Elbow  Instability

Steve  Kronlage,  MD

Elbow  Dislocation

• 5.2  cases  per  100,000   people  in  US  per  yr.

• 26%  have  associated  fracture  Stonebach et.  al  JBJS 2012

• Simple• Complex

Elbow  Joint

• Not  a  “simple  hinge”• 2  degrees  of  freedom:• flexion-­‐extension• pronation-­‐supination• Tight  articulation• REQUIRES  Stability

Elbow  Stability

Primary  Stabilizers

• Ulno-­‐humeral   articulation• (Bones)• Anterior  Band  of  the  MCL• Lateral  Ligament  Complex

Secondary  Stabilizers• Radial  Head• Capsule• Common  Flexor  and  Extensor  Origins  

(Muscles)

Elbow  Stabilityanatomy

• Bones• Ligaments

Elbow  AnatomyBony  Stability

• 180º  of  motion  is  captured  between  the  trochlea  and  trochlear  notch

• Stabilizing  Columns1. Ant.medial  coronoid  facet  and  

the  medial  lip  of  trochlea2. Radial  head  and  capitellum

Pollock  et  al  J  Bone  Joint  Surg Am,  2009

Lateral  Collateral  Ligaments

• Radial  collateral  ligament• Lateral  ulnar  collateral        

ligamentPrimary  lateral  stabilizer

• Annular  ligamentradial  head

G  King

Medial  Collateral  Ligament

• Two  discrete  portions   of  the  ligament

• Neither  of  which  attach  to  the  humerus  at  the  point  of  rotation

• Anterior  Bundleligament   shapedTight  in  extension

• Posterior  BundleFan  shapedTight  in  Flexion

Elbow  Capsule

• Fibrous  sac  that  keeps  articular  fluid  within  the  joint

• The  capsule  allows  flow  of  synovial  fluid  from  the  anterior  to  posterior  compartments  (they  are  not  separate)

• Ligaments  are  very  tightly  associated  with  the  capsule,  often  thickenings

• Anterior  Capsule  is  important  in  stability

Elbow  InstabilityTYPES

• Simple• no  fracture,  most  common• Complex• multiple  types,  complex,  bony  injury

Simple  Dislocation

• Fall  on  outstretched  hand• Ligaments  tear,  elbow  hinges  out  of  joint

Schrieber,  et.al   J.  Hand  Surg 2013

Simple  Dislocation

• Valgus  stress  +  Supination   +  Axial  Load  during  flexion  =  PRLI• (posterior  rotatory  ligamentous   instability)• MCL  is  usually  torn  in  simple   dislocations• Patients  with  recurrent  dislocations   – LCL  is  always  torn

• Confusing• MCL  torn,  but  doesn’t   lead  to  problems• LUCL  torn  =  instability   if  not  healed

Schrieber,  et.al   J.  Hand  Surg 2013

Treatment  Simple  Elbow  Dislocation

• Can  usually  be  treated  with  closed  manipulation

• Done  in  flexion• “Pull”  olecranon  forward• Start  ROM  early• Depends   on  age  and  stability   after  

reduction• Older  earlier

Simple  Dislocationoutcomes

• Most  common  complication  is  loss  of  extension

• ROM  should  start  at  5-­‐7  days• Extension  is  limited  early  because  that  is  where  the  instability  occurs

• If  treated  restricted  motion,  most  likely  will  not  need  intervention

Complex  Elbow  Dislocations

•Elbow  Dislocation  plus:• Radial  head  fracture• Olecranon  fracture• Radial  head  and  coronoid  

(terrible  triad)

Complex  Elbow  Instability

1. Convert  to  simple  dislocations  by  resorting  bony  anatomy2. Initial  treatment  is  important3. Restoration  of  motion  results  from  restoration  of  a  congruent  

stable  jointEbrahimzadeh,  et  al  J  Hand  Surg 2010

Radial  Head  Fracture  with  Dislocation

• First  priority  is  to  reconstruct  radial  head

• *plates  and/or  screws,  more  commonly  replacement

• Fix  LCL  (will  be  torn  from  • humeral  epicondyle)• Move  early,  protected

Radial  head  fractures  and  ligaments

• Radial  head  fractures:  MRI  evaluation  of  associated  injuries• Itamura J1,  RoidisN,  Mirzayan R,  Vaishnav S,  Learch T,  Shean C.

• J  Shoulder  Elbow  Surg.  2005  Jul-­‐Aug;14(4):421-­‐4

• 24  patients  with  Mason  II  or  III  fractures• MRI• MCL  tear  55%• LCL  tear  80%

Elbow  Instability  with  olecranon   fracture

• Instability  usually  comes  through  the  olecranon  

• Olecranon  is  injured,  usually  sparing  the  ligaments  

• Fixation  of  the  olecranon  will  usually  grant  stability  to  the  elbow

• Often  will  have  radial  head  fractures

Terrible  Triad

• Elbow  dislocation• Radial  head  fracture• Coronoid  fracture

• *named  because   offrequent  problems  with  instability,   stiffness   and  degenerative   changes  

Terrible  Triadtreatment

• Repair  or  most  commonly  replacement  of  radial  head• Repair  coronoid• usually  through  drill  holes/suture  loop• Repair  LCL

• *if  still  unstable,  will  need  MCL  repair  or  hinged  external  fixator

Ebrahimzadeh,  et  al  J  Hand  Surg 2010

Terrible  Triad  rehab

• Depends  on  intra-­‐operative  stability• Early  motion  decreases  stiffness  but  can  increase  potential  instability

• Needs  careful  attention  and  frequent  radiographic  evaluation• Hinged  elbow  brace  slowly  increasing  extension

Fracture  SubluxationsVarus  Posteromedial  instability

• Results  from  anteromedial  facet  coronoid  fracture  in  addition  to  a  LCL  injury

• Can  result  in  persistent  instability  and  early  arthrosis

• Treated  with  buttress  plate  and  ligament  repair  

Ebrahimzadeh,  et  al  J  Hand  Surg 2010

Posterolateral  Rotatory  Instability

• The  LCL  complex  resists  varus  forces  (these  are  the  predominant  forces  on  the  elbow  during  ADLs)

• Chronic  injury  to  the  lateral  ligaments  causes  the  radial  head  to  subluxate  posteriorly  giving  symptoms  and  pain

Posterolateral  Rotatory  Instabilitysymptoms

• Lateral  elbow  pain• Weakness• May  have  had  surgery  for  lateral  epicondylitis• Pain  over  ligaments  (soft  spot)• May  have  mechanical  symptoms

Posterolateral  Rotatory  InstabilityExam

• Tenderness  over  lateral  elbow• May  have  lack  of  extension  due  

to  splinting• Chair  lift  off  test• “Pivot  Test” Odriscoll,  et  al  J  Bone  Joint  Surg Am,  2000  

Posterolateral  Rotatory  InstabilityImaging

• Radiographs  to  check  for  abnormalities  and  subluxations

• MRI  essential• Arthrogram  through  triceps  is  important

Treatment  PLRI

• The  injury  is  always  off  the  lateral  epicondyle• Initially  all  were  treated  with  free  graft  reconstruction• More  and  more  now  are  treated  with  direct  repair  of  ligaments  to  lateral  elbow

• Surgeons  choice  on  treatment• *I  use  graft  reconstruction  when  there  is  no  local  tissue  for  reconstruction  or  the  patient  has  excessive  ligamentous  laxity  (often  allograft)

Direct  Repair  for  Managing  Acute  and  Chronic  Lateral  Ulnar  Collateral  Ligament  Disruptions  

Dalunsiski,  Schrumpf,  Schreiber,  Nguyen,  Hotchkiss  J  Hand  Surg 2014;  39(6)  1125-­‐1129

• 34  patients• Compared  acute  vs  delayed  primary  repair• No  difference  in  outcome  between  groups• Can  do  primary  repair  of  ligaments  late

• Retrospective,  no  graft  patients  included  

Case  Example

• 42  year  old  female,  lateral  elbow  pain  after  a  fall• One  tennis  elbow  surgery• Second  surgery,  ATS  where  the  surgeon  debrided  an  area  of  synovitis  

around  the  lateral  ligaments• Normal  ROM,  pain  over  lateral  ligaments,  +    chair  lift  off  test• Normal  plain  films• MRI  consistent  with  lateral  ligament  disruption  and  lateral  epicondylitis

Chronic   Instability

• Challenging  problem• Multiple  techniques  describes  with  varying  results

Case  Example

• 39  year  old  female• Fracture  dislocation,  reduced  in  

ER,  dislocated  in  splint• Referred  in  after  9  weeks  of  

splinting• Very  little  motion

Elbow  InstabilityConclusion

• Simple  dislocation  do  well  with  guided  treatment  and  early  motion

• Radial  head  fractures  can  have  associated  LCL  injuries• MCL  torn  in  most  elbow  dislocations,  LCL  injury  gives  the  

symptoms• Complex  elbow  injuries  should  be  converted  to  simple  by  

stabilizing  bones• Early  recognition  and  treatment  of  injury  is  important

Thank  you