Controlling Femoral Derotation Osteotomy With Electromagnetic Tracking

Controlling Femoral Derotation Osteotomy With Electromagnetic Tracking - an in Vivo Study

The study is designed to evaluate the use of electromagnetic tracking in femoral derotation osteotomies. The goal is to raise the precision of the surgical procedure in order to improve the outcome in short- and long term. The electromagnetic tracking system is evaluated against a base line CT scan serving as reference standard.

Study Overview

• Status: Unknown
• Conditions: Cerebral Palsy; Interna Rotation Gait; Malrotation; Bone; In-toing
• Intervention / Treatment: Other: Electromagnetic tracking unit in femoral derotation surgery

Detailed Description

Internal rotation gait is a common deformity in children, especially in those with spastic diplegia. The treatment includes soft tissue and bony correction. Especially the bony procedures e.g. femoral derotation osteotomies have proven to be effective both in short term and long term evaluation. Nonetheless there is still a relevant number of patients that suffer from over- or under-correction and recurrence over time. The reasons are diverse and include false measurement of the derotation in OR.

The study now evaluates electromagnetic tracking for femoral derotation to improve these results.

The patients are recruited from the outpatients department and included if they meet the criteria.

A baseline rotational CT scan and a 3-D-gait analysis are performed and the derotation measured with the EMT system in OR. The results of the measurement is invisible and unknown to the surgeon as the system unit is controlled by a technician.

The surgical procedure follows standard rules and does not need alterations because of the study.

After the operation a second rotational CT scan is performed and the derotation precisely evaluated by two raters and later compared to the results of the electromagnetic tracking system.

• Study Type: Interventional
• Enrollment (Anticipated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Heidelberg, Germany, 69118
    • Recruiting
    • Orthopaedic Department, University of Heidelberg
    • Contact: Thomas Dreher, Dr.; Email: thomas.dreher@med.uni-heidelberg.de
    • Contact: Andreas Geisbüsch, Dr.; Email: andreas.geisbuesch@med.uni-heidelberg.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• functionally impairing internal rotation gait and indication for supracondylar derotation osteotomy (Evidence of falling because of internal rotation gait, abnormally increased femoral anteversion, confirmation of internal rotation gait in gait kinematics of hip rotation and foot progression angle and a mid point shift in the clinical examination).

Exclusion Criteria:

• severe mental retardation and inability to undertake the CT scan

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: EMT Arm; The study is performed with a single arm, as the system is an additional tool for derotation measurement and the surgical procedure itself and its technique is not changed.

Other: Electromagnetic tracking unit in femoral derotation surgery; Use of the electromagnetic tracking system during the surgical procedure in addition to the normal measurement with goniometer, the different devices listed are combined to form the EMT system unit; Other Names: A self developed software interface; EMT pointer device (FlexPointer E01 2002, fiagon GmbH, Berlin, Germany) for surface sampling; EMT sensors embedded in a clamp shell (PointerShell E01 2902, fiagon GmbH, Berlin, Germany); A field generator (AURORA v.2, Northern Digital, Waterloo, Canada)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference between CT reference measurement and EMT measurement of femoral derotation osteotomies in degrees	The study evaluates the result of the derotation measurement by the EMT system against the derotation in degrees that is measured with the difference between the pre- and the post-operative CT scan (meaning: EMT measurement intra-operative versus difference in femoral rotation in the CT scan between pre- and post-operative CT). The outcome is given in degrees.	After the postoperative CT Scan (maximum of three month after surgery)

Collaborators and Investigators

• Sponsor: Heidelberg University
• Investigators: Principal Investigator: Thomas Dreher, Dr., MD

Publications and helpful links

General Publications

• Geisbusch A, Auer C, Dickhaus H, Niklasch M, Dreher T. Electromagnetic bone segment tracking to control femoral derotation osteotomy-A saw bone study. J Orthop Res. 2017 May;35(5):1106-1112. doi: 10.1002/jor.23348. Epub 2016 Jul 4.

Study record dates

Study Major Dates

• Study Start: July 1, 2013
• Primary Completion (Anticipated): July 1, 2017
• Study Completion (Anticipated): October 1, 2017

Study Registration Dates

• First Submitted: November 15, 2016
• First Submitted That Met QC Criteria: November 28, 2016
• First Posted (Estimate): November 29, 2016

Study Record Updates

• Last Update Posted (Estimate): November 29, 2016
• Last Update Submitted That Met QC Criteria: November 28, 2016
• Last Verified: November 1, 2016

More Information

Terms related to this study

• Keywords: Electromagnetic tracking; Internal rotation gait; Femoral derotation osteotomy
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Brain Damage, Chronic; Cerebral Palsy
• Other Study ID Numbers: NavDo2014

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO