Detection of Bacterial DNA and Collagen Metabolism in Acutely Ruptured Achilles Tendons
Clinicaltrials.gov identifier recruitment status First Posted Last update posted
NCT03931486 Recruiting April 30, 2019 July 14, 2020

study description
Brief Summary

The etiology and pathogenesis of acute Achilles tendon ruptures are complex and not fully understood. It is well known that they are associated with pre-existing pathological alterations, similar to the changes observed in tendinopathy. The present study investigates if bacteria and collagen metabolism play a role in the etiology of acute Achilles tendon rupture. During surgery, 20 patients will have taken two biopsies from the ruptured part of the tendon and two biopsies from the healthy tissue of the same tendon 2-4 cm proximal to the rupture, as a control.

Condition or Disease: Achilles Tendon Rupture
Intervention/treatment:
Phase: N/A
Detailed Description

Objectives

1. To investigate the collagen turnover in Achilles tendons prior to a rupture.

2. To investigate the relative collagen turnover in Achilles tendons the days immediately
after a rupture.

3. To investigate the acute collagen protein synthesis rate in acutely ruptured Achilles
tendons.

4. To investigate if bacterial DNA is present in samples from the degenerative tissue in
acutely ruptured Achilles tendons compared with samples from the healthy tissue of the
ruptured tendon.

Background

Tendon ruptures are severe injuries that potentially lead to reduced function, reduced
activity and sick leave. In younger, sports active individuals with strong tendons, an acute
traumatic event is usually needed to trigger a rupture. With age the tendons are exposed to
degenerative changes and can therefore rupture in everyday activities (spontaneously).

The etiology and pathogenesis of spontaneous tendon ruptures are complex and not fully
understood. It is well known that they are associated with pre-existing pathological
alterations, similar to the changes ob-served in tendinopathy. Recently, Dakin et al. found
that ruptured Achilles tendons show evidence of chronic (non-resolving) inflammation. The
condition might be a result of collagenolytic injury followed by failed tendon healing. Yet,
other theories are still highly debated.

Many predisposing factors have been proposed to contribute to the pathological alterations of
tendons. Studies found that factors such as increasing age, dominant arm, history of trauma
and specific acromial anatomy are associated with rotator cuff tear. It is suggested that
spontaneous tendon ruptures, primary Achilles tendon, are related to systemic and injectable
steroids, fluoroquinolone use and some rheumatic diseases. Furthermore, studies have shown
possible associations between genetic factors and tendon injury. The mentioned factors may
influence the initiation and development of the patho-logical alterations that weaken the
tendons. However, it is certain there are other mechanisms and predis-posing factors that
need to be investigated.

Heinemeier et al. found that the bulk of the collagen matrix of healthy human Achilles tendon
core is an essentially permanent structure that is laid down during height growth and has
limited turnover in adults. The findings were based on the 14C bomb pulse method, and
unpublished data from the same re-search group (using this method) indicates that an
abnormally high rate of collagen turnover precedes symptoms of tendon overuse
(tendinopathy)It is of great interest to investigate if increased collagen turno-ver
predisposes to tendon rupture.

Recently, Rolf et al. demonstrated the presence of bacterial DNA in 25% of samples from
ruptured Achilles tendons. Polymerase chain reaction (PCR) was used to identify the highly
conserved bacterial 16S rDNA gene in the tendons. This finding open the question, if
bacterial depositions play a role in the etiology of spontaneous tendon ruptures In order to
prevent tendon ruptures it is essential to improve our understanding of the etiology. A
better understanding may also lead to development of new therapeutic options.

In this cross-sectional study, we aim to investigate if bacteria potentially are contributing
to the etiology of acute Achilles tendon rupture, Additionally, we also investigate if tendon
ruptures are preceded by an in-creased collagen turnover.

Design of the study

The study is conducted as a cross-sectional study. Patients with acute rupture of the
Achilles tendon are included The study aims to include 20 patients with acute Achilles tendon
rupture.

The procedure for the patient:

1. At the day of inclusion, the patients will have taken a blood sample and ingest 150ml of
deuterium oxide (D2O).

2. At the day of the surgery, the patient will meet 3 hours before the beginning of the
surgery. A bolus of stable isotope (15N marked proline tracer) will be injected and
afterwards continuous infused trough the antecubital vein. Blood samples are taken
before infusion starts, 30min after, 60min af-ter, 120min after and when the biopsies
are taken.

3. During the surgery, the patients will have taken:

1. Two biopsies from the stump end of the ruptured tendon or ligament.

2. Two control biopsies 2-4 cm proximal to the stump end of the ruptured Achilles
tendon.

Procedure for biopsies

All biopsies are taken by trained orthopedic surgeons. Every biopsy is taken during surgery
in an operating theatre. Before the beginning of the surgery a sterile table is prepared
containing three packs of sterile scalpels and forceps, and 8 containers for biopsies with
the patient's social security (CPR), the type of analysis and a continues number individually
describing each biopsy.

The 8 containers will hold:

1. Biopsy from the stump end of the ruptured tendon for 16S rDNA analysis.

2. Biopsy from the stump end of the ruptured tendon for 14C bomb pulse method

3. Biopsy from the stump end of the ruptured tendon for isotope analysis (deuterium oxide
and 15N marked proline).

4. Biopsy from the stump end of the ruptured tendon for mRNA analysis.

5. Biopsy from the ruptured tendon 2-4 cm proximal to the stump end for 16S rDNA analysis.

6. Biopsy from the ruptured tendon 2-4 cm proximal to the stump end for 14C bomb pulse.

7. Biopsy from the ruptured tendon 2-4 cm proximal to the stump end for isotope analysis
(deuterium oxide and 15N marked proline).

8. Biopsy from the ruptured tendon 2-4 cm proximal to the stump end for mRNA analysis

Biopsies from ruptured tendons

Achilles tendon:

The biopsies are taken during open surgery. To prevent contamination of the biopsies the
following proce-dure is followed:

1. Surgical rub and draping according to normal guidelines.

2. Skin incision and dissection according to normal guidelines.

3. As the ruptured tendon is identified, a new pack containing a sterile scalpel and a
forceps is opened. The instruments are only used for taking the biopsy and does not get
in contact with the surrounding tissue.

4. 2 biopsies, 10mm long, 1mm broad and 1mm deep, are taken from the degenerated tendon
tissue at the rupture site.

5. The first biopsy is placed in a container (for bacterial detection). On a sterile board,
the second bi-opsy is divided in three and placed in three different containers (one for
14C bomb pulse, one for isotope analysis (both deuterium oxide and 15N marked proline)
and one for mRNA). These contain-ers are frozen down to -80oC.

6. A second new pack containing a sterile scalpel and a forceps is opened and 2 biopsies 10
mm long, 1mm broad and 1 mm deep are taken 2-4 cm proximal to the rupture site.

7. The first biopsy is placed in a container (for bacterial detection) On a sterile board,
the second biopsy is divided in three and placed in three different containers (one for
14C bomb pulse, one for isotope analysis (both deuterium oxide and 15N marked proline)
and one for mRNA). These contain-ers are frozen down to -80oC.

Contamination tests

PCR and sequencing - Both a negative and a positive control is included in the test. Numbers
of cycles in positive samples will also be included in the interpretation. Exclusively
environmental bacterial species never been related to human disease are likely to be regarded
as contaminants.

Blood culture - During surgery, blood a sample is send for culture to investigate if bacteria
were presented in the blood.

Bacterial cultures - Bacterial culture tests are conducted on all patients. The investigated
samples are taken with swaps from:

- Patients skin area over the surgical site.

- The blade of the used scalpel.

The swaps are collected in separate glass tubes and send to Department of Microbiology,
Hvidovre Hospi-tal. The swaps are tested on multiple culture media for multiple species.

Blinding of the analysis

For each included patient, the 2 containers with biopsies for bacterial detection will get a
randomized continues number. These numbers can, via a key document (paper form), reveal if
the biopsy has been taken from the degenerative tissue or from the healthy tissue. The person
responsible for the analyze of the bacterial DNA has no access to the key document.

Data registration during inclusion

- Patient ID

- Social security number

- Phone number

- Age

- Weight

- Date of examination

- Date and time of insult

- Corticosteroid injection (number and time)

- History of infection


study design
Study Type: Observational
Estimated Enrollment : 20 participants
Intervention Model : N/A
Masking: N/A
Primary Purpose: N/A
Official Title: Detection of Bacterial DNA and Collagen Metabolism in Acutely Ruptured Achilles Tendons
Actual Study Start Date: May 2019
Estimated Primary Completion Date: February 2021
Estimated Study Completion Date: July 2022
outcome measures
Primary Outcome Measures: 1. 14C concentration in acutely ruptured Achilles tendons [ Time Frame: The outcome measure will be assesed at time of surgery ]
14C concentration in biopsies from the ruptured part of the tendons and in the control biopsies proximal to the rupture are compared to the known historical values of atmospheric 14C to estimate the rate of collagen turnover. The values for turnover in the biopsies will be compared to the known rates of turnover in healthy tendons.
2. Heavy water (D2O) enrichment in acutely ruptured Achilles tendons [ Time Frame: The outcome measure will be assesed at time of surgery ]
2H isotope enrichment in the biopsies from the ruptured part of the tendons and in the control biopsies proximal to the rupture.
3. Fractional synthesis rate of protein at time of surgery in acutely ruptured Achilles tendons. [ Time Frame: The outcome measure will be assesed at time of surgery ]
The enrichment of the 15N marked proline tracer measured in the biopsies from the ruptured part of the tendons and in the control biopsies and compared to the enrichment of 15N marked proline in the blood. Based on that, the fractional synthesis rate of protein at the time of surgery is calculated.
4. Presence of bacteria in acutely ruptured Achilles tendons. [ Time Frame: The outcome measure will be assesed at time of surgery ]
Presence of bacterial DNA in the biopsies from the ruptured part of the tendons and in the control biopsies proximal to the rupture detected by 16s rDNA PCR
Biospecimen Retention: Samples With DNA
Biopsies from acutely ruptured Achilles tendonds will be taken, Two biopsies from the ruptured part of the tendon and two biopsies from the healthy tissue of the same tendon proximal to the rupture, as a control.

Eligibility Criteria
Ages Eligible for Study: 18 to 70 Years (Adult, Older Adult)
Sexes Eligible for Study: All
Accepts Healthy Volunteers: No
Criteria

Inclusion Criteria:

- Age 18-70 years

- Appointment in the Outpatients Department within 4 days after injury.

- Total Acute Achilles tendon rupture

- The patient must be able to speak and understand Danish.

- The patient must be able to give informed consent.

Exclusion Criteria:

- Rupture of the Achilles tendon either at the insertion on the calcaneus or at musculotendinous junction of the triceps surae.

- Previous rupture of the same Achilles tendon

- Undergone any surgery in the same region as the affected Achilles tendon.

- In medical treatment of diabetes.

- Present infection in the affected region.

- Contra-indication for surgery: severe arthrosclerosis with no palpable pulse in the foot, broken skin in the Achilles region of the injured leg.

- Inability to lie in prone position on the operating table.

- Rheumatoid arthritis or any other inflammatory disorder of the joints.

- Terminal illness or severe medical illness. ASA score higher than or equal to 3.


Contacts and Locations
Contacts

Contact: Allan Cramer +4560174294 allancramer94@gmail.com

Locations
Denmark Department of Orthopedic Surgery, Copenhagen University Hospital, Hvidovre Hvidovre
Sponsors and Collaborators
Copenhagen University Hospital, Hvidovre
Bispebjerg Hospital
Investigator
Study Chair : Kristoffer W Barfod, MD Copenhagen University Hospital, Hvidovre
More Information
Responsible Party : Copenhagen University Hospital, Hvidovre
ClinicalTrials.gov Identifier : NCT03931486     
Other Study ID Numbers : H-18010363
First Posted : April 30, 2019
Last Update Posted : July 14, 2020
Last Verified : July 2020
Individual Participant
Data (IPD) Sharing
Statement:
 
Plan to Share IPD: Undecided
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms :
Rupture