The oscillating micro-saw: a safe and pliable instrument for transverse osteotomy in rhinoplasty

Overview

To narrow a wide bony nose, the side walls are freed by a lateral cut and a transverse cut near the root. The transverse cut is usually made blind with a chisel, and bone near the root varies in brittleness, so it can fracture unpredictably. The author describes making a partial-thickness transverse cut with an oscillating micro-saw through the nostril while watching with an endoscope.

Sections of note

• Review of 1,550 consecutive rhinoplasty and septorhinoplasty operations, April 2005 to October 2010.
• Bilateral transverse osteotomy in 1,374 cases, done with a powered micro-saw from an endonasal approach under video endoscopic control.
• CT-based 3D models from 16 patients with different functional indications measured the bone along the transverse osteotomy line.
• Mean bone thickness at the thickest point near the radix: 2.5 mm (SD 0.66).
• Thickness decreased toward the medial canthus in all 16; mean 1.2 mm (SD 0.21) there.
• The abstract reports no complication or outcome rates from the 1,374 cases.

What it means for a patient

• Powered saws with a camera let the surgeon see the bone cut instead of feeling for it, which is intended to avoid uncontrolled fractures near the eyes.
• The measurements explain why the cut is partial thickness: the bone is only 1 to 3 mm thick.
• Despite the large series, the abstract gives no figures on fractures, bruising or results, so the safety claim is not quantified.

Why this paper matters

This is an early large-series report of powered, endoscopically guided osteotomy, a precursor of the piezoelectric and ultrasonic techniques adopted later. Head-to-head data against manual chisels are not provided.

Terms

• Transverse osteotomy: the horizontal bone cut across the top of the nasal bone near the root that lets the side wall move.
• Lateral osteotomy: the bone cut along the side of the nose at its junction with the cheek.
• Radix: the root of the nose, between the eyes.
• Medial canthus: the inner corner of the eye.
• Endoscopic control: watching the surgical site through a small camera.
• Split-thickness cut: a cut that goes part way through the bone rather than all the way.