ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12620000089932

Ethics application status

Approved

Date submitted

11/12/2019

Date registered

3/02/2020

Date last updated

16/01/2024

Date data sharing statement initially provided

3/02/2020

Date results provided

16/01/2024

Type of registration

Prospectively registered

Titles & IDs

Public title

Accuracy of a new navigation system for total hip replacement

Scientific title

Concurrent validity of intraoperative imageless navigation (Naviswiss™) for component positioning accuracy in primary total hip arthroplasty: A prospective observational cohort study in a single-surgeon practice with three-dimensional reconstruction of computed tomography as gold standard

Secondary ID [1]

None

Universal Trial Number (UTN)

U1111-1245-2469

Trial acronym

Linked study record

This study is a sub-study of ACTRN12618000317291, incorporating a subset of the patients eligible for inclusion in the patient registry.

Health condition

Health condition(s) or problem(s) studied:

Hip Osteoarthritis

Hip Rheumatoid Arthritis

Osteonecrosis of the Femoral Head

Condition category

Condition code

Musculoskeletal

Osteoarthritis

Musculoskeletal

Osteoarthritis

Surgery

Surgical techniques

Musculoskeletal

Other muscular and skeletal disorders

Intervention/exposure

Study type

Observational

Patient registry

False

Target follow-up duration

Target follow-up type

Description of intervention(s) / exposure

Total Hip Arthroplasty with a cemented standard stem and cementless acetabular cup, using an anterolateral approach. Guidance for component positioning will be provided intraoperatively using the Naviswiss image-free navigation system, as is standard for this surgeon. The Naviswiss system uses single-use tags which are pinned to relevant anatomical regions, and a handheld camera to collect measurements relevant to positioning of the hip implants both before, during and after component insertion.

As per the surgeon's standard practice, the same patients will undergo a preoperative, and a follow-up CT scan at 6-8 weeks following surgery (therefore the total observation duration will be 6-8 weeks). These scans will be used to provide positioning measurements which will be compared to those obtained in surgery with the navigation device.

Intervention code [1]

Not applicable

Comparator / control treatment

Computed tomography, completed pre and postoperatively, with measurements compared to those obtained with the navigation device from the same patients.

Control group

Active

Outcomes

Primary outcome [1]

Validity of Naviswiss measurements of acetabular cup inclination.
Assessed by comparison between intraoperative Naviswiss and postoperative CT-based measurements (standard error of measurement).

Timepoint [1]

6-12 weeks postoperative

Primary outcome [2]

Validity of Naviswiss measurements of acetabular cup anteversion.
Assessed by comparison between intraoperative Naviswiss and postoperative CT-based measurements (standard error of measurement).

Timepoint [2]

6-12 weeks postoperative

Primary outcome [3]

Validity of Naviswiss measurements of change in femoral offset pre-post implant.
Assessed by comparison between intraoperative Naviswiss measurements, and pre and postoperative CT-based measurements (standard error of measurement).

Timepoint [3]

6-12 weeks postoperative

Secondary outcome [1]

Validity of Naviswiss measurements of change in leg length pre-post implant.
Assessed by comparison between intraoperative Naviswiss measurements, and pre and postoperative CT-based measurements (standard error of measurement).

Timepoint [1]

6-12 weeks postoperative

Secondary outcome [2]

Inter-observer reliability of CT measurements. Two external observers will perform measurements of the listed outcomes using medical image analysis software, on a random selection of ten cases.

Timepoint [2]

6-12 weeks postoperative

Secondary outcome [3]

Intra-observer reliability of CT measurements. One observer will perform measurements of the listed outcomes using medical image analysis software, on a random selection of ten cases twice, with each measurements made at least two weeks apart.

Timepoint [3]

6-12 weeks postoperative

Eligibility

Key inclusion criteria

Patients eligible for primary elective THA using an anterolateral approach in the supine position

Minimum age

18 Years

Maximum age

No limit

Sex

Both males and females

Can healthy volunteers participate?

Key exclusion criteria

Patients who have declined or revoked consent for use of clinical data for research, or unable to provide informed consent.

Patients requiring/electing to have simultaneous bilateral procedures

Patients with severe contralateral hip deformity or dysplasia

Patients eligible for insertion of a short-stem component

Patients with previous ipsilateral hip arthroplasty eligible for revision

Study design

Purpose

Duration

Selection

Timing

Statistical methods / analysis

The sample size was established to provide adequate power to detect a 2.5° absolute mean difference between intraoperative navigation results and postoperative CT measurements for inclination and version using a paired t-test design (each patient acts as their own control), with an assumed between-patient standard deviation of 5°. The standard deviation was estimated from an initial pilot of 15 cases during the learning curve (2.4° for inclination and 2° for version) with an additional margin of error added. Power (beta) was selected at 0.8 and alpha of 0.05 with an estimated sample size of 34 cases required.

The intraoperative data and postoperative CT measurements of the primary outcomes by the primary observer will be compared using mixed effects linear regression. The sample size necessary for the multivariable regression analysis (N = 30) with patient age at surgery, sex and body mass index selected as the model predictors was estimated from a model R-squared of 0.3, three predictors and the same beta and alpha.

The sample size necessary to establish intra and inter-observer reliability of the post-operative CT measurements (N = 10) was estimated from a two-sided test of correlation within and between observers, with an R-squared of 0.5 and a beta/alpha ratio of 1. A sample of 10 cases also provides a 95% confidence interval around the primary and secondary observer average estimates with a 95% confidence interval around a margin of error of 3° (version/inclination) and a standard deviation of 5°.

Recruitment

Recruitment status

Completed

Date of first participant enrolment

Anticipated

5/02/2020

Actual

24/02/2020

Date of last participant enrolment

Anticipated

30/06/2021

Actual

22/08/2021

Date of last data collection

Anticipated

11/07/2021

Actual

4/10/2021

Sample size

Target

Accrual to date

Final

Recruitment in Australia

Recruitment state(s)

NSW

Recruitment hospital [1]

Wollongong Private Hospital - Wollongong

Recruitment hospital [2]

Campbelltown Private Hospital - Campbelltown

Recruitment postcode(s) [1]

2500 - Wollongong

Recruitment postcode(s) [2]

2560 - Campbelltown

Funding & Sponsors

Funding source category [1]

Commercial sector/Industry

Name [1]

Naviswiss AG

Address [1]

Stahlrain 2, 5200 Brugg

Country [1]

Switzerland

Primary sponsor type

Individual

Name

John Ireland

Address

Sydney Bone and Joint Clinic
Building B, Suite 101/4 Hyde Parade,
Campbelltown NSW 2560

Country

Australia

Secondary sponsor category [1]

Commercial sector/Industry

Name [1]

Naviswiss

Address [1]

Stahlrain 2, 5200 Brugg

Country [1]

Switzerland

Secondary sponsor category [2]

Commercial sector/Industry

Name [2]

Active Surgical Pty Ltd

Address [2]

138 Milson Rd,
Cremorne Point NSW 2090

Country [2]

Australia

Other collaborator category [1]

Commercial sector/Industry

Name [1]

EBM Analytics

Address [1]

119 Willoughby Road,
Crows Nest NSW 2065

Country [1]

Australia

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

Bellberry Ltd

Ethics committee address [1]

129 Glen Osmond Road, Eastwood, SA 5063

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

Approval date [1]

03/01/2018

Ethics approval number [1]

HREC2017-07-499

Summary

Brief summary

Optimal outcomes in total hip arthroplasty are dependent on appropriate component placement, with technological advances providing a platform for guiding component placement to reduce the risk of malpositioned components during surgery. This study will validate the accuracy of the data captured using a handheld imageless navigation system (for total hip arthroplasty) against pre/postoperative CT scans. 

Patients are to be recruited and data captured as part of the existing approved protocol for John Ireland's patient registry [ACTRN12618000317291].

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

A/Prof John Ireland

Address

Sydney Bone and Joint Clinic
Building B, Suite 101/4 Hyde Parade,
Campbelltown NSW 2560

Country

Australia

Phone

+61 298212599

Fax

[email protected]

Contact person for public queries

Name

Claire sinclair

Address

Sydney Bone and Joint Clinic
Building B, Suite 101/4 Hyde Parade,
Campbelltown NSW 2560

Country

Australia

Phone

+61 298212599

Fax

[email protected]

Contact person for scientific queries

Name

Corey Scholes

Address

119 Willoughby Road,
Crows Nest NSW 2065

Country

Australia

Phone

+61 299563800

Fax

[email protected]

Data sharing statement

Will individual participant data (IPD) for this trial be available (including data dictionaries)?

No/undecided IPD sharing reason/comment

The data obtained during this study contains both identifiable patient data and commercially sensitive information, and is thus not suitable for sharing.

What supporting documents are/will be available?

Doc. No.	Type	Citation	Link	Email	Other Details	Attachment
6144	Study protocol			[email protected]	The study protocol will be published as a preprint... [More Details]
6145	Ethical approval			[email protected]

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

No additional documents have been identified.

Trial Review

Documents added manually

Documents added automatically