Complex regional pain syndrome (CRPS) can be distinguished as type I without and type II with electrophysiological evidence of major nerve lesion. The pathophysiology of both subgroups is still under investigation. The aim of this research is to demonstrate the nerve morphology and electrophysiology in CRPS type I patients.
MATERIALS AND METHODS
Bilateral median and ulnar nerve cross-sectional areas were evaluated with ultrasound and also median and ulnar nerve conduction studies of both hands were performed. Cross-sectional areas of median and ulnar nerves and nerve conduction studies in healthy controls were also obtained and compared with the patients.
RESULTS
Twenty-five male patients and 11 healthy male controls were enrolled in the study. The mean age of the patients was 24.08 ± 5.50 years and controls was 23.18 ± 5.09 (p > 0.05). Compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes of the diseased side were found significantly lower than the healthy side (p < 0.05). Both median and ulnar nerve distal motor latency values were significantly higher in the patient group (p < 0.05). There was no significant difference in the median and ulnar nerve cross-sectional area when compared with the opposite extremity and healthy volunteers.
CONCLUSION
The lower SNAP and CMAP amplitudes of the median and ulnar nerves compared to the healthy side and the prolongation of the affected side median and ulnar nerve distal motor latencies of the affected individuals may indicate axonal involvement in patients with CRPS type 1. Decreased CMAP amplitudes may also indicate muscle atrophy due to a decrease in the number of functional motor units.
Topics: Humans; Male; Adolescent; Young Adult; Adult; Ulnar Nerve; Neural Conduction; Reflex Sympathetic Dystrophy; Upper Extremity; Axons; Median Nerve
PubMed: 36915259
DOI: 10.1111/papr.13222 -
Median nerve and carpal arch morphology changes in women with type 2 diabetes: a case-control study.Journal of Ultrasound Sep 2022The aim of this study is to investigate the changes in median nerve and transverse carpal ligament (TCL)-formed carpal arch morphology as possible risk factors for...
BACKGROUND
The aim of this study is to investigate the changes in median nerve and transverse carpal ligament (TCL)-formed carpal arch morphology as possible risk factors for median nerve entrapment in women with type 2 diabetes.
METHODS
The distal carpal tunnel was imaged using ultrasound in 30 female subjects (15 with type 2 diabetes, 15 controls). The morphological parameters of the median nerve and carpal arch were derived from the ultrasound images. One-way analysis of variance (ANOVA) was used for statistical analysis.
RESULTS
Diabetic women had an enlarged median nerve area (p < 0.05), salong with a maller carpal arch size, as indicated by a reduced palmar bowing index of the TCL (p < 0.05), and arch area (p < 0.05) than controls. The distance from the median nerve centroid to the volar boundary of the TCL was reduced in diabetic women (p < 0.05) compared to the controls.
CONCLUSIONS
Women with type 2 diabetes have reduced available space for the median nerve within the carpal arch due to the enlarged nerve and reduced arch size, making the median nerve more susceptible to entrapment within the tunnel. The current study shows that presence of diabetes increases the risk of median nerve entrapment in women and requires early detection of symptoms to avoid carpal tunnel syndrome.
Topics: Carpal Bones; Carpal Tunnel Syndrome; Case-Control Studies; Diabetes Mellitus, Type 2; Female; Humans; Median Nerve
PubMed: 34472043
DOI: 10.1007/s40477-021-00606-7