DensiProbe Spine: a novel instrument for intraoperative measurement of bone density in transpedicular screw fixation

Deckelmann, S; Schwyn, R; Van der Pol, B; Windolf, M; Heini, PF; Benneker, LM (2010). DensiProbe Spine: a novel instrument for intraoperative measurement of bone density in transpedicular screw fixation. Spine, 35(6), pp. 607-12. Hagerstown, Md.: Lippincott Williams & Wilkins 10.1097/BRS.0b013e3181bc9470

Full text not available from this repository. (Request a copy)

STUDY DESIGN.: Cadaver study. OBJECTIVE.: To determine bone strength in vertebrae by measuring peak breakaway torque or indentation force using custom-made pedicle probes. SUMMARY OF BACKGROUND DATA.: Screw performance in dorsal spinal instrumentation is dependent on bone quality of the vertebral body. To date no intraoperative measuring device to validate bone strength is available. Destructive testing may predict bone strength in transpedicular instrumentations in osteoporotic vertebrae. Insertional torque measurements showed varying results. METHODS.: Ten human cadaveric vertebrae were evaluated for bone mineral density (BMD) measurements by quantitative computed tomography. Peak torque and indentation force of custom-made probes as a measure for mechanical bone strength were assessed via a transpedicular approach. The results were correlated to regional BMD and to biomechanical load testing after pedicle screw implementation. RESULTS.: Both methods generated a positive correlation to failure load of the respective vertebrae. The correlation of peak breakaway torque to failure load was r = 0.959 (P = 0.003), therewith distinctly higher than the correlation of indentation force to failure load, which was r = 0.690 (P = 0.040). In predicting regional BMD, measurement of peak torque also performed better than that of indentation force (r = 0.897 [P = 0.002] vs. r = 0.777 [P = 0.017]). CONCLUSION.: Transpedicular measurement of peak breakaway torque is technically feasible and predicts reliable local bone strength and implant failure for dorsal spinal instrumentations in this experimental setting.

Item Type:

Journal Article (Original Article)


04 Faculty of Medicine > Department of Orthopaedic, Plastic and Hand Surgery (DOPH) > Clinic of Orthopaedic Surgery

UniBE Contributor:

Deckelmann, Stephan; Heini, Paul Ferdinand and Benneker, Lorin Michael




Lippincott Williams & Wilkins




Factscience Import

Date Deposited:

04 Oct 2013 14:08

Last Modified:

04 May 2014 23:04

Publisher DOI:


PubMed ID:


Web of Science ID:


URI: (FactScience: 200663)

Actions (login required)

Edit item Edit item
Provide Feedback