S56.31 - Strain of extensor or abductor muscles, fascia and tendons of thumb at forearm level S56.3 - Injury of extensor or abductor muscles, fascia and tendons of thumb at forearm level S56.31 - Strain of extensor or abductor muscles, fascia and tendons of thumb at forearm level S56.311 - Strain of extensor or abductor muscles, fascia and tendons of right thumb at forearm level S56.312 - Strain of extensor or abductor muscles, fascia and tendons of left thumb at forearm level S56.319 - Strain of extensor or abductor muscles, fascia and tendons of unspecified thumb at forearm level