Local Steroid Injection vs Placebo in Carpal Tunnel Syndrome
Condition: Carpal Tunnel Syndrome
MeSH terms: Carpal Tunnel Syndrome; Syndrome
Study type: Interventional
Phase: Phase 4

Summary: 
      Between 2008 and 2012 the investigators performed a single-center randomized double-blind
      placebo-controlled trial to assess the efficacy of local injection of two different doses of
      methylprednisolone (80 mg and 40 mg) in patients with carpal tunnel syndrome (CTS), aged 18
      to 70 years, not previously treated with steroid injection. The primary outcomes were change
      in the CTS symptom severity score at 10 weeks and rate of carpal tunnel release surgery on
      the study hand at 1 year. In the trial 111 patients were randomized (37 in each of the 3
      groups: 80 mg methylprednisolone, 40 mg methylprednisolone and placebo) and all completed the
      1-year follow-up. The investiators plan an extended follow-up 5 to 7 years after injection.
    

Detailed description: 
      Extended follow-up protocol:

      All 111 trial participants will be contacted by telephone by a researcher and given
      information about this extended follow-up. A questionnaire together with written information
      and consent forms will be sent by mail. The questionnaire consists of the CTS symptom
      severity sale, 11-item DASH scale, bodily pain scale, and a treatment satisfaction visual
      analog scale (VAS), that were used in previous follow-up evaluations. The questionnaire will
      also include the 6-item CTS symptoms scale (CTS-6) and the palmar pain scale. The patients
      will be asked whether and when they had undergone carpal tunnel release surgery on the study
      hand after they received the injection within the trial. Patients' records will be reviewed
      to verify data about subsequent surgery on the study hand.

      The Chi-square test will be used to compare the 80-mg methylprednisolone group and the
      placebo group with regard to the proportion of patients who have had carpal tunnel release
      surgery on the study hand within 5 years after injection (primary outcome). The change in
      symptom severity score in patients in the 80-mg methylprednisolone group who did not have
      surgery on the study hand after injection will be compared with the change in symptom
      severity score in patients who had surgery on the study hand after methylprednisolone
      injection (co-primary outcome) using analysis of covariance (ANCOVA) adjusting for sex, age,
      dominance of the study hand and baseline symptom severity score. A similar comparison will be
      made for the 11-item DASH and the bodily pain scores. The palmar pain score at 5 to 7 years
      will be compared between the groups using the independent-samples t-test and also ANCOVA to
      adjust for sex, age and dominance of the study hand. Patients who had surgery after
      methylprednisolone injection will be compared with patients who had surgery after placebo
      injection with regard to change from baseline to 5 to 7 years in the symptom severity score,
      11-item DASH scale score, bodily pain score and satisfaction score using ANCOVA adjusting for
      sex, age, dominance of the study hand and respective baseline score. To identify potential
      predictive factors for long-term benefit after 80 mg methylprednisolone injection, surgery
      within 5 years will be analyzed according to the variables sex, age, dominance of the study
      hand, baseline symptom severity score (≥3 versus < 3) and baseline median nerve conduction
      abnormality (severe/moderate vs mild/normal).

      All statistical tests will be 2-sided and a p value of less than 0.05 will indicate
      statistical significance.
    

Intervention name(s): Methylprednisolone 80 mg; Methylprednisolone 40 mg; Saline
Intervention type(s): Drug; Drug; Other
Intervention description(s): 2 mL methylprednisolone (40 mg/mL) + 1 mL lidocaine; 1 mL methylprednisolone (40 mg/mL) + 1 mL saline + 1 mL lidocaine; 2 mL saline + 1 mL lidocaine
Other intervention name(s): Depo-Medrol; Depo-Medrol; Sodium chloride solution
Intervention MeSH terms: Methylprednisolone; Methylprednisolone Acetate; Methylprednisolone Hemisuccinate; Prednisolone; Prednisolone acetate; Prednisolone hemisuccinate; Prednisolone phosphate
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment