Brief Answer:
Both are different entities

Detailed Answer:
Hi,

Thank you for posting the question.

MUA (Manipulation Under Anesthesia)- means a surgeon performs some external manouvers over the affected body part by pulling,pushing,rotating,applying traction etc. Usually this is the first step before actual surgery is performed.

Internal fixation- means insertion of steel / titanium implants inside the bone to fix the fracture. (This can be either by open or closed methods).

ORIF (Open Reduction Internal fixation) - This is done during the actual operation. Once the fractured part is exposed,the surgeon manipulates the displaced bones directly before fixing with implants).

DHS (Dynamic Hip Screw) - a special type of implant used specially for fixing hip bone fractures).

MUA/Internal fixation is performed for minimally displaced fractures in hip with cancellos cannulated screws (e.g.- fracture neck of femur)

ORIF/DHS is performed for intertrochanteric fractures of the hip by using a lag screw and a supporting plate.

So,in conclusion- MUA/Internal fixation is totally different from ORIF/DHS.

Thank you.

Let me know if you have any other questions.

Thanks

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