Background Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Ultrasound guided hydrodissection (UGH) of median nerve is a new method of treatment of CTS¹. Ultrasonography (US) has the ability to determine the effectiveness of various treatment modalities in CTS².

Objectives To test the safety and efficacy of UGH of median nerve as a new method of treatment of idiopathic CTS.

Methods Sixty five consecutive cases of idiopathic carpal tunnel syndrome (in 45 patients) diagnosed by motor & sensory median nerve conduction studies and by US measurement of cross-sectional area (CSA) of the median nerve measured at the tunnel inlet. Patients were grouped according to CSA into 3 groups: mild(CSA10-13mm²), moderate (CSA: □13-15mm²) and sever (CSA □ 15 mm²). All patients underwent UGH of median nerve with 10 ml of normal saline (9% Nacl) using a 25-gauge needle. After hydrodissection, a series of about 100 perforations of the flexor retinaculum was made using ultrasound to visualize the needle tip to insure that the tip perforated the retinaculum on each pass, and did not contact the median nerve. At the end of the procedure, 40 mg of triamcinolone acetonide was injected. Tingling & numbness during day (DTN) and night (NTN) graded on a visual analogue scale (0-10) were determined on the initial (W0) and 6 months after treatment (W24). Sonographic CSA of the median nerve was determined at (W0) and (W24). Any post procedure complications were reported.

Results There was a significant reduction in Tingling & numbness during day (DTN) (mean value± SD) between W0 (6.87± 1.1) and W24 (1.15 ± 0.9) p< 0.001. Night tingling and numbness reduced significantly between W0 (7.18 ± 1.2) and W24 (1.3±0.4) p< 0.001. only 4 (7.3%) cases reported no improvement at W24. Sonographic CSA of the median nerve reduced significantly between W0 (16 ± 5.7) and W24 (12.5±4.4) p< 0.001. While at W0 classification of groups according to sonographic CSA was as follow: 21 (33.3%) mild cases, 15 (23.8%) moderate cases and 27(42.9%) severe cases, at W24: 46.7% of cases in mild group, 13% of cases in moderate group and 7.4% of cases in severe group (22.2% of cases in all groups) reclassified sonographically as normal cases. 9 cases (14.3%) did not come for follow up.

Safety:10(15.9%) cases reported pain at needle site that resolved 2 weeks after the procedure.

Conclusions Hydrodissection of median nerve is a safe and effective procedure in management of idiopathic CTS. To the best of our knowledge this the first study to detect the effect of hydrodissection of median nerve by US in cases of CTS.

References

1. Malone GD, Clark BT and Wei N. Ultrasound-guided percutaneous injection, hydrodissection, and fenestration for carpal tunnel syndrome: description of a new technique. Journal of Applied Research. 2010. Mar; 10 (3): 116-123

2. Soyupek F, Soyupek A, Kutluhan S, et al. Determining the effectiveness of various treatment modalities in carpal tunnel syndrome by ultrasonography and comparing ultrasonographic findings with other outcomes. Rheumatol Int. 2012 Oct;32(10):3229-34.

References

Disclosure of Interest None Declared