Sacroiliac (SI) joint dysfunction contributes to up to 30% of chronic low back pain cases【Forst et al., 2006†source】. When conservative care fails, SI joint fusion can provide lasting relief【Dreyfuss et al., 2004†source】. This article highlights two approaches — a well-established lateral fixation system and a newer percutaneous lateral-oblique technique — and summarizes their key differences.

Established Lateral Fixation Techniques

Systems like iFuse (SI-Bone) use triangular titanium implants inserted across the joint via a lateral approach. This method has been widely studied and shows significant improvements in pain and function. However, it typically requires more soft-tissue exposure and may involve longer recovery times【Cahueque et al., 2023†source】.

Emerging Lateral-Oblique Techniques

The Sacrix™ SI Fusion System introduces a percutaneous, lateral-oblique approach using variable-threaded screws for fixation. This technique preserves the joint capsule, minimizes soft-tissue disruption, and is performed as a same-day outpatient procedure. Multicenter studies show it can be safely and effectively performed by trained interventionalists, supporting quicker recovery and early mobilization【Chin et al., 2025†source】.

Key Distinctions

• Surgical Exposure
  Lateral Fixation (e.g., iFuse): Direct lateral
  Lateral-Oblique (Sacrix): Minimally invasive percutaneous

• Implant Design
  Lateral Fixation (e.g., iFuse): Triangular titanium
  Lateral-Oblique (Sacrix): Variable-threaded screws

• Capsule Preservation
  Lateral Fixation (e.g., iFuse): Not preserved
  Lateral-Oblique (Sacrix): Preserved

• Recovery Profile
  Lateral Fixation (e.g., iFuse): Longer recovery
  Lateral-Oblique (Sacrix): Quicker return to activity

• Training Evidence
  Lateral Fixation (e.g., iFuse): Extensive surgeon-led data
  Lateral-Oblique (Sacrix): Competency shown with interventional pain physicians【Chin et al., 2025†source】

Conclusion

Both approaches have demonstrated clinical benefit in appropriately selected patients. The lateral-oblique percutaneous method represents an evolution in SI joint fusion, aligning with the LESS™ Society’s R.E.P. philosophy — Restore function, Enable early mobility, Preserve anatomy — offering patients less invasive options with promising outcomes.