Sonographic visualization of the first branch of the lateral plantar nerve (baxter nerve): technique and validation using perineural injections in a cadaveric model

Optimizing injection accuracy for Baxter's nerve entrapment: an ultrasonography-guided approach based on anatomical surface landmarks

INTRODUCTION

The clinical feasibility and applicability of surface landmarks for Baxter nerve entrapment to proximal and distal sites is unclear. This study provides anatomical guidelines for optimal transducer placement using two specific landmarks, the most inferior tip of the medial malleolus (A) and the most protruding posterior tip of the calcaneus (B), to enhance the diagnostic and therapeutic injection efficacy for proximal and distal entrapment sites.

MATERIALS AND METHODS

Eighty-six feet from 45 fresh cadavers (25 male and 20 female) were dissected to determine Baxter's nerve (BN) localization. With A and B as key landmarks, distances (OB, OBN, BBN, and BNx) were measured to accurately localize the nerve. The OB distance was divided into four equal-length quadrants or zones. Twenty feet from 10 fresh cadavers (5 males and 5 females) underwent ultrasonography-guided injection using in-plane and out-of-plane techniques. Two practitioners marked the landmarks to ensure reproducibility and an experienced anesthesiologist administered the injections. The spread of the injected dye was assessed, and statistical analyses were conducted.

RESULTS

Average OB, OBN, BBN, and BNx distances were 50.55 ± 5.83 mm, 7.19 ± 5.85 mm, 43.77 ± 5.31 mm, and 12.13 ± 5.75 mm, respectively. Significant sex-related differences (O to B; B to BN) and notable disparities between the distances on the right and left sides (O to BN; BN to X-axis) were observed. Most of the BN (81.4%) was located in zone 1, representing 25% of the OB length. For entrapment site 1, the in-plane technique achieved a 100% success rate whereas the out-of-plane method achieved an 80% success rate. For entrapment site 2, the out-of-plane approach (90% success) outperformed the in-plane approach (20% success).

CONCLUSION

Using two specific landmarks provides reliable guidelines for optimal transducer placement during injections targeting compressive neuropathy at proximal and distal entrapment sites.

Baxter's nerve: the hidden culprit of chronic heel pain

Baxter's nerve entrapment, an underrecognized cause of medial plantar heel pain, is frequently misdiagnosed as plantar fasciitis, leading to inadequate treatment. This condition involves compression of the first branch of the lateral plantar nerve, often resulting in chronic, burning pain with neurological symptoms. Despite accounting for up to 20% of chronic heel pain cases, clinical awareness remains low, delaying diagnosis and management. Differential diagnosis from plantar fasciitis, tarsal tunnel syndrome, and calcaneal stress fractures is crucial. High-resolution ultrasound, electromyography, and targeted clinical evaluation improve diagnostic accuracy. Management includes conservative interventions such as physical therapy, orthotics, and neuromodulation, with interventional options like corticosteroid injections and surgical decompression reserved for refractory cases. Increasing clinician awareness and integrating advanced imaging into routine practice are essential for improving patient outcomes.

Image-Guided Foot and Ankle Injections

Ultrasound is a high-resolution, real-time imaging modality that is frequently used for image-guided procedures. Due to the highly complex anatomy of the foot and ankle, ultrasound should be considered a first-line imaging modality for injections and procedures in this region.

How to perform Baxter's nerve blockage easily by ultrasound in chronic heel pain: Four simple steps

Baxter's neuropathy is one of the overlooked causes of chronic heel pain. Diagnosing neuropathy in Baxter's can be challenging due to its potential occurrence as a secondary condition to other common syndromes that cause heel pain, such as plantar fasciitis, calcaneal spur, hypertrophic muscle, tenosynovitis, space-occupying lesions or trauma. Ultrasound is a reliable and easily accessible device that guides injections for the treatment of Baxter's neuropathy. We have written this letter as a guide, especially for beginner and professional pain specialists.

The role of high-resolution ultrasound and MRI in the evaluation of peripheral nerves in the lower extremity

Lower extremity peripheral neuropathy is a commonly encountered neurologic disorder, which can lead to chronic pain, functional disability, and decreased quality of life for a patient. As diagnostic imaging modalities have improved, imaging has started to play an integral role in the detection and characterization of peripheral nerve abnormalities by non-invasively and accurately identifying abnormal nerves as well as potential causes of neuropathy, which ultimately leads to precise and timely treatment. Ultrasound, which has high spatial resolution and can quickly and comfortably characterize peripheral nerves in real time along with associated denervation muscle atrophy, and magnetic resonance neurography, which provides excellent contrast resolution between nerves and other tissues and between pathologic and normal segments of peripheral nerves, in addition to assessing reversible and irreversible muscle denervation changes, are the two mainstay imaging modalities used in peripheral nerve assessment. These two modalities are complimentary, and one may be more useful than the other depending on the nerve and location of pathology. Imaging must be interpreted in the context of available clinical information and other diagnostic studies, such as electrodiagnostic tests. Here, we offer a comprehensive overview of the role of high-resolution ultrasound and magnetic resonance neurography in the evaluation of the peripheral nerves of the lower extremity and their associated neuropathies.

Sonographic assessment of the tarsal tunnel compared to cadaveric findings: a pictorial study

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.

Image-Guided Foot and Ankle Injections

Ultrasound is a high-resolution, real-time imaging modality that is frequently used for image-guided procedures. Due to the highly complex anatomy of the foot and ankle, ultrasound should be considered a first-line imaging modality for injections and procedures in this region.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part VII, nerves of the lower limb

OBJECTIVES

To perform a Delphi-based consensus on published evidence on image-guided interventional procedures for peripheral nerves of the lower limb (excluding Morton's neuroma) and provide clinical indications.

METHODS

We report the results of a Delphi-based consensus of 53 experts from the European Society of Musculoskeletal Radiology who reviewed the published literature for evidence on image-guided interventional procedures offered around peripheral nerves in the lower limb (excluding Morton's neuroma) to derive their clinical indications. Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus was considered strong when > 95% of experts agreed with the statement or broad when > 80% but < 95% agreed. The results of the Delphi-based consensus were used to write the paper.

RESULTS

Nine statements on image-guided interventional procedures for peripheral nerves of the lower limb have been drafted. All of them received strong consensus. Image-guided pudendal nerve block is safe, effective, and well tolerated with few complications. US-guided perisciatic injection of anesthetic provides good symptom relief in patients with piriformis syndrome; however, the addition of corticosteroids to local anesthetics still has an unclear role. US-guided lateral femoral cutaneous nerve block can be used to provide effective post-operative regional analgesia.

CONCLUSION

Despite the promising results reported by published papers on image-guided interventional procedures for peripheral nerves of the lower limb, there is still a lack of evidence on the efficacy of most procedures.

KEY POINTS

• Image-guided pudendal nerve block is safe, effective, and well tolerated with few complications. • US-guided perisciatic injection of anesthetic provides good symptom relief in patients with piriformis syndrome; however, the addition of corticosteroids to local anesthetics still has an unclear role. • US-guided lateral femoral cutaneous nerve block can be used to provide effective post-operative regional analgesia. The volume of local anesthetic affects the size of the blocked sensory area.

Neurologic Disorders Affecting the Foot and Ankle

The neurologic causes of foot and leg dysfunction are reviewed. Disorders causing foot and ankle pain, weakness, or other sensorimotor disturbances often cause difficulty with ambulation and prompt patients to seek medical evaluation. Physical signs and symptoms along with targeted diagnostic testing are needed to come to the correct diagnosis and treatment plan. An overview of peripheral nerve, muscle, and central nervous system disorders affecting the foot and leg are discussed.

Ultrasound block of first branch of the lateral plantar nerve (baxter nerve): case report of a promising and effective treatment for heel chronic pain

Chronic heel pain is a challenging diagnosis and although it is a common and disabling condition frequently mistreated. Baxter Nerve (BN) entrapment is responsible for 20% of heel pain and can be managed by an ultrasound guide nerve block, a simple, safe, and durable technique. A 67-year-old woman complained of paraesthesia on the left heel and a “stepping on glass” feeling. Various techniques were performed to manage her symptoms without any results. An ultrasound BN block was finally performed with an instant relief and satisfactory pain control for the follow-up period of six months. This clinical report highlights the success of the ultrasound BN block as an effective and lasting solution for chronic heel pain.

Novel, user-friendly landmarks for localizing Baxter's nerve: A cadaveric 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.

Anatomical study and branching point of neurovascular structures at the medial side of the ankle

Nerve entrapment and blood circulation impairment associated with the medial side of the ankle are not uncommon. The purpose of this study was to describe the anatomical basis of neurovascular structures of the medial ankle which comprised the number, origin, branching pattern, and branching point. Forty feet of fresh cadavers were examined by using 2 reference lines: the malleolar-calcaneal (MC) and navicular-calcaneal (NC) axes. We recorded number, origin, length of the 2 axes, the locations and widths of neurovascular structures on MC and NC axes, the branching point of neurovascular structures, and the branching pattern of neurovascular structures was recorded and was separated into 5 types. The posterior tibial nerve (PTN) bifurcated to plantar and calcaneal nerves and branched proximally to the tarsal tunnel (TT). The posterior tibial artery bifurcated to plantar and calcaneal arteries and branched inferiorly to PTN and within the TT. The calcaneal nerves and arteries had more variation of number and origin. The most common branching point of calcaneal nerves and arteries is within the TT, except the medial calcaneal nerve. It branched proximally to the TT. The anatomical knowledge from this study is important for the diagnosis and treatment of clinicians.

Ultrasound-Guided Hydrodissection for Baxter's Neuropathy Secondary to Plantar Fasciitis: A Case Report

Plantar heel pain is a common pain condition encountered in clinical practice. The common etiologies include plantar fasciitis, calcaneal spur, calcaneus stress fracture, systemic causes, and trauma. Neurogenic causes, including entrapment at the tarsal tunnel or Baxter's nerve entrapment, can contribute to the heel pain and should not be overlooked. In this case report, we describe a patient with severe heel pain, presenting with overlapping features of plantar fasciitis and neuropathic pain. Magnetic resonance imaging suggested Baxter's nerve entrapment, and a subsequent ultrasound-guided hydrodissection of Baxter's nerve provided long-lasting pain relief.

ACR Appropriateness Criteria® Chronic Foot Pain

Chronic foot pain is a frequent clinical complaint, which can significantly impact the quality of live in some individuals. These guidelines define best practices with regards to requisition of imaging studies based on specific clinical scenarios, which have been grouped into different variants. Each variant is accompanied by a brief description of the usefulness, advantages, and limitations of different imaging modalities. The present narrative is the result of an exhaustive assessment of the available literature and a thorough review process by a panel of experts on Musculoskeletal Imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Advanced Ankle and Foot Sonoanatomy: Imaging Beyond the Basics

Ankle/foot pain is a common complaint encountered in clinical practice. Currently, due to the complex anatomy, the diagnosis and management of the underlying musculoskeletal disorders are extremely challenging. Nowadays, high-resolution ultrasound has emerged as the first-line tool to evaluate musculoskeletal disorders. There have been several existing protocols describing the fundamental sonoanatomy of ankle/foot joints. However, there are certain anatomic structures (e.g., Lisfranc ligament complex or Baxter nerve) which are also clinically important. As they are rarely elaborated in the available literature, a comprehensive review is necessary. In this regard, the present article aims to brief the regional anatomy, illustrate the scanning techniques, and emphasize the clinical relevance of the ankle/foot region.

Ultrasound-guided posterior antebrachial cutaneous nerve block utilising the 'fat-filled flat tunnel': Description of technique and cutaneous sensory block area

The aim of the study was to investigate an ultrasound-guided posterior antebrachial cutaneous nerve block based on visualising the nerve within the fat-filled flat tunnel and describe the area of cutaneous sensory loss. A total of 12 healthy volunteers were included in the study. The posterior antebrachial cutaneous nerve was identified within the fat-filled flat tunnel in the upper arm using high-frequency ultrasound. The nerve was blocked using an in-plane needle guidance technique with 1 ml 2% lidocaine. Sensory loss to pinprick was evaluated 15 minutes after performing the block and the cutaneous sensory block area mapped. Ultrasound visualisation of the posterior antebrachial cutaneous nerve in the fat-filled flat tunnel was possible in all volunteers. The median distance of the posterior antebrachial cutaneous nerve to the lateral epicondyle of the elbow was 67.5 (range 54–105) mm. Loss of sharpness sensation to pinprick extended from the posterior aspect of the distal upper arm and posterior forearm to the wrist. The median cutaneous sensory block area was 103 (range 61–341) cm2. Two volunteers had a sensory block over the anterior forearm of 29 and 10 cm2 respectively. This amounted to 11% and 4.5% of the total cutaneous sensory block area. One volunteer had a sensory block over the dorsum of the hand of 39 cm2 (15% of the total cutaneous sensory block area). The results of this study indicate that the fat-filled flat tunnel can be a useful sono-anatomical landmark in identifying the posterior antebrachial cutaneous nerve and may serve as a target for injection. Although sensory block is predominantly confined to the posterior distal arm and forearm, inter-individual variability in the area and distribution was observed. Sensory block in the anterior forearm and dorsum of the hand can occur. The study was prospectively registered at the Australian New Zealand Clinical Trials Registry, identifier ACTRN12618000891224.

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.

Ultrasound-Guided Release of the Tibial Nerve and Its Distal Branches: A Cadaveric Study

OBJECTIVES

The purpose of the study was to determine whether ultrasound (US)-guided surgery is a viable type of surgery for performing an effective release/decompression of the constricting structures that are responsible for focal nerve compression in tarsal tunnel syndrome.

METHODS

Ultrasound guidance was used on cadaveric specimens to delineate the anatomic course of the nerves and vessels in the medial ankle that comprise the structures involved in tarsal tunnel syndrome. Ultrasound guidance was used on cadaveric specimens and assisted in delineating a safe surgical zone to adequately and effectively release these constrictive structures of the proximal and distal tarsal tunnels. The US-guided tarsal tunnel release/decompression was performed through 2 small 1- to 2-mm portals. After US-guided release, anatomic dissection was used to check the efficacy (release of the flexor retinaculum and deep abductor hallucis muscle) and safety (absence of neurovascular or tendon injury) of the procedure.

RESULTS

In 12 fresh cadaveric specimens, US-guided release of the tibial nerve (proximal tarsal tunnel) and its branches (distal tarsal tunnel) at the medial ankle was effective in all 12 specimens (100% release rate), without any signs of compromise or injury into the neurovascular structures.

CONCLUSIONS

Ultrasound-guided tarsal tunnel release is a feasible surgical procedure that can be safe and effective with the proper training, although further investigation is warranted. This type of surgery may promote faster recovery with less postoperative morbidity, including pain, but this will be the subject of a further investigation.

Interfascicular septum of the calcaneal tunnel and its relationship with the plantar nerves: A cadaveric study

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.

Clinical-anatomic mapping of the tarsal tunnel with regard to Baxter's neuropathy in recalcitrant heel pain syndrome: part I

Purpose

Neuropathy of the Baxter nerve (BN) seems to be the first cause of the heel pain syndrome (HPS) of neurological origin.

Methods

41 alcohol–glycerol embalmed feet were dissected. We documented the pattern of the branches of the tibial nerve (TN) and describe all relevant osteofibrous structures. Measurements for the TN branches were related to the Dellon–McKinnon malleolar-calcaneal line also called DM line (DML) for the proximal TT and the Heimkes Triangle for the distal TT. Additionally, we performed an ultrasound-guided injection procedure of the BN and provide an algorithm for clinical usage.

Results

The division of the TN was 16.4 mm proximal to the DML. The BN branches off 20 mm above the DML center or 30 mm distally to it. In most of the cases, the medial calcaneal branch (MCB) originated from the TN proximal to the bifurcation. Possible entrapment spots for the medial and lateral plantar nerve (MPN, LPN), the BN and the MCB are found within a circle of 5 mm radius with a probability of 80%, 83%, and 84%, respectively. In ten out of ten feet, the US-guided injection was precisely allocated around the BN.

Conclusions

Our detailed mapping of the TN branches and their osteofibrous tubes at the TT might be of importance for foot and ankle surgeons during minimally invasive procedures in HPS such as ultrasound-guided ankle and foot decompression surgery (UGAFDS).

Anatomic Delineation of Tarsal Tunnel Innervation via Ultrasonography

OBJECTIVES

High-resolution ultrasonography (US) can play an important role in studying nerves, as it has several advantages. Entrapments of distal tibial nerve branches can be mapped out or diagnosed with selective anesthetic blocks, and US can guide therapeutic procedures, such as radiofrequency ablation and selective infiltrations of specific nerve branches. The aim of this study was to verify that US is an effective method for accurately locating the posterior tibial nerve and its terminal branches, such as the medial calcaneal branch, the first calcaneal branch, and the medial and lateral plantar nerves.

METHODS

In this study, we analyzed the correlation between US mapping and real anatomy after cadaveric dissection, assessing the distribution and variability of the tibial nerve and its terminal branches. We used 12 fresh anatomic specimens of the foot and ankle, including the calf. A high-resolution US study of the tibial nerve and its branches was performed.

RESULTS

The results of the US studies of the anatomic specimens were drawn as paper diagrams and in data collection tables. Both were completed twice per anatomic specimen, first using the results of the US study and second using the results from dissection of the anatomic specimens; this approach enabled us to compare the results and verify whether the US study and the dissection correlated on the topography of the tibial nerve and its terminal branches. We found almost total agreement between the US and dissection results, with no significant differences between the evaluations.

CONCLUSIONS

On the basis of this work, we can conclude that high-resolution US is almost 100% effective as a tool for identifying the tibial nerve and its branches, enabling the specialist to make diagnoses or perform selective treatments on each nerve branch and even to design surgical interventions by observing the patient's anatomy before performing the dissection.

Sonographic Visualization of the Posterior Cutaneous Nerve of the Forearm: Technique and Validation Using Perineural Injections in a Cadaveric Model

OBJECTIVES

To determine the ability to sonographically identify the posterior cutaneous nerve of the forearm (PCNF) and its distal epicondylar branches using sonographically guided perineural injections in an unembalmed cadaveric model.

METHODS

A single experienced operator used a 12-3-MHz linear array transducer to identify the PCNF and its distal epicondylar region branches in 10 unembalmed cadaveric specimens (6 right and 4 left) obtained from 10 donors. Sonographically guided perineural PCNF injections were then completed with a 22-gauge, 38-mm stainless steel needle to deliver 0.25 mL of 50% diluted colored latex at 3 points along the PCNF. The latex location was then confirmed via dissection.

RESULTS

The 10 donors included 4 male and 6 female cadavers aged 48 to 94 years (mean, 73 years) with body mass indices of 19 to 37 kg/m² (mean, 26 kg/m² ). The operator sonographically identified the PCNF and several distal branches traversing over or directly adjacent to the lateral epicondyle in all 10 specimens. Only 7 of 10 specimens showed a distinct PCNF bifurcation into anterior and posterior divisions, and all 7 were accurately identified and localized on sonography. There was no evidence of latex overflow to clinically relevant adjacent structures or injury to regional vessels or nerves.

CONCLUSIONS

High-resolution sonography can identify the PCNF and its distal epicondylar branches. Sonographic evaluation of the PCNF should be included in the evaluation of patients presenting with refractory or atypical lateral elbow pain syndromes. Diagnostic and therapeutic sonographically guided procedures targeting the PCNF or its lateral epicondylar branches are feasible and warrant further investigation.

Ultrasound-Guided Radiofrequency Denervation of the Medial Calcaneal Nerve

OBJECTIVE

Plantar fasciosis is a common complaint of athletes, particularly for runners. The medial calcaneal nerve (MCN) may play a role in the pain syndrome, and radiofrequency (RF) denervation has been previously reported. The hypothesis is that ultrasound-guided denervation of the MCN results in symptomatic improvement.

DESIGN

Retrospective cohort.

SETTING

Private practice.

PATIENTS

Twenty-nine patients previously receiving ultrasound-guided RF denervation of the MCN, having failed conservative therapy, were assessed in 2 groups, those more than (group 1, n = 16) or less than (group 2, n = 13) 6 months since the procedure.

INTERVENTIONS

Ultrasound-guided RF denervation of the MCN.

MAIN OUTCOME MEASURES

Pain scores before denervation, as well as at maximal pain relief and the time of the interview. Levels of satisfaction and attitudes toward surgery were also assessed.

RESULTS

Pain scores decreased significantly in both groups, for both best and residual pain scores. Group 1 mean pain scores were 8.56 before procedure, 2.81 (P < 0.001 compared to baseline) at best pain score, and 3.75 (P < 0.01) residual pain score. Group 2 mean pain scores were 7.23 before procedure, 3.77 (P < 0.01) at best pain score and 4.92 (P < 0.01) residual pain score. Levels of satisfaction were predominantly positive (69% of group 1% and 54% of group 2 were either somewhat or very satisfied), with attitudes toward surgery unchanged.

CONCLUSIONS

For patients with refractory plantar heel pain, ultrasound-guided denervation of the MCN can potentially improve symptoms, although efficacy needs assessing in comparative studies.

CLINICAL RELEVANCE

Ultrasound-guided denervation of the MCN provides a further management option for patients with refractory plantar fasciosis.

US of the Peripheral Nerves of the Lower Extremity: A Landmark Approach

Ultrasonography (US) is commonly used to assess the peripheral nerves of the lower extremity because of its many advantages over magnetic resonance (MR) imaging. The most obvious advantages over MR imaging are superior soft-tissue resolution, low cost, portability, lack of magnetic susceptibility artifact, and the ability to image patients who cannot undergo MR imaging. US has been shown to have equal specificity and greater sensitivity than MR imaging in the evaluation of peripheral nerves. Additional benefits are the capability of real-time and dynamic imaging, and the ability to scan an entire extremity quickly without the need for a patient to lie motionless for long periods of time, as with MR imaging. Any abnormal findings can be easily compared against the contralateral side. Published literature has shown that US has clinical utility in patients suspected of having peripheral nerve disease: US can be used to guide diagnostic and therapeutic decisions, as well as help confirm electrodiagnostic findings. Common indications for lower extremity peripheral nerve US are the evaluation for injury due to penetrating trauma, entrapment by scar tissue, or tumor. To confidently perform US of the peripheral nerves of the lower extremity, it is important to gain a thorough knowledge of anatomic landmarks and the course of each nerve. Readers who may not be familiar with US will be introduced to the basics of scanning the peripheral nerves of the lower extremity. Important anatomic landmarks and common sites of injury and entrapment will be reviewed.

Sonographic evaluation of hindfoot disorders

Foot pain is a common orthopedic condition that can have an impact on health-related quality of life. The evaluation of plantar hindfoot pain begins with history and physical examination. Imaging modalities, standard radiographs, sonography, MR, CT are often utilized to clarify the diagnosis. The article is a detailed description of the sonographic evaluation of the plantar fascia and its disorders as well as the common etiologies in the differential diagnosis of plantar fasciopathy.