A Research Study to Understand and Predict the Failure of Shoulder Fracture Fixations Using Computer Simulations

NCT04056351 | Completed

• 1 other identifier: AR2018_01
• Study Type: interventional
• Target: 29
• Locations: 2 countries
• Sites: 2

Brief Summary

Fractures of the shoulder, the so-called proximal humeral fractures, can be treated with locking plates that have shown good results in clinical practice, but complications can occur. In order to further improve the treatment of proximal humerus fractures and decrease the rate of fixation failures, further research is necessary. As a first step, the reasons for potential implant failures need to be understood. This study has been initiated by scientists at the AO Research Institute Davos (ARI), Switzerland, which is the research center of the AO Foundation (www.aofoundation.org), an international non-profit organization led by surgeons specialized in fractures such as these. Researchers at the ARI have been developing a computational simulation tool to predict fixation failure and demonstrated its efficiency in laboratory conditions. This clinical study has been organised to validate this tool using patient data, by comparing the risk of mechanical failure predicted by the computer simulated model with the clinically observed fixation failure. In future, this computer simulation tool is expected to help surgeons to select the best fixation for a given patient and to develop improved implants.

Conditions

Proximal Humeral Fracture

Keywords

humerus; fracture; locking plate; PHILOS; fixation failure risk; computer simulation; patient activity tracking

Outcome Measures

Primary Outcomes (2)

• Fixation failure risk estimated from the structural capacity (strength) of the fixation

  Fixation failure risk estimated from the structural capacity (strength) of the fixation will be predicted by the patient-specific computer simulation based on the collected: * pre-OP CT images * post-OP CT images * surgical details.

  6 months post-op

• Clinical occurrence of radiographically confirmed mechanical fixation failure

  Clinical occurrence of radiographically confirmed mechanical fixation failure within 6 months after PHILOS plate treatment (failure / no failure status). Mechanical failures are defined as: * loss of reduction (≥ 15° increase of varus malposition between the immediate post-OP position and FU radiograph, and/or relative change (5 mm) of greater or lesser tuberosity compared to the immediate post-OP position) * cut-out failure (≥ 5 mm distal displacement of the humeral head fragment between immediate post-OP and FU) * head impaction (≥ 5 mm difference in outer plate edge and tangent of humeral head between immediate post-OP and FU), and/or * secondary screw perforation (Perforation of one or more screws through the humeral head on the FU radiograph (and lack of screw perforation on the intra- or post-OP radiograph based on a direct post-OP AP and axial radiographs))

  6 months post-op

Secondary Outcomes (2)

• Fixation failure risk predicted by the simulation when activity information is included in the model

  4 days post-op

• Fixation failure risk predicted by the simulation when actual post-OP shoulder activity information is included in the model

  6 weeks post-op

Study Arms (1)

Cohort of 50 enrolled patients

OTHER

The following visits will be performed: direct post-OP, 3 weeks, 6 weeks, 3 months and 6 months after surgery. Surgical details will be assessed from the surgical notes. Medical images will be collected according to the standard of care. A post-OP CT scan will also be acquired when the treating surgeon requests it as per standard of care, or additionally, as a study specific imaging procedure for the rest of the participants. Patient activity will be estimated based on various factors, including questionnaires on demographics, activity level, comorbidity score and contralateral grip strength. The actual post-OP shoulder activity will be measured by motion tracking by means of sensors attached to upper arm of the treated side and on the chest for 6 weeks and by grip strength assessed at the treated arm at week 6. Fixation failure status will be determined 6 months post-OP. Imaging and details regarding the fixation failure event will be sent to ARI.

Diagnostic Test: Post-Operative (OP) Computer Tomography (CT); Other: Questionnaires on patient activity and comorbidities; Other: Grip strength measurement; Other: Non-invasive shoulder activity tracking usinig wearable sensors

Interventions

Post-Operative (OP) Computer Tomography (CT) DIAGNOSTIC_TEST

Post-OP CT of the treated shoulder

Cohort of 50 enrolled patients

Questionnaires on patient activity and comorbidities OTHER

* Shoulder activity scale (Marx) * Parker Mobility Scale * Barthel index * Charlson Comorbidity Score

Cohort of 50 enrolled patients

Grip strength measurement OTHER

Grip strength will be measured using a CE marked hydraulic hand dynamometer device.

Cohort of 50 enrolled patients

Non-invasive shoulder activity tracking usinig wearable sensors OTHER

Post-OP activity will be assessed via wearable CE-marked accelerometer sensors.

Cohort of 50 enrolled patients

Eligibility Criteria

• Age: 50 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age≥ 50 years
• Radiologically confirmed closed fracture of the proximal humerus and treatment within 10 days after injury
• Any displaced or unstable 3- or 4-part fracture of the proximal humerus except isolated displaced fractures of the greater or lesser tuberosity
• Completed primary fracture treatment with a PHILOS plate with or without cement augmentation of the screws
• Ability to understand the content of the patient information / informed consent form
• Willingness and ability to participate in the clinical investigation including imaging, activity tracking and other FU procedures
• Signed informed consent

You may not qualify if:

• Previous proximal humerus fracture on the ipsilateral side
• Splitting fracture of the humeral head or humeral head impression fracture
• Fibula grafting, bone block or any other non-cement augmentation of the PHILOS plate fixation
• Any serious fracture fixation issue (serious malreduction, too long screw or screw perforating through the humeral head, broken screw or implant) that are recognized on the immediate post-OP x-rays, independently of being re-operated or not
• Associated nerve or vessel injury
• Any severe systemic disease: class 4 - 5 of the American Society of Anesthesiologists (ASA) physical status classification
• Recent history of substance abuse (i.e., recreational drugs, alcohol) that would preclude reliable assessment
• Prisoner
• Participation in any other medical device or medicinal product study within the previous month that could influence the results of the present study
• Pregnancy
• Pacemaker

Sponsors & Collaborators

• AO Research Institute Davos: lead

Study Sites (2)

Medical University of Innsbruck

Innsbruck, Austria

Location

UZ Leuven

Leuven, Belgium

Location

Related Publications (2)

• Varga P, Inzana JA, Gueorguiev B, Sudkamp NP, Windolf M. Validated computational framework for efficient systematic evaluation of osteoporotic fracture fixation in the proximal humerus. Med Eng Phys. 2018 Jul;57:29-39. doi: 10.1016/j.medengphy.2018.04.011. Epub 2018 May 1.

  PMID: 29728330 BACKGROUND

• Varga P, Grunwald L, Inzana JA, Windolf M. Fatigue failure of plated osteoporotic proximal humerus fractures is predicted by the strain around the proximal screws. J Mech Behav Biomed Mater. 2017 Nov;75:68-74. doi: 10.1016/j.jmbbm.2017.07.004. Epub 2017 Jul 4.

  PMID: 28697401 BACKGROUND

MeSH Terms

Conditions

Shoulder Fractures; Fractures, Bone

Interventions

Comorbidity

Condition Hierarchy (Ancestors)

Wounds and Injuries; Shoulder Injuries

Intervention Hierarchy (Ancestors)

Epidemiologic Factors; Quality of Health Care; Health Care Quality, Access, and Evaluation; Public Health; Environment and Public Health

Study Officials

• Peter Varga, PhD

  AO Research Institute Davos

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: SCREENING
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 12, 2019
• First Posted: August 14, 2019
• Study Start: August 2, 2019
• Primary Completion: December 31, 2022
• Study Completion: December 31, 2022
• Last Updated: February 1, 2023

Record last verified: 2023-01

Data Sharing

• IPD Sharing: Will not share

Locations

BE (1); AU (1)