I was 4 days into a 7 day hike in the backcountry of New Zealand with 3 friends when i slipped and tore a medial ligament in my knee. I tried anti inflammatories overnight but the swelling did not go down and I was incapable of walking for 3 days through reasonably rugged and slippery country to get out. So having discussed it the night before and reassessed the injury the following morning we decided the best thing was to activate the PLB – especially as there was a space in front of the hut a helicopter could land – but most of the rest of the terrain we would be hiking through the next days would require me to be winched up if i tried to keep going but couldnt.