MRI Monitoring of Disc Position Changes Following Botulinum Toxin Injection for Management of TMJ Clicking

Purpose: The aim of the present study is to investigate the effect of Botulinum Toxins-A (BTX-A) injection in the lateral pterygoid (LPM) muscle on disc position in cases of TMJ clicking. Patients and methods: This study enrolled 6 patients with total of I I joints, all patients fulfilled stages I II in Wilke s classification proved by MRI of the TMJs. BTX-A injected in the ipsilateral LPM muscle with the guidance of EMG (electromyogram). Patients were assessed clinically over 4 months. And by MRI after 3 months. Results: Ten out of eleven joints showed disappearance of clicking immediately post injection till the end of the 4 months follow-up period The 3 months MRI showed marked improvement in disc position. Conclusion: Injection in the LPM muscle lead to disappearance of joint clicking and significant improvement in disc position as proven by MRI.