Digital extensor expansion

Question 1

What is the course of Extensor digitorum tendons?

Answer 1

cross over MP joint and 1st IP joint to terminate on the base of the middle phalanx
through the extensions on the lateral band it also connects with base of distal phalanx

Question 2

What is the Extensor hood (extensor expansion, sagital band)?

Answer 2

triangular shaped aperberosis that is widest overlying the MP joint and borrowing as it projects distally
joins the the interosseus /lumbricals tendons with extensor tendons
joins the lateral band of the extensor digitorum tendons

Question 3

What are the lateral bands?

Answer 3

tendinous bands with a muscular attachments from interosseus and lumbrical muscles which cross to the palmar side of the MP joints and sense tendons into the extensor digitorum as it approaches the base of the middle phalanx. they continue on to cross the 2nd IP joint dorsally to end at the base of the distal phalanx on the dorsal surface