Complications

The principal complication of supracondylar fractures is injury to the brachial artery, which runs in close apposition to the site of this fracture. Damage to the artery can result in oedema in the forearm with compartment syndrome developing. Brachial artery injury is more common in completely displaced Gartland III (and IV) injuries. (1)

Other complications include:

Neurological Injury

• 11.3% incidence of traumatic neuropraxia. (2)
• anterior Interosseous nerve palsy: this is the most commonly injured nerve in extension-type supracondylar fractures.
• median nerve palsy: this can be traumatic or iatrogenic in origin.
• radial nerve palsy: this has been found to be more common in fractures with posteromedial displacement. (3)
• ulnar nerve palsy: this is the most commonly injured nerve in flexion-type fractures.

Compartment Syndrome

• this can result in the forearm from impaired perfusion in the setting of brachial artery injury and inadequate collateral circulation. (1)

Volkmann Ischaemic Contracture

• This is relatively rare.
• It can occur as a complication of forearm compartment syndrome and delayed treatment of arterial injury with resultant forearm ischemia. (1)

Malunion and Deformity

• Malunion can occur with resultant deformity in the sagittal, coronal and axial planes (which may result in the so-called ‘gunstock deformity’).
• Recurvatum deformity: the sagittal plane deformity is more likely to remodel in younger children because this is in the plane of movement of the elbow (flexion/extension). This is the most common sagittal plane deformity.
• Cubitus varus: coronal and axial plane deformity have minimal remodelling potential. Comminution of the medial column can cause collapse, malunion, and varus deformity. It may also occur because of a residual internal rotation deformity.
• Cubitus valgus: this can occur due to inadequate reduction and malunion. It can lead to tardy ulnar nerve palsy.

Stiffness

• The range of movement rapidly improves within the first six weeks following surgery and the range can improve to 98% of normal within the first 12 months. (4)
• Stiffness is more commonly associated with open reduction procedures. Long-term reduction in the range of movement is also associated with malunion. (5)

Pin-site infection

Pin-site migration

Reference

1. Blakey CM, Biant LC, Birch R. Ischaemia and the pink, pulseless hand complicating supracondylar fractures of the humerus in childhood: long-term follow-up. J Bone Joint Surg Br. 2009 Nov;91(11):1487-92.
2. Babal JC, Mehlman CT, Klein G. Nerve injuries associated with pediatric supracondylar humeral fractures: a meta-analysis. J Pediatr Orthop. 2010 Apr-May;30(3):253-63
3. Wang SI, Kwon TY, Hwang HP, Kim JR. Functional outcomes of Gartland III supracondylar humerus fractures with early neurovascular complications in children: A retrospective observational study. Medicine (Baltimore). 2017 Jun;96(25):e7148.
4. Zionts LE, Woodson CJ, Manjra N, Zalavras C. Time of return of elbow motion after percutaneous pinning of pediatric supracondylar humerus fractures. Clin Orthop Relat Res. 2009 Aug;467(8):2007-10.
5. Vaquero-Picado A, González-Morán G, Moraleda L. Management of supracondylar fractures of the humerus in children. EFORT Open Rev. 2018 Oct;3(10):526-540.