▁of ▁the ▁caps ule ▁of ▁the ▁shoulder - joint . ▁ ▁Inner v ation ▁The ▁mus cle ▁is ▁inner v ated ▁by ▁the ▁posterior ▁branch ▁of ▁ax ill ary ▁n erve ▁where ▁it ▁forms ▁a ▁pseud og ang l ion . ▁A ▁pseud og ang l ion ▁has ▁no ▁n erve ▁cells ▁but ▁n erve ▁fib res ▁are ▁present . ▁Dam age ▁to ▁the ▁fib ers ▁inner v ating ▁the ▁ter es ▁minor ▁is ▁clin ically ▁significant . ▁ ▁Vari ation ▁Sometimes ▁a ▁group ▁of ▁mus cle ▁fib res ▁from ▁ter es ▁minor ▁may ▁be ▁f used ▁with ▁in fr asp in atus . ▁ ▁Function ▁The ▁in fr asp in atus ▁and ▁ter es ▁minor ▁attach ▁to ▁head ▁of ▁the ▁hum er us ; ▁as ▁part ▁of ▁the ▁rot ator ▁cu ff ▁they ▁help ▁hold ▁the ▁hum eral ▁head ▁in ▁the ▁g len oid ▁cav ity ▁of ▁the ▁sc ap ula . ▁They ▁work ▁in ▁tan dem ▁with ▁the ▁posterior ▁del to id ▁to ▁extern ally ▁( l ater ally ) ▁rotate ▁the ▁hum er us , ▁as ▁well ▁as ▁ad du ction . ▁Ter es ▁Minor ▁can ▁produce ▁only ▁very ▁small ▁sc ap ular ▁plane ▁ad du ction ▁during ▁maximal ▁contra ction ▁( H ugh es ▁RE , ▁An ▁K N ▁ 1 9 9 6 ) ▁with ▁ad duct or ▁moment ▁arm ▁of ▁approximately ▁ 0 . 2 ▁cm ▁at ▁ 4 5 ° ▁of ▁shoulder ▁internal ▁rotation ▁and ▁approximately ▁ 0 . 1 ▁cm ▁at ▁ 4 5 °