A quick question on occlusion

[Qnesp]

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Hello everyone. I'm new here and wish to be an active member on the forums, I've been reading a lot of your postings and they've been really helpful. I'm an international student that's here to apply for a residency, but before so I'm studying for my boards, and there's this question that has been really bugging me, and no matter how much I searched on the Internet, I couldn't come up with an answer. So I figured this would be the right place. Anyways, the question is as follows:


A patient comes to your clinic presenting with a TMJ problem, and when asked to open his mouth, it deviates to the left side. Where exactly is the problem in this case?

1. Left side translation of the condyle
2. Left side rotation of the condyle


I'd really like it if you could help me answer this with a brief explanation. Thank you.

Edit:
My answer was left rotation because from what I understood, since the patient tried to open and it didn't? Then that means that the condyles and their disc did not move at all. But could it be that they rotated to their terminal hinge axis and failed to continue translation on the eminence?

 

[Saddleshoes]

If you palpate the condyles (bilaterally) as the patient opens I think you will find your answer.

 

[DaleDoback]

Hello everyone. I'm new here and wish to be an active member on the forums, I've been reading a lot of your postings and they've been really helpful. I'm an international student that's here to apply for a residency, but before so I'm studying for my boards, and there's this question that has been really bugging me, and no matter how much I searched on the Internet, I couldn't come up with an answer. So I figured this would be the right place. Anyways, the question is as follows:


A patient comes to your clinic presenting with a TMJ problem, and when asked to open his mouth, it deviates to the left side. Where exactly is the problem in this case?

1. Left side translation of the condyle
2. Left side rotation of the condyle


I'd really like it if you could help me answer this with a brief explanation. Thank you.

Edit:
My answer was left rotation because from what I understood, since the patient tried to open and it didn't? Then that means that the condyles and their disc did not move at all. But could it be that they rotated to their terminal hinge axis and failed to continue translation on the eminence?

Left side translation issue. I see it weekly in patients with a nonreducing articular disc. The right condylar head is translating down and the left condyle doesn't, which leads to the deviation to the affected side.

If it was a true rotation issue, the condyle would be ankylosed. If the case is severe enough, the patient wouldn't even deviate because they wouldn't open wide enough to even translate on the right.

 

[Qnesp]

Left side translation issue. I see it weekly in patients with a nonreducing articular disc. The right condylar head is translating down and the left condyle doesn't, which leads to the deviation to the affected side.

If it was a true rotation issue, the condyle would be ankylosed. If the case is severe enough, the patient wouldn't even deviate because they wouldn't open wide enough to even translate on the right.

Thank you very much. It could get hard to visualize such concepts, specially one that's as complex as the TMJ, by merely reading them off of a book.

Thanks again.