Trial Outcomes & Findings for Comparison of High Flex and Standard Rotating Platform Total Knee Arthroplasty (TKA) (NCT NCT01176292)

NCT ID: NCT01176292

Last Updated: 2020-11-23

Results Overview

Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 142 participants
• Primary outcome timeframe: Preoperative, 4-6 weeks
• Results posted on: 2020-11-23

Participant Flow

Subject enrollment began August 2007 and ended April 2009, with a total of 142 patients enrolled at an orthopaedic clinic.

Participant milestones

Measure	Rotating Platform High-Flex Cruciate Substituting TKA	Rotating Platform Cruciate Substituting TKA
Overall Study STARTED	71	71
Overall Study COMPLETED	66	62
Overall Study NOT COMPLETED	5	9

Reasons for withdrawal

Measure	Rotating Platform High-Flex Cruciate Substituting TKA	Rotating Platform Cruciate Substituting TKA
Overall Study Lost to Follow-up	2	4
Overall Study Adverse Event	1	1
Overall Study Physician Decision	0	2
Overall Study Has not scheduled one-year visit yet	2	2

Baseline Characteristics

Comparison of High Flex and Standard Rotating Platform Total Knee Arthroplasty (TKA)

Baseline characteristics by cohort

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=71 Participants	Rotating Platform Cruciate Substituting TKA n=71 Participants	Total n=142 Participants Total of all reporting groups
Age, Continuous	65 years STANDARD_DEVIATION 7 • n=5 Participants	62 years STANDARD_DEVIATION 7 • n=7 Participants	64 years STANDARD_DEVIATION 7 • n=5 Participants
Sex: Female, Male Female	37 Participants n=5 Participants	44 Participants n=7 Participants	81 Participants n=5 Participants
Sex: Female, Male Male	34 Participants n=5 Participants	27 Participants n=7 Participants	61 Participants n=5 Participants

PRIMARY outcome

Timeframe: Preoperative, 4-6 weeks

Population: All subjects with available data at the preoperative and 4-6 week intervals.

Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=70 Participants	Rotating Platform Cruciate Substituting TKA n=68 Participants
Clinical Flexion Clinical flexion - preoperative	119.1 degrees Standard Deviation 13.2	120.3 degrees Standard Deviation 11.2
Clinical Flexion Clinical flexion - 4 week	112.0 degrees Standard Deviation 12.7	111.3 degrees Standard Deviation 15.3

PRIMARY outcome

Timeframe: 4-6 months

Population: All subjects with available data at the 4-6 month interval.

Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=70 Participants	Rotating Platform Cruciate Substituting TKA n=65 Participants
Clinical Flexion	122.5 degrees Standard Deviation 8.6	121.3 degrees Standard Deviation 9.6

PRIMARY outcome

Timeframe: 1 year

Population: All subjects with available data at the 1-year interval.

Maximum, passive flexion and extension of the operated knee joint in the supine position will be measured and recorded using a long goniometer.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=66 Participants	Rotating Platform Cruciate Substituting TKA n=62 Participants
Clinical Flexion	124.2 degrees Standard Deviation 8.7	124.0 degrees Standard Deviation 10.3

SECONDARY outcome

Timeframe: preoperative, 4-6 weeks

Population: All subjects with available data at the preoperative and 4-6 week intervals.

Lateral radiographs of the knee will be taken with the patient supine with maximal passive knee flexion. Flexion will then be measured directly from these radiographs.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=70 Participants	Rotating Platform Cruciate Substituting TKA n=68 Participants
Radiographic Flexion preoperative	116.8 degrees Standard Deviation 14.1	116.6 degrees Standard Deviation 15.5
Radiographic Flexion 4-6 weeks	104.7 degrees Standard Deviation 16.3	102.1 degrees Standard Deviation 16.4

SECONDARY outcome

Timeframe: 1 year

Population: All subjects with available data at the 1-year interval.

Lateral radiographs of the knee will be taken with the patient supine with maximal passive knee flexion. Flexion will then be measured directly from these radiographs.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=66 Participants	Rotating Platform Cruciate Substituting TKA n=62 Participants
Radiographic Flexion	117.6 degrees Standard Deviation 11.1	117.9 degrees Standard Deviation 11.6

SECONDARY outcome

Timeframe: 1 year

Population: All subjects with available KSS data at the 1-year interval.

A standard clinical evaluation system for reporting results for patients undergoing total knee replacement. The minimum score is 0 and the highest score is 100. A higher score represents a better outcome.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=66 Participants	Rotating Platform Cruciate Substituting TKA n=62 Participants
Knee Society Score (KSS) Clinical KSS	95.0 score Standard Deviation 8.4	94.9 score Standard Deviation 8.3
Knee Society Score (KSS) Functional KSS	87.7 score Standard Deviation 19.9	90.9 score Standard Deviation 16.0

SECONDARY outcome

Timeframe: 1 year

Population: All subjects with available Oxford Knee Score data at the 1-year interval.

A patient reported questionnaire for assessing the outcome of knee surgery. The minimum score is 0 and the maximum score is 48. A higher score represents a better outcome.

Outcome measures

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=59 Participants	Rotating Platform Cruciate Substituting TKA n=57 Participants
Oxford Knee Score	41.0 score Standard Deviation 6.5	41.8 score Standard Deviation 7.4

Adverse Events

Rotating Platform High-Flex Cruciate Substituting TKA

Serious events: 7 serious events

Other events: 9 other events

Deaths: 0 deaths

Rotating Platform Cruciate Substituting TKA

Serious events: 4 serious events

Other events: 3 other events

Deaths: 0 deaths

Serious adverse events

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=71 participants at risk	Rotating Platform Cruciate Substituting TKA n=71 participants at risk
Infections and infestations infection	1.4% 1/71 • Number of events 1 • 1 year follow-up Collected according to standard protocol.	1.4% 1/71 • Number of events 1 • 1 year follow-up Collected according to standard protocol.
Musculoskeletal and connective tissue disorders stiffness	2.8% 2/71 • Number of events 2 • 1 year follow-up Collected according to standard protocol.	2.8% 2/71 • Number of events 2 • 1 year follow-up Collected according to standard protocol.
Musculoskeletal and connective tissue disorders patellar fracture	1.4% 1/71 • Number of events 1 • 1 year follow-up Collected according to standard protocol.	0.00% 0/71 • 1 year follow-up Collected according to standard protocol.
Musculoskeletal and connective tissue disorders quadriceps tendon rupture	1.4% 1/71 • Number of events 1 • 1 year follow-up Collected according to standard protocol.	0.00% 0/71 • 1 year follow-up Collected according to standard protocol.
Musculoskeletal and connective tissue disorders symptomatic patellar crepitus	2.8% 2/71 • Number of events 2 • 1 year follow-up Collected according to standard protocol.	1.4% 1/71 • Number of events 1 • 1 year follow-up Collected according to standard protocol.

Other adverse events

Measure	Rotating Platform High-Flex Cruciate Substituting TKA n=71 participants at risk	Rotating Platform Cruciate Substituting TKA n=71 participants at risk
Musculoskeletal and connective tissue disorders postoperative pain	0.00% 0/71 • 1 year follow-up Collected according to standard protocol.	2.8% 2/71 • Number of events 2 • 1 year follow-up Collected according to standard protocol.
Musculoskeletal and connective tissue disorders patellar crepitus	12.7% 9/71 • Number of events 9 • 1 year follow-up Collected according to standard protocol.	1.4% 1/71 • Number of events 1 • 1 year follow-up Collected according to standard protocol.

Additional Information

Dr. William Hamilton

Anderson Orthopaedic Research Institute

Phone: 703-619-4411

Email: research@aori.org

Results disclosure agreements

• Principal investigator is a sponsor employee Any paper drafted by authors regarding project results should be sent to sponsor at least 30 days before being submitted for publication. An abstract should be sent to the sponsor at least 10 days before being submitted. The sponsor will inform the authors of any changes deemed necessary to preserve the confidentiality of proprietary information or to insure scientific accuracy.
• Publication restrictions are in place

Restriction type: OTHER