|
Year |
2005 |
|---|---|
|
Question Number |
52. |
|
Category |
Shoulder and Elbow |
Question
After surgical management of a terrible triad elbow injury, what position best provides stability against posterior subluxation?
1- Flexion with forearm supination
2- Flexion with forearm pronation
3- Extension with neutral forearm rotation
4- Extension with forearm supination
5- Extension with forearm pronation
Figures
Answer (click for answer)
PREFERRED RESPONSE: 2
Posterior dislocation of the elbow with associated fractures of the radial head and the coronoid process of the ulna has been referred to as the "terrible triad of the elbow". Subsequent posterolateral instability arises from disruption of the lateral collateral and annular ligaments. The lateral collateral ligament is an important stabilizer against varus and rotational instability. Forearm pronation stabilizes the lateral collateral ligament deficient elbow during flexion. These need to be treated surgically, and not with radial head excision alone. The cited article here showed that after sectioning the lateral ulnar collateral ligament, the radiocapitellar joint was most stable in pronation and flexion. Of note, most simple elbow dislocations tear both the medial and lateral ulnar collaterals, but don’t require surgery d/t intrinsic stability from osseous constraint.
Ring and Jupiter have a paper from JBJS 2002 which shows the dismal results associated with closed treatment of this injury, and treatment surgically without addressing both the radius fracture and coronoid fracture. 7/11 elbows dislocated in a splint, 5/11 dislocated after surgery, including all 4 treated with resection of the radial head. 7/11 had unsatisfactory results at final follow-up.
Reference: RECOMMENDED READINGS: Dunning CE, Zarzour ZD, Patterson SD, et al: Muscle forces and pronation stabilize the lateral ligament deficient elbow. Clin Orthop 2001;388:118-124.
Boyer MI, Galatz LM, Borelli J Jr, et al: Intra-articular fractures of the upper extremity: New concepts in surgical treatment. Instr Course Lect 2003;52:591-605.