The double crush in nerve entrapment syndromes

Migraine Surgery at the Frontal Trigger Site: An Analysis of Intraoperative Anatomy

BACKGROUND

The development of migraine headaches may involve the entrapment of peripheral craniofacial nerves at specific sites. Cadaveric studies in the general population have confirmed potential compression points of the supraorbital and supratrochlear nerves at the frontal trigger site. The authors' aim was to describe the intraoperative anatomy of the supraorbital and supratrochlear nerves at the level of the supraorbital bony rim in patients undergoing frontal migraine surgery and to investigate associated pain.

METHODS

PATIENTS: scheduled for frontal-site surgery were enrolled prospectively. The senior author (W.G.A.) evaluated intraoperative anatomy and recorded variables using a detailed form and operative report. The resulting data were analyzed.

RESULTS

One hundred eighteen sites among 61 patients were included. The supraorbital nerve traversed a notch in 49 percent, a foramen in 41 percent, a notch plus a foramen in 9.3 percent, and neither a notch nor a foramen in one site. The senior author noted macroscopic nerve compression at 74 percent of sites. Reasons included a tight foramen in 24 percent, a notch with a tight band in 34 percent, and supraorbital and supratrochlear nerves emerging by means of the same notch in 7.6 percent or by means of the same foramen in 4.2 percent. Preoperative pain at a site was significantly associated with nerve compression by a foramen.

CONCLUSIONS

The intraoperative anatomy and cause of nerve compression at the frontal trigger site vary greatly among patients. The authors report a supraorbital nerve foramen prevalence of 50.3 percent, which is greater than in previous cadaver studies of the general population. Lastly, the presence of pain at a specific site is associated with macroscopic nerve compression.

Postsurgical Neuropathy: A Descriptive Review

Postsurgical neuropathies represent an infrequent but potentially devastating complication of surgery that may result in significant morbidity with medicolegal implications. Elucidation of this phenomenon has evolved over the past few decades, with emerging evidence for not only iatrogenic factors contributing to this process but also inflammatory causes. This distinction can be important; for instance, cases in which inflammatory etiologies are suspected may benefit from further investigations including nerve biopsy and may benefit from treatment in the form of immunotherapy. In contrast, postsurgical neuropathies due to perioperative causes including anesthesia, traction, compression, and transection will not benefit in the same manner. This article summarizes early and current literature surrounding the frequency of new neurologic deficits after various surgical types, potential causes including anatomical and inflammatory considerations, and roles for treatment. To capture the scope of the issue, a literature review was conducted for human studies in English via MEDLINE and EMBASE from January 1, 1988 to March 31, 2018. Search terms included anesthesia and/or surgical procedures, operative, peripheral nervous system diseases, trauma, mononeuropathy, polyneuropathy, peripheral nervous system, nerve compression, neuropathy, plexopathy, postoperative, postsurgical, perioperative, complication. We excluded case series with less than 10 patients and review papers. We then narrowed the studies to those presented highlighting key concepts in postsurgical neuropathy.

An Exploratory Randomized Trial of Physical Therapy for the Treatment of Chemotherapy-Induced Peripheral Neuropathy

Background. Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of taxane treatment and cannot currently be prevented or adequately treated. Physical therapy is often used for neural rehabilitation following injury but has not been evaluated in this patient population. Methods. Single-blind, randomized controlled exploratory study compared standard care to a physical therapy home program (4 visits) throughout adjuvant taxane chemotherapy for stage I-III patients with breast cancer (n = 48). Patient questionnaires and quantitative sensory testing evaluated the treatment effect throughout chemotherapy to 6 months post treatment. Nonrandomized subgroup analysis observed effect of general exercise on sensory preservation comparing those reporting moderate exercise throughout chemotherapy to those that did not exercise regularly. Clinical Trial Registration. clinicaltrials.gov (NCT02239601). Results. The treatment group showed strong trends toward less pain (odds ratio [OR] 0.41, 95% confidence interval [CI] 0.17-1.01; P = .053) and pain decreased over time (OR 0.85, 95% CI 0.76-0.94; P = .002). Pain pressure thresholds (P = .034) and grip dynamometry (P < .001) were improved in the treatment group. For the nonrandomized subgroup analysis, participants reporting general exercise had preservation of vibration (Left P = .001, Right P = .001) and normal heat pain thresholds (Left P = .021, Right P = .039) compared with more sedentary participants. Conclusion. Physical therapy home program may improve CIPN pain in the upper extremity for patients with breast cancer, and general exercise throughout chemotherapy treatment was observed to have correlated to preservation of sensory function. Further research is required to confirm the impact of a physical therapy home program on CIPN symptoms.

Not everything is as it seems

We report a case of a patient operated for shoulder rotator cuff injury under interscalene brachial plexus block and general anesthesia, who developed neurological deficit in the nonoperative upper limb in the immediate postoperative period. As our patient developed neurological deficit on the nonoperative side, it was clear from the beginning that neither the nerve block nor the operative procedure was responsible for it. However, had he developed neurological symptoms on the operative side after having a peripheral nerve block, it would have possibly delayed the timely investigation and diagnosis. This case report underlines the need to keep an open mind when investigating neurological symptoms arising in the perioperative period, rather than assuming it to be secondary to either nerve block or as a complication of surgical procedure.

Role of fasciae around the median nerve in pathogenesis of carpal tunnel syndrome: microscopic and ultrasound study

This study investigated the connections between the median nerve paraneural sheath and myofascial structures near it, from both macroscopic and microscopic points of view. Four samples of median nerve and surrounding tissues were excised from nine non-embalmed upper limbs for microscopic analysis. Ultrasound images were analysed in 21 healthy subjects and 16 carpal tunnel syndrome patients to evaluate median nerve transversal displacement during finger motion at carpal tunnel and forearm levels. An anatomical continuity between epimysium and paraneural sheath and a reduction of paraneural fat tissue from proximal to distal was found in all samples. Median nerve displacements at both levels were significantly reduced in carpal tunnel syndrome subjects (P < 0.001). It was observed that the median nerve is not an isolated structure but is entirely connected to myofascial structures. Therefore, unbalanced tension of epimysial fasciae can affect the paraneural sheath, limiting nerve displacement, and consequently this must be included in carpal tunnel syndrome pathogenesis.

Demographics of Patients Undergoing Carpal Tunnel Release in an Urban Tertiary Hospital in Malaysia

Introduction: Carpal tunnel syndrome (CTS) is the most commonly encountered neuropathy. The entrapment of the median nerve at the wrist can be corrected with a carpal tunnel release (CTR) procedure. The objective of this retrospective study was to determine the demographic, medical, and surgical characteristics of the patients with CTS who presented for CTR surgery in a tertiary hospital in Malaysia. Materials and Methods: Malaysians patients with CTS who had undergone a CTR during the period from 1st June 2017 to 31st December 2017 were enrolled into the study. Each patient had a minimum follow-up of three months. The demographic data of age, gender, race and occupation, and the comorbid illnesses and associated risk factors were recorded. The prevalence and occurrence of CTS in the dominant or non-dominant hand and the effectiveness of surgical intervention were also noted. Data was collected, analysed and stored in Microsoft Excel and SPSS 25. Results: There was a total of 76 cases of CTR surgeries done in 62 patients in the study. Eighty percent of the patients were female, and most of the patients belonged to the age group of 41-60 years. Malays constituted 74.2% of the patients, and 34% were housewives. Hypertension, dyslipidaemia and diabetes mellitus were the three major comorbidities. Cervical spondylosis was seen in one-fourth of the patients. Bilateral hand involvement was present in 54.8% of patients. 59.7% of CTR surgery was done on the dominant hand alone, 17.7 % CTR on the non-dominant hand alone and 22.6% CTR on both hands. Numbness and pain (50%) were the predominant presenting symptoms. The most positive signs were the Durkan test (77.6%), followed by the Tinel sign at the carpal tunnel and the Phalen's test. At follow-up, three months or more, after the surgery, 75% of the patients showed a satisfactory improvement. Conclusion: Patients, who had undergone CTR, had a higher prevalence of pre-morbid conditions, and a quarter of them presented with associated cervical spondylosis. The most common presentation was a combination of numbness and pain. Many obtained satisfactory improvement post-surgery and thus open surgery could be considered a reliable treatment for CTS.

Quantitative sensory profiles of upper extremity chemotherapy induced peripheral neuropathy: Are there differences in sensory profiles for neuropathic versus nociceptive pain?

Aims: The aim of this study was to define the sensory phenotypes of taxane-induced peripheral neuropathy (TIPN) between neuropathic and nonneuropathic symptoms in a breast cancer population to identify future targets for mechanism-based pain management.

Methods: Participants (n = 48) with stage I–III breast cancer. Self-report questionnaires and quantitative sensory testing were used to assess sensory symptoms. The self-report version of the Leeds Assessment for Neuropathic Symptoms and Signs (S-LANSS) divided the groups into neuropathic and nonneuropathic sensory phenotypes. In total, five visits over approximately 8 months assessed each participant from pre-chemotherapy to 6 months post-chemotherapy.

Results: Out of 191 nerve assessments, 150 had an S-LANSS <12 defined as “nonneuropathic” and 41 scored >12, which was defined as “neuropathic.” Numeric Pain Rating Scale (NPRS) was analyzed based on percentages of those experiencing 1+ pain (graded 1/10 or higher) versus no pain. The neuropathic group had 82.9% of 1+ pain vs. 28.7% in the nonneuropathic group (odds ratio = 7.49; 95% confidence interval, 2.76–20.3; P = 0.001). The neuropathic group reported impaired function on the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire (P = 0.002). Heat pain threshold resulted in statistical differences for the left hand but not the right hand in the neuropathic group (P = 0.05). No other quantitative data on warm/cool or cold or vibration demonstrated sensory differences between the groups.

Conclusions: Few differences in sensory profiles measured using quantitative sensory testing (QST) were found. Heat pain thresholds were normalized, possibly suggesting that the neuropathic group retained C-fiber and transient potential vanilloid 1 (TRPV1) function. Participants with neuropathic pain demonstrated significant differences with increased pain and decreased function.

Incidence and Risk Factors for Peripheral Nerve Injury After 383,000 Total Knee Arthroplasties Using a New York State Database (SPARCS)

BACKGROUND

Peripheral nerve injury (PNI) is a devastating complication following total knee arthroplasty (TKA). The purpose of this study is to identify risk factors for PNI after TKA using a New York Statewide Planning and Research Cooperative System.

METHODS

The Statewide Planning and Research Cooperative System database was queried to identify patients who had undergone TKA from 1996 to 2014. Patient demographics, medical history, surgical details, hospital characteristics, and in-hospital complications were recorded. Cases in which a new unilateral PNI was identified were compiled, as were control cases. The characteristics of cases and controls underwent univariate testing and a multivariate logistic regression using Akaike information criterion model selection to identify risk factors for the development of PNI after TKA.

RESULTS

In total, 383,060 cases were identified and 0.12%, or 445/383,060, experienced a new PNI. Pre-existing spinal conditions (odds ratio [OR] 1.98, confidence interval [CI] 1.08-3.30) and valgus deformity (OR 4.19, CI 2.46-6.66) were strongly correlated with the development of PNI postoperatively individually, but together increased risk substantially (OR 17.28, CI 2.83-55.35). Younger age (<50 years), in-hospital complications, female gender, and bilateral surgery were all associated with postoperative PNI, as well.

CONCLUSION

Valgus deformity and previous spine disorder together greatly increased the risk of PNI after TKA. Younger age, female gender, and in-hospital postoperative complications all increased the risk of PNI, as well. This study quantifies the relative risk each of these factors impart in the development of PNI after TKA and can help healthcare providers and systems identify and counsel patients at higher risk of this serious complication.

Thoracic Outlet Syndrome: A Comprehensive Review of Pathophysiology, Diagnosis, and Treatment

Thoracic outlet syndrome, a group of diverse disorders, is a collection of symptoms in the shoulder and upper extremity area that results in pain, numbness, and tingling. Identification of thoracic outlet syndrome is complex and a thorough clinical examination in addition to appropriate clinical testing can aide in diagnosis. Practitioners must consider the pathology of thoracic outlet syndrome in their differential diagnosis for shoulder and upper extremity pain symptoms so that patients are directed appropriately to timely therapeutic interventions. Patients with a definitive etiology who have failed conservative management are ideal candidates for surgical correction. This manuscript will discuss thoracic outlet syndrome, occurrence, physical presentation, clinical implications, diagnosis, and management.

Erythromelalgia and Peripheral Nerve Block: A Case Report

A 79-year-old woman with primary erythromelalgia underwent a left reverse total shoulder arthroplasty with a left interscalene nerve block, a superficial cervical plexus block, and a general endotracheal anesthetic, with no residual neurological deficits. Herein, we discuss the classification and pathophysiology of erythromelalgia along with the anesthetic considerations of peripheral nerve blockade in patients with primary erythromelalgia.

Adductor canal block with a suture-method catheter - A parallel or perpendicular approach?

BACKGROUND

We performed a randomised blinded pilot study in 16 healthy volunteers to assess whether placing a suture-method catheter in the adductor canal is feasible with two different insertion techniques.

METHODS

Each volunteer had a suture-method catheter placed approximately halfway between the superior anterior iliac spine and base of the patella in both legs. Catheters were placed using a parallel technique in one leg and a perpendicular technique in the other leg, according to randomisation. 15 mL lidocaine 1% was injected in each catheter. Successful placement was defined as loss of cold sensation in the saphenous area 30 min after injection. Volunteers were sent home and returned the following day and another dose of lidocaine (15 mL, 1%) was injected through the catheters. Catheter displacement distance was assessed by ultrasound and cold sensation was assessed. In case of preserved cold sensation, we attempted to reposition the catheter with a subsequent injection of lidocaine and reassessment of cold sensation.

RESULTS

All primary placements were successful using the perpendicular approach (100%; 95% CI 81%-100%) whereas one placement failed using the parallel approach (94%; 95% CI 72%-99%). Three catheters placed using the perpendicular approach were displaced on day 2, compared to one catheter placed with the parallel approach. Displacement distance was highly variable. All catheters, except one, could be repositioned. Three volunteers reported transient sensory deficits lasting approximately 6-8 weeks.

CONCLUSION

The suture-method catheter can be placed in the adductor canal with high success rates for initial placement with both techniques.

Surgical interventions for the treatment of painful neuroma: a comparative meta-analysis

A consensus on the optimal treatment of painful neuromas does not exist. Our objective was to identify available data and to examine the role of surgical technique on outcomes following surgical management of painful neuromas. In accordance with the PRISMA guidelines, we performed a comprehensive literature search to identify studies measuring the efficacy of the surgical treatment of painful neuromas in the extremities (excluding Morton's neuroma and compression neuropathies). Surgical treatments were categorized as excision-only, excision and transposition, excision and cap, excision and repair, or neurolysis and coverage. Data on the proportion of patients with a meaningful reduction in pain were pooled and a random-effects meta-analysis was performed. The effects of confounding, study quality, and publication bias were examined with stratified, meta-regression, and bias analysis. Fifty-four articles met the inclusion criteria, many with multiple treatment groups. Outcomes reporting varied significantly and few studies controlled for confounding. Overall, surgical treatment of neuroma pain was effective in 77% of patients [95% confidence interval: 73-81]. No significant differences were seen between surgical techniques. Among studies with a mean pain duration greater than 24 months, or median number of operations greater than 2 prior to definitive neuroma pain surgery, excision and transposition or neurolysis and coverage were significantly more likely than other operative techniques to result in a meaningful reduction in pain (P < 0.05). Standardization in the reporting of surgical techniques, outcomes, and confounding factors is needed in future studies to enable providers to make comparisons across disparate techniques in the surgical treatment of neuroma pain.

Myogenic fibrosis of the flexor tendons after amphetamine drug abuse

Myogenic fibrosis of the flexor tendons in a 23-year-old patient was caused by intense drug abuse. He was presented in the clinic with spastic flexor tendon contracture of his right hand. The patient was treated by tendon elongation with a satisfactory result. The treatment of flexor tendon contracture in those cases is very difficult and needs to be done in a complex way.

Surgical peripheral nerve decompression for the treatment of painful diabetic neuropathy of the foot - A level 1 pragmatic randomized controlled trial

AIMS

To assess the efficacy of surgical decompression of lower extremity nerves for the treatment of painful diabetic peripheral sensorimotor polyneuropathy (DPN).

METHODS

People with painful diabetic neuropathy were randomized single-blind to a lower extremity decompression surgery (n = 12) or observation (n = 10) for 1 year.

RESULTS

Pain was the primary outcome assessed with 2 measures. The McGill pain visual analogue scores over time changed within the groups (p for time < 0.0001), and changed differently over time within the groups (p for group × time = 0.0138). The NeuroQoL pain sensitivity analysis significantly changed from baseline to 12 months comparing intervention to control (p = 0.0079), and the joint effect of group and time on pain scores was statistically significant (p for group × time = 0.0009). At the study end-point of 12 months, intervention group participants had over 3 times the odds of rating their pain as "better" compared to "unchanged" or "worse" in the control group (p = 0.0177).

CONCLUSIONS

Surgical decompression of lower limb nerves was an effective treatment for decreasing pain in patients with DPN and superimposed nerve compressions.

The Role of the Peripheral Nerve Surgeon in the Treatment of Pain

Pain is a frequent cause of physician visits. Many physicians find these patients challenging because they often have complicated histories, emotional comorbidities, confusing examinations, difficult problems to fix, and the possibility of factitious complaints for attention or narcotic pain medications. As a result, many patients are lumped into the category of chronic, centralized pain and relegated to pain management. However, recent literature suggests that surgical management of carefully diagnosed generators of pain can greatly reduce patients' pain and narcotic requirements. This article reviews recent literature on surgical management of pain and four specific sources of chronic pain amenable to surgical treatment: painful neuroma, nerve compression, myofascial/musculoskeletal pain, and complex regional pain syndrome type II.

Management of Root-Level Double Crush: Case Report with Technical Notes on Contralateral Interlaminar Foraminotomy with Full Endoscopic Uniportal Approach

BACKGROUND

Double crush of a nerve at the root level is not common. We describe here a double crush of the right L4 nerve with foramina to far lateral disk (ventral) and extraforaminal (dorsal) compression. The double crush was managed by endoscopy with a contralateral uniportal approach from the left interlaminar space. Right lateral recess stenosis at the same level was subsequently managed with the same approach.

CASE DESCRIPTION

A 79-year-old lady presented to our clinic with a low backache, right leg pain, and weakness. On her right side, the straight leg raise test was 70 degrees, great toe dorsiflexion was grade 3/5, and hypoesthesia was present in the L4 dermatome. Her preoperative visual analog scale score was 9. Magnetic resonance imaging showed right lateral recess stenosis and a double compression of L4 nerve root from the dorsal and ventral sides. A diagnosis of right lateral recess stenosis with double crush of the right L4 nerve root was made. The patient was managed with percutaneous endoscopic contralateral interlaminar foraminotomy from the left interlaminar approach. She got relief for the symptoms and her postoperative visual analog scale score was 2. Magnetic resonance imaging and computed tomography showed nerve root decompression and well-preserved facet joints.

CONCLUSIONS

We conclude that the management of double crush at the nerve root level with interlaminar contralateral approach endoscopy (percutaneous endoscopic contralateral interlaminar foraminotomy) can deal with the issue effectively with facet joint preservation and other benefits of the minimally invasive spine procedure.

Microneurosurgical treatment options in peripheral nerve compression syndromes after chemotherapy and radiation treatment

Chemotherapy-induced peripheral neuropathy and radiation-induced brachial plexopathy are extremely debilitating conditions which can occur after treatment of malignancy. Unfortunately, the diagnosis can be elusive, and this dilemma is further compounded by the lack of efficacious therapeutics to prevent the onset of neurotoxicity before initiating chemotherapy or radiation or to treat these sequelae after treatment. However, microsurgical nerve decompression can provide these patients with a viable option to treat this complication.

A meta-analysis of surgical decompression in the treatment of diabetic peripheral neuropathy

BACKGROUND

Over the last decade, surgical decompression procedures have been commonly used in the treatment of diabetic peripheral neuropathy (DPN). However, the effectiveness of them remains to be proved.

METHODS

A comprehensive literature search of databases including PubMed-Medline, Ovid-Embase, and Cochrane Library was performed to collect the related literatures. The Medical Subject Headings used were "diabetic neuropathy," "surgical decompression," and "outcomes." The methodological index for nonrandomized studies was adopted for assessing the studies included in this review. Analyses were performed with Review Manager (Version 5.3, The Nordic Cochrane Centre, the Cochrane Collaboration, Copenhagen, 2014).

RESULTS

A total of 12 literatures (including 8 prospective and 4 retrospective) encompassing 1825 patients with DPN were included in the final analysis. Only 1 literature was identified as a randomized-controlled trial. The remaining 11 literatures were observational studies; 7 of them were classified as upper-extremity nerve decompression group and 4 of them were classified as lower-extremity nerve decompression group. Meta-analysis shows that Boston questionnaire symptom severity and functional status of upper extremities, and distal motor latency and sensory conduction velocity of median nerve of DPN patients are significantly improved after carpal tunnel release. Besides, visual analog scale and 2-point discrimination are considered clinically and statistically significant in lower extremities after operation.

CONCLUSIONS

The findings from our review have shown the efficacy of surgical decompression procedures in relieving the neurologic symptoms and restoring the sensory deficits in DPN patients. As there are few high-quality randomized-controlled trials or well-designed prospective studies, more data are needed to elucidate the role of surgical procedures for DPN treatment in the future.

Revision surgery for leg length inequality after primary hip replacement

BACKGROUND

We discuss the surgical results of revision surgery for patients with refractory symptomatic leg length inequality (LLI) after primary hip replacement.

METHODS

This is a retrospective review of 21 patients who underwent revision for LLI after primary total hip replacement. All of them were referred to a tertiary clinic between 2006 and 2015. Leg length was measured, to the nearest mm, using Woolson's validated X-ray technique which references to centre of femoral rotation, the acetabular teardrop and the midpoint of the lesser trochanter. The post-operative clinical assessment using a modified D'Aubigne and Postel scoring system investigated the pain, function, and satisfaction after surgery.

RESULTS

The mean pre-revision LLI was 16.2 mm (8-30 mm). The mean post revision operation leg length inequality was 2.0 mm (12 mm short to 9 mm long). The mean post-operative D'Aubigne and Postel scores, achieved at a mean 12 months (6-30 months), were; pain 5.2 (3-6), function 4.6 (3-6) and satisfaction 4.4 (3-5). Following revision surgery 20 out of 21 (95%) patients were satisfied with the improvement in LLI.

CONCLUSION

Revision surgery for LLI, while it may not resolve all of the pain that the patient presents with, it is a successful treatment for patients who do not respond to conservative management of their LLI.

Safe Use of Epidural Analgesia in a Parturient With Spinocerebellar Ataxia: A Case Report

A 28-year-old, gravida 7, para 4 woman with medical history of sickle cell trait presented to labor and delivery at 39 weeks of gestation for rupture of membranes. The patient had a history of suspected spinocerebellar ataxia with incomplete workup before the current admission. The patient requested epidural analgesia for labor. Epidural was placed at L3-L4 interspace without any complications and the rest of the labor was uneventful. Magnetic resonance imaging of the brain was performed after the delivery and the diagnosis of spinocerebellar ataxia was confirmed. The patient's neurological status remained stable after the procedure.

Investigation of the Effect of Cervical Radiculopathy on Peripheral Nerves of the Upper Extremity With High-Resolution Ultrasonography

STUDY DESIGN

Prospective, cross-sectional observational study.

OBJECTIVE

We aimed to investigate the effects of chronic cervical radiculopathy (CR) on the cross-sectional area (CSA) values of the cervical nerve roots (CNRs), median, ulnar, and radial nerves with high-resolution ultrasonography.

SUMMARY OF BACKGROUND DATA

Symptomatic nerve roots are wider than asymptomatic nerve roots due to the presence of edema. Peripheral nerves have also been shown to develop edema, fibrosis, and changes distal to the affected nerve as a result of mechanical compression. In addition according to "double-crush syndrome" hypothesis, the peripheral nerves are more sensitive to pressure, and a proximal nerve lesion makes the distal segment of the nerve more susceptible to anatomic deterioration by causing interruption in the axoplasmic conduction due to compression.

METHODS

Forty patients with chronic CR were included to the study. Both affected CNRs and the contralateral nerve roots (control group) were evaluated with high-resolution ultrasonography. Ulnar and median nerve CSA measurements were performed at four measurement points and radial nerve measurements at a single measurement point.

RESULTS

CSA measurements were statistically significantly higher at the CNR of the affected side compared to the unaffected side. There was no statistically significant difference when affected and unaffected sides were compared in terms of measurements performed from median, ulnar, and radial nerves at all measurement points.

CONCLUSION

The results of the present study indicate that the changes in the CNR caused by CR do not have any effect on the peripheral nerves. We did not find any affection in peripheral nerve CSA that might have been suggestive of double-crush syndrome in CR.

LEVEL OF EVIDENCE

2.

Evidence for Increased Magnetic Resonance Imaging Signal Intensity and Morphological Changes in the Brachial Plexus and Median Nerves of Patients With Chronic Arm and Neck Pain Following Whiplash Injury

Background Whiplash following a motor vehicle accident can result in chronic neck and arm pain. Patients frequently present with cutaneous hypersensitivities and hypoesthesia, but without obvious clinical signs of nerve injury. T2-weighted magnetic resonance imaging (MRI) has previously been used to identify nerve pathology. Objectives To determine whether there are signs of peripheral nerve pathology on MRI in patients with chronic arm and neck pain following whiplash injury. Methods This cross-sectional study used T2-weighted MRI to examine the brachial plexus and median nerve in patients and age-matched, healthy control subjects. Clinical examination included tests of plexus and nerve trunk mechanical sensitivity. Results The T2 signal intensity was greater in the brachial plexus and median nerve at the wrist in the patient group (mean intensity ratio = 0.52 ± 0.13 and 2.09 ± 0.33, respectively) compared to the control group (mean intensity ratio = 0.45 ± 0.07 and 1.38 ± 0.31, respectively; P<.05). Changes in median nerve morphology were also observed, which included an enlargement (mean area: patient group, 8.05 ± 1.29 mm²; control group, 6.52 ± 1.08 mm²; P<.05) and flattening (mean aspect ratio: patient group, 2.46 ± 0.53; control group, 1.62 ± 0.30; P<.05) at the proximal carpal row. All patients demonstrated signs of nerve trunk mechanical sensitivity. Conclusion These findings suggest that patients with chronic whiplash may have inflammatory changes and/or mild neuropathy, which may contribute to symptoms. J Orthop Sports Phys Ther 2018;48(7):523-532. Epub 24 Apr 2018. doi:10.2519/jospt.2018.7875.

Clinical Features and Surgical Treatment of Superficial Peroneal Nerve Entrapment Neuropathy

Superficial peroneal nerve (S-PN) entrapment neuropathy (S-PNEN) is comparatively rare and may be an elusive clinical entity. There is yet no established surgical procedure to treat idiopathic S-PNEN. We report our surgical treatment and clinical outcomes. We surgically treated 5 patients (6 sites) with S-PNEN. The 2 men and 3 women ranged in age from 67 to 91 years; one patient presented with bilateral leg involvement. Mean post-operative follow-up was 25.3 months. We recorded their symptoms before- and at the latest follow-up visit after surgery using a Numerical Rating Scale and the Japan Orthopedic Association score to evaluate the affected area. We microsurgically decompressed the affected S-PN under local anesthesia without a proximal tourniquet. We made a linear skin incision along the S-PN and performed wide S-PN decompression from its insertion point at the peroneal tunnel to the peroneus longus muscle (PLM) to the point where the S-PN penetrated the deep fascia. One patient who had undergone decompression in the area of a Tinel-like sign at the initial surgery suffered symptom recurrence and required re-operation 4 months later. We performed additional extensive decompression to address several sites with a Tinel-like sign. All 5 operated patients reported symptom improvement. In patients with idiopathic S-PNEN, neurolysis under local anesthesia may be curative. Decompression involving only the Tinel area may not be sufficient and it may be necessary to include the area from the PLM to the peroneal nerve exit point along the S-PN.

Comparison of peripheral nerve blockade characteristics between non-diabetic patients and patients suffering from diabetic neuropathy: a prospective cohort study

Animal data have demonstrated increased block duration after local anaesthetic injections in diabetic rat models. Whether the same is true in humans is currently undefined. We, therefore, undertook this prospective cohort study to test the hypothesis that type-2 diabetic patients suffering from diabetic peripheral neuropathy would have increased block duration after ultrasound-guided popliteal sciatic nerve block when compared with patients without neuropathy. Thirty-three type-2 diabetic patients with neuropathy and 23 non-diabetic control patients, scheduled for fore-foot surgery, were included prospectively. All patients received an ultrasound-guided popliteal sciatic nerve block with a 30 ml 1:1 mixture of lidocaine 1% and bupivacaine 0.5%. The primary outcome was time to first opioid request after block procedure. Secondary outcomes included the time to onset of sensory blockade, and pain score at rest on postoperative day 1 (numeric rating scale 0-10). These outcomes were analysed using an accelerated failure time regression model. Patients in the diabetic peripheral neuropathy group had significantly prolonged median (IQR [range]) time to first opioid request (diabetic peripheral neuropathy group 1440 (IQR 1140-1440 [180-1440]) min vs. control group 710 (IQR 420-1200 [150-1440] min, p = 0.0004). Diabetic peripheral neuropathy patients had a time ratio of 1.57 (95%CI 1.10-2.23, p < 0.01), experienced a 59% shorter time to onset of sensory blockade (median time ratio 0.41 (95%CI 0.28-0.59), p < 0.0001) and had lower median (IQR [range]) pain scores at rest on postoperative day 1 (diabetic peripheral neuropathy group 0 (IQR 0-1 [0-5]) vs. control group 3 (IQR 0-5 [0-9]), p = 0.001). In conclusion, after an ultrasound-guided popliteal sciatic nerve block, patients with diabetic peripheral neuropathy demonstrated reduced time to onset of sensory blockade, with increased time to first opioid request when compared with patients without neuropathy.

Two-Point Discrimination Predicts Pain Relief after Lower Limb Nerve Decompression for Painful Diabetic Peripheral Neuropathy

BACKGROUND

Peripheral nerve decompression surgery has been reported to be effective for pain reduction in patients with painful diabetic peripheral neuropathy. The aim of this study was to characterize which patients may have more pain relief benefits in the lower limbs after nerve decompression surgery.

METHODS

A retrospective study was conducted. Pain levels were measured with the Numerical Rating Scale. Treatment effects were classified by either substantial relief (at least 50 percent reduction in Numerical Rating Scale score compared with preoperative Numerical Rating Scale score) or nonsubstantial relief (<50 percent reduction or worse in Numerical Rating Scale score) at 12 months based on established criteria. Sex, age, body mass index, duration of diabetes mellitus, duration of diabetic peripheral neuropathy pain, preoperative Numerical Rating Scale score, and two-point discrimination were evaluated using univariate and logistic regression analysis.

RESULTS

The mean preoperative Numerical Rating Scale score (8.65 ± 1.29) decreased significantly 6 days (3.56 ± 2.22; p < 0.01), 6 months (3.03 ± 2.11; p < 0.01), and 12 months (3.44 ± 2.36; p < 0.01) after surgery; 64.7 percent of patients had substantial pain relief at 12 months. According to univariate and logistic regression analysis, better two-point discrimination was associated with substantial pain relief (OR, 3.700; p = 0.046, logistic regression analysis).

CONCLUSIONS

Nerve decompression surgery was able to alleviate pain in patients with painful diabetic peripheral neuropathy. Two-point discrimination may be a predictive factor for the prognosis of painful diabetic peripheral neuropathy after nerve decompression surgery.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Outcome of surgery for nerve injury following total hip arthroplasty

PURPOSE

During hip replacement, nerves in the operative field can be injured accidently. Additional surgical procedures can help restore function and reduce pain if there has been no recovery.

METHODS

One-hundred sixty-two patients presented with nerve injuries, and 113 were candidates for surgical treatment. The author performed 91 procedures on the injured limb (80 patients; 11 had 2 procedures) consisting of shortening, sympathectomy, tendon transfer, neurolysis or nerve repair/graft and 30 spinal and three fibular-neck decompressions. A meaningful recovery was defined as an increase of >1 level in strength or a reduction of >2 points on the visual analogue (VAS) pain scale.

RESULTS

Of 21 shortening procedures, 15 improved; of 12 nerve repair/grafting procedures, four improved. No patient >55 years of age made a meaningful recovery from a nerve repair/graft. One obturator nerve was resected and did not improve, and two were buried in muscle and had less pain. Of seven sympathectomies, six had less dysesthetic pain. Of 28 nerves treated with neurolysis, 24 made a meaningful recovery, with 13 making a near complete recovery. Of three fibular decompressions, two recovered completely. Of 20 tendon transfers, 18 made a meaningful recovery. Of 30 spinal decompressions, 25 made a meaningful recovery. There were six (5.3%) surgical complications (2 worsening pain, 2 infections, 2 deformities from tendon transfer).

CONCLUSIONS

If a sciatic, femoral or obturator nerve injury due to hip replacement does not recover spontaneously, additional surgical procedures can be of benefit.

The Prevention and Recognition of Ulnar Nerve and Brachial Plexus Injuries

Perioperative peripheral nerve injury is a serious yet preventable perioperative complication. Since the inception of the American Association of Anesthesiologists Closed Claim Project, the incidence of peripheral nerve injury has remained constant with an overall reported prevalence rate of 15% to 16%. To date, the most frequent nerve injuries are ulnar nerve neuropathy and brachial plexus injury. This article will review the clinical presentation, pathophysiology, causative and risks factors, and preventive measures for the two most common nerve injuries. Knowledge of the anatomical structures and components of peripheral nerves prone to injuries during surgery can assist in defining precautionary actions in the perioperative setting. Positioning techniques in the operating room, early recognition of neuropathies, and use of a perioperative tool in the postoperative setting are keys to reduce significant clinical complications.

Pectoralis Minor Syndrome: Subclavicular Brachial Plexus Compression

The diagnosis of brachial plexus compression-either neurogenic thoracic outlet syndrome (NTOS) or neurogenic pectoralis minor syndrome (NPMS)-is based on old fashioned history and physical examination. Tests, such as scalene muscle and pectoralis minor muscle blocks are employed to confirm a diagnosis suspected on clinical findings. Electrodiagnostic studies can confirm a diagnosis of nerve compression, but cannot establish it. This is not a diagnosis of exclusion; the differential and associated diagnoses of upper extremity pain are always considered. Also discussed is conservative and surgical treatment options.

Association of myelinated primary afferents impairment with mechanical allodynia in diabetic peripheral neuropathy: an experimental study in rats

To investigate the mechanisms underlying the efficacy of surgical treatment for painful diabetic peripheral neuropathy. Rats were initially divided into 3 groups (I, control rats, II, streptozotocin-induced diabetic rats, III, streptozotocin-induced diabetic rats with latex tube encircling the sciatic nerve without compression). When mechanical allodynia (MA) became stable in the third week, one third of group III rats were sacrificed and the remainder were further divided into subgroups depending on whether the latex tube was removed. Except for some rats in group III, all rats were sacrificed in the fifth week. Morphometric analysis of nerve fibers was performed. Expression level of GABA_B receptor protein in spinal dorsal horn was determined. Changes of GABA_B receptor within areas of primary afferents central terminal were identified. Chronic nerve compression caused by the interaction of diabetic nerves swelling and the encircling latex tube increased the incidence of MA in diabetic rats, and nerve decompression could ameliorate MA. In diabetic rats with MA, demyelination of myelinated fibers was noted and reduction of GABA_B receptor was mainly detected in the area of myelinated afferent central terminals. MA in DPN should be partially attributed to compression impairment of myelinated afferents, supporting the rationale for surgical decompression.

Prioritized cervical or lumbar surgery for coexisting cervical and lumbar stenosis: Prognostic analysis of 222 case

BACKGROUND CONTEXT

Single-stage surgery is usually applied to improving the symptoms of coexisting cervical and lumbar stenosis. In most cases, patients' willingness, surgery affordability, surgical trauma, surgical complications and patients' tolerance to surgery all limit the application of single-stage surgery. For patients who cannot receive single-stage surgery, we hope that we can find out by weighing up merits and flaws of the two surgical sites in order to make decision of prioritize one of the two surgery, so as to bring more benefits to the patients.

OBJECTIVE

To confirm which one of prioritized cervical surgery and prioritized lumbar surgery has a better effect in alleviating the symptoms of patients with coexisting cervical and lumbar stenosis.

STUDY DESIGN

A retrospective analysis and a cohort study for 15 years.

PATIENT SAMPLE

The information of 222 patients who were diagnosed with coexisting cervical and lumbar stenosis over the past 15 years was collected, including 144 patients who underwent prioritized cervical surgery and 78 prioritized lumbar surgery, thereafter the changes in the patients' postoperative neurological functions were evaluated.

OUTCOME MEASURES

Primary outcome variables are the clinical diagnosis event and the event of surgical site positioning. Secondary variables are the event of postoperative function changes and the symptom improvement event.

METHODS

The information about 222 patients with coexisting cervical and lumbar stenosis who had a follow-up of more than 1 year during January 2000 and December 2014 was collected. The effects of prioritized staged cervical and lumbar surgeries on the prognosis for the above-mentioned patients were respectively evaluated via relevant evaluation indexes.

RESULTS

The follow-up time was 18-156 months (58.0 ± 36.5). The lumbar reoperation rate after prioritized cervical surgery was lower than the cervical reoperation rate after prioritized lumbar surgery (22.91% < 57.69%) (P < 0.01). The JOA score and Nurick grade significantly improved (P < 0.01) and the ODI score improved (P < 0.05) after prioritized cervical surgery. No obvious improvement in the JOA score and Nurick grade (P > 0.05) was shown but the ODI score markedly improved (P < 0.01) after prioritized lumbar surgery.

CONCLUSIONS

For patients with coexisting cervical and lumbar stenosis, prioritized cervical surgery is safe and effective and is superior to prioritized lumbar surgery on the improvement of cervical and lumbar symptoms, the postoperative recovery of limb function and the rate of reoperation on another site.

Double crush syndrome caused by cervical spondylosis and vertebral artery loop

PURPOSE

The purpose of this article is to report a successful treatment experience in a rare case of simultaneous cervical nerve root compression by spondylotic cervical foraminal stenosis and a vertebral artery loop.

METHODS

51-year-old man presented with a 4-year history of left-sided cervical pain radiating to the left shoulder with progressive exacerbation of weakness on left shoulder girdle muscles for 7 months. The patient had no history of trauma. The patient's CT and MRI revealed impingement of the left C6 cervical nerve root by a tortuous vertebral artery loop and also by narrowed left C5-6 cervical foramen that had undergone spondylotic changes. The patient underwent left C5-6 hemilaminectomy, facetectomy and C5-6 fusion. The procedures were uneventful, and the patient recovered with complete resolution of symptoms.

RESULTS

The patient continued to be asymptomatic at a 2-year follow-up examination, and the muscle mass of his left girdle returned normal.

CONCLUSIONS

This report illustrates the first phenomenon of a double crush syndrome caused by vertebral artery loop and cervical spondylotic changes. When patients with cervical spondylosis present with unexplainably severe pain and weakness, additional underlying pathologies should be considered when making differential diagnoses. The investigation planning should involve electromyography, computed tomography angiography, and magnetic resonance imaging.

Effects of decompression on behavioral, electrophysiologic, and histomorphologic recovery in a chronic sciatic nerve compression model of streptozotocin-induced diabetic rats

Purpose

To determine susceptibility to decompression surgery in diabetic and nondiabetic peripheral neuropathy using a chronic compression neuropathy model.

Materials and methods

Twenty-four streptozotocin-induced diabetic rats were randomly divided into three groups: group I, chronic compression of the left sciatic nerve for 4 weeks with decompression; group II, similar without decompression; and group III, sham exposing the sciatic nerve only. The other 24 nondiabetic rats were assigned to groups IV–VI, which received compression–decompression, compression, and the sham operation, respectively. Mixed-nerve-elicited somatosensory evoked potentials (M-SSEPs) and compound muscle action potentials (CMAPs) were measured to verify the compression neuropathy in the posttreatment follow-up. Behavioral observations in thermal hyperalgesia tests were quantified before electrophysiologic examinations. Treated and contralateral nerves were harvested for histomorphologic analysis.

Results

Chronic compression of sciatic nerve induced significant reduction of amplitude and increment of latency of M-SSEP and CMAP in both diabetic and nondiabetic rats. Diabetic group changes were more susceptible. Decompression surgery significantly improved both sensory and motor conduction, thermal hyperalgesia, and the mean myelin diameter of the rat sciatic nerve in both diabetic and nondiabetic groups. Near full recovery of motor and sensory function occurred in the nondiabetic rats, but not in the diabetic rats 8 weeks postdecompression.

Conclusion

Behavioral, electrophysiologic, and histomorphologic findings indicate that decompression surgery is effective in both diabetic and nondiabetic peripheral neuropathy.

[Posttraumatic nerve entrapment syndromes in the upper extremities]

Nerve entrapment syndromes in the upper extremities are common clinical disease patterns, less often as direct results of accidents. The most frequent compression syndrome is the carpal tunnel syndrome followed by the cubital tunnel syndrome. If the cause of the compression cannot be eliminated by conservative treatment options, an operative therapy is necessary. As the prognosis becomes worse with the duration of the nerve compression, it is important to initiate therapy at an early stage.

Musculoaponeurotic Variations along the Course of the Median Nerve in the Proximal Forearm

31 cadaver arms have been dissected to study the variations in the anatomy of the muscles and fibrous arches which might cause compression of the median nerve in the forearm. Pronator teres always had a superficial head and usually a deep head. Flexor digitorum superficialis varied greatly in its site of origin.

The median nerve might be crossed by two, one or no fibro-aponeurotic arches. Gantzer’s muscle, an accessory head of flexor pollicis longus, was present in 45% of cadavers. No ligament of Struthers was found. Possible sites and causes of nerve compression are discussed.