Anterior Column Realignment (ACR) in Adult Sagittal Deformity Correction: Technique and Review of the Literature

Spine (Phila Pa 1976). 2016 Apr:41 Suppl 8:S66-73. doi: 10.1097/BRS.0000000000001483.

Abstract

Study design: The anterior column realignment (ACR) procedure was retrospectively reviewed.

Objective: To review surgical technique, complication avoidance, case examples, and published results on ACR.

Summary of background data: For surgical correction of sagittal imbalance, three column osteotomies (3CO) have traditionally been employed for large degrees of correction at a single segment. However, 3CO procedures are technically challenging and carry high morbidity rates. ACR was developed as a less invasive procedure for restoring segmental lordosis.

Methods: The ACR surgical technique is reviewed. ACR involves either a lateral, trans-psoas or anterior retroperitoneal approach to sectioning the anterior longitudinal ligament/annulus and placing a hyperlordotic cage. ACR usually also involves a second stage posterior column osteotomy. Three case examples are presented. A review of literature on ACR papers was completed.

Results: Twelve papers met inclusion criteria. Ten to 27° of segmental lordosis were reported with use of hyperlordotic cages. 19° increase in mean intradiscal angle was reported when ACR was combined with posterior column osteotomy, 13° more than lateral lumbar interbody fusion alone without a hyperlordotic implant. Reported complication rates ranged from 18 to 47%. The most common minor complications were transient hip flexion weakness (9.3%) and transient paresthesia or dysesthesia (12%). There were few reports of major complications, such as bowel perforation (n = 1) or vascular injury (n = 1). Motor deficit was reported in 11 of 75 cases, lower than reported rates for 3CO.

Conclusion: ACR is an emerging, less invasive technique for correction of sagittal deformity ACR has similar restorative capacity as other techniques with same or lower complication rates.

Level of evidence: 4.

Publication types

  • Review

MeSH terms

  • Aged
  • Female
  • Humans
  • Male
  • Middle Aged
  • Minimally Invasive Surgical Procedures* / adverse effects
  • Minimally Invasive Surgical Procedures* / methods
  • Minimally Invasive Surgical Procedures* / statistics & numerical data
  • Orthopedic Procedures* / adverse effects
  • Orthopedic Procedures* / methods
  • Orthopedic Procedures* / statistics & numerical data
  • Postoperative Complications
  • Retrospective Studies
  • Spinal Curvatures / diagnostic imaging
  • Spinal Curvatures / pathology
  • Spinal Curvatures / surgery*
  • Spine / diagnostic imaging
  • Spine / pathology
  • Spine / surgery