Type I Radial Head Fracture (based on Mason classification)
- fissure or margin sector fracture w/ displacement less than 2 mm;
- type I fractures may be difficult to identify;
- fat pads are intracapsular but extrasynovial;
- anterior fat pad is normally visible anterioir to coronoid fossa;
- posterior fat pad sign is pathologic & should suggest need for further
oblique views, including radial head capitellum view;
- there is no mechanical block to motion;
- type I frx are nondisplaced & may be missed on routine radiographs;
- posterior fat pad sign is pathologic & should suggest further oblique views,
including radial head-capitellum (RHC) view.
- radial head frx is most common type of elbow fracture in adults (radial neck in kids)
- Fall on outstretched hand.... head into capitulum
- the high frequency of frx in the anterolateral aspect of radial head occurs as a result of lack of subchondral bone under anterolaterl aspect of the radial head;
- because the anterolateral aspect of radial head does not articulate w/ sigmoid fossa, frx in the region are amenable to fixation w/ small screws;
- associated injuries:
- frx of the capitellum
- distal radius frx
- dislocation of the distal RU joint (Essex Lopresti Fracture)
- valgus instability (MCL rupture)
- probably more common than is reported;
- indications for repair of the MCL will be determined based on stability of the elbow thru a functional range of motion;
- rupture of the triceps tendon
- elbow dislocation:
- terrible triad: RHF + MCL + coronoid process frx;
Dx and Exam:
- pain, effusion in the elbow, & tenderness on palpation directly over radial head are typical manifestations;
- if frx is displaced, click or crepitus over radial head is detected w/ supination;
- if elbow ROM is limited, then aspirate and inject several cc of lidocaine, and then re-examine;
- check for blocks to flexion-extension as well as supination-pronation;
- wrist tenderness with ROM is common
Treatment: (based on Mason classification)
- type I
- type II
- less than 30% of radial head;
- more than 2 mm displacement
- type III - entire radial head fractured A,B and C
- ORIF of radial head fracture
- excision of radial head:
- Posterolateral Rotatory Instability of the Elbow Following Radial Head Resection.
- The Effect of Radial Head Excision and Arthroplasty on Elbow Kinematics and Stability.
- radial head implants:
- Treatment of displaced segmental radial-head fractures. Long-term follow-up.
- complex fractures
- radial head frx & elbow dislocation :
- radial head frx & MCL instability :
- Essex Lopresti Fracture
- Radial head fractures and their effect on the distal radioulnar joint. A rationale for treatment.
- Radial head fracture. A potentially complex injury.
- Radial head fractures with acute distal radioulnar dislocation.