I had always thought injecting the TMJ laterally in upward direction would be best. A posterior approach was found more effective in the swine equivalent.
Comparison of Three Techniques for Swine Temporomandibular Joint Space Injection
Ding-Han Wang et al
J Oral Facial Pain Headache 2016;30:165–170. doi: 10.11607/ofph.1469
- Entering superior joint on TMJ
- inject almost vertical position except pointing 10 degrees up and 10 degrees to foreward
- verified by dissection of methylene blue injections
- Achieved 100% versus 33% by other techniques
Comment – they chose swine because of similarities to humans and make a case for posterior injection.