Ultrasound imaging of the thenar motor branch of the median nerve: a cadaveric study

Improved visualization of median, ulnar nerves, and small branches in the wrist and palm using contrast-enhanced magnetic resonance neurography

Background

Magnetic resonance imaging of peripheral nerves in the wrist and palm is challenging due to the small size, tortuous course, complex surrounding tissues, and accompanying blood vessels. The occurrence of carpal palmar lesions leads to edema, swelling, and mass effect, which may further interfere with the display and identification of nerves.

Objective

To evaluate whether contrast-enhanced magnetic resonance neurography (ceMRN) improves the visualization of the morphology and pathology of the median, ulnar nerves, and their small branches in the wrist and palm.

Design

An observational study.

Methods

In total 57 subjects, including 36 volunteers and 21 patients with carpal palmar lesions, were enrolled and underwent ceMRN and non-contrast MRN (ncMRN) examination at 3.0 Tesla. The degree of vascular suppression, nerve visualization, diagnostic confidence, and lesion conspicuity was qualitatively assessed by two radiologists. Kappa statistics were obtained for inter-reader agreement. The signal-to-noise ratio, contrast ratio (CR), and contrast-to-noise ratio (CNR) of the median nerve were measured. The subjective ratings and quantitative measurements were compared between ncMRN and ceMRN.

Results

The inter-reader agreement was excellent (k > 0.8) for all qualitative assessments and visualization assessment of each nerve segment. Compared with ncMRN, ceMRN significantly improved vascular suppression in volunteers and patients (both p < 0.001). The ceMRN significantly enhanced nerve visualization of each segment (all p < 0.05) and diagnostic confidence in volunteers and patients (both p < 0.05). The ceMRN improved lesion conspicuity (p = 0.003) in patients. Quantitatively, ceMRN had significantly higher CRs of nerve versus subcutaneous fat, bone marrow, and vessels and CNR of nerve versus vessel than ncMRN (all p < 0.05).

Conclusion

The ceMRN significantly improves the visualization of peripheral nerves and pathology in the wrist and palm by robustly suppressing the signals of fat, bone marrow, and especially vessels in volunteers and patients.

Base of the Third Metacarpal as a Palpable and Reliable Landmark for Identifying the Median Nerve's Thenar Branch

PURPOSE

The objective of this study was to investigate whether the base of the third metacarpal can predict the location of the thenar branch (TB) of the median nerve and the accuracy of palpating the base of the third metacarpal.

METHODS

In 15 patients with ulnar nerve lesions around the elbow, we transferred the opponens motor branch to repair the deep terminal division of the ulnar nerve (DTDUN). Before surgery, we located the TB by palpating the base of the third metacarpal volarly. During surgery, we placed three needles at the following places: one at the entrance of the TB into the abductor pollicis brevis, another at the point where the TB contacted the thenar muscles, and third at the DTDUN's trajectory over the third metacarpal. We obtained fluoroscopic images and measured distances between the needles and structures with image software. We also examined the relationship between the TB, DTDUN, and the volar tubercle of the base of the third metacarpal in cadaver hands. Finally, we invited 22 surgeons to palpate the base of the third metacarpal on volunteer hands and verified their accuracy using fluoroscopy.

RESULTS

During surgery, after dissection and palpation of the TB, under fluoroscopy, we confirmed that the palpable bone prominence was the base of the third metacarpal. In cadaver dissections, we observed the TB crossing the volar tubercle of the base of the third metacarpal superficially from proximal to distal and from ulnar to radial. The DTDUN was, on average, 14 mm distal to the base of the third metacarpal distal limit. In total, 19 of the 22 surgeons correctly identified the base of the third metacarpal and consequently the trajectory of the TB.

CONCLUSIONS

The palpable base of the third metacarpal can be used to determine the trajectory of both the TB and DTDUN.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Understanding the Learning Curve of Carpal Tunnel Release With Ultrasound Guidance: A Review

Carpal tunnel syndrome (CTS) is the most common compressive neuropathy and can be treated through carpal tunnel release (CTR) if nonoperative treatments fail. CTR can be performed through a variety of techniques, including traditional open, mini-open, endoscopic, and CTR with ultrasound guidance (CTR-US). The evidence on endoscopic CTR is mixed, due to a higher potential for nerve injury with endoscopic CTR compared to traditional open CTR. CTR-US offers the potential advantage of allowing the visualization of all key anatomical structures, combined with a very small incision and minimal soft tissue insult. As with any ultrasonographic technique or procedure, the learning curve needs to be considered for any provider considering adopting CTR-US. However, literature on ultrasound use around the wrist, including early evidence on the learning curve of CTR-US specifically, demonstrates this skill can be learned relatively quickly by providers with a wide range of prior experience in ultrasound and CTR. Overall, there is a need for high-quality studies comparing different CTR techniques, particularly CTR-US, as it offers the potential for considerable cost savings.

Nerve Imaging in the Wrist

Neuropathic symptoms involving the wrist are a common clinical presentation that can be due to a variety of causes. Imaging plays a key role in differentiating distal nerve lesions in the wrist from more proximal nerve abnormalities such as a cervical radiculopathy or brachial plexopathy. Imaging complements electrodiagnostic testing by helping define the specific lesion site and by providing anatomical information to guide surgical planning. This article reviews nerve anatomy, normal and abnormal findings on ultrasonography and magnetic resonance imaging, and common and uncommon causes of neuropathy.

Bifid median nerve as an anatomical risk factor for carpal tunnel syndrome: A meta-analysis

As the median nerve enters the carpal tunnel, it is a single nerve that soon bifurcates into lateral and medial branches into the hand. If the bifurcation is proximal to the carpel tunnel, a bifid median nerve results. Carpal tunnel syndrome is often associated with a bifid median nerve with or without a persistent median artery. Individual keywords and MeSH phrases were searched in the Google Scholar, SCOPUS, and PubMed databases. Full texts were then collected and assessed for suitability. The prevalence of bifid median nerve at the wrist joint in normal and carpal tunnel syndrome wrists (pre-canal part) and the mean difference between groups were recorded. Only human data were used to test the findings. The pooled odds ratio (with minimal heterogeneity) was 1.50 [1.17-1.93, 95% CI]. The bifid median nerve cross-sectional area (CSA) was significantly greater than that of a solitary median nerve in normal wrists. The mean difference in CSA between the two was 1.50 mm² [0.56-2.45 mm² , 95% CI] without heterogeneity (i²  = 0). Sex and laterality distributions scarcely differed between the two types of wrists. Owing to the insufficiency of data, the relationships with mean height and weight were not examined. There was a 50% greater incidence of bifid median nerves in carpal tunnel syndrome patients than in normal subjects. A bifid median nerve increases the mean CSA at the wrist joint by 1.5 mm² . These findings indicate that the bifid median nerve is an anatomical risk factor for carpal tunnel syndrome. This article is protected by copyright. All rights reserved.

Atlas of Sonographic Anatomy of the Hand and Wrist

Accurate knowledge of the technique of ultrasonographic (US) examination and of normal US appearance is a prerequisite for a successful US examination of the wrist and hand. In this article, we describe our standard US examination as well as the normal US findings of the hand and wrist.

Sonographic Diagnosis of Carpal Tunnel Syndrome

Diagnostic ultrasound in the diagnosis of carpal tunnel syndrome is firmly established. Preoperative evaluation is based on quantitative parameters such as measurement of the pathologically enlarged cross-sectional area of the nerve. The value of postoperative ultrasound lies in the visualization of the anatomy and the conclusions that can be drawn from it. It focuses on the semiquantitative sonographic parameters of nerve compression. Nerve lesions and persistent strictures can be visualized and clearly localized. In recurrent disease, the primary focus is to dynamically exclude postoperative scarring, which results in a reduction of nerve gliding.

Thumb Injuries and Instabilities. Part 2: Spectrum of Lesions

The motor function of the thumb and its alignment with regard to the hand make it particularly vulnerable to trauma. Pathology encountered in this joint is varied, and imaging techniques play a crucial role in the diagnosis and characterization of injury. Despite advances in imaging technology, acute thumb injuries remain a challenge for radiologists. Currently, standard radiography and ultrasonography are frequently used first-line imaging techniques. Computed tomography is most often indicated for complex fractures and dislocations. Magnetic resonance imaging may be used to optimally characterize soft tissues and bone marrow. In this article, we cover the most common traumatic injuries: fractures, dislocations, collateral ligament injuries of the metacarpophalangeal joint, as well as soft tissue lesions.

Thumb Injuries and Instabilities. Part 1: Anatomy, Kinesiology, and Imaging Techniques of the Thumb

The unique anatomical characteristics of the thumb offer a broad range of motion and the ability to oppose thumb and finger, an essential function for grasping. The motor function of the thumb and its orientation make it particularly vulnerable to trauma. Pathologic lesions encountered in this joint are varied, and imaging techniques play a crucial role in injury detection and characterization. Despite advances in diagnostic accuracy, acute thumb injuries pose a challenge for the radiologist. The complex and delicate anatomy requires meticulous and technically flawless image acquisition. Standard radiography and ultrasonography are currently the most frequently used imaging techniques. Computed tomography is most often indicated for complex fractures and dislocations, and magnetic resonance imaging may be useful in equivocal cases. In this article, we present the relevant anatomy and imaging techniques of the thumb.

"Million dollar nerve" magnetic resonance neurography: first normal and pathological findings

OBJECTIVES

To evaluate prospectively the feasibility of magnetic resonance neurography (MRN) in identifying the anatomical characteristics of thenar muscular branch (TMB) of the median nerve, also known as the "million dollar nerve," in patients and controls.

METHODS

Thirteen patients affected by carpal tunnel syndrome (CTS) and four healthy controls had their hands scanned on a 3-T MR imaging scanner for TMB visualization. Median nerve anatomical variations were classified into four groups according to Poisel's classification system modified by Lanz. TMB signal intensity and diameter were assessed for the diagnosis of neuropathy.

RESULTS

TMB was successfully identified in all patients and subjects by using MRN. The most suitable pulse sequences to identify and measure nerve diameter were 3D DW-PSIF and T2-FS-TSE. The axial oblique and sagittal oblique planes are complementary in demonstrating its entire course. TMB had mostly an extraligamentous course with radial side origin (93.8%, each). All patients experienced increased T2 signal intensity (p < 0.001) and thickened nerves. Mean TMB diameters were 1.27 ± 0.21 mm (range, 1.02-1.74 mm) and 0.87 ± 0.16 mm (0.73-1.08 mm) (p = 0.008) in the patient and control groups, respectively.

CONCLUSION

MRN is a reliable imaging technique for identification and anatomical characterization of TMB in patients affected by CTS. This innovative imaging workup may therefore be included in the preoperative evaluation of patients scheduled for carpal tunnel release, especially in CTS with TMB involvement or even in isolated TMB neuropathy.

KEY POINTS

• Magnetic resonance neurography allows precise visualization of the thenar muscular branch of the median nerve. • Thenar muscular branch anatomical variations can be correctly identified. • Preoperative scanning can contribute to reducing the risk of iatrogenic injuries during carpal tunnel release, especially in carpal tunnel syndrome with thenar muscular branch involvement or even in isolated thenar muscular branch neuropathy.

Five Wrist Operations That Give the Best Results

LEARNING OBJECTIVES

After reading this article and viewing the videos, the participant should be able to: 1. Recognize the following five wrist operations as consistent options for different wrist injuries: carpal tunnel release, medial femoral condyle bone flap for scaphoid nonunion associated with carpal collapse and avascular necrosis, scaphocapitate arthrodesis for Kienböck disease, percutaneous screw fixation of nondisplaced scaphoid fracture, and four-corner arthrodesis. 2. Know the state-of-the-art of these five procedures. 3. State the indications of each operation. 4. List the surgical steps of these five procedures.

SUMMARY

The wrist is a complex joint that concentrates different types of tissues (e.g., bone, cartilage, ligaments, nerves, vessels) and a broad different spectrum of diseases. Treatment of wrist injuries has improved during recent years, mainly because of improvement in strategy, techniques, microsurgical equipment, understanding anatomy and improvements in technology. In this article, we present the five operations (i.e., carpal tunnel release, medial femoral condyle bone flap for scaphoid nonunion associated with carpal collapse and avascular necrosis, scaphocapitate arthrodesis for Kienböck disease, percutaneous screw fixation of nondisplaced scaphoid fracture, and four-corner arthrodesis) that have consistently given good outcomes in patients suffering from different wrist injuries/maladies.

Microinvasive Carpal Tunnel Release Using a Retractable Needle-Mounted Blade

We report 166 microinvasive ultrasound-guided carpal tunnel releases using the MICROi-Blade (Summit Medical Products, Inc, Sandy, UT), a needle-based tool for cutting under ultrasound guidance. The 6-month follow-up of the first 21 cases, including 5 bilateral releases, showed a progressive reduction in median pain scores, Boston Carpal Tunnel Questionnaire (BCTQ) Symptom Severity Scale scores, and BCTQ Functional Status Scale scores. The median return to work was 7 days. The 3-month follow-up of 62 subsequent cases showed similar improvement in the BCTQ scores and return to work. There were no complications. This report supports the effectiveness of the technique.

Supraretinacular endoscopic carpal tunnel release: A safe alternative method for treatment of carpal tunnel syndrome

PURPOSE

Supraretinacular endoscopic carpal tunnel release (SRECTR) is a technique in which an endoscope is inserted superficial to the flexor retinaculum through a subcutaneous tunnel. The benefits of this method include a clear view for the surgeon and absence of median nerve compression. Surgeons can operate with a familiar view of the flexor retinaculum and median nerve downward, similar to open surgery. This study aimed to investigate the learning curve for SRECTR, an alternate method for carpal tunnel release, and evaluate its complications and the functional outcomes using a disposable commercial kit.

METHODS

We examined the open conversion rates and complications associated with SRECTR in 200 consecutive patients performed by two surgeons. We compared the operative time operated by a single surgeon. We evaluated outcomes in 191 patients according to Kelly's grading system. Patients' mean follow-up period was 12.7 months.

RESULTS

Nine patients required conversion to open surgery. There were no injuries to the nerves and tendons and no hematoma or incomplete dissection of the flexor retinaculum. The operative times varied between 11 and 34 minutes. We obtained the following results based on Kelly's grading of outcomes: excellent in 116, good in 59, fair in 13, and poor in 3 patients.

CONCLUSIONS

We found no patients with neurapraxia, major nerve injury, flexor tendon injury, superficial palmar arch injury, and hematoma. Although there was a learning curve associated with SRECTR, we performed 200 consecutive cases without neurovascular complications. This method may be a safe alternative to minimally invasive carpal tunnel surgery.

High-resolution ultrasound of the marginal mandibular branch of the facial nerve: Normal appearance and pathological findings in a postsurgical case series

BACKGROUND

The aim of this study was to validate high-resolution ultrasound (US) as an imaging modality able to map the normal marginal mandibular nerve (MMN) and recognize its abnormalities in the postoperative setting.

METHODS

The ability of US to recognize the MMN was first tested by injecting latex under US guidance on three fresh frozen cadavers. Then, a standardized scanning protocol was established on 20 healthy volunteers based on appropriate landmarks. Finally, a postsurgical series of three patients with MMN abnormalities were examined with US.

RESULTS

In the cadaveric study, US-guided latex injection provided identification of the MMN. In healthy volunteers, US was able to recognize the MMN for a segment of 3.4 ± 1.2 cm in length. Pathologic abnormalities of the MMN were detected and characterized in three patients.

CONCLUSIONS

High-resolution US is a valuable diagnostic tool to identify the MMN and might have potential for detecting its pathologic changes.

Carpal tunnel syndrome caused by the entrapment of a bifid Lanz IIIA Type anatomical variant of median nerve: A case report and systematic literature review

Background:

Carpal tunnel syndrome (CTS) is the most common entrapment peripheral neuropathy. Median nerve may present several anatomical variations such as a high division or bifid median nerve (BMN). A thorough knowledge of the normal anatomy and variations of the median nerve at the wrist are fundamental to reduce complications during carpal tunnel release.

Case Description:

A 63-year-old man with CTS underwent preoperative ultrasound that showed the entrapment of the median nerve and disclosed a BMN Lanz IIIA Type anatomical variation at the carpal tunnel. During the surgery, the anatomical variant of a BMN at the wrist has been visualized. Both nervous rami entirely occupied the carpal canal and this may have predisposed to the development of the entrapment syndrome. Nor persistent median artery, or other associated abnormalities, have been identified. At the 6 months follow-up control, the patient referred a good surgical recovery with complete resolution of the preoperative symptoms of the median nerve entrapment.

Conclusion:

A rare case of Lanz IIIA BMN Type at the wrist has been encountered in a patient with a CTS and a systematic review and practical considerations have been presented with the aim of raising awareness to the neurosurgical community of a such rare variant that could be encountered during carpal tunnel release procedures. CTS may be caused by the entrapment of a BMN Lanz IIIA Type anatomical variant of median nerve. Preoperative US would help to identify such patients to reduce risk of iatrogenic injuries.

A Preligamentous Variant of the Thenar Motor Branch of the Median Nerve

We report a rare variant of the thenar motor branch (TMB) of the median nerve. A preligamentous TMB was discovered during revision carpal tunnel release in a 49-year-old man. The prevalence and characteristics of TMB variations are discussed. The literature describing iatrogenic injury to the TMB variants, surgical treatment, and preoperative screening tools is reviewed. Recognition of anatomic variants of the TMB is essential considering notable consequences of iatrogenic injury.

The superficial anatomical landmarks are not reliable for predicting the recurrent branch of the median nerve

PURPOSE

The variability of the recurrent branch (RB) of the median nerve lends itself to an increased risk of injury when performing the minimally invasive approach for carpal tunnel release without its direct visualization. This risk is less so when it is released via the more invasive open approach as the RB can be easily identified, but the drawback is that of longer postoperative patient recovery time. Therefore, performing these releases via the less invasive approach should be more favorable for patients providing it could be done safely. Hence with there being a positive link between the hypertrophy of the thenar musculature and the course of RB according to previous studies.

METHODS

We dissected 28 hands of 14 donated bodies fixed using Thiel's method to try to demonstrate these findings of the associations among the RB, palmar creases and other superficial anatomical landmarks. Fisher's exact test was conducted to verify the relationship between those structures statistically.

RESULTS

Statistically significant links were found between the type of the RB and the type of the palmar creases (p value = 0.0094) and between the RB type and the palmaris longus muscle presence (p value = 0.028).

CONCLUSION

It was inferred that palmar creases and other superficial anatomical landmarks listed in the text could not be used to predict the variability of the RB and the choice of mini-invasive approach should not be based on their course.

Ultrasound-guided percutaneous release of the carpal tunnel: comparison of the learning curves of a senior versus a junior operator. A cadaveric study

OBJECTIVE

The purpose was to evaluate, in a cadaveric cohort, the feasibility and the learning curve of ultrasound-guided percutaneous carpal tunnel release.

MATERIALS AND METHODS

Fourteen carpal tunnel releases were carried out on unembalmed cadavers by a senior and a junior radiologist. Procedures were realized with an 18-MHz linear probe. An anatomical evaluation was first performed using ultrasound to detect any anatomical variant. After hydrodissection of the carpal tunnel with lidocaine, a 3-mm hook knife was introduced into the security zone to perform a retrograde section of the transverse carpal ligament (TCL) under ultrasound guidance. Anatomical dissection was performed for each wrist. The main evaluation criterion was the complete TCL section. The procedure duration (minutes), skin incision size (millimeters), the integrity of the median nerve, thenar motor branch, and palmar vascular arch were also evaluated.

RESULTS

The senior operator was able to perform a complete release after training on three specimens and the junior operator after four specimens (p > 0.05). In most of the cases when complete release was not achieved, it was due to an incomplete section of the distal TCL (10 mm missing section on average). Mean duration time of procedure was 14 min (11 min for the senior versus 17 min for the junior, p > 0.05). Damage of neither the median nerve nor the vascular structure was observed. Mean size of the skin incision was 3 mm.

CONCLUSION

The ultrasound-guided percutaneous release of the carpal tunnel is demonstrated to be a procedure with a rapid learning curve.

Ultrasound Imaging of Disorders of Small Nerves of the Extremities: Less Recognized Locations

Ultrasound is a well-proven imaging modality for showing peripheral nerve disorders and guiding perineural injections. The aim of this review is to focus on small peripheral nerve abnormalities, which are usually not recognized by sonologists. In fact, most of these small nerves have a tiny diameter (<2 mm), and their anatomy is less familiar. We describe the most common causes of small peripheral nerve disorders, providing an accurate description of their anatomic locations and relationships with adjacent structures; we also focus on technical hints that may help in their evaluation.

Carpal tunnel ultrasound: is the "safe zone" on the ulnar side of the median nerve really avascular?

INTRODUCTION

Numerous publications have studied the regional anatomy of the carpal tunnel to define a "safe zone" to reduce the risk of perioperative neurovascular complications. This zone, located between the ulnar neurovascular bundle and the median nerve, is considered to be safe mainly because of the absence of vascular structures. This study aims to assess the presence of arterioles within this area using superb microvascular imaging (SMI).

MATERIALS AND METHODS

The images from patients who underwent a bilateral routine wrist ultrasound with SMI, between January 28 and February 28, 2019, were retrospectively reviewed by two radiologists to evaluate the presence and location of arterioles in the safe zone. In addition, cadaveric wrists injected with intra-arterial red latex underwent dissection of the carpal tunnel.

RESULTS

The images from 27 patients (54 wrists) were reviewed. In the safe zone, arterioles were seen superficial to the retinaculum in 36 wrists (36/54; 66.7%) and deep to the retinaculum in 21 wrists (21/54; 38.9%). The arterioles located deep to the retinaculum were more frequently found close to the median nerve (21/54; 38.9%) than to the ulnar artery (9/54; 16.7%). In five cadaveric wrists, arterioles were detected superficial to the retinaculum in 3 wrists (3/5; 60%) and deep to the retinaculum in 2 wrists (2/5; 40%).

CONCLUSION

Arterioles can be seen in the safe zone both superficial and deep to the flexor retinaculum. Deep to the retinaculum, they are mainly observed in the proximal aspect of the carpal tunnel and more frequently close to the median nerve.

KEY POINTS

• Superb microvascular imaging (SMI) enables the visualization of arterioles within the "safe zone" of the carpal tunnel (visible both superficial and deep to the flexor retinaculum). • Arterioles were more frequently observed in the proximal aspect of the carpal tunnel. • Deep to the retinaculum, arterioles were more frequently seen in proximity to the median nerve.

Partial anterior tunnel syndrome: a retrospective analysis of ultrasound findings in four surgically proven cases

We present the cases of four patients (two men and two women, mean age of 48.5 years) with surgically confirmed partial anterior tarsal syndrome, diagnosed by ultrasound. All patients reported pain in the dorsal aspect of the forefoot radiating to the first intermetatarsal space. Ultrasound showed compression of the medial branch of the deep fibular nerve by the extensor hallucis brevis tendon at the level of the Lisfranc joint, associated with a hypoechoic neuroma. The ultrasound allowed a correct diagnosis to be obtained, which was not evident from clinical examination or by standard radiographs (four patients) or MRI (three patients). Surgery confirmed the sonographic findings, and all patients showed complete recovery.

Ultrasound-guided percutaneous compartment release: a novel technique, proof of concept, and clinical relevance

OBJECTIVE

Ultrasound-guided thread release (USGTR) is a minimally invasive technique with excellent clinical outcomes currently used in clinical practice to divide the transverse carpal ligament in carpal tunnel syndrome. The purpose of this study is to determine whether this technique can be modified for use in large anatomical compartments in soft embalmed cadaveric models.

MATERIALS AND METHODS

Two operators adapted the USGTR technique for use in muscular compartments of the forearms and legs in a single soft embalmed cadaver. An iterative approach was used to adapt and improve the technique for use in large compartments, using equipment readily available in most radiology departments.

RESULTS

The USGTR technique was successfully modified and both operators were able to accurately divide fascial layers over distances of up to 30 cm using the modified technique. Fascial division was confirmed with ultrasound and dissection.

CONCLUSIONS

This adapted technique can successfully be used to divide fascial planes over longer distances than is currently achieved in clinical practice. The improved outcomes associated with USGTR at the carpal tunnel may therefore also be achievable in fasciotomy procedures in larger anatomical compartments. Further study is required to investigate the effects of this modified USGTR technique on intracompartmental pressure.

Ultrasound-Guided Surgery for Carpal Tunnel Syndrome: A New Interventional Procedure

Carpal tunnel syndrome (CTS) may be treated surgically if medical treatment fails. The classical approach involves release of the flexor retinaculum by endoscopic or open surgery. Meta-analyses have shown that the risk of nerve injury may be higher with endoscopic treatment. The recent contribution of ultrasound to the diagnosis and therapeutic management of CTS opens new perspectives. Ultrasound-guided carpal tunnel release via a minimally invasive approach enables the whole operation to be performed as a percutaneous radiological procedure. The advantages are a smaller incision compared with classical techniques; great safety during the procedure by visualization of anatomic structures, particularly variations in the median nerve; and realization of the procedure under local anesthesia. These advantages lead to a reduction in postsurgical sequelae and more rapid resumption of daily activities and work. Dressings are removed by the third day postsurgery. Recent studies seem to confirm the medical, economic, and aesthetic benefits of this new approach.