Is the 22853 - INSJ (Intervertebral Body Fusion Device) biomechanical device medically necessary for a patient with cervical spine condition and symptoms of neck pain, radiculopathy, and spinal stenosis?

Medical Necessity of Intervertebral Body Fusion Device (22853) for C5-C7 ACDF

The requested intervertebral body fusion device (CPT 22853 x2) is NOT medically necessary for this patient's C5-C7 ACDF based on the coverage policy criteria, as none of the specific indications for synthetic cervical cage/spacer use are met.

Coverage Policy Analysis

The clinical benefit policy explicitly requires one of the following specific indications for synthetic cervical cage/spacer use in cervical fusion 1:

Required Criteria (None Met in This Case)

• Cervical corpectomy (removal of ≥50% of vertebral body) for:
  • Tumors involving vertebrae

  • 50% compression fracture

  • Retropulsed bone fragments
  • Symptomatic central canal stenosis from vertebral body pathology
• Pseudarthrosis with prior fusion
• Adjacent level disease with prior cervical fusion involving a plate (to avoid plate removal dissection when using stand-alone cage)

This Patient's Situation

The patient is undergoing C5-C7 anterior cervical discectomy and fusion (ACDF) for 1:

• Disc degeneration at C5-6 and C6-7
• Posterior spondylotic disc displacements
• Mild cord compression
• Right posterior-foraminal disc-spur complex
• Severe right C7 foraminal stenosis

This is a standard two-level ACDF for degenerative disc disease with radiculopathy and stenosis—NOT a corpectomy procedure. The surgical codes requested (22551,22552) confirm anterior cervical discectomy and fusion, not corpectomy 1.

Biomechanical Considerations

While intervertebral body fusion devices can provide structural support, the evidence does not support their necessity for standard ACDF procedures 2, 3:

• Standard ACDF technique (Smith-Robinson) with structural bone graft provides adequate stability for one or two-level anterior cervical fusions 3
• Biomechanical studies show both ACDF with bone graft and cage-based constructs provide satisfactory spinal stability 2
• The patient meets criteria for the fusion procedure itself (22551,22552) and fixation hardware (22845), which provide adequate stabilization 1

Alternative Approach

The appropriate construct for this patient includes 1, 3:

• Anterior cervical discectomy and fusion (22551,22552) - CERTIFIED
• Anterior cervical plate fixation (22845) - CERTIFIED
• Structural bone allograft (20930) - CERTIFIED

This combination provides adequate biomechanical stability for two-level ACDF without requiring interbody cages 3. The structural allograft (20930) serves as the interbody spacer and fusion substrate, which is the traditional and evidence-supported approach for standard ACDF 3.

Critical Distinction

The coverage policy distinguishes between 1:

• Routine ACDF for disc herniation/spondylosis (this patient) - cages not required
• Corpectomy procedures requiring vertebral body replacement - cages medically necessary

This patient requires discectomy (removal of disc material and osteophytes), not corpectomy (removal of vertebral body). The MRI findings of "posterior spondylotic disc displacements" and "disc-spur complex" indicate disc-level pathology, not vertebral body pathology requiring corpectomy 1.

Common Pitfall to Avoid

Do not conflate the presence of cord compression or severe stenosis with the need for corpectomy or interbody cages 1. Cord compression from posterior disc-osteophyte complexes is appropriately treated with standard ACDF and anterior decompression, which can be achieved through discectomy without requiring synthetic cages 3, 4.