Schrier, Verena J.M.M.

Abstract Objective: The incidence of carpal tunnel syndrome (CTS) is higher in women, and peaks around the age of menopause. Therefore, we investigated whether bilateral oophorectomy is associated with an increased risk of severe CTS. Methods: We included all of the 1,653 premenopausal women who underwent bilateral oophorectomy for a nonmalignant indication between 1988 and 2007, and a random sample of 1,653 age-matched referent women who did not undergo bilateral oophorectomy in Olmsted County, MN. Diagnoses of CTS assigned to women over their entire lifetime were identified in these two cohorts. The risk of de novo severe CTS after bilateral oophorectomy (or index date) was evaluated using Cox proportional hazards models adjusted for potential confounders. Results: Bilateral oophorectomy was associated with an increased risk of severe CTS (adjusted hazard ratio 1.65, 95% confidence interval 1.20-2.25). The risk was suggestively greater in women with lower body mass index, nulliparity, and with a benign ovarian indication for oophorectomy (nonsignificant interactions). We did not observe a protective effect of estrogen therapy after the oophorectomy. The findings were similar in secondary analyses considering the incidence of CTS of any severity or idiopathic CTS. Conclusions: The risk of severe CTS, common in perimenopausal women, is increased after bilateral oophorectomy. The association may be causal or due to confounding. Therefore, the precise biological mechanisms explaining the association and the absence of a mitigating effect of estrogen therapy should be further investigated.

ObjectivesThe mobility (transverse movement) of the median nerve (MN) is decreased in patients with carpal tunnel syndrome and can be measured noninvasively by ultrasound. To date, there are few prognostic features to help predict the outcome of 2 commonly performed treatments: surgical carpal tunnel release and corticosteroid injection. This study aimed to assess the changes in nerve mobility after the intervention and to correlate this with treatment and the disease severity.MethodsA total of 181 patients with carpal tunnel syndrome with different electrophysiologic severities were recruited and assessed by dynamic ultrasound scanning of the MN before and after treatment. The dynamic ultrasound images were collected while the patients performed finger and wrist flexion.ResultsFor both injection and carpal tunnel release, the nerve displacement increased with wrist flexion, from a mean ± SD of 7.0 ± 2.4 to 7.9 ± 2.7 mm (P < .005). Patients who underwent surgery showed greater improvement (P < .005) in nerve mobility compared to those who underwent injection. We also observed that the increase in nerve mobility was predominantly in patients with more nerve damage at baseline.ConclusionsThis study shows that the dynamic behavior of the MN changes in response to treatment and lays a foundation for future studies to assess the prognostic potential of nerve mobility measurement.

Ultrasound guidance in the operative treatment of carpal tunnel syndrome is gaining in popularity as it noninvasively provides the surgeon with a real-time high-resolution overview of anatomic structures. A new incision-less approach to achieve a division of the transverse carpal ligament has been developed that combines ultrasound guidance with cannulated needles and a thread. Conceptually, an abrasive thread is looped percutaneously around the ligament while avoiding injury to neurovascular structures, the palmar aponeurosis, and skin. The thread is positioned using 2 puncture sites and a contoured Tuohy needle under ultrasound visualization. With a minimal injury to surrounding structures, this approach is designed to minimize recovery time and decrease pillar pain. This article will provide a step-by-step overview of the technique and includes a review of clinical outcomes published so far.

Abstract The carpal tunnel contains the digital flexor tendons and the median nerve, which are embedded in a unique network of fibrovascular interconnected subsynovial connective tissue (SSCT). Fibrous hypertrophy of the SSCT and subsequent adaptations in mechanical response are found in patients with carpal tunnel syndrome (CTS), but not much is known about the development of the SSCT. This observational study describes the morphological development of SSCT using histology and ultramicroscopy in an animal model at four time points between late‐term fetuses through adulthood. A transition is seen between 3 days and 6 weeks post‐partum from a dense solid SSCT matrix to a complex multilayered structure connected with collagenous fibrils. These preliminary data show a developmental pattern that matches an adaptive response of the SSCT to loading and motion. Understanding the anatomical development aids in recognizing the pathophysiology of CTS and supports research on new therapeutic approaches.

ObjectivesCorticosteroid injections can provide (temporary) relief in patients with mild to moderate carpal tunnel syndrome (CTS). Hydrodissection as part of an injection has been associated with positive clinical outcomes but data for CTS so far has been scarce. This study is designed to assess patient tolerance and secondarily provide pilot data on the added effect of hydrodissection.MethodsTwenty CTS patients were randomized to an ultrasound‐guided betamethasone injection with hydrodissection (5 mL) or without (2 mL). Patient tolerance was assessed directly after intervention and patient‐reported outcome after 4 and 24 weeks. Intra‐group data were compared using Wilcoxon Signed Rank and inter‐group with Wilcoxon rank‐sum tests.ResultsTolerance and pain scores did not differ between the two groups. Symptom scores decreased in both groups, but to a lesser extent in the hydrodissection group with a mean difference of −0.8 versus −1.5 in the control group at 4 weeks (P = .02). At 6 months, this difference was no longer present (P = .81). No statistically significant differences were found between the hydrodissection and control groups in the function or pain scores at follow‐up at either time point.ConclusionAfter injection, both symptomatic and functional scores improved, but the hydrodissected group did not show additional improvement. Data presented can be used to support larger studies to assess the value of hydrodissection in CTS management.

AbstractBackgroundShear wave elastography (SWE) shows promise in peripheral neuropathy evaluation but has potential limitations due to tissue size and heterogeneity. We tested SWE sensitivity to elasticity change and the effect of probe position in a median nerve cadaver model.MethodsTen specimens were used to measure median nerve elasticity under increasing loads using SWE and indentation. Measurements were compared using repeated‐measures analysis of variance.ResultsIndentation and SWE‐based longitudinal nerve elasticity increased with tensile loading (P< .01), showing a similar relationship. Acquisition in a transverse plane showed lower values compared with longitudinal measurements, mostly under higher loads (P= .03), as did postdissection elasticity (P= .02). Elasticity did not change when measured proximal to the carpal tunnel.ConclusionsLongitudinal SWE is sensitive to changes in median nerve elasticity. Measuring elasticity of peripheral nerves noninvasively could elucidate intra‐neural pathology related to compression neuropathies, and proof to be of added value as a diagnostic or prognostic tool.

Background: In hand surgery, and specifically carpal tunnel syndrome, it is currently unknown whether experiences with health care influence surgical outcome. To investigate whether there is an association between patient-reported experience measures and symptom relief, data were gathered using a cohort of patients undergoing surgical treatment for carpal tunnel syndrome. Methods: Patient-reported experience measures and patient-reported outcome measures were registered in a national database of 16 hand surgery practices. The experience measure data were gathered at 3 months after surgery and included six subscales on different health care delivery aspects (e.g., provided information, communication, facility, operative care). The outcome measure data were acquired before and 3 months after surgery with the Boston Carpal Tunnel Assessment Questionnaire. The association was tested using linear regression analyses. Results: A total of 1607 patients were included in the analysis. The experience measure scores were good to excellent, with a median value between 8.0 and 8.5 on a 10-point scale. Regression analyses showed a significant (p < 0.001) association with the Boston Carpal Tunnel Assessment Questionnaire for all individual patient-reported experience measure subscales. The greatest effects were found in physician communication and treatment information. Patient-reported experience measures accounted for more than 5 percent of the explained variance, with patient characteristics explaining an approximately additional 3 percent. Conclusions: In this large data set of carpal tunnel syndrome patients who underwent surgical release, a significant impact of health care experiences on self-reported clinical outcome was found. This is relevant information, not only for directing care providers in improving health care experiences as a quality-of–health care measure but now also potentially to achieve better clinical outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.