Controlling Femoral Derotation Osteotomy With Electromagnetic Tracking

Heidelberg University

Status: Unknown

Conditions: In-toing; Cerebral Palsy; Malrotation; Bone; Interna Rotation Gait

Treatments: Other: Electromagnetic tracking unit in femoral derotation surgery

Study type: Interventional

Funder types: Other

Identifiers

NCT02976532

NavDo2014

Details and patient eligibility

About

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.

Full 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.

Enrollment: 20 estimated patients

Sex: All

Ages: 18 to 40 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Diagnostic

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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20 participants in 1 patient group

EMT Arm

Other group

Description:

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.

Treatment:

Other: Electromagnetic tracking unit in femoral derotation surgery