What kind of nursing diagnosis can I use for a patient that came in and has a complaint of "He states, "he went left and his knee twisted right with the ball" and he also states he felt a "pop" when it happened." "The pain is about a 5 out of 10."

One of admission nurse took some notes and noted that the patient has a Meniscal Tear and from the review of system " The patient's RLE unable to hyperextend, complaints of pain with extension, flexion to right when standing with support is 90* and painful. Upon completing McMurray test, a "click" is heard."

Which type of nursing diagnosis would be best for this patient? Acute Pain, Impaired Physical Mobility, or Deficient Knowledge?

I am leaning more towards to Impaired Physical Mobility. But the patient does have a pain of 5 out of 10. What would be the best choice?