Supracondylar Humerus Fracture and Compartment Syndrome

Incidence: average of 32 cases annually in US in 2002 report,[1] little subsequent change.

Avoid

Closed reduction and casting. “Closed reduction and casting also has a higher risk of Volkmann ischemic contracture than treatment with early pinning.”[2] Eight out of 10 patients with supracondylar humerus fractures who developed compartment syndrome and ischemic contractures in a 1979 series had undergone attempts at closed reduction and immobilization.[3]
Tight bandages to an injured extremity. The originally described cause of Volkmann’s ischemic contracture of the forearm.[4]
Elbow hyperflexion of 90° or more, and likely 70° or more, decreases vascular flow and contributes to ischemia, especially with anterior metaphyseal fracture spike. “Because of the risk of ischemia, most authors now recommend that hyperflexion of the elbow should be avoided after operative fixation [or after splinting].”[5]

Other Risk Factors
Vascular injury. “Patients presenting with a pulseless and poorly perfused hand have nearly a 50% chance of requiring vascular surgery and nearly 25% chance of developing compartment syndrome.”[6]
Reperfusion injury. “A further contributing factor to compartment syndrome in both patients with post-operative changes in the radial pulse (patients 1 and 2) could have been an ischemia reperfusion injury following correction of the initial vascular deficit. Reperfusion after treatment for arterial obstruction is a well-known cause of compartment syndrome. The reperfusion syndrome consists of a local response with limb swelling, an associated inflammatory response and a possible systemic response, resulting in skeletal myonecrosis (occurring between three to six hours after reperfusion).”[7]

Confounding Factors
Median nerve palsy can mask pain and contribute to a “silent compartment syndrome.”[8] “The clinical diagnosis of compartment syndrome may have been more difficult in the post-operative period because of the presence of a neurological deficit masking the symptoms and signs, in particular a median nerve palsy, as seen in four patients.”[9] “Open injuries and fractures associated with nerve injury are at higher rates of developing a compartment syndrome; in the later instance, the associated nerve injury presumably masks the clinical signs and symptoms of compartment syndrome.”[10]

Warning Signs
“Three A’s of Pediatric Compartment Syndrome: agitation, anxiety and increasing analgesic requirement which often precede the classic presentation by several hours.”[11] “An increasing analgesic requirement, in combination with other clinical signs, however, was a more sensitive indicator of compartment syndrome…”[12]
Excessive elbow swelling. “The fact that ten of 11 patients [with compartment syndrome] were recorded as having severe swelling at presentation is noteworthy. We feel that severe elbow swelling (with or without ecchymosis) should alert the clinician to a high index of suspicion for the possibility of compartment syndrome, particularly when there has been a delay in reduction of the fracture."[13] “In our opinion, supracondylar fractures presenting with excessive swelling should be considered at increased risk of developing a compartment syndrome if treatment is delayed."[14]
“Paralysis…may be present only after irreversible damage has already occurred.”[15]

Outcomes
Irreversible muscle damage can occur with as little as four hours of ischemia time. “Untreated ACS [acute compartment syndrome] leads to irreversible muscle damage beginning approximately 4 hours from the onset of elevated pressure.” Even for mild-mechanism non-fracture compartment syndromes, 54% had myonecrosis at surgery and 31% had permanent neurologic or functional deficit even with surgery within 48 hours.[16]
Poor outcomes with irreversible loss of function for most children with compartment syndrome after supracondylar humerus fractures, even with fasciotomies within 24-48 hours. “Severe contracture still developed in patients with supracondylar humerus fractures treated with fasciotomy within 48 hours.”[17] In Ramachandran’s series, all patients with supracondylar humerus fractures who developed compartment syndrome had permanent deficits [five severe, one moderate, five mild], notwithstanding fasciotomy within 48 hours in all but two. [18]

Best Practices
In addition to early treatment and close monitoring when symptoms arise, proactive preventive measures to mitigate risk factors may be considered.
Elbow should be splinted in a position of comfort, less than 90° of flexion and likely less than 70°.[19]
Avoid closed reduction of displaced fractures in ER and pin displaced fractures early. “Secondary damage to a peripheral nerve may result from manipulation of the fracture or hyperflexion of the swollen elbow as part of conservative management. The consequences to the circulation of flexing an already tense elbow have been described by Charnley as being similar to the kinking of a distended balloon.”[20]
Regular neurovascular checks by MD or trained nursing staff with notification orders.
Instruct referring providers at transferring facilities to (1) avoid any closed reduction attempt, (2) splint in position of comfort with less than 70° of elbow flexion, (3) ensure wraps are loosely applied and not tight, and (4) to perform regular neurovascular checks.
Pin fractures with absent pulse or major nerve palsy emergently. “In the ‘pink, pulseless hand’, a concurrent nerve palsy prompts early exploration as it is strongly predictive of nerve and vessel entrapment.”[21] “In our practice, children with absent pulse or nerve palsy are taken for reduction and pinning in an expedited manner. Cases with less severe injury are treated in an urgent manner during daylight hours.”[22]
Inpatient monitoring of patient with pink, pulseless hand for 24-48 hours after pinning. “Until further information is available it would be reasonable to monitor carefully a pink, pulseless hand over the ensuing 24 to 48 hours after satisfactory reduction and pinning of the fracture. If perfusion of the hand deteriorates during this time, the pain worsens and there are signs of a deteriorating neurological picture, exploration of the brachial artery and the affected nerve(s) is indicated."[23]

References

[1] Battaglia TC, Armstrong DG, Schwend RM. Battaglia TC, Armstrong DG, Schwend RM. Factors affecting forearm compartment pressures in children with supracondylar fractures of the humerus. J Pediatr Orthop. 2002;22(4):431-439.

[2] Morrissy, Raymond T. and Stuart L. Weinstein, eds. Lovell and Winter’s Pediatric Orthopedics, Seventh Edition, Philadelphia (2006): Lippincott Williams and Wilkins, 1710.

[3] Mubarak SJ, Carroll NC. Volkmann's contracture in children: aetiology and prevention. J Bone Joint Surg Br. 1979;61-B(3):285-293. doi:10.1302/0301-620X.61B3.479251.

[4] von Volkmann R. Ischaemic muscle paralyses and contractures. 1881. Clin Orthop Relat Res. 2007;456:20-21. doi:10.1097/BLO.0b013e318032561f

[5] Ramachandran M, Skaggs DL, Crawford HA, et al. Delaying treatment of supracondylar fractures in children. Has the Pendulum Swung Too Far? Journal of Bone and Joint Surgery Br Vol. 90-B, No. 9, Sep 2008, 1228-1233.

[6] Lovell and Winter 2006 [ibid] 1719.

[7] Ramachandran 2008 [ibid].

[8] Frei B, Sommer-Joergensen V, Holland-Cunz S, Mayr J. Acute compartment syndrome in children; beware of "silent" compartment syndrome: A CARE-compliant case report. Medicine (Baltimore). 2020;99(23):e20504. doi:10.1097/MD.0000000000020504

[9] Ramachandran 2008 [ibid], 1232.

[10] Noonan and McCarthy 2010 [ibid].

[11] Noonan, KJ, McCarthy, JJ. Compartment Syndromes in the Pediatric Patient. J Pediatr Orthop, 2010;30(3):S96-S101. doi: 10.1097/BPO.0b013e3181d07118

[12] Bae et al 2001 [ibid].

[13] Ramachandran et al 2008 [ibid].

[14] Garg S, Weller A, Larson AN, et al. Clinical characteristics of severe supracondylar humerus fractures in children. J Pediatr Orthop. 2014;34(1):34-39. doi:10.1097/BPO.0b013e31829c0046.

[15] Bae DS, Kadiyala RK, Waters PM. Acute compartment syndrome in children: contemporary diagnosis, treatment, and outcome. J Pediatr Orthop. 2001;21(5):680-688.

[16] Livingston K, Glotzbecker M, Miller PE, Hresko MT, Hedequist D, Shore BJ. Pediatric Nonfracture Acute Compartment Syndrome: A Review of 39 Cases. J Pediatr Orthop. 2016;36(7):685-690. doi:10.1097/BPO.0000000000000526.

[17] Mubarak and Carroll [ibid] 1979.

[18] Ramachandran et al 2008 [ibid].

[19] AAOS Appropriate Use Criteria for the Management of Pediatric Supracondylar Humerus Fractures. Adopted by the American Academy of Orthopaedic Surgeons Board of Directors, September 5, 2014.

[20] Robb JE. The pink, pulseless hand after supracondylar fracture of the humerus in children. J Bone Joint Surg Br. 2009;91(11):1410-1412. doi:10.1302/0301-620X.91B11.23349.

[21] Kwok IH, Silk ZM, Quick TJ, Sinisi M, MacQuillan A, Fox M. Nerve injuries associated with supracondylar fractures of the humerus in children: our experience in a specialist peripheral nerve injury unit. Bone Joint J. 2016;98-B(6):851-856. doi:10.1302/0301-620X.98B6.35686

[22] Garg et al 2014 [ibid].

[23] Robb 2009 [ibid].