Outcome after carpal tunnel release: effects of learning curve.

INTRODUCTION: In carpal tunnel release, it is yet unclear whether a learning curve exists among surgeons. The aim of our study was to investigate if outcome after carpal tunnel release is dependent on surgeon's experience and to get an impression of the learning curve for this procedure. METHODS: A total of 188 CTS patients underwent carpal tunnel release. Patients completed the Boston Carpal Tunnel Questionnaire at baseline and 6-8 months postoperatively together with a six-point scale for perceived improvement. RESULTS: Patients operated by an experienced resident or certified surgeon reported a favorable outcome more often than patients operated by an inexperienced resident (adjusted OR 3.23 and adjusted OR 3.16, respectively). In addition, a negative association was found between surgeon's years of experience and postoperative Symptom Severity Scale and Functional Status Scale scores. DISCUSSION: Outcome after carpal tunnel release seems to be dependent on surgical experience, and there is a learning curve in residents.

Bifid median nerve in carpal tunnel syndrome: do we need to know?

INTRODUCTION: We tested the hypothesis that a bifid median nerve predisposes to development of carpal tunnel syndrome (CTS) and investigated differences in electrophysiological findings and outcome. METHODS: A total of 259 consecutive patients with clinically defined CTS were included and investigated clinically, electrophysiologically, and ultrasonographically. Fifty-four healthy asymptomatic volunteers were investigated ultrasonographically. RESULTS: The prevalence of bifid median nerves is equal in patients with CTS and controls. Electrophysiological and ultrasonographic abnormalities are more pronounced in patients with non-bifid median nerves. Some outcome data are better in patients with non-bifid median nerves, but others do not show significant differences. CONCLUSIONS: A bifid median nerve is not an independent risk factor for development of CTS. Some of our data suggest outcome after surgical decompression to be different, but others do not. The surgical technique in these patients may therefore have to be reevaluated.

Ultrasonography in severe carpal tunnel syndrome.

INTRODUCTION: In up to 30% of patients with carpal tunnel syndrome (CTS), the cross-sectional area (CSA) of the median nerve may not be enlarged. We hypothesize that this could be the result of secondary atrophy of the nerve in severe CTS. The aim of this study was to measure the ultrasonographic CSA of the median nerve at the wrist in patients with severe CTS. METHODS: In 14 consecutive patients with clinically and electrophysiologically defined severe CTS, the CSA of the median nerve was measured and compared with that of control subjects. RESULTS: CSA of the median nerve exceeded the upper limit of normal in the majority of patients with severe CTS. CONCLUSIONS: Atrophy of the median nerve in severe CTS does not explain negative ultrasonographic test results. Instead, the CSA of the median nerve is enlarged in most patients with severe CTS.

Augmented Diagnostic Accuracy of Ultrasonography for Diagnosing Carpal Tunnel Syndrome Using an Optimised Wrist Circumference-Dependent Cross-Sectional Area Equation.

Introduction: In diagnosing carpal tunnel syndrome (CTS) there is no consensus about the upper limit of normal (ULN) of the cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet. A previous study showed wrist circumference is the most important independent predictor for the ULN. In this study we optimised a wrist circumference-dependent ULN equation for optimal diagnostic accuracy and compared it to the generally used fixed ULN of 11 mm2. Methods: CSA and wrist circumference were measured in a prospective cohort of 253 patients (clinically defined CTS) and 96 healthy controls. An equation for the ULN for CSA was developed by means of univariable regression analysis. We calculated z-scores for all patients and healthy controls, and analysed these scores in a ROC curve and a decision plot. Sensitivity and specificity were determined and compared to fixed ULN values. Results: We found augmented diagnostic accuracy of our newly developed equation y = 0.88 * x -4.0, where y = the ULN of the CSA and x = wrist circumference. This equation has a corresponding sensitivity and specificity of 75% compared to a sensitivity of 70% while using a fixed cut-off value of 11 mm2 (p = 0.015). Conclusion: Optimising the regression equation for wrist circumference-dependent ULN cross-sectional area of the median nerve at the wrist inlet might improve diagnostic accuracy of ultrasonography in patients with carpal tunnel syndrome and seems to be more accurate than using fixed cut-off values.

Motor Nerve Conduction Tests in Carpal Tunnel Syndrome.

Background: For the preoperatively often required confirmation of clinically defined carpal tunnel syndrome (CTS), sensory as well as motor nerve conduction studies can be applied. The aim of this study was to test the sensitivity of specific motor nerve conduction tests in comparison with, as well as in addition to, sensory nerve conduction tests. Methods: In 162 patients with clinically defined CTS, sensory and motor nerve conduction tests were performed prospectively. Sensitivity and specificity of all tests were computed. Also, Receiver Operating Characteristic (ROC) analyses were conducted. Results: Sensitivity for all sensory tests was at least 79.4% (DIG1). All tests had a specificity of at least 95.7%. The motor conduction test with the highest sensitivity was the TLI-APB (81.3%); its specificity was 97.9%. Conclusion: In the electrophysiological confirmation of CTS, sensory nerve conduction tests and terminal latency index have a high sensitivity. If, however, sensory nerve action potentials cannot be recorded, all motor nerve conduction tests have a high sensitivity.

Acute isodense intracerebral haematoma due to coagulopathy associated with prostate cancer.

Prostate cancer can be complicated by spontaneous intracranial haematoma. In the acute setting, an intracranial haematoma can appear isodense on CT scanning, especially if a coagulopathy is present. Diffuse intravascular coagulation (DIC) can be the underlying pathophysiological mechanism that leads to spontaneous bleeding. It is important to recognize the possibility of DIC in cancer patients, since it has important therapeutical implications that may be life saving.

Treatment outcome in patients with clinically defined carpal tunnel syndrome but normal electrodiagnostic test results: a randomized controlled trial.

Little is known about treatment effect of carpal tunnel release in patients with clinically defined carpal tunnel syndrome (CTS), but normal electrodiagnostic test results (EDX). The aim of this study was to determine whether this category of patients will benefit from surgical treatment. 57 patients with clinically defined CTS and normal EDX were randomized for surgical treatment (n = 39) or non-surgical treatment (n = 18). A six-point scale for perceived improvement as well as the Boston Carpal Tunnel Questionnaire was completed at baseline and at follow-up after 6 months. A significant improvement of complaints was reported by 70.0% of the surgically treated patients and 39.4% reported full recovery 6 months after surgery. Furthermore, both Functional Status Score and Symptom Severity Score improved significantly more in the surgically treated group (p = 0.036 and p < 0.001, respectively). This study demonstrates that most patients with clinically defined CTS and normal EDX results will benefit from carpal tunnel release. Therefore, this group of CTS patients must not a priori be refrained from surgery.

Treatment outcome in carpal tunnel syndrome: does distribution of sensory symptoms matter?

BACKGROUND: Patients with complaints of carpal tunnel syndrome (CTS) with signs and symptoms not exclusively confined to the median nerve territory, but otherwise fulfilling the clinical criteria may erroneously be withheld from therapy. METHODS: One hundred and twenty one patients who fulfilled the clinical criteria for the diagnosis of CTS with signs and symptoms restricted to the median nerve territory (group A) and 91 patients without this restriction (group B) were included in a prospective cohort study. All patients fulfilled electrodiagnostic criteria of CTS. Outcome was determined after 7 to 9 months by means of Symptom Severity Score (SSS) and Functional Status Score (FSS) according to Levine and a patient satisfaction questionnaire. RESULTS: Response rates were 81.8% (group A) and 82.4% (group B). All patients in group B had sensory symptoms involving digit 5. There were no significant differences in improvement of SSS, FSS and patient satisfaction scores between groups after treatment. CONCLUSION: CTS patients with characteristic sensory signs and symptoms not exclusively restricted to the median nerve innervated area should be treated in the same manner as patients with CTS symptoms restricted to the median nerve innervated area and should therefore not be withheld from surgical treatment.

Comparison of peak versus onset latency measurements in electrodiagnostic tests for carpal tunnel syndrome.

PURPOSE: The aim of this prospectively conducted study was to compare the diagnostic accuracy of onset versus peak latency measurements of sensory nerve action potentials in electrodiagnostic studies in diagnosing carpal tunnel syndrome. METHODS: In 156 consecutive patients with clinically defined carpal tunnel syndrome, standardized nerve conduction studies (DIG1, DIG4, PALM3) were performed. Both onset and peak latency were measured. Sensitivity was calculated using the clinical diagnosis as golden standard. Bland-Altman plots were constructed to assess the agreement for quantitative measurements. Overall agreement, positive and negative percent agreement, and Kappa coefficient were computed. RESULTS: The Bland-Altman plots, positive and negative percent agreement show good overall agreement. The kappa coefficient was 0.850, 0.847, and 0.815 for DIG1, DIG4, and PALM3, respectively. CONCLUSIONS: Onset and peak latencies used in electrodiagnostic tests show a good overall agreement in confirming the clinical diagnosis of carpal tunnel syndrome. Because onset latency measurement represents nerve conduction velocity of the fastest conducting fibers, the use of onset latencies is recommend. In case of uncontrollable stimulus artifacts, peak latencies may be used instead.

Comparing a new ultrasound approach with electrodiagnostic studies to confirm clinically defined carpal tunnel syndrome: a prospective, blinded study.

OBJECTIVE: The aims of this study were to compare electrodiagnostic (EDX) confirmation of clinical diagnosis of carpal tunnel syndrome (CTS) with ultrasonography (US), using a new set of normal values taking wrist circumference of subjects into account, and to determine whether EDX examination can be replaced by US to confirm CTS. DESIGN: A prospective cohort of 156 patients with idiopathic CTS underwent US and EDX studies. Upper levels of normal cross-sectional area of the median nerve were established by taking wrist circumference into account and using linear regression equations. RESULTS: Of the selected patients, 83.3% met the EDX criteria for CTS. The findings from the US were normal in 67 (42.9%) of 156 patients, and within this group, the findings from the EDX were abnormal in 44 patients (65.7%). Of 89 patients with abnormal findings from the US, only 3 patients had normal findings from the EDX. CONCLUSIONS: US cannot replace EDX for confirmation of clinical diagnosis of CTS. However, an abnormal US test result has a high positive predictive value for abnormal EDX result in clinically defined CTS. US might reveal relevant anatomic information preoperatively that rarely has a direct influence on treatment management of patients with CTS. US testing, taking morphometric data into account, does not have the same diagnostic value as EDX does in confirming CTS.

The segmental palmar test in diagnosing carpal tunnel syndrome reassessed.

OBJECTIVE: To test our hypothesis that comparing the sensory nerve conduction velocity of the median nerve across the wrist with that of the forearm is more sensitive than comparing it with that of the palm in the electrodiagnostic confirmation of carpal tunnel syndrome (CTS). METHODS: One hundred and fifty seven consecutive patients with clinically defined CTS were prospectively included and electrophysiologically examined. Antidromic nerve conduction velocities were measured in 3 segments of the median nerve: forearm, wrist, and palm. Differences and ratios in nerve conduction velocities were computed between the forearm and wrist and between the palm and wrist segments. RESULTS: Comparing the median nerve conduction velocities of the forearm with the wrist segment provides a greater sensitivity (79.6% and 82.8% for the second and third digit, respectively) than comparing the palm with the wrist segment (65.6% and 65.0%). Applying the ratio leads to slightly higher sensitivities for both comparisons. CONCLUSIONS: The modified segmental palmar test is a sensitive, robust and easily applicable method in diagnosing CTS. SIGNIFICANCE: We recommend to use the median nerve sensory conduction velocity in the forearm as a reference in the segmental palmar test instead of that in the palm.