What is the treatment for a suspected chance fracture?

Treatment of Suspected Chance Fracture

For suspected Chance fractures, obtain standard radiographs immediately as first-line imaging, followed by CT without contrast for definitive diagnosis and fracture characterization, then treat surgically with posterior instrumented fusion for unstable patterns (types B, C, D) or conservatively with orthosis for stable bony fractures without neurologic deficits. 1, 2, 3

Initial Diagnostic Approach

Imaging Algorithm

• Standard radiographs are mandatory as the first imaging study for any suspected spinal fracture, including Chance fractures 1
• CT without contrast is the gold standard for thoracolumbar spine fractures, with 94-100% sensitivity and superior ability to characterize fracture morphology 1
• MRI without contrast should be obtained when ligamentous injury is suspected or when neurologic deficits are present, as it provides superior soft-tissue evaluation 1
• The entire spine should be imaged because multilevel fractures occur commonly in spinal trauma 4

Classification and Stability Assessment

• Chance fractures are classified into four varieties based on stability, with surgical stabilization reserved for unstable patterns (types B, C, D) 3
• Unstable fractures demonstrate greater kyphotic deformity (typically >20 degrees) and require surgical intervention 5
• Bony Chance fractures without posterior ligamentous disruption may be more amenable to conservative treatment than ligamentous variants 6, 7

Treatment Decision Algorithm

Surgical Indications (Preferred for Most Cases)

Surgical treatment with posterior instrumented fusion provides superior outcomes compared to conservative management, particularly for:

• Any unstable fracture pattern (types B, C, D) 3
• Kyphotic deformity >15-20 degrees at presentation 5
• Presence of neurologic deficits 5
• Associated posterior ligamentous injury 7
• Inability to maintain alignment with orthosis 5

Surgical Technique

• Percutaneous cannulated pedicle screw fixation allows stable fixation with minimal blood loss and early mobilization 7, 8
• Instrumentation typically spans one level above and below the fracture 7, 8
• CT-guided wire placement improves accuracy, especially in pediatric cases or complex anatomy 8
• Implant removal can be performed at 9 months post-injury once solid fusion is achieved 7

Conservative Treatment (Highly Selective Cases Only)

Conservative management may be considered only for:

• Stable bony Chance fractures without neurologic deficits 6
• Patients with prohibitive surgical risk or who decline surgery 6
• Tolerable mechanical pain without progressive deformity 6

Conservative Protocol

• Rigid orthosis (TLSO or similar) for 3-6 months with serial imaging to monitor alignment 6, 5
• Teriparatide 20 mcg daily for up to 24 months can promote solid union in elderly patients with ankylosed spines when surgery is contraindicated 2, 6
• Adequate calcium (1000-1200 mg/day) and vitamin D (800 IU/day) supplementation is essential, particularly in elderly patients 2
• Serial radiographs every 2-4 weeks initially to detect progression of kyphosis 5

Critical Management Considerations

Neurologic Assessment

• 43% of pediatric Chance fractures present with neurologic deficits, with only partial recovery in many cases 5
• Unrestrained patients have 42% incidence of permanent neurologic deficit versus 10% in restrained patients 5
• Any neurologic deficit mandates urgent MRI and strong consideration for surgical decompression and stabilization 5

Associated Injuries

• Abdominal injuries occur frequently with Chance fractures due to the flexion-distraction mechanism, particularly with lap-belt injuries 5, 8
• Thorough evaluation for intra-abdominal injuries is mandatory before definitive spinal treatment 8
• Multiple spinal fractures may coexist and require comprehensive spine imaging 4

Special Population: Ankylosed Spine

• Fractures in ankylosed spines (ankylosing spondylitis, DISH) are highly unstable due to long lever arms and should generally be treated surgically 6
• When surgery is contraindicated, teriparatide combined with rigid orthosis can achieve solid union even in unstable patterns 6
• These patients require prolonged immobilization (up to 12 months) and close radiographic monitoring 6

Outcomes and Complications

Surgical Outcomes

• 84% good clinical outcome (no chronic pain or neurologic deficit) with surgical treatment versus 45% with conservative treatment 5
• Surgical complications include hardware discomfort (most common), infection, and implant failure 5
• Early mobilization is possible with stable fixation, reducing complications of prolonged bed rest 7

Conservative Treatment Complications

• Progression of kyphotic deformity is the most common complication of nonoperative management 5
• Nonoperative treatment had 26% overall complication rate, primarily related to loss of alignment 5
• Chronic pain and residual deformity are more common with conservative management 5

Common Pitfalls to Avoid

• Do not rely on radiographs alone for diagnosis, as Chance fractures are frequently missed or diagnosis is delayed 3
• Do not assume neurologic recovery will be complete—only 53% of patients with initial deficits fully recover 5
• Do not undertreate pain, as inadequate analgesia can lead to agitation, delirium, and increased stress response 9
• Do not miss associated injuries, particularly intra-abdominal trauma in flexion-distraction mechanisms 5, 8
• Do not use conservative treatment for unstable patterns or significant kyphotic deformity, as progression is highly likely 5