Trial Outcomes & Findings for Microbiome and Metagenome in Percutaneous Osseointegrated Prostheses (MMPOP) (NCT NCT02564432)

NCT ID: NCT02564432

Last Updated: 2020-02-19

Results Overview

To compare, within each participant, the Bacterial Community Type dynamics over time, we used Loess regression to visualize local (temporal) trends in the data. Specifically, it takes the scatter-plot of values (relative abundances, diversity indices) and uses smoothing to identify local trends in the data. As percentage RNA sequence reads were the measure of central tendency, measure of dispersion of the data was not possible to calculate.

Recruitment status

COMPLETED

Target enrollment

10 participants

Primary outcome timeframe

On Day 3 after first surgery and day 3 prior to and days, 3, 14 and week 6 and months 3, 6, 9 and 12 after second surgery.

Results posted on

2020-02-19

Participant Flow

Patients, who were recruited to participate in the early feasibility study of the percutaneous osseointegrated prosthesis (NCT02720159), were also recruited to participate in this study. Patients were transfemoral amputees selected from the VA patient registry

Participant milestones

Participant milestones
Measure
Stomal and Skin Microbiota
Unilateral transfemoral amputees, who were fitted with a single percutaneous osseointegrated prosthetic device, were included in this study. The microbiota of the stoma (the skin exit site through which the percutaneous post protrudes) was sampled at defined time points for 16S (Svedberg unit) rRNA (ribosomal ribonucleic acid) and followed for 12 months, after the Stage 2-surgery. Microbiota from each patient's healthy ipsilateral thigh skin were used as controls. Thus, each patient had an internal control at each sampling point.
Overall Study
STARTED
10
Overall Study
COMPLETED
8
Overall Study
NOT COMPLETED
2

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
POP 10 Patient Cohort
n=10 Participants
Patient who are fitted with POP devices
Age, Categorical
<=18 years
0 Participants
n=10 Participants
Age, Categorical
Between 18 and 65 years
9 Participants
n=10 Participants
Age, Categorical
>=65 years
1 Participants
n=10 Participants
Sex: Female, Male
Female
0 Participants
n=10 Participants
Sex: Female, Male
Male
10 Participants
n=10 Participants
Region of Enrollment
United States
10 Participants
n=10 Participants
Fitted with a percutaneous osseointegrated prosthesis
10 Number of patients
n=10 Participants

PRIMARY outcome

Timeframe: On Day 3 after first surgery and day 3 prior to and days, 3, 14 and week 6 and months 3, 6, 9 and 12 after second surgery.

Population: Microbiota from implant stoma and ipsilateral thigh skin.

To compare, within each participant, the Bacterial Community Type dynamics over time, we used Loess regression to visualize local (temporal) trends in the data. Specifically, it takes the scatter-plot of values (relative abundances, diversity indices) and uses smoothing to identify local trends in the data. As percentage RNA sequence reads were the measure of central tendency, measure of dispersion of the data was not possible to calculate.

Outcome measures

Outcome measures
Measure
Stoma Microbiota
n=10 Participants
Patients implanted with POP devices
Healthy Thigh Skin Microbiota
n=10 Participants
Patient's thigh skin with and without POP implants (which proved to be the same and the ipsilateral thigh skin was used for final analysis)
Bacterial Community Types as Determined by Percentage RNA Sequence Reads
Staphylococcus
3.4 Percentage RNA sequence reads
4.6 Percentage RNA sequence reads
Bacterial Community Types as Determined by Percentage RNA Sequence Reads
Streptococcus
4.7 Percentage RNA sequence reads
8.7 Percentage RNA sequence reads
Bacterial Community Types as Determined by Percentage RNA Sequence Reads
Corynebacterium
2.2 Percentage RNA sequence reads
24.0 Percentage RNA sequence reads

SECONDARY outcome

Timeframe: On Day 3 after first surgery and day 3 prior to and days, 3, 14 and week 6 and months 3, 6, 9 and 12 after second surgery.

Population: Ten unilateral transfemoral amputees with a percutaneous osseointegrated prosthetic docking system.

Times required to reach stable Bacterial Community Types (CT) after the Stage 2 surgery. Dirichlet multinomial mixture modeling was used to examine the heterogeneity and optimal number of the community compositions within each sample site. Often, skin samples clustered optimally to a single community type. Five community types (CT1-5) were identified: CT1 was defined by mixed communities of obligate anaerobes. CT2 was defined as those with median Shannon diversity index of \~4.5. CT3 was defined as the microbial community with the Shannon index of \~ 0.6 and dominated by Streptococcus. CT4 and CT5 were characterized by high relative abundances of Corynebacterium (median = 49%) and Staphylococcus (median = 34%), respectively. Patients, post-surgery, stabilized to one of CT1 - CT5 stomal microbiota.

Outcome measures

Outcome measures
Measure
Stoma Microbiota
n=10 Participants
Patients implanted with POP devices
Healthy Thigh Skin Microbiota
Patient's thigh skin with and without POP implants (which proved to be the same and the ipsilateral thigh skin was used for final analysis)
Time to Equilibrium of the Bacterial Community Types Over the Duration of the Study
2.7 Months
Standard Deviation 2.5

Adverse Events

POP 10 Patient Cohort

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

James Peter Beck

Department of Veterans Affairs

Phone: 801-231-6309

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place