What is a sequestrectomy?

What is Sequestrectomy?

Sequestrectomy is a surgical procedure involving the removal of a sequestrum—a piece of dead, necrotic bone that has separated from surrounding viable bone—typically performed to reduce soft tissue irritation, control infection, and promote healing in conditions like osteomyelitis, medication-related osteonecrosis of the jaw (MRONJ), and osteoradionecrosis (ORN). 1

Definition and Pathophysiology

A sequestrum is devitalized bone that has become separated from surrounding healthy bone during the process of necrosis. 2 This occurs when bone loses its blood supply due to:

• Infection (osteomyelitis) causing thrombosis of blood vessels 3
• Radiation damage to bone vascularity (osteoradionecrosis) 1, 4
• Medication effects from bisphosphonates or other bone-modifying agents (MRONJ) 1
• Trauma leading to vascular compromise 5

The dead bone fragment becomes radiographically visible as a dense, calcified piece within a lucent (dark) area on imaging, completely separated from surrounding bone. 2

Clinical Indications for Sequestrectomy

In Medication-Related Osteonecrosis of the Jaw (MRONJ)

Sequestrectomy is recommended for all stages of MRONJ when superficial necrotic bone causes ongoing soft tissue irritation or when loose bony sequestra are present. 1

The ASCO/MASCC/ISOO guidelines specify:

• Stage 1 MRONJ: Minor surgical procedures to remove dead bone sequestration are recommended to reduce soft tissue trauma 1
• Stage 2 MRONJ: Conservative yet definitive removal of bone fragments that irritate soft tissue should be performed 1
• Stage 3 MRONJ: A superficial, well-defined sequestrum should be removed if atraumatic to surrounding tissue 1

The key principle is that areas of superficial necrotic bone causing soft tissue irritation and loose bony sequestra should be removed or recontoured to optimize soft tissue healing, regardless of MRONJ stage. 1

In Osteoradionecrosis (ORN)

For partial thickness ORN where bone maintains structural integrity:

• Small defects <2.5 cm may heal spontaneously with local measures including sequestrectomy 1
• Removal of superficial bony sequestra should be performed if viewed as low risk to reduce disease burden and biofilm environment 1

In Osteomyelitis

Sequestrectomy plays a role in chronic osteomyelitis management:

• Surgical intervention is indicated when substantial bone necrosis is present 6
• Residual necrotic or infected bone should be resected if treatment fails 6
• The procedure allows for revascularization through periosteal formation of involucrum (new bone) and creeping substitution 3, 7

Surgical Technique Considerations

Conservative vs. Aggressive Approach

A conservative surgical approach is preferred over aggressive resection in most cases. 1

The evidence shows:

• Two prospective studies found no significant difference in healing rates between surgical and nonsurgical treatments 1
• Two additional prospective studies reported that less aggressive surgical therapy may produce better outcomes than more aggressive approaches 1
• With the exception of advanced stage 3 disease or well-defined sequestra, operative therapies should be considered only when nonoperative strategies have failed 1

Specific Technical Points

• The procedure should be atraumatic to contiguous tissue 1
• Removal should focus on loose fragments and bone causing soft tissue irritation 1
• Recontouring of sharp bony edges optimizes soft tissue healing 1
• Primary wound closure can be attempted with good success 5

Novel Approaches

CO2 laser sequestrectomy has shown promising results as an office-based technique for ORN, with complete resolution of pain and mucosal coverage in small case series. 4 This represents an emerging alternative to traditional mechanical bone removal.

Timing and Clinical Context

When to Perform Sequestrectomy

Early sequestrectomy is beneficial when:

• A well-defined sequestrum has formed 1
• Soft tissue irritation is present 1
• The fragment is loose or mobile 1
• Conservative management has failed 1

Sequestrectomy should be avoided when:

• Bone is not clearly demarcated from viable tissue 1
• Extensive resection would be required 1
• The patient is medically unfit for surgery 1

Adjunctive Measures

Sequestrectomy should be combined with:

• Antimicrobial mouth rinses 1, 8
• Systemic antibiotic therapy when clinically indicated 1, 8
• Meticulous oral hygiene 1
• Pain control with analgesics 1

Expected Outcomes

Long-term prognosis after sequestrectomy is favorable when performed appropriately. 5

• Sequestration typically develops within 8-15 months in MRONJ cases treated with antibiotics 1
• Normal limb function can be restored in long bone cases, though cosmetically the affected area may remain enlarged unless exuberant new bone is removed 5
• Complete mucosal coverage and pain resolution occur in ORN cases with appropriate technique 4
• The periosteum can completely repair large structural defects following sequestrectomy through involucrum formation 7

Common Pitfalls to Avoid

• Performing elective dentoalveolar surgery in areas of established MRONJ, which may create additional necrotic bone 1
• Attempting aggressive resection when conservative removal would suffice, as less aggressive approaches may yield better outcomes 1
• Inadequate debridement, which increases infection risk 8
• Delayed surgical intervention when clearly indicated, leading to progressive bone destruction 6
• Removing sequestra too early before adequate demarcation, which may damage viable bone 1