THU0310 Predictors of Therapeutic Success of Steroids Injection in the Carpal Tunnel Syndrome: A Retrospective Multivariate Analysis of A Multicenter Cohort

Abstract

Background Treatment of moderate to severe carpal tunnel syndrome includes the possibility of local steroid injections, however the treatment success rate and its duration are very variable. There is no study designed to predict if a local steroid injection will be success or not. Sometimes local steroids injections delays surgical procedures without solving patient symtoms. A marker capable to predict success of failure should be useful in terms of chosing best therapy for these patients. Objectives The purpose of this study was to determine the weight of different factors as predictors of the therapeutic success of steroid joint injections. Methods We conducted a retrospective study with a cohort of 166 patients diagnosed with moderate or severe carpal tunnel syndrome according to electrophysiological criteria and who had undergone carpal ultrasound between 2010 and 2013. A multivariate analysis, using as the variable response a reduction in the score at the Boston Carpal Tunnel Syndrome Questionnaire three months after the steroid infiltration was performed. Results The presence of positive power- Doppler signal in the carpal tunnel showed a high correlation with the improvement at the Boston Carpal Tunnel Syndrome Questionnaire (Pearson r -0.7079, p=0.0001) in the bivariate analysis, and a ratio of 49.8% in the multivariate analysis (Heat coeff -0.4777 [95% CI -1.4775 to -0.5612], p<0.0001). Other relevant variables were: duration of symptoms (Heat coeff 0.0071 [95% CI 0.0025 to 0.0117], p=0.0027), the cross-sectional area of the median nerve within the carpal tunnel (Heat coeff 0.0223 [95% CI 0.0023 to 0.0424], p=0.0293) and age (0.0029 Heat coeff [CI -0.0005 to 0.0064], p=0.0979). Conclusions Our results suggest that the therapeutic success of infiltration is mainly associated with the finding of power- Doppler signal. According to our analysis we believe it is reasonable to recommend steroids joint injections in patients with this finding and to consider the risk/benefit in patients without this sonographic predictor. Acknowledgements To Dr. Domingo Ly Pen for his contribution to this study. Disclosure of Interest : None declared DOI 10.1136/annrheumdis-2014-eular.5556

Systematic Review of the Use of Power Doppler Ultrasound in the Imaging of Peripheral Nerve Compression Neuropathy

“…Another study retrospectively evaluated clinical outcomes after steroid injection in 166 wrists with moderate to severe carpal tunnel syndrome to determine predictors of improved Boston Carpal Tunnel Questionnaire scores at 3 months and found that therapeutic success highly correlated with power Doppler signal at diagnosis. 20 This agrees with findings from a prospective study of 40 wrists assessing response to treatment with ultrasonography and electrodiagnostic studies in which only power Doppler ultrasound had significant correlation with improvement in Boston Carpal Tunnel Questionnaire and visual analogue scale pain scores at 6 weeks. 35 In contrast, one study evaluated clinical outcomes using the Disabilities of the Arm, Shoulder and Hand instrument; the Boston Carpal Tunnel Questionnaire; and visual analogue scale pain and physician assessment questionnaires, finding no significant correlations with semiquantitatively graded power Doppler signals.…”

“…31,32,36 Some researchers looked at accuracy in detecting prognosis of treatment and patient satisfaction. 7,20,23,35 Biases Risks of biases were considered in the interpretation and applicability of results. Retrospective selection of patients in three studies 20,28,29 could lead to verification and detection biases.…”

“…24 One retrospective study evaluated response to steroid injection therapy in patients with moderate to severe carpal tunnel syndrome. 20 Patient cohorts in at least two studies were obese. 24,31 One group used the same cohort for two similar studies.…”

“…24,[29][30][31] Comparator Clinical diagnosis was the reference standard in nine studies, 16,24,27,[31][32][33][38][39][40] and electrophysiologic diagnosis was the reference standard in the rest. Almost all studies compared power Doppler ultrasound with at least one other form of ultrasound, whereas some compared it to electrodiagnostic studies, 7,8,11,13,[20][21][22][23][25][26][27][29][30][31][32][33][34][35][36][37][38][39] magnetic resonance imaging, 25 patient-reported outcomes, 7,20,23,35 or other measures. 51e Intervention All included studies used power Doppler ultrasound either alone or in combination with other diagnostic methods.…”

Ultrasound Assessment of the Median Nerve Does Not Adequately Discriminate the Carpal Tunnel Syndrome among Patients Diagnosed with Diabetes

“…Recently, attempts have been made to evaluate the role of carpal ultrasound in the diagnosis of CTS [7][8][9][10]. In all cases, the initiative to validate ultrasound as a diagnostic tool is justified by its greater availability and accessibility.…”