HPI:  Middle age male who presents after falling at work. His medial forearm stroke a metal bucket just distal to his elbow and resulted in a large laceration.

PE: Patient is unable to flex at the DIP of digit 4 and 5. He is unable to cross the second and third fingers or adduct his fingers. He has decreased sensation over the medial aspect of the 4th and 5th digit.  Suspected ulnar nerve laceration. 

Innervation:
-   Motor:

• Flexor carpi ulnaris and Flexor digitorum profundus for the 4th and 5th digits.
• Adductor pollicis and deep head of flexor pollicis brevis
• Interossei and 3rd and 4th lumbricals. 
• Abductor digiti minimi, opponens digiti minimi, flexor digiti minimi. 
  

-    Sensory:

•  Dorsal and palmar cutaneous branches as well as Superficial terminal branches. 
  

Clinical conditions:

•  Distal humerus fracture
  
•  External compression at the medial epicondyle
  
•  Prolonged elbow flexion. 
  
•  Medial epicondylitis (Golfer’s elbow)
  
•  Compression in Guyon’s canal (spares 4th and 5th digit flexion)
  
•  Propulsion of a wheelchair
  
•  Fractures of the hook of the hamate
  

Treatment: Forearm exploration with transected nerve repair.

Pearls:

•  Evaluate flexion at the DIP of the 4th and 5th digits. 
  
•  Inablity to adduct the fingers. Crossing the 2nd and 3rd digit is maximum adduction. If unable to do this secondary to pain, can adduct 2nd and 3rd digit in “scissoring” motion against examiners fingers between the medial aspect of 2nd digit and lateral aspect of 3rd digit.  
  
•  Decreased sensation at the lateral 4th and entire 5th digit. 
  
•  Compression in Guyon’s canal will exhibit decreased sensation and inability to adduct the fingers. Flexion of 4th and 5th digit is spared.
  

 

AP showing mild varus angulation    

Lateral film showing significant posterior displacement of distal portion of fracture

Supracondylar Humerus Fractures:
Two categories:
·       Extension: Distal fragment displaced anteriorly (95% of cases).
·       Flexion: Distal fragment displaced posteriorly (5% of cases).

Four Types:
·       I: Nondisplaced: look for posterior fat pad
·       II: Displaced. Posterior cortex intact
·       III: Completely displaced
·       IV: Complete periosteal disruption with instability on flexion and extension.

Presentation:

·       Usually from fall on outstretched hand.
·       Frequently will have neurologic findings:
·       Anterior Interosseus Neuropraxia:
·       Most common neurologic finding. Particularly with extension-type fractures.
·       AIN is a branch of Median nerve.
·       Patient's cannot flex thumb IP joint or index DIP joint (Can't make an “OK” sign).
        Almost all will resolve with conservative management.

       Also have vascular compromise in approximately 1%
       Usually brachial artery compromise
       High collateral flow, so patient may have a pink, but pulseless extremity. Still requires emergent reduction.

Treatment:
       Type I: Immobilization at 90 degrees and ortho follow-up.
       Type II: Closed reduction unless displacement is minimal.
       Adequate reduction: Baumann's angle wnl, anterior humeral line transects capitellum
       Type III: High-risk for neurovascular complications. Get ortho involved. Almost always require closed reduction + pinning vs. open reduction
     Type IV: Open surgical reduction and fixation

       Indications for open reduction:
       1.) Inadequate reduction with closed techniques
       2.) Vascular injury
       3.) open fracture
       4.) Type iv fracture

HPI:  Patient presents with a grossly deformed right upper extremity.

PE:  Gross deformity of humerus, no open fracture.  Unable to extend wrist. Unable to hyper-extend MP joints of fingers and unable to flex IP joint of thumb.  Radial and ulnar pulses intact.

IMAGING:  Multi-factorial fracture along the mid third of humerus along the expected course of the radial nerve.

DISPO (if at free standing ED):  Transfer patient to ED with on-call orthopedics for definitive fixation.  Reduce and splint prior to transfer.

TREATMENT:  Nonoperative managment.  Splinted and cast at bedside.  Follow radial nerve palsy clinically for improvement.