I don't remember, but only, only a fractured collarbone, which I recommend to anyone that needs to break a bone, break a collarbone.
( ( ( ( ( I ( ( do n't ) remember ) ) , ) but ) ( only ( , ( ( ( ( ( only ( a ( fractured collarbone ) ) ) , ) ( which ( I ( recommend ( to ( anyone ( that ( needs ( to ( break ( a bone ) ) ) ) ) ) ) ) ) ) ) , ) ( break ( a collarbone ) ) ) ) ) ) . )
(ROOT (S (S (NP (PRP I)) (VP (VBP do) (RB n't) (VP (VB remember)))) (, ,) (CC but) (S (ADVP (RB only)) (, ,) (NP (NP (RB only) (DT a) (JJ fractured) (NN collarbone)) (, ,) (SBAR (WHNP (WDT which)) (S (NP (PRP I)) (VP (VBP recommend) (PP (TO to) (NP (NP (NN anyone)) (SBAR (WHNP (WDT that)) (S (VP (VBZ needs) (S (VP (TO to) (VP (VB break) (NP (DT a) (NN bone))))))))))))) (, ,)) (VP (VBP break) (NP (DT a) (NN collarbone)))) (. .)))
The collarbone is the best bone to break. 
( ( The collarbone ) ( ( is ( ( the ( best bone ) ) ( to break ) ) ) . ) )
(ROOT (S (NP (DT The) (NN collarbone)) (VP (VBZ is) (NP (NP (DT the) (JJS best) (NN bone)) (SBAR (S (VP (TO to) (VP (VB break))))))) (. .)))