Current concepts of carpal tunnel syndrome: pathophysiology, treatment, and evaluation

Ultrasound-guided needle release of the transverse carpal ligament with and without corticosteroid injection for the treatment of carpal tunnel syndrome

BACKGROUND

To compare the clinical effectiveness of ultrasound-guided needle release of the transverse carpal ligament (TCL) with and without corticosteroid injection in carpal tunnel syndrome (CTS).

METHODS

From June 2016 to June 2017, 49 CTS patients (50 wrists) were included in this study. Twenty-five wrists were treated with ultrasound-guided needle release of the TCL plus corticosteroid injection (group A), and 25 wrists were treated with single ultrasound-guided needle release of the TCL (group B). The following parameters were assessed and compared including postprocedure results according to relief of symptoms, ultrasound parameters (cross-sectional area of the median nerve at the levels of pisiform, flattening ratio of median nerve at the levels of the hamate bone, and the thicknesses of TCL on the cross-section at the level of the hamate bone), and electrophysiological parameters (distal motor latency and sensory conduction velocity).

RESULTS

Group A had higher overall excellent and good rate 3 months after the procedure than group B (84 vs 52%, P < 0.05). There were significant differences regarding the above ultrasonic and electrophysiological parameters between the baseline and postprocedure values in both groups (all P < 0.05). There were significant differences regarding the postprocedure values of above ultrasonic and electrophysiological parameters between the two groups (all P < 0.05). No complications such as infection or tendon rupture were noted. No procedures were converted to the open release.

CONCLUSIONS

Both techniques are effective in treating CTS. Ultrasound-guided needle release of the TCL with corticosteroid injection had better treatment benefits than single ultrasound-guided needle release of the TCL in treating CTS.

Predictive Variables for Sonographically Guided Corticosteroid Injection in Mild-to-Moderate Carpal Tunnel Syndrome

OBJECTIVE

To assess the predictive variables after sonographically guided corticosteroid injection in carpal tunnel syndrome.

METHODS

A prospective, observational study was carried out on 25 wrists of 20 consecutive patients with carpal tunnel syndrome, confirmed by the American Association of Neuromuscular and Electrodiagnostic Medicine criteria, which includes clinical history, symptoms, and evidence of slowing of distal median nerve conduction. Visual analogue scale (VAS) and Boston Carpal Tunnel Questionnaire (BCTQ) were asked to the patients before and 4 weeks after the procedure. On a basis of VAS difference before and after the procedure, we divided the patients into two groups: more than 50% of VAS improving (good response group) and less than 50% of VAS improving (poor response group). Also, nerve conduction studies and ultrasound evaluations were performed prior to sonographically guided corticosteroid injection and at 4 weeks after the procedure. The cross-sectional area (CSA) of median nerve at maximal swelling point around wrist was measured by manual tracing using ultrasonography. With assessments mentioned above, we tried to assess predictive variables for prognosis after sonographically guided corticosteroid injection in carpal tunnel syndrome.

RESULTS

The CSA of median nerve at wrist measured before the procedure was significantly larger in good response group than in poor response group. Furthermore, the CSA of median nerve at wrist, symptom severity scale of BCTQ, motor/sensory latency and sensory amplitude were correlated with VAS improving.

CONCLUSION

The CSA of median nerve at wrist is the strongest predictive value for sonographically guided corticosteroid injection in mild-to-moderate carpal tunnel syndrome.

Hypercholesterolemia Is Associated with the Subjective Evaluation of Postoperative Outcomes in Patients with Idiopathic Carpal Tunnel Syndrome Who Undergo Surgery: A Multivariate Analysis

BACKGROUND

Carpal tunnel syndrome is a compression neuropathy of the median nerve at the wrist; its symptoms include neuropathic pain and sensory and motor disturbance distributed by the median nerve. Carpal tunnel syndrome and hypercholesterolemia have similar backgrounds, but the effect of these similarities on postoperative outcomes has not been reported. Using multivariate analysis, the authors analyzed the relationship between prognostic factors, including the presence of hypercholesterolemia, and subjective postoperative outcomes of patients with idiopathic carpal tunnel syndrome.

METHODS

Of 168 hands with carpal tunnel syndrome that were treated surgically, 141 that were followed up and assessed 1 year postoperatively or thereafter were included. The mean postoperative follow-up period was 40.8 months. Surgery was performed through a small palmar skin incision under local anesthesia. The outcomes were postoperative symptoms, including pain and numbness, and overall Kelly assessment.

RESULTS

Preoperative numbness and pain resolved and alleviated in 94 of 141 hands and was diminished in 59 of 64 hands. Univariate analysis showed that postoperative numbness and Kelly assessment were significantly associated with hypercholesterolemia. Multivariate analysis showed that postoperative numbness was significantly associated with smoking and hypercholesterolemia, and Kelly assessment was significantly associated with smoking (adjusted OR, 3.3; 95 percent CI, 1.1 to 10; p = 0.04) and hypercholesterolemia (adjusted OR, 2.9; 95 percent CI, 1.4 to 6.3; p = 0.01).

CONCLUSION

Hypercholesterolemia, usually a systemic condition in sites other than the hand, is associated with the subjective evaluation of postoperative symptoms in patients with idiopathic carpal tunnel syndrome.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Is there a relationship between impaired median nerve excursion and carpal tunnel syndrome? A systematic review

STUDY DESIGN

Systematic review.

INTRODUCTION

It is accepted that the etiology of carpal tunnel syndrome (CTS) is multifactorial. One of the most commonly accepted etiologic factors for CTS is compromise of the kinematic behavior and excursion of the median nerve.

PURPOSE OF THE STUDY

The objective of this systematic review was to establish if there is a relationship between impaired median nerve excursion and CTS.

METHODS

A systematic review, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, was conducted. Studies were sought where in vivo median nerve excursion was compared between people with CTS to an appropriate control group. Quality appraisal for each study was conducted using the Newcastle-Ottawa Scale by 2 independent evaluators.

RESULTS

Ten case-control studies using ultrasound imaging to quantify median nerve excursion were included. All studies were rated as of "moderate" methodologic quality having scored 6 or 7 (of 9 stars) for the Newcastle-Ottawa Scale. Seven of the 10 studies concluded that median nerve excursion was reduced in a CTS population when compared with controls.

CONCLUSION

The literature suggests that median nerve excursion is reduced in people with CTS when compared with healthy controls.

LEVEL OF EVIDENCE

3a.

Mechanical wrist traction as a non-invasive treatment for carpal tunnel syndrome: a randomized controlled trial

BACKGROUND

Carpal tunnel syndrome (CTS) is a common, compressive nerve-entrapment disorder with symptoms of numbness, paresthesia, and pain. Carpal tunnel release surgery is the only known long-term effective treatment. However, surgery is invasive and up to 30% of patients report recurrence or persistence of symptoms or suffer from post-surgical complications. A promising non-surgical treatment for CTS is mechanical wrist traction. The purpose of this study was to evaluate clinical outcomes following mechanical traction in patients with CTS compared to care as usual.

METHODS

Adult patients (N = 181, mean age 58.1 (13.0) years, 67% women) with electrodiagnostically confirmed CTS were recruited from an outpatient neurology clinic in the Netherlands between October 2013 and April 2015. After baseline assessments, patients were randomized to either the intervention group (12 treatments with mechanical traction, twice a week for a period of 6 weeks) or "care as usual". The main clinical outcome measure was surgery during 6 months' follow-up. In addition, symptom severity was measured using the Boston Carpal Tunnel Questionnaire (BCTQ) at baseline, 3, and 6 months' follow-up. Baseline characteristics and severity of CTS symptoms at follow-up were compared between the intervention and care-as-usual groups using a t test and χ 2 tests. Time to event (surgery) between the groups was analyzed using Kaplan-Meier survival analysis and Cox proportional hazards analysis.

RESULTS

The intervention group had fewer surgeries (28%) compared to the care-as-usual group (43%) during follow-up (χ21 = 4.40, p = .036). Analyses of the survival curves revealed a statistically significant difference between the groups over time (log-rank test χ 21 = 6.94, p = .008). At 6 months' follow-up, symptom severity and functional status scores had significantly decreased from baseline in both groups (p < .001) and the improvements did not differ between the two groups.

CONCLUSIONS

Mechanical traction is associated with fewer surgical interventions compared to care as usual in CTS patients. Reductions in patient-reported symptoms at 6 months' follow-up was similar in both groups. The long-term effects of mechanical traction require further evaluation.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NL44692.008.13 . Registered on 19 September 2013.

Semivertical Incision: An Aesthetically and Electrophysiologically Effective Mini-Incision Technique for Carpal Tunnel Decompression

Background

The purpose of this study was to present the clinical results of our retrospective series of carpal tunnel release (CTR) operations. For these operations we used a unique type of incision, for the first time, for treatment of carpal tunnel syndrome (CTS) consisting of a 1-cm semi-vertical (SV) incision made into the wrist crease for macroscopic open CTR.

Material/Methods

This retrospective study included 114 patients (101 females and 13 males) with CTR who were operated upon in our neurosurgery clinic between December 2010 and June 2015. Patient ages ranged from 35 to 83 years (mean 55.05±12.04 years). In total, 127 hands (73 right and 54 left) were operated upon using the SV skin incision technique. After an average follow-up of 18 months (ranging from 6 to 30 months), clinical and electrophysiological (EP) evaluations were performed.

Results

A review of the English language literature published since 1957, when Phalen first popularised the diagnosis and treatment of this disease, determined that no previous reports of the mini-open incision technique as described in our study have been published. In our retrospective patient case review, we found that after operations using the SV incision technique, statistically significant differences were detected in electromyography (EMG) improvements (p<0.01). In addition, patients who showed improvement in EMG studies (n=90) were satisfied with the result of their surgery.

Conclusions

Our study demonstrated that 1-cm skin SV incision was a cosmetically satisfying, fast, and safe approach to CTR that was not only clinically effective but also electrophysiologically effective.

Comparison of the Clinical Effectiveness of Ultrasound-Guided Corticosteroid Injection with and without Needle Release of the Transverse Carpal Ligament in Carpal Tunnel Syndrome

BACKGROUND

To compare the clinical effectiveness of ultrasound-guided corticosteroid injection with and without needle release of the transverse carpal ligament (TCL) in carpal tunnel syndrome (CTS).

METHODS

Between May 2014 and June 2016, 52 patients (56 wrists) with CTS were included in this study. Among these patients, 28 wrists were treated with ultrasound-guided corticosteroid injection plus needle release of the TCL (group A) and 28 wrists were treated with a single ultrasound-guided corticosteroids injection (group B). The following parameters were assessed and compared including postoperative results of procedure based on relief of symptoms, electrophysiological parameters (distal motor latency, sensory conduction velocity, and sensory nerve action potential of median nerve), and ultrasound parameters (anteroposterior diameter and cross-sectional area of the median nerve at the levels of pisiform and hamate bone, and the thicknesses of TCL on the cross-section at the level of hamate bone).

RESULTS

The overall excellent and good rate regarding the postoperative results of procedure based on the relief of symptoms at 1 month postoperatively was 82.1% in group A and 46.4% in group B (p = 0.004). There was significant difference in the above electrophysiological and ultrasound parameters between the preoperative and postoperative values in both groups (all p < 0.05). Furthermore, a significant difference was also observed in the postoperative values of the above-mentioned electrophysiological and ultrasound parameters in the 2 groups (all p < 0.05).

CONCLUSIONS

Both approaches had treatment benefit in CTS. Ultrasound-guided corticosteroid injection in combination with needle release of the TCL is superior to the single ultrasound-guided corticosteroids injection.

Can flexor tenosynovectomy and microsurgical epineurectomy improve clinical outcomes following open carpal tunnel release?

INTRODUCTION

The purpose of this study was to comparatively evaluate the clinical outcomes of open carpal tunnel release with or without flexor tenosynovectomy and epineurectomy for the treatment of idiopathic carpal tunnel syndrome.

METHODS

In this prospective single-blinded study, 61 wrists of 47 patients randomized to open carpal tunnel release without (Group-1) or with (Group-2) flexor tenosynovectomy and microsurgical epineurectomy. Physical examination including Phalen and Tinel's signs, visible thenar atrophy, two-point discrimination, and grip strength measurement was performed. Visual Analogue Scale (VAS), Quick Disability of Arm Shoulder Hand (DASH) Questionnaire, Symptoms Severity Scale, Functional Status Scale, and electrophysiological study were assessed.

RESULTS

The increase in the grip strength and Quick Disability of Arm Shoulder Hand Questionnaire score were significantly better in flexor tenosynovectomy and microsurgical epineurectomy group. The average pre-operative two-point discrimination was 6.3 ± 2 mm in Group-1 and 5.8 ± 1.7 mm in Group-2. Post-operatively at the end of 12 months, the mean two-point discrimination was measured as 5.9 ± 1.6 mm in Group-1 and 5.6 ± 1.3 mm in Group-2. When we compare the two groups according to the changes in VAS, Quick-DASH, symptoms severity scale, and functional status scale, only Quick-DASH score improvement was significantly better in Group-2 (p < 0.05). Improvements in VAS, symptoms severity scale, and functional status scale did not differ significantly.

CONCLUSION

We do not recommend routine flexor tenosynovectomy and microsurgical epineurectomy during open carpal tunnel release in patients with idiopathic carpal tunnel syndrome.

Diagnosing carpal tunnel syndrome with Doppler ultrasonography: a comparison of ultrasonographic measurements and electrophysiological severity

INTRODUCTION

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Diagnosis is based on clinical history, physical examination, and electrophysiological studies. Imaging techniques are performed for difficult-to-diagnose cases because they provide information about the morphology of the median nerve. More recently, it has been shown that Doppler ultrasonography can detect increased intraneural blood flow in CTS. The aim of our study is to evaluate the relationship between the severity of CTS, hypervascularization, and cross-sectional area (CSA) to determine the diagnostic value of Doppler ultrasonography.

PATIENTS AND METHODS

The study group comprised 125 wrists of 75 patients who had been diagnosed with CTS, both clinically and electrophysiologically. The control group comprised 100 wrists of 50 healthy volunteers. Wrists were classified into five stages of CTS severity based on electrophysiologic studies. A radiologist examined the wrists blindly with grayscale images and Doppler ultrasonography to assess CSA and hypervascularization.

RESULTS

A total of 121 wrists were included. There were 28 wrists with minimal CTS severity stage, 36 with mild, 36 with moderate, and 21 with severe. The sensitivity and specificity of CSA and hypervascularization in detecting CTS was 90.9, 94.0, 93.4, and 90.0%, respectively. There was a significant correlation between CTS severity and hypervascularization (p < 0.005) for all stages.

CONCLUSION

Our study shows that Doppler ultrasonography results strongly correlate with CTS severity. Hence, this is a useful method for diagnosing CTS and estimating its severity.

A Topical Gel From Flax Seed Oil Compared With Hand Splint in Carpal Tunnel Syndrome: A Randomized Clinical Trial

This study compared the therapeutic effect of flax seed oil topical gel and hand splint in the treatment of carpal tunnel syndrome. This study was a randomized clinical trial. Forty-nine patients, 96 hands, with mild to moderate idiopathic carpal tunnel syndrome were divided into 2 groups randomly. One group was treated by topical gel and the other group by hand splint. Intensity of symptoms and function before and after intervention was measured via Boston Carpal Tunnel Questionnaire. After intervention, the ANCOVA showed a significant difference between the symptom and function scores of the 2 groups. In both cases, recovery was higher in the gel group (P < .001). The topical use of flax seed oil gel is more effective in the improvement of symptoms and function of patients with mild to moderate carpal tunnel syndrome as compared with hand splint, and it can be introduced as an effective treatment.

Assessing the Reliability of Ultrasound Imaging to Examine Radial Nerve Excursion

Ultrasound imaging allows cost effective in vivo analysis for quantifying peripheral nerve excursion. This study used ultrasound imaging to quantify longitudinal radial nerve excursion during various active and passive wrist movements in healthy participants. Frame-by-frame cross-correlation software allowed calculation of nerve excursion from video sequences. The reliability of ultrasound measurement of longitudinal radial nerve excursion was moderate to high (intraclass correlation coefficient range = 0.63-0.86, standard error of measurement 0.19-0.48). Radial nerve excursion ranged from 0.41 to 4.03 mm induced by wrist flexion and 0.28 to 2.91 mm induced by wrist ulnar deviation. No significant difference was seen in radial nerve excursion during either wrist movement (p > 0.05). Wrist movements performed in forearm supination produced larger overall nerve excursion (1.41 ± 0.32 mm) compared with those performed in forearm pronation (1.06 ± 0.31 mm) (p < 0.01). Real-time ultrasound is a reliable, cost-effective, in vivo method for analysis of radial nerve excursion.

Carpal Tunnel Syndrome in Obstructive Sleep Apnea Patients

Introduction

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper extremity. It is usually associated with the compression of the median nerve in the median groove. Because the main symptoms of CTS pain and numbness worsen at night, sleep disorders in CTS patients and the impact of preferred sleeping position on CTS development have been formerly studied. However, to the best of our knowledge, this is the first study assessing the frequency of CTS in obstructive sleep apnea (OSA) patients. This study aimed to determine the frequency of CTS in OSA patients and evaluate the causative relation between the two diseases.

Methods

Records of individuals who were admitted to our sleep laboratory were retrospectively scanned. Eighty patients who were diagnosed with OSA and did not have comorbidities that might cause OSA (e.g., diabetes mellitus, hypothyroiditis, rheumatic diseases, and cervical radiculopathy) were included in the study along with 80 healthy controls who matched for age, sex, and BMI of OSA patients. To maintain observer blindness, patients were not questioned regarding their symptoms or the clinical data that would be used in the study. All participants underwent nerve conduction studies. Those who were diagnosed with CTS were questioned regarding CTS symptoms and the preferred sleeping position. Subsequently, patients were given the Boston CTS questionnaire.

Results

CTS frequency in OSA patients was found to be 27.5%. There was no significant relation between preferred sleeping position or being a manual worker and having CTS.

Conclusion

CTS frequency in OSA patients is significantly higher than that in healthy individuals. In contrast to previous studies that have been performed in the absence of polysomnographic and electrophysiological data, in our study biomechanical factors were not associated with CTS presence. Therefore, we conclude that intermittent hypoxemia is the main etiological factor for CTS in OSA patients. Inflammation may be a common factor for etiopathogenesis for both diseases, but this hypothesis needs further investigation.

Determination of the longitudinal median nerve mobility in different neurodynamic techniques

Background

Neurodynamic techniques which include tensioning and gliding techniques are being employed in the treatment of carpal tunnel syndrome. There are few in vivo studies that have assessed the longitudinal mobility of the nerve using these techniques. The objective of this study was to determine the longitudinal excursion of the median nerve at the level of the wrist and distal arm by having the cervical spine lateral flexion or the wrist extension as terminal movement.

Method

Twenty healthy participants were included in the study. Techniques 1 and 2 had wrist extension as its terminal movement while techniques 3 and 4 had ipsilateral and contralateral neck lateral flexion as its terminal motion. Median nerve longitudinal excursion was determined using dynamic ultrasound and was measured by a motion tracking analysis program employing a fast template tracking method.

Results

Regardless of neurodynamic techniques, longitudinal mobility is highest at the wrist and arm level if the terminal movement is wrist extension. Median nerve excursion at the wrist and arm levels is 15.53 ± 7.04 mm and 6.82 ± 2.97 mm for technique 1 and 13.43 ± 5.64 and 5.33 ± 2.37 mm for technique 2, respectively. There was a significant decrease in median nerve excursion at the wrist level when the terminal movement was at the cervical spine.

Conclusion

The largest median nerve excursion in the arm and wrist occurred when wrist extension is the terminal movement. Contralateral cervical lateral flexion with a prepositioned extended wrist produced the least motion of the median nerve at both sites.

Carpal Tunnel Syndrome in Behçet's Disease

PURPOSE

Behçet's disease (BD) is a chronic inflammatory disease characterized by orogenital ulcers, skin and ocular lesions, in addition to articular, vascular, and neurologic symptoms. Carpal tunnel syndrome (CTS), can also occur in BD patients secondary to inflammation in the connective tissues, vessels, and tendons, as well as nerve involvement in BD itself. However, reports of patients who have CTS in BD are rare. The aim of this study was to evaluate the clinical characteristics of CTS in BD patients.

MATERIALS AND METHODS

Retrospective analysis of the medical records of 1750 BD patients, and 14 (0.8%) BD patients who were diagnosed with CTS was performed at the BD Specialty Clinic of Severance Hospital. Patient demographics, disease activity/severity for both diseases, and the clinical characteristics of CTS in BD were recorded and analyzed.

RESULTS

All 14 BD patients with CTS were women. Twelve patients (85.7%) were diagnosed with active BD. The CTS was mild in 8 patients (57.2%), moderate in 3 patients (21.4%), and severe in 3 patients (21.4%). Ten patients (71.4%) had BD prior to the diagnosis of CTS, and these 10 patients all had active BD.

CONCLUSION

CTS can occur as a result of the inflammation associated with BD and can also be the presenting symptom of nerve involvement in BD. CTS can also develop as the initial symptom of BD. Therefore, a higher degree of suspicion should be maintained for CTS in patients with BD and vice versa; however, the exact relationship is uncertain.

Carpal tunnel syndrome and prediabetes: is there a true association?

BACKGROUND

Carpal tunnel syndrome (CTS) is probably associated with diabetes mellitus, but its link to prediabetes (PD) is unknown.

OBJECTIVE

To determine prevalence of PD and others risk factors in CTS.

METHODS

A cross-sectional study including 115 idiopathic CTS patients and 115 age-, gender-and body mass index (BMI)-matched controls was performed. Clinical, laboratory and neurophysiological evaluations were conducted in all subjects to confirm CTS diagnosis. CTS severity was graded on a standardized neurophysiological scale. PD was defined using strict criteria.

RESULTS

The prevalence of PD was similar in CTS and control groups (27% vs. 21.7%, respectively P=0.44). Nocturnal symptoms (91.3%) and moderate CTS (58.3%) were most frequently observed in CTS patients. In logistic regression analysis, PD was significantly correlated with age (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.01-1.09; P=0.006) and BMI (OR 1.08. 95% CI 1.01-1.16; P=0.026), but not with CTS (OR 0.82, 95% CI 0.43-1.53; P=0.537). CTS patients with PD had a significantly higher mean age compared to those without PD (53.8±10.2 vs. 49.5±8.6 years, respectively P=0.027). The frequency of age >60 years was significantly higher in CTS with PD than in CTS without PD (29.0% vs. 8.3%, respectively P=0.04) as was BMI >30kg/m(2) (64.5% vs. 33.3%, respectively P=0.03). No significant differences were observed between the two CTS groups with respect to gender, BMI, symptoms, and neurophysiological severity of CTS.

CONCLUSIONS

Our findings indicated that CTS is not associated with PD, but that PD is closely linked to age and overweight.

Comparison of the histopathological findings of patients with diabetic and idiopathic carpal tunnel syndrome

PURPOSE

This study is aimed to investigate whether there are any histopathological differences between diabetic and idiopathic carpal tunnel syndromes.

METHODS

The biopsy specimens were taken from transverse carpal ligament (TCL), tenosynovium adjacent to median nerve and epineurium of median nerve and evaluated in 47 patients (21 diabetic and 26 idiopathic) who were diagnosed with carpal tunnel syndrome (CTS) and treated surgically with open carpal tunnel release. Fibroblast proliferation, fibrosis, perivascular inflammation, oedema, vascular proliferation and vascular wall thickness were determined and scored in all specimens.

RESULTS

There weren't any histopathological abnormalities in TCL specimens of both groups. Synovial hyperplasia, fibrosis and perivascular inflammation were not observed in tenosynovial analysis of both groups. Diabetic CTS patients, when compared with idiopathic CTS patients, had higher rates of synovial edema (idiopathic CTS 57 %, diabetic CTS 87 %), vascular proliferation (idiopathic CTS 30.8 %, diabetic CTS 90.5 %) and increased vascular wall thickness (idiopathic CTS 11.5 %, diabetic CTS 90.5 %). There was no oedema, fibrosis and perivascular inflammation of the epineurium in specimens of either group. But increases in vascular proliferation (idiopathic CTS 7.7 %, diabetic CTS 71.4 %) and vascular wall thickness (idiopathic CTS 3.8 %, diabetic CTS 71.4 %) was seen in the epineurium of diabetic patients and these differences were statistically significant (p < 0.05).

CONCLUSION

Because of the severe synovial and epineurial histopathological abnormalities and inadequate neural regeneration capacity, surgical open carpal tunnel decompression should be planned earlier in diabetic CTS patients. Further studies should be considered to evaluate the histopathological features of diabetic CTS patients early in the course of the disease.

A non-scalpel technique for minimally invasive surgery: percutaneously looped thread transection of the transverse carpal ligament

PURPOSE

This study aims to develop an alternate technique for improving the surgical procedure of carpal tunnel release.

METHOD

The transverse carpal ligament is transected by utilizing a piece of thread looped percutaneously under the visualization of ultrasound. The procedure, the thread carpal tunnel release (TCTR), was performed on 34 hands of 20 patients. Self-administrated Levine-Katz questionnaire was used for assessing the symptom severity and functional status of the outcomes.

RESULTS

TCTR was performed in each case with no unintended consequences. The average duration for a procedure was 7 min, excluding time of preparation. Significant improvements in subjective sensibility were reported within 24 h, and sleep quality improved for all cases. There were no postoperative complications. The scores of questionnaire 3 months postoperatively were comparable to the literature controls.

CONCLUSION

TCTR is a safe and effective minimally invasive surgery performed under local anesthesia in a clinic-based procedure room and results in only one-needle entrance point at the wrist and one-needle exit point in the palm. The feature of the procedure includes the potentials of reduced risk of iatrogenic injury, reduced surgical cost, and reduced patient recovery time. The study has shown encouraging promise for optimizing the technique of carpal tunnel release, and more clinical trials are necessary to confirm the findings.

Effect of wrist angle on median nerve appearance at the proximal carpal tunnel

This study investigated the effects of wrist angle, sex, and handedness on the changes in the median nerve cross-sectional area (MNCSA) and median nerve diameters, namely longitudinal diameter (D1) and vertical diameter (D2). Ultrasound examination was conducted to examine the median nerve at the proximal carpal tunnel in both dominant and nondominant hands of men (n = 27) and women (n = 26). A total of seven wrist angles were examined: neutral; 15°, 30°, and 45° extension; and 15°, 30°, and 45° flexion. Our results indicated sexual dimorphism and bilateral asymmetry of MNCSA, D1 and D2 measurements. MNCSA was significantly reduced when the wrist angle changed from neutral to flexion or extension positions. At flexion positions, D1 was significantly smaller than that at neutral. In contrast, at extension positions, D2 was significantly smaller than that at neutral. In conclusion, this study showed that MNCSA decreased as the wrist angle changed from neutral to flexion or extension positions in both dominant and nondominant hands of both sexes, whereas deformation of the median nerve differed between wrist flexion and extension.

Biphasic motion of the median nerve in the normal Asian population

BACKGROUND

The biomechanical interaction between the median nerve and the flexor tendons is an important consideration in Carpal tunnel syndrome (CTS). We aim to quantify the displacement and compressive deformation pattern of the median nerve in various stages of finger flexion in the normal population at the inlet of the carpal tunnel.

METHODS

Transverse ultrasounds images were taken at the carpal tunnel inlet during full-extension, mid-flexion and full flexion. The displacement, distance, Feret's diameter, and perimeter of the median nerve were calculated and compared between each position.

RESULTS

Biphasic median nerve motion was observed, with a displacement of 2.84 ± 3.49 mm in the ulnar direction from full-extension to mid-flexion (Phase I) and a further 0.93 ± 3.04 mm from mid-flexion to full flexion (Phase II). Of 49 hands, 37 (75.5%) exhibited ulnar displacement in Phase I while 12 (24.5%) exhibited radial displacement. Feret's diameter (5.95 ± 1.08 mm) and perimeter (13.28 ± 2.09) of the median nerve were greatest in the mid-flexed position.

CONCLUSION

In a healthy Asian population, the median nerve has a biphasic motion during finger flexion, with maximal deformation in the mid-flexed position.

Effect of synovial transthyretin amyloid deposition on preoperative symptoms and postoperative recovery of median nerve function among patients with idiopathic carpal tunnel syndrome

BACKGROUND

The clinical characteristics of wild-type transthyretin amyloid deposition among patients with carpal tunnel syndrome (CTS) have not been well investigated.

METHODS

One-hundred and seven patients with idiopathic CTS who underwent carpal tunnel release were enrolled. They underwent physical examination of the hand, nerve-conduction study, and magnetic resonance imaging (MRI) study of the wrist, and completed a patient-oriented questionnaire. The tests, except for MRI, were repeated 1, 3, and 6 months postoperatively. Synovial tissue was obtained during surgery and analyzed by Congo red and immunohistochemical staining. Ordinal logistic regression analysis was used to evaluate the significance of different clinical and subjective findings between patients with and without amyloid deposition. Postoperative improvements were also compared.

RESULTS

Wild-type transthyretin amyloid deposition was observed for 38 patients. Greater symptom severity and 2-point discrimination scores, and larger cross-sectional areas of the carpal tunnel, were significantly correlated with a larger amount of preoperative amyloid deposition. However, the presence and amount of preoperative amyloid deposition did not affect postoperative improvements in physical findings and nerve-conduction studies.

CONCLUSIONS

Although transthyretin amyloid deposition can worsen CTS symptoms, postoperative improvements were similar for patients with and without this deposition.

Delayed improvement after endoscopic carpal tunnel release

OBJECTIVE

In most patients with carpal tunnel syndrome (CTS), pain and/or paresthesia disappeared or decreased in a month after endoscopic carpal tunnel release (ECTR). However, subpopulation of patients showed delayed improvement following ECTR. We analyzed the delayed improvement hands to investigate the characteristics of those patients and to determine the predictable factors of delayed improvement.

METHODS

Single-portal ECTRs were performed in 1194 hands of 793 CTS patients from 2002 to 2011. Five-hundred seventy hands with minimal 1-year postoperative follow-up were included. We divided the 545 satisfied hands into early (group A) and delayed (group B) groups according to improvement period of 1 month. Demographic data, clinical severity and electrodiagnostic abnormality were compared between groups.

RESULTS

Group A included 510 hands and group B included 35 hands. In group B, 11 hands improved in 2 months, 15 hands in 3 months and 9 hands in 6 months, respectively. In group A/B, according to clinical severity, 60/1 hands were graded to I, 345/24 hands to II, 105/10 hands to III. In group A/B, based on electrodiagnostic abnormality, 57/3 hands were classified to mild, 221/11 hands to moderate and 222/21 hands to severe group. Statistical analysis between groups did not reach significance but electrodiagnostic or clinical severity had a tendency to affect the delayed response.

CONCLUSION

It is difficult to predict the factors contributing to postoperatively-delayed response in subpopulation of CTS patients. However, we recommend that postoperative observation for at least 6 months is necessary in patients without symptomatic improvement.

The role of ultrasound in the diagnosis and management of carpal tunnel syndrome: a new paradigm

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy, affecting 9% of women, and it is responsible for significant morbidity and occupational absence. Clinical assessment is used for initial diagnosis and nerve conduction (NC) studies are currently the principal test used to confirm the diagnosis. Sensitivity of NC studies is >85% and specificity is >95%. There is now good evidence that US can be used as an alternative to NC studies to diagnose CTS. US can assess the anatomy of the median nerve and also identify pathology of the surrounding structures that may compress the nerve. Median nerve enlargement (cross-sectional area ≥10 mm(2) at the level of the pisiform bone or tunnel inlet) is the most commonly used parameter to diagnose CTS on US, and sensitivity has been reported to be as high as 97.9% using this parameter. US may also be used to guide therapeutic corticosteroid injection into the carpal tunnel--thus avoiding median nerve injury--and to objectively monitor the response to treatment. There is now sufficient evidence to propose a new paradigm for the diagnosis of CTS that incorporates US. US is proposed as the initial diagnostic test in CTS based on similar sensitivity and specificity to NC studies but higher patient acceptability, lower cost and additional capability to assess carpal tunnel anatomy and guide injection.

Predominant patterns of median nerve displacement and deformation during individual finger motion in early carpal tunnel syndrome

Idiopathic carpal tunnel syndrome (CTS) is a common neuropathy, yet the pathologic changes do not explain the fleeting dynamic symptoms. Dynamic nerve-tendon interaction may be a contributing factor. Based on dynamic ultrasonographic examination of the carpal tunnel, we quantified nerve-tendon movement in thumb, index finger and middle finger flexion in normal subjects and those with mild-idiopathic CTS. Predominant motion patterns were identified. The nerve consistently moves volar-ulnarly. In thumb and index finger flexion, the associated tendons move similarly, whereas the tendon moves dorsoradially in middle finger flexion. Nerve displacement and deformation increased from thumb to index finger to middle finger flexion. Predomination motion patterns may be applied in computational simulations to prescribe specific motions to the tendons and to observe resultant nerve pressures. By identification of the greatest pressure-inducing motions, CTS treatment may be better developed. Symptomatic subjects displayed reduced nerve movement and deformation relative to controls, elucidating the physiologic changes that occur during mild CTS.

A handy review of carpal tunnel syndrome: From anatomy to diagnosis and treatment

Carpal tunnel syndrome (CTS) is the most commonly diagnosed disabling condition of the upper extremities. It is the most commonly known and prevalent type of peripheral entrapment neuropathy that accounts for about 90% of all entrapment neuropathies. This review aims to provide an outline of CTS by considering anatomy, pathophysiology, clinical manifestation, diagnostic modalities and management of this common condition, with an emphasis on the diagnostic imaging evaluation.

A comparison between ultrasonographic, surgical and histological assessment of tenosynovits in a cohort of idiopathic carpal tunnel syndrome patients

Carpal tunnel syndrome (CTS) may be caused by subclinical tenosynovitis which may be detected by ultrasonography (US). The objective of this study is to investigate whether ultrasonography has a place in the workup of idiopathic CTS patients. Therefore, we investigated the prevalence of tenosynovitis and its association with the clinical outcome of surgery. A cohort of 31 consecutive idiopathic CTS patients (33 wrists) who were a candidate for carpal tunnel release (CTR) surgery was assessed using greyscale ultrasonography (GSUS) and power Doppler ultrasonography (PDUS). Peroperatively, tenosynovitis was evaluated macroscopically by the surgeon. Tissue samples from areas macroscopically suspected for tenosynovitis were taken for histological evaluation. The clinical outcome of the operation was assessed after 6 months and if applicable alternative diagnoses for the CTS were proposed. US tenosynovitis (OMERACT) was detected preoperatively in 58 % of the wrists. Peroperatively, macroscopic tenosynovitis was detected visually in 88 % of the wrists. Histological evaluation demonstrated a limited influx of lymphocytes indicative of a mild chronic inflammatory response in 19 %. Non-specific reactive changes were observed in 78 % of the cases. Ultrasonographically defined tenosynovitis was associated with an OR of 2.81 (95 % CI 0.61-13) for responding well to surgery. Most cases of ultrasonographic and peroperatively defined tenosynovitis were classified by histology as reactive changes. The presence of ultrasonographic tenosynovitis might be associated with a better clinical outcome of surgery.

Effectiveness of mechanical traction as a non-surgical treatment for carpal tunnel syndrome compared to care as usual: study protocol for a randomized controlled trial

BACKGROUND

Carpal tunnel syndrome (CTS) is a common condition (prevalence of 4%) where the median nerve is compressed within the carpal tunnel resulting in numbness, tingling, and pain in the hand. Current non-surgical treatment options (oral medication, corticosteroid injections, splinting, exercise, and mobilization) show limited effects, especially in the long-term. Carpal tunnel release (CTR) surgery is effective in 70 to 75% of patients, but is relatively invasive and can be accompanied by complications. In an observational study, mechanical traction proved to be effective in up to 70% of patients directly after treatment and in 60% after two years follow-up. This randomized controlled trial (RCT) will examine the effectiveness of mechanical traction compared to care as usual in CTS.

METHODS/DESIGN

Patients diagnosed with CTS will be recruited from an outpatient neurology clinic and randomly assigned to the intervention group (mechanical traction) or the control group (care as usual). Participants in the intervention group will receive 12 treatments with mechanical traction during six consecutive weeks. Primary outcome is symptom severity and functional status, which are measured with the Boston Carpel Tunnel Questionnaire (BCTQ). Secondary outcomes are quality of life (WHOQOL-BREF), health related resource utilization, and absenteeism from work. Outcomes will be assessed at baseline, and at 3, 6, and 12 months after inclusion. Linear mixed effect models will be used to determine the change from baseline at 12 months on the BCTQ, WHOQOL-BREF, absenteeism from work and health related resource utilization. The baseline measurement, change from baseline at three and six months, as well as duration of symptoms until inclusion, age, gender, and co-morbidity will be included as covariates The Pearson's correlation coefficient will be generated to assess the correlation between depression and anxiety and treatment outcome.

DISCUSSION

Since current non-surgical treatment options are not effective long-term and CTR is relatively invasive, there is a need for an effective and non-invasive treatment option. Mechanical traction is a safe treatment option that may provide a good alternative for the usual care. Considering the prevalence of CTS, the study is of great clinical value to a large patient population.

TRIAL REGISTRATION

Clinical Trials NL44692.008.13 (registered on 19 September 2013).

Tumors and tumor-like lesions mimicking carpal tunnel syndrome

INTRODUCTION

Tumors and tumor-like lesions in or around the median nerve are uncommon causes of carpal tunnel syndrome (CTS). The purpose of the present study is to highlight the diagnostic approach and point out the profile of patients with CTS and potential underlying pathology.

MATERIALS AND METHODS

Twenty-eight patients with 32 affected hands had CTS correlated to a mass in or around the nerve. In 20 hands a palpable mass was present. Diagnostic workup included nerve conduction studies, ultrasound and/or MRI. Pre- and postoperative examination included two-point discrimination (2PD), grip strength, visual analogue scale (for pain) (VAS) and disabilities of the arm, shoulder and hand (DASH) scores.

RESULTS

Twelve of 28 patients were young (range 9-38 years) and 10 were male. Nerve compression was due to 27 extraneural lesions (8 abnormal muscles, 5 lipomas, 7 tenosynovitis, 4 vascular tumors, 2 ganglia, 1 Dupuytren's fibromatosis) and five intraneural tumors (three schwannomas, one neurofibroma, one sarcoma). Nerve decompression and excision of extraneural lesions were performed in all cases whereas in intraneural tumors, decompression was followed by excision in most cases and nerve grafting in one. Mean follow-up was 22 months (12-105 months). Extraneural masses were associated with a better outcome than nerve tumors. The mean postoperative VAS/DASH scores were 0.3/16.2 in extraneural lesions and 2.5/22 in intraneural lesions. The 2PD improved gradually in all patients (mean pre- and postoperative 12 and 5 mm). The mean grip strength increased from 28 to 31.3 kg postoperatively.

CONCLUSIONS

Although rare, the surgeon should include in the differential diagnosis of CTS the unusual cause of tumors and tumor-like lesions, especially when the patients' profile is not typical (young, male, no repetitive stress or manual labor). In addition, the presence of a palpable mass at the distal forearm or palm dictates the need for imaging studies. The extent, location and aggressiveness of the mass will determine the approach and type of procedure.

MID-MOTION DEFORMATION OF MEDIAN NERVE DURING FINGER FLEXION: A NEW INSIGHT INTO THE DYNAMIC AETIOLOGY OF CARPAL TUNNEL SYNDROME

Carpal tunnel syndrome (CTS) exists in a spectrum of severity and symptoms with a dynamic component. We aim to study dynamic nerve-tendon interrelationships in normal and mild CTS wrists during a fist motion, with dynamic ultrasound. We observed that in normal wrists, the nerve arcs in an ulnar-volar direction and changes from a circular shape to a flat oval during motion. In CTS candidates, however, the curvature and distance of the nerve's path are reduced, while nerve shape remains relatively constant. In all candidates, the nerve is compressed against the flexor retinaculum, with the nerve subject to less compression in normal candidates as it moves dorsally into a recess. These findings suggest that besides mechanical compression from increased carpal tunnel contents alone, a decrease in nerve gliding movement may lead to CTS symptomatology. Furthermore, we identified that maximum nerve deformation occurs mid-motion, supporting the use of wrist splints for symptom relief.

Investigating the Effectiveness of Full-Time Wrist Splinting and Education in the Treatment of Carpal Tunnel Syndrome: A Randomized Controlled Trial

This study investigated the effects of wearing a wrist support splint for 8 wk and receiving a formal education program on patients with carpal tunnel syndrome (CTS), as well as factors associated with patients’ desire to seek surgical intervention. Participants were recruited from a hospital surgical wait list and randomly assigned to an intervention group (n = 30) or a control group (n = 24). Significant improvements in measures of symptom severity and functional status over the duration of the study appeared in the intervention group but not in the control group. Logistic regression for the intervention group showed that symptom severity (odds ratio [OR] = 1.53, 95% confidence interval [CI] [1.20–1.93]), functional deficits (OR = 1.31, 95% CI [1.08–1.57]), pain score (OR = 1.25, 95% CI [1.11–1.61]), and symptom duration (OR = 1.11, 95% CI [1.01–1.24]) were positively associated with the desire to seek surgical intervention. This conservative CTS treatment program conducted by occupational therapists can improve symptoms and hand function in CTS patients.

Long-term effects of preserving or splitting the carpal ligament in carpal tunnel operation

Carpal tunnel syndrome is treated very successfully by surgical release of the flexor retinaculum. However, in some patients, all symptoms are not resolved. Weakness in grip strength and pain in the thenar and hypothenar areas corresponding to the end of the transverse ligament after its complete section have been described as common complications of classical neurolysis of the median nerve. This study presents here the long-term results of decompression operation of the median nerve at the wrist, conserving the transverse ligament, as well as its comparison with the classical open neurolysis with a complete section of the ligament. This is an analysis of a retrospective cohort of 114 patients, who were operated on for carpal tunnel syndrome. A clinical, electromyographic, and dynamometric evaluation of the patients studied was carried out in a comparative analysis of the surgical techniques used (flexor retinaculum lengthening according to the Simonetta technique and classical open neurolysis of the median nerve), in a period of 10 years after the operation. The ligamentoplasty technique, in the long-term, contributes to better results of manual force, with a smaller resolution of tingling sensations than the neurolysis with complete section of the transverse ligament. For those patients who do not present a severe clinical or electromyographic syndrome, and in addition require manual effort for their daily activities, the technique of ligamentoplasty, according to Simonetta, is a surgical option to be taken into account.

Compression and entrapment neuropathies

Peripheral nerve entrapments are frequent. They usually appear in anatomical tunnels such as the carpal tunnel. Nerve compressions may be due to external pressure such as the fibular nerve at the fibular head. Malignant or benign tumors may also damage the nerve. For each nerve from the upper and lower limbs, detailed clinical, electrophysiological, imaging, and therapeutic aspects are described. In the upper limbs, carpal tunnel syndrome and ulnar neuropathy at the elbow are the most frequent manifestations; the radial nerve is less frequently involved. Other nerves may occasionally be damaged and these are described also. In the lower limbs, the fibular nerve is most frequently involved, usually at the fibular head by external compression. Other nerves may also be involved and are therefore described. The clinical and electrophysiological examination are very important for the diagnosis, but imaging is also of great use. Treatments available for each nerve disease are discussed.

Early versus delayed endoscopic surgery for carpal tunnel syndrome: prospective randomized study

OBJECTIVE

To compare the effects of early versus delayed endoscopic surgery in patients with moderately severe carpal tunnel syndrome (CTS).

METHODS

The study included 100 patients with CTS. Investigations performed before surgery excluded secondary causes. Patients with moderately severe CTS (grade 3-4) were randomly assigned. Bland's neurophysiologic grading scale for CTS was used to assess the patients. Patients underwent an endoscopic carpal tunnel release using an indigenously designed instrument.

RESULTS

Following a course of conservative treatment, surgical treatment was offered in two groups: early surgery (n = 51; <1 week after diagnosis) and delayed surgery as per the usual waiting list (n = 49; >6 months after diagnosis). Improvement in both groups was significant (P < 0.001). When both groups were compared, improvement was better for the early surgery group (P < 0.001; confidence interval 6.35-9.12).

CONCLUSIONS

On the basis of this study, early endoscopic surgery is proposed in patients with moderately severe CTS.

Sonographically guided percutaneous needle release of the carpal tunnel for treatment of carpal tunnel syndrome: preliminary report

OBJECTIVES

The purpose of this study was to evaluate the effectiveness of a novel treatment procedure, sonographically guided percutaneous needle release of the carpal tunnel, for individuals with carpal tunnel syndrome.

METHODS

Seventeen patients (89% female; mean age, 62 years; SD, 13.6 years) with a clinical diagnosis of carpal tunnel syndrome who had undergone a sonographically guided percutaneous needle release of the carpal tunnel at least 6 months before follow-up evaluation were retrospectively reviewed. At the follow-up evaluation, to ascertain previous and current symptoms as well as functional impairment, the patients filled out a hand diagram and a questionnaire. In addition, medical records were reviewed, and patients were queried regarding complications such as infection or nerve damage. Median nerve sonographic measurements and a physical evaluation were performed on a subset of 13 patients who came to the office for evaluation.

RESULTS

Postprocedure sonography showed that patients had a significantly smaller (P = .03) cross-sectional area of the median nerve compared to pretreatment values. In addition, patients had significantly fewer symptoms (P < .0001), less functional impairment (P = .0002), and an improved hand diagram score (P < .0001). Postprocedure patients had grip strength that was 12 lb below average (≈1 SD below) compared to grip strength norms. However, most patients (84.6%) had negative clinical diagnostic test results for carpal tunnel syndrome, and 86% said they were satisfied with the procedure. There were no procedure-related infections or nerve injuries.

CONCLUSIONS

Of the patients with carpal tunnel syndrome who agreed to participate in this study, most had favorable symptomatic and functional outcomes. Sonographically guided percutaneous needle release of the carpal tunnel may be an alternative option to traditional surgical treatment of carpal tunnel syndrome.

Subsynovial connective tissue is sensitive to surgical interventions in a rabbit model of carpal tunnel syndrome

The most common histological finding in carpal tunnel syndrome (CTS) is non-inflammatory fibrosis and thickening of the subsynovial connective tissue (SSCT) in the tunnel. While the cause of SSCT fibrosis and the relationship of SSCT fibrosis and CTS are unknown, one hypothesis is that SSCT injury causes fibrosis, and that the fibrosis then leads to CTS. We investigated the sensitivity of the SSCT to injuries. Two types of surgical interventions were performed in a rabbit model: A skin incision with tendon laceration and SSCT stretching sufficient to damage the SSCT, and skin incision alone. Twelve weeks after surgery, the rabbit carpal tunnel tissues were studied with immunochemistry for TGF-β receptors 1, 2, and 3, collagen III, and collagen VI. All TGF-β receptors were expressed. The percentages of the TGF-β receptors' expressions were less in the control SSCT fibroblasts than in the fibroblasts from rabbits with surgical interventions. The surgical interventions did not result in any alteration of collagen III expression. However, both surgical interventions resulted in a significant decrease in collagen VI expression compared to the control group. The two surgical interventions achieved similar expression of TGF-β receptors and collagens. Our results provide evidence that the SSCT is sensitive to surgical interventions, even when these are modest. Since SSCT fibrosis is a hallmark of CTS, these data also suggest that such fibrosis could result from relatively minor trauma.

Carpal tunnel syndrome: a review of the recent literature

Carpal Tunnel Syndrome (CTS) remains a puzzling and disabling condition present in 3.8% of the general population. CTS is the most well-known and frequent form of median nerve entrapment, and accounts for 90% of all entrapment neuropathies. This review aims to provide an overview of this common condition, with an emphasis on the pathophysiology involved in CTS. The clinical presentation and risk factors associated with CTS are discussed in this paper. Also, the various methods of diagnosis are explored; including nerve conduction studies, ultrasound, and magnetic resonance imaging.

High prevalence of wild-type transthyretin deposition in patients with idiopathic carpal tunnel syndrome: a common cause of carpal tunnel syndrome in the elderly

Carpal tunnel syndrome is the most common type of entrapment neuropathy. However, the cause of carpal tunnel syndrome remains unclear in most cases. Senile systemic amyloidosis, induced by wild-type transthyretin deposition, is a prevalent aging-related disorder and often accompanied by carpal tunnel syndrome. In this study, we measured the frequency of unrecognized wild-type transthyretin deposition in patients with idiopathic carpal tunnel syndrome. One hundred twenty-three patients with carpal tunnel syndrome, including 100 idiopathic patients, treated by carpal tunnel release surgery were analyzed. Tenosynovial tissues obtained at surgery were analyzed by Congo red and immunohistochemical staining. If staining for transthyretin was positive, the entire transthyretin gene was analyzed by direct DNA sequencing. We also analyzed tenosynovial tissues from 32 autopsy cases as controls. Thirty-four patients (34.0%) with idiopathic carpal tunnel syndrome showed amyloid deposition in the tenosynovial tissue, and all amyloid showed specific immunolabeling with antitransthyretin antibody. Direct DNA sequencing of the entire transthyretin gene did not reveal any mutations, indicating that all amyloid deposits were derived form wild-type transthyretin. Statistical analysis using logistic regression showed that the prevalence of transthyretin deposition in the idiopathic carpal tunnel syndrome group was significantly higher than that in controls (odds ratio, 15.8; 95% confidence interval, 3.3-5.7), and age and male sex were independent risk factors for transthyretin amyloid deposition. Our results demonstrate that wild-type transthyretin deposition is a common cause of carpal tunnel syndrome in elderly men. It is likely that many patients develop carpal tunnel syndrome as an initial symptom of senile systemic amyloidosis.

Color and power Doppler US for diagnosing carpal tunnel syndrome and determining its severity: a quantitative image processing method

PURPOSE

To determine whether intraneural vascularity seen at color Doppler ultrasonography (US) can be used to diagnose carpal tunnel syndrome (CTS) and to evaluate an image processing method for quantifying the severity of CTS on the basis of this vascularity.

MATERIALS AND METHODS

This study was approved by the university ethics review committee. One hundred one patients with clinical evidence of CTS and 55 healthy control subjects were enrolled. Electrodiagnostic testing (EDT) was performed in all participants, and the presence of intraneural vascularity was evaluated with color Doppler US. An image processing program was designed by using software to determine the sum of pixels in the intraneural vascular area on power Doppler US scans of the median nerve. The relationship between the number of pixels and the severity of the abnormality at EDT was determined.

RESULTS

The sensitivity (83%) and specificity (89%) of intraneural vascularity in the diagnosis of CTS were similar to those of EDT (81% and 84%, respectively). Intraneural vascularity was seen in 91.4% of patients with mild CTS and 100% of patients with moderate or severe CTS. In participants with positive intraneural vascularity, the sum of pixels in the intraneural vascular area was significantly higher in patients than in control subjects and paralleled the severity of the abnormality at EDT (P < .01).

CONCLUSION

Color Doppler US can be used to accurately diagnose CTS. By processing the recorded power Doppler images and determining the number of pixels in the intraneural vascular area, the severity of CTS can be assessed. 2011 SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11110150/-/DC1.

Carpal tunnel syndrome in fabry disease

Carpal tunnel syndrome (CTS) is a common peripheral mononeuropathy affecting up to 4% of the general population, typically women in late middle age. The incidence in patients with Fabry disease (FD) is unclear, but may affect 25% of patients with this X-linked lysosomal storage disease. We report three cases of CTS in young Caucasian male patients with classical FD, who developed CTS symptoms with supportive nerve conduction study (NCS) findings. Two patients had bilateral CTS and two had evidence of concurrent ulnar nerve neuropathy on NCS, suggesting a systemic process contributed to nerve compression. All were receiving enzyme replacement therapy (ERT) and had a moderate burden of FD complications. It is possible that an increase in connective tissue in the intracarpal canal in FD patients may be incited by injury to fibroblasts, via either accumulation of globotriaosylceramide (GL3) or local ischaemia through endothelial injury. The former hypothesis may be a more plausible explanation for the development of CTS, as histology of the flexor retinaculae from our patients has demonstrated fibroblasts with characteristic vacuolation and excessive myxomatous stroma, despite endothelial clearance of GL3 in these patients receiving ERT. CTS should not be overlooked in FD patients and young patients presenting with CTS should be evaluated for an underlying systemic or genetic disorder. Surgical carpal tunnel decompression was effective in our patients, already troubled by long-standing acroparesthesia, in providing sustained relief of symptoms.

Serum CXCL10 levels and neuromuscular manifestations in patients with autoimmune thyroid diseases

OBJECTIVE

Serum C-X-C motif chemokine 10 (CXCL10) levels have been shown to be elevated in autoimmune thyroid diseases (AITD). This study sought to determine whether newly diagnosed AITD patients with neuromuscular findings had higher levels of CXCL10 than those without neuromuscular manifestations.

DESIGN

A total of 80 patients were recruited to the study, which included treatment-naive hypothyroid Hashimoto's thyroiditis (n = 19) and hyperthyroid Graves' disease (GD; n = 21), euthyroid thyroid autoantibody-positive (n = 20) and -negative (n = 20) patients.

METHODS

All patients underwent a thorough sensorimotor and neuromuscular examination. Serum samples were kept in - 20°C for further CXCL10 measurements with ELISA.

RESULTS

There was a significant difference with regard to serum CXCL10 levels only between GD and euthyroid thyroid autoantibody-negative patient groups [187(12-418) vs. 37.5(2-542) pg/ml, p < 0.05]. However, a comparison of newly diagnosed AITD patients with and without neuromuscular manifestations in terms of serum CXCL10 levels yielded no significant difference. When a correlation of existence of a neuromuscular manifestation and serum CXCL10 levels was evaluated, a significantly positive correlation was noted between carpal tunnel syndrome (CTS) and serum CXCL10 levels [207 (95-748) pg/ml in CTS-positive vs. 117 (2-977) pg/ml in CTS-negative patients, p < 0.05].

CONCLUSIONS

In this study, from a number of neuromuscular manifestations, only the existence of CTS correlated with significantly higher CXCL10 levels in the whole study group. Further studies with larger numbers of patients with autoimmune-based hyper- and hypothyroidism may better clarify the hypothesis regarding a relationship between serum CXCL10 levels and neuromuscular manifestations of AITD.

Combination of high-resolution and color Doppler ultrasound in diagnosis of carpal tunnel syndrome

BACKGROUND

Ultrasound has recently emerged as a diagnostic tool in carpal tunnel syndrome (CTS).

PURPOSE

To evaluate the utility of a combination of high-resolution and color Doppler ultrasound as an alternative to electrodiagnostic tests (EDT), in CTS diagnosis, and to define an ultrasonographic prediction model for CTS.

MATERIAL AND METHODS

A total of 85 patients with certain clinical diagnosis of CTS and 49 healthy controls were enrolled. High-resolution and color Doppler ultrasound were performed and the cross-sectional area (CSA), hypoechogenicity, and hypervascularity of the median nerve were evaluated. Receiver-operating characteristic curves were used to determine the optimal cut-off point of median nerve CSA in diagnosis of CTS. Multivariate logistic regression analysis was used to formulate a prediction model for CTS.

RESULTS

The optimal cut-off point of median CSA in wrist was 10.5 mm(2). Hypervascularity (OR = 37.95), hypoechogenicity (OR = 12.30), and high CSA (OR = 34.79) of median nerve were significantly (P < 0.001) higher in CTS patients than in controls. No significant difference was found between the sensitivity and specificity of EDT and any of the above indices in prediction of CTS. An ultrasonographic model for prediction of CTS, comprised hypervascularity and/or high CSA of median nerve, could predict the CTS probability between 87-99%. The sensitivity and specificity of this model (86% and 84%) was not different from EDT (80% and 84%).

CONCLUSION

A combination of high-resolution and color Doppler ultrasound can be used as a non-invasive alternative to EDT in diagnosis of CTS.