Condition category
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Background and study aims
Decompressive hemicraniectomy is a routine life-saving brain surgery. It involves cutting out a section of bone from the skull to release pressure caused by the brain swelling and pressing against the skull. Swelling can occur for a variety of reasons, including traumatic brain injury and stroke. Decompressive hemicraniectomy is used when other ways of reducing pressure inside the skull have failed or cannot be used. After the brain swelling has reduced, the bone flap (which has been stored frozen) should be reattached into the skull to restore normal appearance and brain protection. This procedure is called an autologous cranioplasty. Although this is a straightforward surgical procedure, there is a fairly high rate of infection or other problems, such as the bone flap breaking down or dying. If the bone flap does not heal back into the skull, it must be removed and a custom-made artificial implant is used to fill the hole. The aim of this study is to analyse medical records of people who have had this procedure as part of their normal treatment to identify if there are factors that contribute to cranioplasty failure, so that these can be adjusted in the future to reduce the complication rate.

Who can participate?
The records of all patients aged 16-90 years who had decompressive hemicraniectomy at Aachen University Hospital were examined and only those who also had autologous cranioplasty in 2010-2018 and had been followed up for at least 1 year were included. Children whose skulls were still growing were excluded.

What does the study involve?
The analysis was conducted on medical records of patients who had these procedures as part of normal treatment.

What are the possible benefits and risks of participating?
There are no benefits or risks of participating in the study because all patients received treatment as usual before the study was initiated.

Where is the study run from?
Aachen University Hospital (Germany)

When is the study starting and how long is it expected to run for?
October 2016 to December 2018

Who is funding the study?
Aachen University Hospital (Germany)

Who is the main contact?
Dr Michael Veldeman,

Trial website

Contact information



Primary contact

Dr Michael Veldeman


Contact details

Pauwelstrasse 30

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number


Study information

Scientific title

Identifying adjustable risk factors for surgical site infection and aseptic bone resorption after autologous cranioplasty after decompressive hemicraniectomy



Study hypothesis

We hope to identify surgery-specific risk factors and predictors of surgical site infection in patients after decompressive hemicraniectomy, for example operative time, timing of surgery (time between decompressive hemicraniectomy and cranioplasty), pre-cranioplasty laboratory results such as white blood cell count, and C-reactive protein (indicative for an ongoing infection) or incision type.

Ethics approval

Approved 17/04/2014, Ethics Committee of the Medical Faculty of Rheinisch-Westfälischen Technischen Hochschule Aachen [RWTH Aachen University] (Pauwelstrasse 30, 52074 Aachen, Germany; +49 241 80-89963;, ref: EK 062/14

Study design

Retrospective cohort analysis

Primary study design


Secondary study design

Cohort study

Trial setting


Trial type


Patient information sheet

No participant information sheet available.


Decompressive hemicraniectomy for the following diagnoses: malignant middle cerebral artery infarction, severe traumatic brain injury, subarachnoid hemorrhage or intracerebral hemorrhage.


The intervention has been performed as a clinical decision independent of this observational retrospective analysis. Patients do not need additional examinations or interventions as part of this trial.
All patient underwent the implantation of their own cranial bone flap as part of routine medical practice in decompressive hemicraniectomy. All patients were routinely followed up as part of normal care. The post-surgical period of follow-up was at least 12 months. Patients who were lost to follow-up before the 12 months had passed were excluded.

Intervention type



Drug names

Primary outcome measure

Occurrence of surgical site infection, defined as a visible wound infection with or without dehiscence, or a positive spinal tap indication CSF infection requiring the removal of the implanted autologous bone flap. This was assessed by examining patients' medical records up to 8 years post-surgery. The minimal duration of follow-up for inclusion was 1 year.

Secondary outcome measures

Occurrence of aseptic bone resorption requiring the need for redo surgery and implantation of an allograft bone flap assessed by examining patients' medical records up to 8 years post-surgery. The minimal duration of follow-up for inclusion was 1 year.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Aged 16-90 years at time of surgery
2. Treated using decompressive hemicraniectomy between 2010 and 2018 due to malignant stroke, traumatic brain injury, subarachnoid hemorrhage or intracerebral hemorrhage

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Decompressive hemicraniectomy for other diagnoses i.e. infection, post-tumor surgery etc
2. Children with a growing skull (aged <16 years)
3. Immunosuppressed patients (including iatrogenic)

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

University Hospital Aachen
Pauwelstrasse 30

Sponsor information


University Hospital Aachen [Universitätsklinikum Aachen]

Sponsor details

Pauwelstrasse 30

Sponsor type

Hospital/treatment centre



Funder type


Funder name

Medizinische Fakultät, RWTH Aachen University

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

After data acquisition out of existing patient records, data will be statistically analyzed. The results will be published in a peer-reviewed neurosurgical journal.

IPD sharing statement:
Anonymized data will be shared upon request to qualified researchers either by e-mail or by post.

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

21/11/2019: Internal review. 30/10/2019: Trial's existence confirmed by University Hospital Aachen [Universitätsklinikum Aachen].