How Much Surface Registration Accuracy is Required Using Ct-based Navigation System in Adolescent Idiopathic Scoliosis Surgery?

Abstract

STUDY DESIGN:

Retrospective, single-center, single-surgeon study.

OBJECTIVE:

This study investigated screw perforation rate according to surface registration accuracy in pedicle screw fixation using a CT-based navigation system for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA:

Posterior spinal fusion for scoliosis correction using pedicle screws is widely adopted but carries a risk of serious neurovascular or visceral structure events. To attempt to avoid these complications, we have been using a computed tomography (CT)-based navigation system during screw insertion, although insufficient surface registration accuracy may be a reason for some screw perforations.

METHODS:

We evaluated 116 AIS patients (9 male and 107 females; mean±standard deviation age: 15.2±2.3 y) who had received pedicle screw fixation guided by a CT-based navigation system between August 2007 and December 2017. Screw perforation rate was evaluated in relation to surface registration accuracy and cut-off values were determined by receiver operating characteristic (ROC) curves.

RESULTS:

A total of 1553 pedicle screws were inserted into T2-L4 vertebrae using CT-based navigation system. The respective overall perforation rates for grade 2 or 3 and grade 3 perforations by surface registration accuracy were 0.2 mm: 0% and 0%; 0.3 mm: 3.5% and 0%; 0.4 mm: 3.5% and 0.8%; 0.5 mm: 8.0% and 3.5%; 0.6 mm: 6.7% and 2.7%; 0.7 mm: 8.9% and 3.8%; 0.8 mm: 9.3% and 6.7%; and 0.9 mm: 9.3% and 4.7%. ROC curve analysis revealed a cut-off surface registration accuracy of 0.5 mm. The major screw perforation rate for a surface registration accuracy of ≥0.5 mm was significantly higher than that for <0.5 mm (P<0.01).

CONCLUSIONS:

Analysis of screw perforation rate according to surface registration accuracy demonstrated a clinical cut-off of 0.5 mm. Thus, surface registration accuracy should optimally be <0.5 mm for scoliosis surgery with CT-based navigation system.

• Authors: Masashi Uehara, Jun Takahashi, Shota Ikegami, Shugo Kuraishi, Toshimasa Futatsugi, Hiroki Oba, Takashi Takizawa, Ryo Munakata, Michihiko Koseki, Hiroyuki Kato
• Journal: Clinical spine surgery (Clin Spine Surg) Vol. 32 Issue 3 Pg. E166-E170 (04 2019) ISSN: 2380-0194 [Electronic] United States
• PMID: 30507639 (Publication Type: Evaluation Study, Journal Article)

Topics

• Adolescent
• Female
• Humans
• Lumbar Vertebrae
• Male
• Pedicle Screws
• Retrospective Studies
• Scoliosis (diagnostic imaging, surgery)
• Spinal Fusion
• Surgery, Computer-Assisted
• Thoracic Vertebrae
• Tomography, X-Ray Computed
• Treatment Outcome