RT Book, Section
A1 Breed, Meghan
A1 Fitch, Robert Warne
A2 Knoop, Kevin J.
A2 Stack, Lawrence B.
A2 Storrow, Alan B.
A2 Thurman, R. Jason
SR Print(0)
ID 1181042120
T1 Knee Dislocation
T2 The Atlas of Emergency Medicine, 5e
YR 2021
FD 2021
PB McGraw-Hill
PP New York, NY
SN 9781260134940
LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1181042120
RD 2024/04/23
AB Knee  dislocations  are  classified  by  tibial  displacement  relative  to  the  femur  (anterior,  posterior,  medial,  lateral,  or  rotatory).  They  invariably  cause  multiple  ligamentous  injuries  and  are  usually  the  result  of  motor  vehicle  collisions,  falls,  sports,  and  industrial  injuries.  Anterior  dislocations  are  more  common  and  usually  occur  after  high-energy  hyperextension  injuries.  Knee  dislocations  are  associated  with  popliteal  artery  and  common  peroneal  and  tibial  nerve  injuries.  Popliteal  artery  injury  can  result  from  both  anterior  and  posterior  dislocations  and  is  more  common  than  nerve  injury.  Injury  can  be  present  despite  normal  pulses,  and  if  not  identified  and  repaired  within  8  hours,  amputation  may  be  necessary.  Common  peroneal  nerve  injury  can  cause  decreased  sensation  on  the  lateral  foot,  impaired  dorsiflexion  and  eversion,  and  impaired  sensation  over  the  1st  dorsal  web  space.  Knee  dislocations  can  spontaneously  relocate,  so  the  physician  must  maintain  a  high  index  of  suspicion.  Injuries  are  painful  and  visually  striking.  An  effusion  will  often  be  absent  since  the  capsule  has  been  violated.  On  exam,  the  knee  will  be  grossly  unstable  since  dislocations  tend  to  injure  most  of  the  surrounding  ligaments.