You look it up in any good orthopedic reference book regarding hip surgery.
Things to consider: reason why hemi arthroplasty not total hip replacement (age, quality of hip joint OA). Surgery from which side: Posterior, Lateral or anterior (the latter is most unusual but can be done) Posterior problem Sciatic nerve and Gluts attachments, Lateral problem Gluts and Trochanter, Anterior femoral nerve and artery. Thus Muscle weakness and potential nerve damage are the main things.
By the way, the physiotherapy department ought to have reference books on this or the hospital library has. Dig in, ask you tutor where to find books what you learn now is a long never ending journey of learning.