One of these muscle strains is not like the others, out of hamstring quadriceps, calf and groin. Read through this short thread to find out which from our latest @BJSM_BMJ paper.....
But pre-poll (no peeking below) which of the “Big 4” has the most differences from the other 3 from an Epidemiology perspective? [be brave and have a guess....]
....if you answered “groin” it was the best incorrect answer, as you can argue that diagnostically it is the least pure and therefore perhaps the most polluted dataset of the 4. But actually the correct answer is “Calf strains” - behave differently from the others
First difference: calf strains have age as an independent risk factor (once past history has been accounted for). Age is not a risk factor for the other three
Second difference: for the other three, the log decay curve for recurrence by week is very tight. Each week is safer (for recurrence) than the week before. Calf strains get fewer early recurrences than the others but more late recurrences
Third difference: in recent years (which for AFL means interchange restrictions and for all codes means better GPS monitoring) the rates of the other muscle strains are decreasing but the rates of calf strains are increasing
Even though in theory the groin strain diagnosis category may be fuzzy, the Epi data for AFL suggests that they behave very similarly after return to play to hamstring strains and quadriceps strains. Perhaps diagnosis is cleaner than we thought for groin muscular strains
For all 4 though, recent history followed by past history of the same muscle strain dwarfed all other risk factors by a very large margin. The most important muscle strain to prevent, if possible, is the first one ☝️
@threadreaderapp unroll please
