。
She fell off her bike and hurt her leg.
Literal
She [topic-は] bicycle [from-から] fell [then-て], leg [object-を] injured.
から marks the source of the falling — 'off / from.' The te-form 落ちて threads the two events together as cause and consequence ('fell off, and as a result injured'). 足 covers both 'leg' and 'foot' in Japanese — the same character lumps the whole lower limb under one word, and which English translation fits depends on context. 怪我する ('to get injured, to hurt oneself') is one of those Sino-Japanese-noun-plus-する verbs where the noun (怪我) and verb (する) can be split: 怪我をする (with optional を) is also common.