When  the  arm  is  involved,  there  is  always  unequal  spasm  in  the  two  sides
of  the  neck.  The  sterno-mastoid  that  is  most  affected  may  be  on  the  same
side  as  the  arm,  or  on  the  opposite  side.  In  the  cases  that  I  have  seen  in
which  the  arm  was  affected  after  the  neck,  it  was  the  arm  on  the  side  opposite
to  the  most  affected  sterno-mastoid.  When  the  arm  is  affected  first,  either
sterno-mastoid  may  be  the  seat  of  the  chief  spasm,  and  the  head  may  thus
be  turned  from,  or  inclined  toward,  the  arm  that  is  affected.  In  one  case  of
clonic  spasm  in  the  right  sterno-mastoid  there  was  also  spasm  in  the  left  del-
toid, but  in  no  other  muscle.  Another  instance  of  this  relation  is  presented
by  the  patient  shown  in  Fig.  322.  In  him  the  spasm  commenced  in  the
arm  and  spread  to  the  neck,  where  it  involved  the  right  sterno-mastoid,  the
left  trapezius  and  splenius,  and  the  right  platysma.  It  became  continuous  in
both  arm  and  neck,  so  that  the  upper  arm  was  in  constant  strong  abduction,
and  the  forearm  was  carried  in  front  of  the  body,  while  the  face  was  turned
toward  the  shoulder.
Considerable  spasm  always  occasions  discomfort  to  the  patient,  partly  due
to  fatigue  in  the  muscles.    There  is  not  commonly  any  actual  cramp-like  pain


1022


WRY-NECK.
