The effectiveness of nerve mechanical interface treatment for entrapment neuropathies in the limbs: A systematic review with metanalysis

BACKGROUND

Neurodynamic approach employs neural mobilization and mechanical nerve interface techniques. While published studies investigated the efficacy of neural mobilization, it is currently unknown whether manual treatment of the nerve mechanical interface is effective in the treatment of people with entrapment neuropathies.

OBJECTIVES

Assess the effectiveness of mechanical interface treatment, including joint and soft tissue techniques, on pain and function in people with peripheral entrapment neuropathies.

DESIGN

Intervention systematic review with metanalysis.

METHODS

the databases MEDLINE, CINAHL, AMED, APA PsycINFO, SPORTDiscus, PubMed and ScienceDirect were searched from their inception to October 2022. Randomized controlled trials investigating mechanical interface treatment in isolation in patients with peripheral entrapment neuropathies were included. Two independent reviewers performed study selection, data extraction and risk of bias assessment using the Cochrane RoB 2.0 tool. Certainty of evidence for each outcome was judged using the GRADE framework.

RESULTS

11 studies were included in the review, all investigating carpal tunnel syndrome (CTS). Due to high heterogeneity of interventions and comparators, only five studies were pooled in a random-effects meta-analysis. There was evidence of mechanical interface techniques being more effective in reducing pain than sham (MD -2.47 [-3.94;-0.99]) and similarly effective as neural mobilization (MD -0.22 [-0.76; 0.33]) in CTS, albeit with low to very low certainty in the results.

CONCLUSION

mechanical interface techniques are effective for improving pain and function in people with CTS. However, the marked heterogeneity of included interventions and comparators prevents clinical recommendation of specific treatments.

Steroid efficacy in Meralgia Paresthetica: A systematic review and meta-analysis

Objective

To determine the efficacy of steroid injections for pain relief in patients with meralgia paresthetica (MP).

Methods

All the literature published until March 2023 was explored from several databases, including EBSCO, PubMed, EMBASE, Cochrane Library, Google Scholar, and Scopus. Articles investigating the change in pain status of MP patients after steroid injection were included. The primary outcomes were complete pain relief, pain scores at 15 days and one month after intervention. When compared to the baseline, the secondary outcomes for the steroid group included pain scores at the end of treatment and quality of life, which were further evaluated by two factors, namely mental and physical health.

Results

The analysis of the studies validated that steroids were significantly successful in providing complete pain relief (p-value = 0.00001), and in reducing the pain score of patients with meralgia paresthetica at 15 days (p-value = 0.02), but not at one month (p-value = 0.79) as compared to the control group. The analysis did not reveal any significant subgroup differences among various steroids (P = 0.52; CI: 0.01 - 0.10; RR: 0.04; I2 = 0%). Mental health (MD = 4.23; 95% CI = 0.42 to 8.03; p = 0.03, I2 = 0%) was significantly improved in the steroid group when compared with baseline.

Conclusion

Steroids injections can play an important role in improving symptoms and complications of meralgia paresthetica, especially in the short term.

Causes of Iatrogenic Median Nerve Injury after Endoscopic Carpal Tunnel Release

Background: Endoscopic carpal tunnel release (ECTR) is a less invasive procedure but has a higher risk of complications. We analysed ECTR cases dividing them into three periods according to a single surgeon's experience when the ECTR was performed: the initial, midterm and late period. Cases of iatrogenically induced median nerve injuries that occurred after ECTR were then noted and evaluated. Methods: We reviewed 195 ECTRs done with the 2-portal technique and divided the patients into three groups according to periods of when ECTR was done. The indications for ECTR surgery were limited to severe CTS cases. These groups of patients were similar in terms of age, duration of disease, electrophysiological study results and severity of the disease. The patients were evaluated for median neuropathy pre- and postoperatively using Semmes-Weinstein monofilament test (SWT), Disabilities of the arm, shoulder and hand (DASH) Score, Coin-flip test (CFT), postoperative paraesthesias and complications, such as pillar pain, and so on. Electrophysiological evaluation was performed only preoperatively. Results: Postoperative median nerve recovery was overall good. Normal recovery was noted in 181 cases (93%). SWT, DASH and CFT were all significantly improved upon follow-up in all three groups. In terms of iatrogenic neuropathy, median nerve palsy worsened (including those transiently worsened) after ECTR in 11 cases (5.6%), even in the later period. The sensory disturbance was equally worsening from the radial to the ulnar side. Conclusions: The fact that there were neurologically worsened cases even in the later period, when the operator is higher skilled in the technique, suggests that the surgical technique itself may be the one posing higher risk than the level of surgical skill. The most likely causes of aggravated nerve palsy were a direct injury by cannula insertion at the proximal portal, or additional median nerve compression during cannula insertion into the carpal tunnel. Level of Evidence: Level IV (Therapeutic).

The consequences of a thoracic outlet syndrome's entrapment model on the biomechanics of the ulnar nerve - Cadaveric study

STUDY DESIGN

A cross sectional cadaveric measurement study.

INTRODUCTION

The etiology of entrapment neuropathies, such as carpal tunnel syndromes or thoracic outlet syndromes (TOS), is usually not only linked with the compressive lesion of the nerve but can also be associated with fibrosis and traction neuropathy.

PURPOSE OF THE STUDY

This work studies the biomechanics of the ulnar nerve in a cadaveric model of thoracic outlet syndrome (TOS). We explored the biomechanical impact of a restriction of mobility of the ulnar nerve. We measured if it could significantly affect the deformation undergone by the nerve on the rest of its path.

METHODS

We studied 14 ulnar nerves from 7 embalmed cadavers. We opened three 6.5cm windows (at the wrist, forearm, and arm), and two optical markers 2cm apart were sutured to the ulnar nerve. We then studied the deformation of the ulnar nerve in three successive tensioning positions inspired by the ULNT3 manoeuvre (Upper Limb Neural Test 3). We then fixed the brachial plexus to the clavicle to mimic a nerve adhesion at the thoracic outlet.

RESULTS

Fixing the brachial plexus to the clavicle bone had significant effects on ulnar nerve mobility. In the position of intermediate tension, the nerve deformation increased by +0.68% / +1.43% compared to the control measure. In the position of maximum tension, it increased by +1.16% / +1.94%, pushing the nerve beyond the traumatic threshold of 8% of deformation causing reversible damage to axonal transport and vascularization.

CONCLUSIONS

Our nerve adhesion at the thoracic outlet showed significant effects on the mobility of the ulnar nerve compared to the control situation, by significantly increasing the deformation undergone throughout the rest of the nerve's course, and by taking it over the 8% of physiological traumatic deformation.

Accessory Hand Muscles Over the Transverse Carpal Ligament: An Obstacle in Carpal Tunnel Surgery

BACKGROUND

Carpal tunnel syndrome (CTS) is an entrapment neuropathy caused by compression of the median nerve throughout the carpal tunnel. It is the most common entrapment neuropathy, with an estimated prevalence of 4%-7%. Surgical management is more effective in moderate to severe and severe CTS. CTS recurs in approximately 20% of patients, and up to 12% of these patients require reoperation. Knowledge of normal anatomy and variations would improve the success rate of the index surgery. Atypical causes of CTS were reported, including ganglion cysts, synovial hypertrophy, lipomas, bone fracture, bone fragments, tumor of soft tissues or bones, neurofibromas, neuromas, vascular malformations, and accessory muscles. Accessory muscles are commonly detected in upper limbs. However, their concomitant presentation with CTS has rarely been reported. We aimed to present different accessory muscles diagnosed during CTS surgery through a systematic review of the literature with our exemplary case.

METHODS

A systematic review/meta-analysis was performed concomitant with a case presentation.

RESULTS

Accessory muscles associated with CTS were as follows: palmaris longus, 28.6%; lumbrical muscles, 19.3%; palmaris profundus, 17.8%; flexor digitorum superficialis, 16.1%; transverse carpal muscle, 5%; flexor digitorum indicis, 4.2%; flexor superficialis indicis, 4.2%; flexor sublimis, 0.8%; accessory superficialis longus, 0.8%; flexor pollicis longus, 0.8%; abductor digiti minimi, 0.8%; abductor digiti quinti, 0.8%; and flexor digitorum superficialis brevis, 0.8%. Accessory muscles were mostly noticed during CTS surgery (88.2%).

CONCLUSIONS

Knowledge of possible variations within the carpal tunnel would improve the surgeon's capability during CTS surgery.

An update on imaging of tarsal tunnel syndrome

Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the tibial nerve (TN) within the tarsal tunnel (TT) at the level of the tibio-talar and/or talo-calcaneal joints. Making a diagnosis of TTS can be challenging, especially when symptoms overlap with other conditions and electrophysiological studies lack specificity. Imaging, in particular MRI, can help identify causative factors in individuals with suspected TTS and help aid surgical management. In this article, we review the anatomy of the TT, the diagnosis of TTS, aetiological factors implicated in TTS and imaging findings, with an emphasis on MRI.

Diabetic Mononeuropathies and Diabetic Amyotrophy

This brief review describes the etiology, pathophysiology, clinical features, therapy and prognosis of the diabetic mononeuropathies and diabetic amyotrophy and neuropathic cachexia. Mononeuropathies include cranial neuropathies, of which the oculomotor nerve is most commonly affected, and are thought to be due to microvascular occlusion. Peripherally, entrapment neuropathies occur in both the upper and lower limbs and are due to compression of an already damaged nerve in anatomically restricted channels. Diabetic radiculopathies occur in the dermatones of the thorax and abdomen, mimicking intraabdominal or intrathoracic pathology. I also describe the features of the rare but very distinctive diabetic amyotrophy and neuropathic cachexia. Overall, the prognosis from these conditions is excellent with residual pain or muscle weakness being rare with the exception of diabetic amyotrophy where the prognosis is dependent upon cooperation with intensive rehabilitation. Therapies include "watchful waiting," physical therapy and rarely surgical intervention, which may be urgently needed for nerve decompression and reversal of motor defects.

Comparison of the modified method and the median sensory-ulnar motor latency difference in the diagnosis of carpal tunnel syndrome

OBJECTIVES

This study aimed to compare the modified method and the median sensory-ulnar motor latency difference in the diagnosis of carpal tunnel syndrome.

METHODS

The study recruited the electromyography results of 105 hands of 60 patients who had a complaint of carpal tunnel syndrome (CTS) on the hand diagram. The average sensory-ulnar motor delay difference (MSUMLD) was determined by simple subtraction, and the modified method was calculated based on the results of the classic method. The modified method and the MSUMLD were compared according to their sensitivity and specificity in the diagnosis of CTS.

RESULTS

In this study, 54 hands were evaluated with a unilateral nerve conduction study (45 right; 9 left). A total of 23 hands with CTS and 31 hands without CTS were diagnosed electrophysiologically. The MSUMLD had 91.3% sensitivity and 93.5% specificity; however, the modified method showed 95.7% sensitivity and 96.8% specificity in the diagnosis of CTS. Moreover, the modified method had 100% sensitivity and specificity in the diagnosis of moderate CTS.

CONCLUSIONS

The modified method may have higher diagnostic accuracy than the MSUMLD for diagnosing CTS.

Ultrasonography for the diagnosis of carpal tunnel syndrome: an umbrella review

BACKGROUND

Numerous sonographic modalities and parameters have been used to diagnose carpal tunnel syndrome (CTS), with varying accuracy. Our umbrella review aimed to summarize the evidence from systematic reviews and meta-analyses regarding the use of ultrasound imaging to diagnose CTS.

METHODS

Systematic reviews and meta-analyses meeting the inclusion criteria were searched in PubMed, Embase, Medline, Web of Science, and Cochrane databases from inception to March 2022. Critical appraisal, data extraction, and synthesis were performed in accordance with the criteria for conducting an umbrella review.

RESULTS

Sixteen reviews were included. Three reviews were classified as high quality, one as moderate, four as low, and eight as critically low. The cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet demonstrated the best reliability and diagnostic accuracy among multiple parameters. A cutoff CSA value of 9-10.5 mm² gave the highest diagnostic performance in the general population. The degree of CSA enlargement was correlated with CTS severity. Sonoelastography and Doppler ultrasound might provide additional insights into CTS evaluation as median nerve stiffness and vascularity at the wrist were increased in these patients.

CONCLUSIONS

Sonography is a reliable tool to diagnose CTS, with inlet CSA being the most robust parameter. Sonoelastography and Doppler ultrasound can serve as auxiliary tools to confirm CTS diagnoses. Further studies are needed to expand the use of sonography for diagnosing CTS, especially in the presence of concomitant neuromuscular disease(s).

Peripheral neurological complications during COVID-19: A single center experience

Background and aims

We highlight the peripheral neurologic complications of coronavirus disease 2019 (COVID-19) associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an ongoing global health emergency.

Methods

We evaluated twenty-five patients admitted to the COVID-19 Recovery Unit (CRU) at New York-Presbyterian Weill Cornell University Medical Center after intensive care hospitalization with confirmed severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), whom neurology was consulted for weakness and/or paresthesias. All patients were clinically evaluated by a neuromuscular neurologist who performed electrodiagnostic (EDX) studies when indicated. Magnetic resonance imaging (MRI) of the affected regions, along with nerve and muscle biopsies were obtained in select patients to better elucidate the underlying diagnosis.

Results

We found fourteen out of twenty-five patients with prolonged hospitalization for COVID-19 infection to have peripheral neurological complications, identified as plexopathies, peripheral neuropathies and entrapment neuropathies. The other eleven patients were not found to have peripheral neurologic causes for their symptoms. Patients with peripheral neurological complications often exhibited more than one type of concurrently. Specifically, there were four cases of plexopathies, nine cases of entrapment neuropathies, and six cases of peripheral neuropathies, which included cranial neuropathy, sciatic neuropathy, and multiple mononeuropathies.

Conclusions

We explore the possibility that the idiopathic peripheral neurologic complications could be manifestations of the COVID-19 disease spectrum, possibly resulting from micro-thrombotic induced nerve ischemia.

A safe and easy-to-use ultrasound-guided hydrodissection technique for the carpal tunnel syndrome: a minimally invasive approach

Carpal tunnel syndrome (CTS), compression of the median nerve lying deep under the flexor retinaculum, is the most common entrapment neuropathy of the upper limb. After a failure of conservative treatments, such as non-steroidal anti-inflammatory drugs (NSAIDs) and splinting, interventional techniques are required. Hydrodissection is an injection technique that separates the nerve from the surrounding tissue. Although this technique is gaining ground in modern medicine, the state-of-the-art literature is lacking a clear protocol or approach for hydrodissection for CTS. In this article, we describe a safe, minimally invasive, effective, and easy-to-use ultrasound-guided hydrodissection technique for CTS.

The morphological stenosis pattern of the suprascapular notch is revealed yielding higher incidence in the discrete type and elucidating the inevitability of osteoplasty in horizontally oriented stenosis

PURPOSE

To identify the morphological patterns of suprascapular notch stenosis.

METHODS

Suprascapular notch space capacity was assessed by morphometric analysis of 333 dry scapulae. Suprascapular notch parameters-superior transverse distance, middle width, depth, medial border length and lateral border length-were measured. The probable suprascapular notch stenosis was referenced by (1) comparing each obtained parameter measurement to the range of the suprascapular nerve diameter, and (2) quantifying the reduced parameters. Finally, the morphological pattern was determined based on the collective reduction of the parameters and their alignments.

RESULTS

Five types of suprascapular notch based on depth to superior transverse distance ratio were identified and assessed. Type-I showed low incidence of stenosis (6/333) and low frequency within type (6/28) with potential risk of horizontal compression. Type-II showed relatively low incidence of stenosis (9/333) and low frequency within type (9/50) with undetermined pattern. Type-III showed relatively higher incidence of stenosis (47/333) but low frequency within type (47/158) with potential risk of vertical compression. Type-IV (foramen) showed low incidence of stenosis (6/333) and relatively lower frequency within type (6/26) with potential risk of encircled compression. Finally, type-V (discrete) showed relatively high incidence of stenosis (40/333) and high frequency within type (40/71) with potential risk of vertical compression. The suprascapular notch was found to be stenosed beyond its capacity to accommodate the suprascapular nerve in 49/333. Type-V is at most risk followed by Type-III.

CONCLUSIONS

Suprascapular notch stenosis takes three morphological patterns: horizontal, vertical or mixed. An osteoplasty of suprascapular notch margins may be required beside the common surgical approach of the superior transverse scapular ligamentectomy.

Common Compression Neuropathies

Compression neuropathies, also known as entrapment neuropathies, are common neurologic conditions seen in medicine. These often are due to mechanical injury, either compression or stretch of the affected nerve, and initially result in focal demyelinating changes. If left untreated, secondary axonal injury and lasting disability can result. Patients typically present with pain, sensory changes, and potentially weakness in the distribution of the affected nerve; therefore, a basic knowledge of neuromuscular anatomy is necessary to identify these conditions. Initial treatment of mild to moderate cases often is conservative. In severe cases or those refractory to conservative therapy, surgery should be considered.

Lower extremity entrapment neuropathies

Entrapment neuropathies are frequently encountered by rheumatologists, not only because they are common but also because of their association with certain rheumatological and systemic disorders. Recognizing entrapment neuropathy early can help avoid progressive neurological deficits, as well as facilitate appropriate treatment measures, which can effectively minimize a patient's symptoms. Entrapment neuropathies may be distinguished from other musculoskeletal causes of lower extremity pain by identifying characteristic patterns of weakness and/or sensory loss, so a focused bedside neurological examination is key for diagnosis. In this chapter, we review the most common entrapment neuropathies that occur in the lower extremities, review the relevant neuroanatomy, outline a diagnostic approach to distinguish them from other mimics, and highlight appropriate management options.

Current and future applications of ultrasound imaging in peripheral nerve disorders

Neuromuscular ultrasound (NMUS) is a rapidly evolving technique used in neuromuscular medicine to provide complimentary information to standard electrodiagnostic studies. NMUS provides a dynamic, real time assessment of anatomy which can alter both diagnostic and management pathways in peripheral nerve disorders. This review describes the current and future techniques used in NMUS and details the applications and developments in the diagnosis and monitoring of compressive, hereditary, immune-mediated and axonal peripheral nerve disorders, and motor neuron diseases. Technological advances have allowed the increased utilisation of ultrasound for management of peripheral nerve disorders; however, several practical considerations need to be taken into account to facilitate the widespread uptake of this technique.

Quality of life effects of pain from para-lumbar- and lower extremity entrapment syndrome and carpal tunnel syndrome and comparison of the effectiveness of surgery

INTRODUCTION

We compared the preoperative quality of life (QOL) of patients with carpal tunnel syndrome, lower extremity-, and para-lumbar entrapment syndrome, and the effect of surgery on their QOL.

PATIENTS AND METHODS

We prospectively enrolled 66 consecutive patients who underwent surgery for carpal tunnel syndrome (group 1, n = 23), lower extremity entrapment syndrome (group 2, n = 22), and para-lumbar entrapment syndrome (group 3, n = 21). Their pre- and postoperative overall health status was assessed on the Medical Outcomes Study Short-Form 36 Health Survey, v2 (SF-36).

RESULTS

Except for the mental component summary, the preoperative score for items rated on the SF-36 was significantly lower in group 3 than in groups 1 and 2 (p < 0.05). In all 66 patients, the scores for bodily pain (BP) and the physical component summary (PCS) were significantly lower (p < 0.05) than the national standard, as was the score for physical functioning (PF) in groups 2 and 3. After surgery, PF of group 2 and PF, BP, and PCS of group 3 improved significantly (p < 0.05).

CONCLUSION

The detrimental QOL effects are stronger in patients with para-lumbar- or lower extremity entrapment syndrome than in patients with carpal tunnel syndrome.

Carpal tunnel sonography

Carpal tunnel syndrome (CTS) is the most frequent entrapment neuropathy of peripheral nerves, with an incidence of 1-3 patients in 1000. CTS typically occurs between 45 and 60 years of age, and it is more frequent in women than in men. The main cause of CTS is chronic compression of the median nerve and ischemic suffering secondary to increased pressure in the carpal tunnel. There are many possible causes of CTS, which can be differentiated into idiopathic causes, which include most cases, and secondary causes. Classical CTS diagnosis is based on the patient's clinical examination and electrophysiological tests, such as electromyography and nerve conduction studies. The latter are helpful for determining the site of nerve compression, assessing its severity, monitoring the course of the disease after therapy, and excluding other causes of median nerve pain, such as cervical radiculopathies, brachial plexopathies, polyneuropathy, or other forms of mononeuropathies. However, clinical examination and electrophysiological tests are not able to differentiate idiopathic forms from secondary forms of CTS, and discrepancies are possible between clinical examination and electrophysiological tests (false negatives). Ultrasound examination is able to recognize most of the secondary forms of CTS. It can evaluate the morphological alterations of the nerve and correlate them with the severity of nerve suffering in all cases, even idiopathic ones, with a sensitivity and specificity equal to those of electrophysiological tests. It can also highlight some anatomical predisposing variants or conditions that may represent contraindications to minimally invasive treatments. Ultrasound examination also plays a fundamental role in evaluating patients with an unfavorable outcome after surgical treatment.

Implantable wireless device for study of entrapment neuropathy

BACKGROUND

Disease processes causing increased neural compartment pressure may induce transient or permanent neural dysfunction. Surgical decompression can prevent and reverse such nerve damage. Owing to insufficient evidence from controlled studies, the efficacy and optimal timing of decompression surgery remains poorly characterized for several entrapment syndromes.

NEW METHOD

We describe the design, manufacture, and validation of a device for study of entrapment neuropathy in a small animal model. This device applies graded extrinsic pressure to a peripheral nerve and wirelessly transmits applied pressure levels in real-time. We implanted the device in rats applying low (under 100 mmHg), intermediate (200-300 mmHg) and high (above 300 mmHg) pressures to induce entrapment neuropathy of the facial nerve to mimic Bell's palsy. Facial nerve function was quantitatively assessed by tracking whisker displacements before, during, and after compression.

RESULTS

At low pressure, no functional loss was observed. At intermediate pressure, partial functional loss developed with return of normal function several days after decompression. High pressure demonstrated complete functional loss with incomplete recovery following decompression. Histology demonstrated uninjured, Sunderland grade III, and Sunderland grade V injury in nerves exposed to low, medium, and high pressure, respectively.

COMPARISON WITH EXISTING METHODS

Existing animal models of entrapment neuropathy are limited by inability to measure and titrate applied pressure over time.

CONCLUSIONS

Described is a miniaturized, wireless, fully implantable device for study of entrapment neuropathy in a murine model, which may be broadly employed to induce various degrees of neural dysfunction and functional recovery in live animal models.

Recent Advances in the Understanding and Management of Carpal Tunnel Syndrome: a Comprehensive Review

PURPOSE OF REVIEW

Carpal tunnel syndrome (CTS) is an entrapment neuropathy that involves the compression of the median nerve at the wrist and is considered the most common of all focal entrapment mononeuropathies. CTS makes up 90% of all entrapment neuropathies diagnosed in the USA and affects millions of Americans.

RECENT FINDINGS

Age and gender likely play a role in the development of CTS, but additional studies may further elucidate these associations. Of known associated risk factors, diabetes mellitus seems to have the greatest association with CTS. One of the most commonly reported symptoms in CTS is a "pins-and-needles" sensation in the first three fingers and nocturnal burning pain that is relieved with activity upon waking. Treatment for CTS is variable depending on the severity of symptoms. Conservative management of CTS is usually considered first-line therapy. In cases of severe sensory or motor deficit, injection therapy or ultimately surgery may then be considered. Still CTS is often difficult to treat and may be reoccurring. Novel treatment modalities such as laser and shockwave therapy have demonstrated variable efficacy though further studies are needed to assess for safety and effect. Given the unknown and potentially complex etiology of CTS, further studies are needed to explore combinations of diagnostic and therapeutic modalities.

Inguinal segmental nerve conduction of the lateral femoral cutaneous nerve in healthy controls and in patients with meralgia paresthetica

A common entrapment site of the lateral femoral cutaneous nerve (LFCN) is in the vicinity of the inguinal ligament. However the more distal segment of this nerve can also be affected. Electrophysiological evaluation of this nerve is difficult. Additionally, available methods have failed in the lesion localization of LFCN. In this study, we aimed to evaluate nerve conduction study in different segments of the LFCN. Nerve action potentials of the LFCN were recorded with distal surface electrodes from a relatively distant point (about 30 cm caudal to the spina iliaca anterior superior). An electrical stimulus was given both 10 cm distal to the SIAS and at the level of the SIAS. Inguinal segmental and distal sensory nerve conduction studies were performed on the LFCN. Thirty-eight healthy controls and 34 patients with meralgia paresthetica (MP) were analyzed by this method. All patients with MP showed electrophysiological abnormalities. Slowed sensory conduction on the inguinal channel (p:0.0001) and loss of response were the most frequent abnormalities (44.7% and 31.6%). In one patient, the only abnormality was slowed sensory conduction at the distal site. Our findings suggest that this technique can help in diagnosis and lesion localization in MP.

Middle cluneal nerve entrapment mimics sacroiliac joint pain

BACKGROUND

Sacroiliac joint (SIJ)-related pain is associated with low back- and buttock pain and the SIJ score is diagnostically useful because it helps to differentiate between SIJ-related pain and pain due to other factors such as lumbar disc herniation and lumbar spinal canal stenosis. Middle cluneal nerve (MCN) entrapment (MCN-E) can produce pain involving the lower back and buttocks. Therefore, the origin of the pain must be identified. We successfully treated patients with a high SIJ score whose pain was attributable to MCN-E.

METHODS

Between August 2016 and June 2017, we treated 40 patients with non-specific low back pain. Among them, 18 (45%) presented with a positive SIJ score. Although SIJ treatment was unsuccessful in 4 of these patients, they responded to MCN-E treatment.

RESULTS

All 4 patients reported tenderness at the site of the sacrotuberous ligament (STL); 3 were positive for the one-finger test and experienced pain while sitting in a chair. The effect of SIJ block was inadequate in the 4 patients. As they reported severe pain at the trigger point in the area of the MCN, we performed MCN blockage. It resulted in pain control. However, in 1 patient, the effect of MCN block was transient and required MCN neurolysis. At the last visit, our patients' symptoms were significantly improved; their average numerical rating scale score fell from 8.3 to 1.0, their Roland-Morris Disability Questionnaire score fell from 12.8 to 0.3, and their average Japanese Orthopaedic Association score rose from 12.5 to 19.5.

CONCLUSIONS

In patients with suspected SIJ-related pain, the presence of MCN-E must be considered when the effect of SIJ block is unsatisfactory.

Imaging of Microhemodynamics in Peripheral Nerves by Contact Endoscope

BACKGROUND

Entrapment neuropathies include a wide field of locations. In most cases, the microsurgical decompression is still the therapy of choice. However, the role of venous stasis and ischemia is still discussed controversially. Here the authors evaluated the visualization of microvessels and the microperfusion at peripheral nerves with a contact endoscope during the surgical decompression for the first time.

METHODS

Eight patients were subjected to endoscopic or endoscopically assisted peripheral nerve decompression. In 3 patients with nerve tumors, the tumor carrying nerve was inspected endoscopically proximal and distal to the tumor site before and after resection. Microcirculation was assessed by a contact endoscope, allowing a 150-fold magnification, at superficial areas proximal and distal to the compression site. The electronically stored records were analyzed retrospectively using image processing software. Vessel diameter, red blood cell velocity, and blood flow, before and after decompression, were extracted.

RESULTS

The contact endoscope was easy to handle intraoperatively without problems. All minimally invasive procedures were performed without complications. In the offline computer-assisted analysis, single arterioles and veins were visualized showing decreased red blood cell velocity prior to decompression. After surgical treatment, a statistically significant increase of blood flow was observed.

CONCLUSIONS

Basically, the application of a contact endoscope for visualization of peripheral nerves' microcirculation is feasible. The observed effect of increased blood flow after decompression should be compared with the clinical outcome in a further prospective randomized study.

Neurosurgical treatment of leprosy neuropathy in a low-incidence, European country

INTRODUCTION

Leprosy is nowaday increasingly encountered in non-endemic countries. Nerve involvement is common. Swelling of the nerves may lead to entrapment neuropathy causing pain and neurological deficits. Delay in diagnosis and treatment may lead to loss of chance of improvement. Surgical decompression in conjunction with medical therapy allows relief of symptoms.

METHODS

We present a retrospective series of 21 patients surgically treated in our center for leprosy entrapment neuropathy. We report presentation, treatment, and outcome at follow-up including a brief literature review.

RESULTS

Twenty-one patients were treated for nerve entrapments in four different anatomical districts. We reported good clinical outcomes mainly in motor deficits but also in improvement of sensitive deficits and pain symptoms. We did not experience surgical complications.

DISCUSSION

Although there is a lack of high-quality prospective studies comparing medical and surgical treatment of leprosy neuropathy, benefits of surgery are widely reported in series and case reports from endemic countries. There is scant literature from low-incidence countries even if leprosy incidence is nowaday increasing in these countries and will likelihood further increase in the future. Our results are in line with the literature presenting good outcomes after surgery.

CONCLUSION

We believe that a precise knowledge of the pathology and its management is crucial also for physicians who work in low-incidence countries to maximize healing chances with timely diagnosis and treatment.

Anatomical Variants of "Short Head of Biceps Femoris Muscle" Associated with Common Peroneal Neuropathy in Korean Populations : An MRI Based Study

Objective

In Asians, kneeling and squatting are the postures that are most often induce common peroneal neuropathy. However, we could not identify a compatible compression site of the common peroneal nerve (CPN) during hyper-flexion of knees. To evaluate the course of the CPN at the popliteal area related with compressive neuropathy using magnetic resonance imaging (MRI) scans of healthy Koreans.

Methods

1.5-Tesla knee MRI scans were obtained from enrolled patients and were retrospectively reviewed. The normal populations were divided into two groups according to the anatomical course of the CPN. Type I included subjects with the CPN situated superficial to the lateral gastocnemius muscle (LGCM). Type II included subjects with the CPN between the short head of biceps femoris muscle (SHBFM) and the LGCM. We calculated the thickness of the SHBFM and posterior elongation of this muscle, and the LGCM at the level of femoral condyles. In type II, the length of popliteal tunnel where the CPN passes was measured.

Results

The 93 normal subjects were included in this study. The CPN passed through the “popliteal tunnel” formed between the SHBFM and the LGCM in 36 subjects (38.7% type II). The thicknesses of SHBFM and posterior portions of this muscle were statistically significantly increased in type II subjects. The LGCM thickness was comparable in both groups. In 78.8% of the “popliteal tunnel”, a length of 21 mm to <40 mm was measured.

Conclusion

In Korean population, the course of the CPN through the “popliteal tunnel” was about 40%, which is higher than the Western results. This anatomical characteristic may be helpful for understanding the mechanism of the CPNe by posture.

Anatomic Variation in Patient with Lateral Femoral Cutaneous Nerve Entrapment Neuropathy

BACKGROUND

We report a surgical case of entrapment neuropathy of lateral femoral cutaneous nerve (LFCN) with anatomical variation.

CASE DESCRIPTION

This 53-year-old man had a 10-year history of paresthesia and pain in the right anterolateral thigh exacerbated by prolonged standing and walking. His symptoms improved completely but transiently by LFCN block. The diagnosis was LFCN entrapment. Because additional treatment with drugs and repeat LFCN block was ineffective, we performed surgical decompression under local anesthesia. A nerve stimulator located the LFCN 4.5 cm medial to the anterior superior iliac spine. It formed a sharp curve and was embedded in connective tissue. Proximal dissection showed it to run parallel to the femoral nerve at the level of the inguinal ligament. The inguinal ligament was partially released to complete dissection/release. Postoperatively, his symptoms improved and the numeric rating scale fell from 8 to 1.

CONCLUSION

We report a rare anatomical variation in the course of the LFCN.

Dynamic factors involved in common peroneal nerve entrapment neuropathy

BACKGROUND

Common peroneal nerve (CPN) entrapment neuropathy (CPNEN) is the most common peripheral neuropathy of the lower extremities. The pathological mechanisms underlying CPNEN remain unclear. We sought to identify dynamic factors involved in CPNEN by directly measuring the CPN pressure during stepwise CPNEN surgery.

METHODS

We enrolled seven patients whose CPNEN improved significantly after CPN neurolysis. All suffered intermittent claudication, and the repetitive plantar flexion test, used as a CPNEN provocation test, was positive. During decompression surgery we directly measured the CPN pressure during several decompression steps.

RESULTS

Before CPN decompression, plantar flexion elicited a statistically significant increase in the CPN pressure (from 1.8 to 37.3, p < 0.05), as did plantar extension (from 1.8 to 23.1, p < 0.05). The CPN pressure gradually decreased during step-by-step surgery; it was lowest after resection of the peroneus longus muscle (PLM) fascia.

CONCLUSIONS

Dynamic factors affect idiopathic CPNEN. The CPN pressure decreased at each surgical decompression step, and removal of the PLM fascia resulted in adequate decompression of the CPN. Our findings shed light on the etiology of idiopathic CPNEN and recommend adequate CPNEN decompression procedures.

Pain and compression neuropathy in primary inguinal hernia

PURPOSE

Enlargement of the ilioinguinal nerve at the external inguinal ring is observed in 34% of patients undergoing primary open inguinal herniorrhaphy; in 88% of patients it occurs at the fascial edge where the hernia mushrooms with abdominal pressure. Compression neuropathy occurs near many anatomical nerve constriction sites and is associated with enlargement of the peripheral nerve accompanied by sensory changes.

METHODS

In this prospective study, Carolina Comfort Scale (CCS) questionnaire data was collected for 35 primary hernia repairs. Each patient underwent primary inguinal herniorrhaphy that included ilioinguinal neurectomy. All nerves were sampled proximal to the external inguinal ring. Any nerves with grossly increased overall diameter to any degree distal to the external ring were additionally sampled in the thickened portions. A neuropathologist performed histologic evaluation of the H&E-stained cross sections.

RESULTS

Paired comparison of proximal and distal nerves revealed a greater overall diameter and greater measured nerve-specific diameter in distal nerve segments. Nerves with increased overall diameter were also found to have a statistically significant positive correlation with four of eight pain measures. Additionally, increased nerve-specific diameter correlates with increased pain on four of eight pain values, but age effect on nerve diameter blunts this finding.

CONCLUSIONS

Increased preoperative CCS pain values in primary open inguinal hernia are significantly correlated with gross enlargement of the overall diameter and nerve-specific diameter of the ilioinguinal nerve beyond the external inguinal ring. This is consistent with a compression neuropathy.

Is carpal tunnel syndrome present in acute stroke patients? An investigative study using clinical and imaging screening tools

Carpal tunnel syndrome (CTS) is known to develop post-stroke. Median nerve ultrasound (US) is an inexpensive, effective means of screening. In this prospective feasibility study, we compared the ability of the physical exam, the Boston Carpal Tunnel Questionnaire (BCTQ) and median nerve US to screen for carpal tunnel syndrome (CTS) within 72hours of stroke onset. We enrolled 24 consecutive patients. Using US, 19 (79%, p=0.0386) of the 24 patients screened positive for CTS on the paretic side and 20 (83%, p=0.0042) on the nonparetic side. With clinical examination, only 11 out of 24 (46%) screened positive for CTS on the paretic side and 8 (33%) on the nonparetic side. The BCTQ did not predict CTS. US can be an effective screening tool post-stroke. Further research is needed to determine specificity and efficacy compared to electrodiagnostic testing in this population.

The strain - Counter strain technique in the management of anterior interosseous nerve syndrome: A case report

Anterior interosseous nerve syndrome (AINS) is a proximal median nerve neuropathy affecting the forearm. Trigger points in the anterior compartment of the forearm may cause compression of the anterior interosseous nerve (AIN) which, in turn, may result in muscle weakness. Here we present the case of a 37-year-old female who complained of an abnormal pen grip while writing. Clinical examination (observation, palpation, pincer grip strength) showed weak pincer grip strength, an active trigger point in the middle of the anterior forearm and a positive circle sign. Her treatment course included cryomassage, neural mobilization, transcutaneous electrical nerve stimulation (TENS) and the strain-counter strain (SCS) technique four times a week for two weeks. On follow-up, the patient reported an inactive trigger point on palpation, improvement in her handwriting and improved pincer (fingertip pinch) grip strength in pounds (lbs) as recorded by the Baseline Hydraulic Pinch Gauge. This case report explored the effectiveness of SCS as an important adjunct to other conservative treatments for entrapment neuropathies. SCS has also shown its potential to improve muscle strength.

Lunate dislocation causing median nerve entrapment

Lunate dislocation is an uncommon injury occurring in young adults due to high-energy trauma. The volar displacement of the bone may result in compression of the median nerve within the carpal tunnel and is an uncommon cause of entrapment neuropathy.

The Relationship between Nerve Conduction Study and Clinical Grading of Carpal Tunnel Syndrome

INTRODUCTION

Carpal Tunnel Syndrome (CTS) is the most common nerve entrapment. Subjective sensory symptoms are common place in patients with CTS, but sometimes they are not supported by objective findings in the neurological examination. Electrodiagnostic (EDx) studies are a valid and reliable means of confirming the diagnosis. The amplitudes along with the conduction velocities of the sensory nerve action potential and motor nerve action potential reflect the functional state of axons, and are useful parameters and complement the clinical grading in the assessment of severity of CTS.

AIM

To conduct median nerve sensory and motor conduction studies on patients with carpal tunnel syndrome and correlate the relationship between nerve conduction study parameters and the clinical severity grading.

MATERIALS AND METHODS

Based on clinical assessment, the study patients were divided into 03 groups with mild CTS, moderate CTS and severe CTS respectively as per Mackinnson's classification. Median and ulnar nerve conduction studies were performed on bilateral upper limbs of 50 patients with symptoms of CTS and 50 age and sex matched healthy control subjects. The relationship between the clinical severity grade and various nerve conduction study parameters were correlated.

RESULTS

In this prospective case control study, 50 patients with symptoms consistent with CTS and 50 age and sex matched healthy control subjects were examined over a 10 month period. A total of 30 patients had unilateral CTS (right upper limb in 19 and left upper limb in 11) and 20 patients had bilateral CTS. Female to male ratio was 3.54 to 1. Age ranged from 25 to 81 years. The mean age at presentation was 49.68±11.7 years. Tingling paresthesias of hand and first three fingers were the most frequent symptoms 48 (98%). Tinel's and Phalen's sign were positive in 36 (72%) and 44 (88%) patients respectively. The mean duration of symptoms at presentation was 52.68±99.81 weeks. 16 patients (32%) had mild CTS, 25 (50%) had moderate CTS and 9 (18%) had severe CTS clinically. Prolongation of motor latency, latency difference between median and ulnar amplitudes, motor and sensory nerve conduction velocities, sensory latency between median and ulnar nerves, sensory nerve conduction velocities showed significant changes in comparison with controls. Among them sensory latency difference between median and ulnar nerves and sensory nerve conduction velocities are the most sensitive and specific for diagnosing CTS.

CONCLUSION

In this study, there was a graded deterioration of electrophysiological parameters along with the clinical severity grades, thus reiterating the fact that NCS provide additional, independent objective evidence in the diagnosis and severity assessment of CTS. The sensory conductions were more sensitive than motor conductions in assessing CTS.

The Impact of Tarsal Tunnel Syndrome on Cold Sensation in the Pedal Extremities

OBJECTIVE

Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the posterior tibial nerve in the tarsal tunnel. It is not known whether vascular or neuropathic factors are implicated in the cause of a cold sensation experienced by patients. Therefore, we studied the cold sensation in the pedal extremities of patients who did or did not undergo TTS surgery.

METHODS

Our study population comprised 20 patients with TTS (38 feet); 1 foot was affected in 2 patients and both feet in 18 patients. We acquired the toe-brachial pressure index to evaluate perfusion of the sole and toe perfusion under 4 conditions: the at-rest position (condition 1); the at-rest position with compression of the foot dorsal artery (condition 2); the Kinoshita foot position (condition 3); and the Kinoshita foot position with foot dorsal artery compression (condition 4). Patients who reported abatement in the cold sensation during surgery underwent intraoperative reocclusion of the tibial artery to check for the return of the cold sensation.

RESULTS

The toe-brachial pressure index for conditions 1 and 3 averaged 0.82 ± 0.09 and 0.81 ± 0.11, respectively; for conditions 2 and 4, it averaged 0.70 ± 0.11 and 0.71 ± 0.09, respectively. Among the 16 operated patients, the cold sensation in 7 feet improved intraoperatively; transient reocclusion of the tibial artery did not result in the reappearance of the cold sensation.

CONCLUSIONS

Our findings suggest that the cold sensation in the feet of our patients with TTS was associated with neuropathic rather than vascular factors.

Carpal tunnel syndrome: The role of collagen gene variants

INTRODUCTION

The direct causes of idiopathic carpal tunnel syndrome (CTS) are still unknown. It is suggested that pathology of the tendons and other connective tissue structures within the carpal tunnel may play a role in its aetiology. Variants in genes encoding connective tissue proteins, such as type V collagen, have previously been associated with CTS. Since variants within other collagen genes, such as type I, XI and XII collagen, have previously been associated with modulating the risk of musculoskeletal soft tissue injuries, the aim of this study was to determine whether variants within COL1A1, COL11A1, COL11A2 and COL12A1 were associated with CTS.

METHODS

Self-reported Coloured South African participants, with a history of carpal tunnel release surgery (CTS, n=103) and matched control (CON, n=150) participants without any reported history of CTS symptoms were genotyped for COL1A1 rs1800012 (G/T), COL11A1 rs3753841 (T/C), COL11A1 rs1676486 (C/T), COL11A2 rs1799907 (T/A) and COL12A1 rs970547 (A/G).

RESULTS

The TT genotype of COL11A1 rs3753841 was significantly over-represented in the CTS group (21.4%) compared to CON group (7.9%, p=0.004). Furthermore, a trend for the T minor allele to be over-represented in the CTS group (p=0.055) with a significant association when only female participants (p=0.036) were investigated was observed. Constructed inferred pseudo-haplotypes including a previously investigated COL5A1 variant, rs71746744 (-/AGGG), suggest gene-gene interactions between COL5A1 and COL11A1 modulate the risk of CTS.

DISCUSSION

These findings provide further information of the role of the genetic risk factors and the possible role of variations in collagen fibril composition in the aetiology of CTS. Genetic factors could potential be included in models developed to identify indivisuals at risk of CTS. Strategies that target modifiable risk factors to mitigate the effect of non-modifiable risk factors, such as the genetic risk, could be also developed to reduce incidence and morbidity of CTS.

Entrapment of middle cluneal nerves as an unknown cause of low back pain

Entrapment of middle cluneal nerves induces low back pain and leg symptoms. The middle cluneal nerves can become spontaneously entrapped where this nerve pass under the long posterior sacroiliac ligament. A case of severe low back pain, which was completely treated by release of the middle cluneal nerve, was presented. Entrapment of middle cluneal nerves is possibly underdiagnosed cause of low-back and/or leg symptoms. Spinal surgeons should be aware of this clinical entity and avoid unnecessary spinal surgeries and sacroiliac fusion. This paper is to draw attention by pain clinicians in this unrecognized etiology.

The evaluation of vitamin D levels in patients with carpal tunnel syndrome

The aim of this study was to evaluate the relationship between 25-hydroxyvitamin D (25(OH)D) levels and carpal tunnel syndrome (CTS). 25(OH)D levels were checked in 108 consecutive patients with CTS symptoms and 52 healthy controls. All patients underwent nerve conduction studies and completed Boston Carpal Tunnel Questionnaire (BQ) symptom severity and functional status scales to quantify symptom severity, pain status and functional status. There were 57 patients with electrophysiological confirmed CTS (EP+ group) and 51 electrophysiological negative symptomatic patients (EP- group). 25(OH) D deficiency (25(OH)D < 20 ng/ml) was found in 96.1 % of EP- group, in 94.7 % of EP+ group and in 73.8 % of control group. 25(0H) D level was found significantly lower both in EP+ and EP- groups compared to control group (p = 0.006, p < 0.001, respectively). Although mean vitamin D level in EP- group was lower than EP+ group, statistically difference was not significant between EP+ and EP- groups (p = 0.182). BQ symptom severity and functional status scores and BQ pain sum score were not significantly different between EP+ and EP- groups. We found no correlation with 25(OH) D level for BQ symptom severity, functional status and pain sum scores. 25(OH) D deficiency is a common problem in patients with CTS symptoms. As evidenced by the present study, assessment of serum 25(OH)D is recommended in CTS patients even with electrophysiological negative results.

Tunnels and grooves for supraclavicular nerves within the clavicle: review of the literature and clinical impact

Perforation of the clavicle by supraclavicular nerves is a common anatomical variation. This variation has been reported in several studies based on post-mortem, surgical and radiologic findings, with an overall frequency between 1 and 6.6 %. The penetrating branch passes either through a bony tunnel or a groove on the superior surface of the bone. Entrapment neuropathy of the perforating branch is a documented clinical entity reported in the literature. The intraosseous course of the supraclavicular nerves makes them vulnerable to injury in case of clavicular fractures or during surgical manipulations of these fractures. Furthermore, this variation should be taken into account during the interpretation of chest and shoulder radiographs. The purpose of the current study is to perform an extended review of the relevant literature, highlighting the clinical impact of this variation, as well as to incorporate our own findings into them.

Treatment of low back pain in patients with vertebral compression fractures and superior cluneal nerve entrapment neuropathies

BACKGROUND

Superior cluneal nerve entrapment neuropathy (SCN-EN) may contribute to low back pain (LBP). However, it is often misdiagnosed as lumbar spine disorder and poorly understood.

METHODS

Between April 2012 and September 2013, we treated 27 patients (3 men, 24 women; mean age 75.0 years) with LBP due to SCN-EN elicited by vertebral compression fractures. Symptoms were unilateral in 4 patients and bilateral in 23 patients. The interval between symptom onset and treatment averaged 10.8 months; the mean postoperative follow-up period was 19.0 months. The clinical outcomes were assessed utilizing the numeric rating scale (NRS) for LBP, the Japanese Orthopedic Association (JOA) score, and the Roland-Morris Disability Questionnaire (RDQ) before and after treatment (e.g., until the latest follow-up).

RESULTS

LBP in 17 patients was immediately improved by SCN block only. The remaining 10 patients required surgery (involving 18 sites) as SCN blocks were only transiently effective. Operative intervention resulted in the immediate and continued improvement of their LBP. Notably, their NRS decreased from 7.4 to 1.5, their RDQ scores from 19.6 to 7.0, and their JOA scores increased from 10.7 to 20.3.

CONCLUSIONS

In this series, 27 patients with LBP due to SCN-EN responded either to SCN blocks (17 patients) or surgical release of SCN entrapment (10 patients at 18 sites).

Ultrasound Guided Transversus Abdominis Plane Block for Anterior Cutaneous Nerve Entrapment Syndrome

Anterior cutaneous nerve entrapment syndrome (ACNES) is one the most common cause of chronic abdominal wall pain. The syndrome is mostly misdiagnosed, treated wrongly and inadequately. If diagnosed correctly by history, examination and a positive carnett test, the suffering of the patient can be relieved by addressing the cause i.e. local anaesthetic with steroid injection at the entrapment site. Conventionally, the injection is done by landmark technique. In this report, we have described 2 patients who were diagnosed with ACNES who were offered ultrasound guided transverses abdominis plane (TAP) injection who got significant pain relief for a long duration of time.

Meralgia paraesthetica: Ultrasound-guided injection at multiple levels with 12-month follow-up

OBJECTIVES

To evaluate the efficacy of ultrasound (US)-guided injections around the lateral femoral cutaneous nerve (LFCN) at different levels in meralgia paraesthetica (MP) patients.

METHODS

The study was approved by the university ethics committee and informed oral and written consent were obtained from all patients. Between June 2008 and August 2013, 20 patients with symptoms of MP, including nine men (mean age, 61.33 years) and 11 women (mean age 61.18 years), were treated with US-guided injection of steroids along the LFCN at three different levels in a mean of 2.25 sessions. A visual analogue scale (VAS) was used to measure symptoms before, immediately after and 12 months after treatment.

RESULTS

Complete resolution of symptoms was documented in 15/20 patients (mean VAS decreased from 82 to 0), and partial resolution in the remaining five (mean VAS decreased from 92 to 42), which was confirmed at 12-month follow-up. By using the different levels of injection approach overall significantly better symptom relief was obtained (p < 0.05).

CONCLUSION

The outcome of US-guided injection along the LFCN can be further improved by injections at different levels (p < 0.05), which was confirmed at 12-month long-term follow-up.

KEY POINTS

Meralgia paraesthetica is an entrapment neuropathy of the lateral femoral cutaneous nerve. Ultrasound proved effective in diagnosis and in guiding injection therapy. Injection at the anterior superior iliac spine has been used previously. Multiple injections along the nerve course were used in this study. Long-term follow-up (12 months) confirmed the results.

Entrapment neuropathy of the wrist, forearm, and elbow

This review discusses key diagnostic points and treatment guidelines for compression neuropathies of the wrist, forearm, and elbow. Recent treatment progress is reviewed, controversies are highlighted, and consensus is summarized. Limited or mini-open releases and endoscopic carpal tunnel releases are considered equally safe and efficient. Both methods are currently mainstays of surgical treatment.

Decompression of the sciatic nerve entrapment caused by post-inflammatory scarring

A rare case of chronic pain of entrapment neuropathy of the sciatic nerve successfully relieved by surgical decompression is presented. A 71-year-old male suffered a chronic right buttock pain of duration of 7 years which radiating to the right distal leg and foot. His pain developed gradually over one year after underwenting drainage for the gluteal abscess seven years ago. A cramping buttock and intermittently radiating pain to his right foot on sitting, walking, and voiding did not respond to conventional treatment. An MRI suggested a post-inflammatory adhesion encroaching the proximal course of the sciatic nerve beneath the piriformis as it emerges from the sciatic notch. Upon exploration of the sciatic nerve, a fibrotic tendinous scar beneath the piriformis was found and released proximally to the sciatic notch. His chronic intractable pain was completely relieved within days after the decompression. However, thigh weakness and hypesthesia of the foot did not improve. This case suggest a need for of more prompt investigation and decompression of the chronic sciatic entrapment neuropathy which does not improve clinically or electrically over several months.

Electrodiagnostic approach in entrapment neuropathies of the median and ulnar nerves

OBJECTIVE

The present study's aim was to analyze the late responses' parameters in order to determine the utility of each one.

METHODS

The study, conducted on a total of 325 patients with entrapment neuropathy of the median nerve and 36 with entrapment neuropathy of the ulnar nerve, included the bilateral evaluation of the median and the ulnar nerve and analysis of 20 F-wave and 4 A-wave parameters.

RESULTS

The authors emphasize the necessity of bilateral examination and that of examining the ipsilateral ulnar/median nerve, such as to calculate the difference in F-wave average latency of the median/ulnar and the ipsilateral ulnar/median nerve. This was the most sensitive parameter studied, altered in more than 70% of cases, significantly in more cases than when using only the M-wave distal latency. Also there was a statistically significant correlation between patient age and F-wave latency.

CONCLUSIONS

The completed research yielded the recommendation for F-wave parameter studies to include the difference in F-wave average latency of the median/ulnar and the ipsilateral ulnar/median nerve. This parameter was also included in the composite score, along with the recommendations of the American Academy of Emergency Medicine (AAEM).

Anatomical variations of brachial artery - its morphology, embryogenesis and clinical implications

BACKGROUND

Accurate knowledge of variation pattern of the major arteries of upper limb is of considerable practical importance in the conduct of reparative surgery in the arm, forearm and hand however brachial artery and its terminal branches variations are less common.

AIM

Accordingly the present study was designed to evaluate the anatomical variations of the brachial artery and its morphology, embryogenesis and clinical implications.

MATERIALS AND METHODS

In an anatomical study 140 upper limb specimens of 70 cadavers (35 males and 35 females) were used and anatomical variations of the brachial artery have been documented.

RESULTS

Accessory brachial artery was noted in eight female cadavers (11.43%). Out of eight cadavers in three cadavers (4.29%) an unusual bilateral accessory brachial artery arising from the axillary artery and it is continuing in the forearm as superficial accessory ulnar artery was noted. Rare unusual variant unilateral accessory brachial artery and its reunion with the main brachial artery in the cubital fossa and its variable course in relation to the musculocutaneous nerve and median nerve were also noted in five cadavers (7.14%).

CONCLUSION

As per our knowledge such anatomical variations of brachial artery and its terminal branches with their relation to the surrounding structures are not reported in the modern medical literature. An awareness of such a presence is valuable for the surgeons and radiologists in evaluation of angiographic images, vascular and re-constructive surgery or appropriate treatment for compressive neuropathies.

The BGN and ACAN genes and carpal tunnel syndrome

The causes of idiopathic carpal tunnel syndrome (CTS) remain unknown and the involvement of the tendons within the carpal tunnel structure in the aetiology of CTS cannot be excluded. Variants within the COL5A1 gene, an important regulator of fibril assembly in tendons, have previously been associated with modulating the risk of CTS. Furthermore, proteoglycans are also important structural components of tendons and variants within the aggrecan gene are associated with musculoskeletal soft tissue injuries. The aim of this study was to determine whether ACAN and BGN variants are associated with CTS. Self-reported Coloured participants (n=99), with a history of CTS release surgery (CTS), and 136 control participants, with no history of CTS symptoms (CON), were genotyped for ACAN rs1516797(G/T) and BGN rs1126499(C/T) variants. The BGN CC genotype was significantly over-represented (p=0.0498; OR=0.545, 95% CI=0.30-0.99) in the CON group (71.8%) versus the CTS (58.1%) group. When the previously reported associated COL5A1 genotypes were included in the analysis, COL5A1 and BGN gene-gene interactions were also shown to significantly modulate the risk of CTS in females. In conclusion this is the first study to report that variants within the BGN gene, independently and by interacting with COL5A1 variants, are associated with CTS. Further studies are required to replicate these findings.

Reappraising entrapment neuropathies--mechanisms, diagnosis and management

The diagnosis of entrapment neuropathies can be difficult because symptoms and signs often do not follow textbook descriptions and vary significantly between patients with the same diagnosis. Signs and symptoms which spread outside of the innervation territory of the affected nerve or nerve root are common. This Masterclass provides insight into relevant mechanisms that may account for this extraterritorial spread in patients with entrapment neuropathies, with an emphasis on neuroinflammation at the level of the dorsal root ganglia and spinal cord, as well as changes in subcortical and cortical regions. Furthermore, we describe how clinical tests and technical investigations may identify these mechanisms if interpreted in the context of gain or loss of function. The management of neuropathies also remains challenging. Common treatment strategies such as joint mobilisation, neurodynamic exercises, education, and medications are discussed in terms of their potential to influence certain mechanisms at the site of nerve injury or in the central nervous system. The mechanism-oriented approach for this Masterclass seems warranted given the limitations in the current evidence for the diagnosis and management of entrapment neuropathies.

Peripheral neuropathy: clinical and electrophysiological considerations

This article is a primer on the pathophysiology and clinical evaluation of peripheral neuropathy for the radiologist. Magnetic resonance neurography has utility in the diagnosis of many focal peripheral nerve lesions. When combined with history, examination, electrophysiology, and laboratory data, future advancements in high-field magnetic resonance neurography may play an increasingly important role in the evaluation of patients with peripheral neuropathy.

Neurolysis for meralgia paresthetica

Objective

Meralgia paresthetica (MP) is a syndrome of pain and/or dysesthesia in the anterolateral thigh that is caused by an entrapment of the lateral femoral cutaneous nerve (LFCN) at its pelvic exit. Despite early accounts of MP, there is still no consensus concerning the effectiveness of neurolysis or transaction treatments in the long-term relief for medically refractory patients with MP. We retrospectively analyzed available long-term results of LFCN neurolysis for medically refractory MP in an effort to clarify this issue.

Methods

During the last 7 years, 11 patients who had neurolysis for MP were enrolled in this study. Nerve entrapment was confirmed preoperatively by electrophysiological studies or a positive response to local anesthetic injection. Decompression of the LFCN was performed at the level of the iliac fascia, inguinal ligament, and fascia of the thigh distally. The outcome of surgery was assessed 8 weeks after the procedure followed at regular intervals if symptoms persisted.

Results

Twelve decompression procedures were performed in 11 patients over a 7-year period. The average duration of symptoms was 8.5 months (range, 4-15 months). The average follow-up period was 33 months (range, 12-60 months). Complete and partial symptom improvement were noted in nine (81.8%) and two (18.2%) cases, respectively. No recurrence was reported.

Conclusion

Neurolysis of the LFCN can provide adequate pain relief with minimal complications for medically refractory MP. To achieve a good outcome in neurolysis for MP, an accurate diagnosis with careful examination and repeated blocks of the LFCN, along with electrodiagnosis seems to be essential. Possible variation in the course of the LFCN and thorough decompression along the course of the LFCN should be kept in mind in planning decompression surgery for MP.

Compressive neuropathy in the upper limb

Entrampment neuropathy or compression neuropathy is a fairly common problem in the upper limb. Carpal tunnel syndrome is the commonest, followed by Cubital tunnel compression or Ulnar Neuropathy at Elbow. There are rarer entities like supinator syndrome and pronator syndrome affecting the Radial and Median nerves respectively. This article seeks to review comprehensively the pathophysiology, Anatomy and treatment of these conditions in a way that is intended for the practicing Hand Surgeon as well as postgraduates in training. It is generally a rewarding exercise to treat these conditions because they generally do well after corrective surgery. Diagnostic guidelines, treatment protocols and surgical technique has been discussed.