Is this slipped capital femoral epiphysis usually treated with surgery or bracing?   Yes, in almost all cases these patients need to be taken to the operating room for percutaneous fixation.

Name the different stress fracture locations that are thought to be high risk and require management other than rest..   These include femoral neck, anterior tibial diaphysis, medial malleolus, talus, navicular, seasmoid, and proximal 5th metatarsal.  The management of these typically include either non-weight bearing with boot or surgical fixation.   Referenced from Brukner and

If ECG is concerning for this diagnosis, which is the next best test to order?   If the ECG is concerning for HCM, you would obtain an echo to confirm the diagnosis.

What findings do you expect on ECG?   Since one of the pathological findings of hypertrophic cardiomyopathy is left ventricular thickening you would expect to see signs of LVH on ECG.  These include nonspecific T wave and ST segment abnormalities, Q wave in the lateral or inferior leads, and left axis deviation,