[Effect of needle-knife release on the median nerve and transverse carpal ligament in rabbits with carpal tunnel syndrome].

OBJECTIVES: To investigate the effect of needle knife release on median nerve (MN) and transverse carpal ligament (TCL) morphology and function and expression levels of inflammatory factors in rabbit models of carpal tunnel syndrome (CTS). Methods Thirty adult New Zealand rabbits were randomized equally into control group, CTS model group, ultrasound-guided needle knife release group, needle knife release group without ultrasound guidance, and sham treatment groups. In all but the control group, the rabbits were subjected to CTS modeling by 10% glucose solution injection into the carpal tunnel once a week for 4 consecutive weeks, followed by interventions with a single treatment session. At 3 days and 30 days after the interventions, 3 rabbits from each group were selected for ultrasound measurement of TCL and MN thickness, electrophysiological testing, ultrasound elastography, and inflammatory cytokine level assessment. RESULTS: In the rabbit models of CTS, ultrasound-guided needle knife release significantly reduced the thickness of TCL and MN and improved sensory nerve conduction velocity at both 3 and 30 days after the intervention. Elastography of the TCL showed markedly softened intra-carpal tissues after ultrasound-guided needle knife release and achieved superior outcomes over those in the other groups. The treatment also significantly reduced IL-17 levels and lowered IL-6 and PGE2 expression at 30 days after the intervention. CONCLUSIONS: Needle knife release of the TCL reduces thickness of the MN and TCL, enhances median nerve function, alleviates intrascatic tissue stiffness, and downregulates inflammatory factors in the carpal tunnel in rabbit models of CTS, and ultrasound guidance further enhances its therapeutic efficacy.