Trial Outcomes & Findings for A Safety Follow Up Study in Australian Subjects Implanted With the SMF Short Modular Femoral Stem Hip System (NCT NCT03646513)

Results Overview

All participants at Baseline and every three years afterwards up to 20 years will have whole blood collected for metal ion testing of whole blood cobalt (Co) and chromium (Cr). Symptomatic participants with pain, swelling, and/or functional limitations if assessed by the Principal Investigator to be related to the implant will have whole blood collected for metal ion testing of cobalt and chromium annually.

Recruitment status

TERMINATED

Target enrollment

4 participants

Primary outcome timeframe

Baseline to Study Completion, up to 20 years

Results posted on

2024-03-19

Participant Flow

Participants were recruited at a single study site according to the study inclusion and exclusion criteria from 14 February 2019 until early termination of the study on 12 March 2020.

Study was prematurely terminated prior to any participants completing follow-up visits.

Participant milestones

Participant milestones
Measure	SMF Short Modular Femoral Stem Implanted Subjects Subjects who have been implanted with the SMF Short Modular Femoral Stem for primary total hip arthroplasty. SMF Short Modular Femoral Hip System: Primary Total Hip Arthroplasty with SMF Short Modular Femoral Stem Hip System.
Overall Study STARTED	4
Overall Study COMPLETED	0
Overall Study NOT COMPLETED	4

Reasons for withdrawal

Reasons for withdrawal
Measure	SMF Short Modular Femoral Stem Implanted Subjects Subjects who have been implanted with the SMF Short Modular Femoral Stem for primary total hip arthroplasty. SMF Short Modular Femoral Hip System: Primary Total Hip Arthroplasty with SMF Short Modular Femoral Stem Hip System.
Overall Study Premature study termination	4

Baseline Characteristics

A Safety Follow Up Study in Australian Subjects Implanted With the SMF Short Modular Femoral Stem Hip System

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	SMF Short Modular Femoral Stem Implanted Subjects n=4 Participants Subjects who have been implanted with the SMF Short Modular Femoral Stem for primary total hip arthroplasty. SMF Short Modular Femoral Hip System: Primary Total Hip Arthroplasty with SMF Short Modular Femoral Stem Hip System.
Age, Continuous	59.5 years STANDARD_DEVIATION 59.0 • n=5 Participants
Sex: Female, Male Female	2 Participants n=5 Participants
Sex: Female, Male Male	2 Participants n=5 Participants
Race/Ethnicity, Customized Race · White	3 Participants n=5 Participants
Race/Ethnicity, Customized Race · Asian	1 Participants n=5 Participants
Region of Enrollment Australia	4 participants n=5 Participants
Body Mass Index (BMI)	30.3 kg/m^2 STANDARD_DEVIATION 28.0 • n=5 Participants

PRIMARY outcome

Timeframe: Baseline to Study Completion, up to 20 years

Population: Participants enrolled in the study with available data at the given time point for the outcome specified. Study prematurely terminated prior to any follow-up visits. Therefore, only baseline information was available.

All participants at Baseline and every three years afterwards up to 20 years will have whole blood collected for metal ion testing of whole blood cobalt (Co) and chromium (Cr). Symptomatic participants with pain, swelling, and/or functional limitations if assessed by the Principal Investigator to be related to the implant will have whole blood collected for metal ion testing of cobalt and chromium annually.

Outcome measures

Outcome measures
Measure	SMF Short Modular Femoral Stem Implanted Subjects n=4 Participants Subjects who have been implanted with the SMF Short Modular Femoral Stem for primary total hip arthroplasty. SMF Short Modular Femoral Hip System: Primary Total Hip Arthroplasty with SMF Short Modular Femoral Stem Hip System.
Metal Ion Level Baseline: Cobalt (Co)	115.0 Nanomoles per litre (nmol/L) Standard Deviation 118.0
Metal Ion Level Baseline: Chromium (Cr)	55.8 Nanomoles per litre (nmol/L) Standard Deviation 55.5

PRIMARY outcome

Timeframe: Baseline to study completion, up to 20 years

Population: Participants enrolled in the study with available data at the given time point for the outcome specified. Study prematurely terminated prior to any follow-up visits. Therefore, only baseline information was available.

Number of participants with whole blood cobalt (Co) and/or chromium (Cr) \> 7 ppb (Yes/No). Participants as 'Yes' to Co and/or Cr will have Metal Artifact Reduction Sequence (MARS) Magnetic Resonance Imaging (MRI) performed (or Computerized tomography (CT) if MRI is contraindicated). This is used to detect pseudotumors, abductor muscle atrophy, and tendinous pathology in patients with painful metal-on-metal (MOM) hip arthroplasty.

Outcome measures

Outcome measures
Measure	SMF Short Modular Femoral Stem Implanted Subjects n=4 Participants Subjects who have been implanted with the SMF Short Modular Femoral Stem for primary total hip arthroplasty. SMF Short Modular Femoral Hip System: Primary Total Hip Arthroplasty with SMF Short Modular Femoral Stem Hip System.
Number of Participants With Cobalt (Co) and Chromium (Cr) Metal Ions > 7 Parts-Per-Billion (Ppb) Baseline: Cobalt (Co) · Yes	2 Participants
Number of Participants With Cobalt (Co) and Chromium (Cr) Metal Ions > 7 Parts-Per-Billion (Ppb) Baseline: Cobalt (Co) · No	2 Participants
Number of Participants With Cobalt (Co) and Chromium (Cr) Metal Ions > 7 Parts-Per-Billion (Ppb) Baseline: Chromium (Cr) · Yes	0 Participants
Number of Participants With Cobalt (Co) and Chromium (Cr) Metal Ions > 7 Parts-Per-Billion (Ppb) Baseline: Chromium (Cr) · No	4 Participants

SECONDARY outcome

Timeframe: Study Completion, up to 20 years

Population: Study prematurely terminated prior to any follow-up visits.

Number of participants with a revision of any component of the SMF Short Modular Femoral Stem for any reason as a result of an adverse event. Revisions captured at any time during the study duration (up to 20 years) from the point of informed consent signing.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Baseline to study completion, up to 20 years

Population: Study prematurely terminated prior to any follow-up visits.

Standard of Care Radiographic Assessment for loosening indicated by radiolucencies \> 2 millimeters (mm). In a cemented arthroplasty, this lucency at the bone-cement interface indicates the formation of a fibrous membrane (representing the lucency). Periprosthetic lucencies wider than 2 mm and/or progressive lucencies are signs of abnormality.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Baseline to study completion, up to 20 years

Population: Study prematurely terminated prior to any follow-up visits.

Number of participants with evidence of surface wear (Yes/No) as indicated by early osteolysis, implant migration, or other clinical or radiographic abnormalities such as pseudo tumors or corrosion.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Baseline to study completion, up to 20 years

Population: Participants enrolled in the study with available data at the given time point for the outcome specified. Study prematurely terminated prior to any follow-up visits. Therefore, only baseline information was available.

The HOOS JR. questionnaire consists of 6 questions. These focus on 3 categories: joint pain, stiffness and function in daily living. The HOOS JR. questionnaire, allows patients to rate each activity by indicating the amount of pain or disability they experience while carrying them out. Raw scores are added up and then converted to an interval score (0-100) using an interval table. The final interval score represents a patients total joint disability where 0 corresponds to total joint disability (i.e., worse outcome) and 100 is perfect joint health (i.e., best outcome).

Outcome measures

Outcome measures
Measure	SMF Short Modular Femoral Stem Implanted Subjects n=4 Participants Subjects who have been implanted with the SMF Short Modular Femoral Stem for primary total hip arthroplasty. SMF Short Modular Femoral Hip System: Primary Total Hip Arthroplasty with SMF Short Modular Femoral Stem Hip System.
The Hip Osteoarthritis Outcomes Score Junior (HOOS JR) Questionnaire Baseline	100 score on a scale Standard Deviation 0

Adverse Events

SMF Short Modular Femoral Stem Implanted Subjects

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

Andrew Copey

Smith+Nephew, Inc.

Phone: +61.490.503.157

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place