Background De Quervain’s disease (dQD) is a stenosing tenosynovitis of the first compartment of the wrist, which is formed by the tendons of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB).There are two types of dQD. Type I dQD is characterized by a tight constriction of both tendons by a clear loop-shaped retinaculum with no evidence of septation between the two tendons. Type II dQD is characterized by an evident septation, and the retinaculum compresses only the EPB.Intra-sheath steroid injection is one of the best therapeutic approaches to dQD. However, in some cases (15–20%) it is not sufficiently effective. Intra-sheath injection failure is probably due to the presence of septation. We hypothesized that, in case of injection failure due to septation, a US-guided injection targeting the EPB might be effective.
Objectives We compared US-guided injection, targeting the EPB in dQDwith septation, to clinical injection.
Methods Forty-four wrists were randomly allocated to US-guided or manual (non-US-guided) injection. We conducted questionnaires related to subjective symptoms (wrist pain by 100 mm VAS) at baseline and 4 weeks after injection. All patients with worsening dQD disease activity at 4 weeks were allowed to switch to surgery (the patient’s choice).The primary outcome was a reduction in wrist pain (VAS) from baseline to 4 weeks in each group. The secondary outcome was the proportion of patients who switched to surgery within 6 weeks after injection in each group.
Results At 4 weeks, pain was significantly reduced in both groups. Pain on the 100 mm visual analogue scale (VAS) for the US group was 80.3 (SD 19.6) mm at baseline and 25.6 (SD 15.1) mm at 4 weeks after injection (p=0.004). Values for the manual group were 78.0 (SD 18.5) mm at baseline and 58.2 (SD 21.9) mm at 4 weeks after injection (p=0.04). Pain on the VAS showed a more significant decrease in the US-guided than in the manual injection group (p=0.0007) from baseline to 4 weeks after injection. Only two patients in the US group and nine in manual group required surgery. The ratio of surgeries to total number was significantly lower in the US than the manual group (p<0.01; Chi-square test).
Conclusions The results of this study suggest US-guided injection targeting the EPB in dQD patients with septation is more effective than manual injection.
Volpe A, Pavoni M, Marchetta A, et al. Ultrasound differentiation of two types of de Quervain’s disease: the role of retinaculum. Ann Rheum Dis. 2010, 69: 938–9.
Disclosure of Interest None Declared