Trial Outcomes & Findings for Knee Arthroplasty Performed With Conventional and Customized Instrumentation (NCT NCT01124305)

NCT ID: NCT01124305

Last Updated: 2013-12-18

Results Overview

Time elapsed from skin incision to wound closure (in seconds)

• Recruitment status: COMPLETED
• Study phase: PHASE4
• Target enrollment: 70 participants
• Primary outcome timeframe: 1 day
• Results posted on: 2013-12-18

Participant Flow

Patients were recruited at a suburban orthopaedic clinic setting between June 2010 and Sept 2011.

Patients were excluded if their medical insurance did not cover a leg CT scan or if there was any metal in their leg.

Participant milestones

Measure	Traditional Instrumentation Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.
Overall Study NOT COMPLETED	8	10
Overall Study STARTED	34	36
Overall Study COMPLETED	26	26

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Knee Arthroplasty Performed With Conventional and Customized Instrumentation

Baseline characteristics by cohort

Measure	Traditional Instrumentation n=34 Participants Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation n=36 Participants Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.	Total n=70 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	11 Participants n=5 Participants	11 Participants n=7 Participants	22 Participants n=5 Participants
Age, Categorical >=65 years	23 Participants n=5 Participants	25 Participants n=7 Participants	48 Participants n=5 Participants
Age, Continuous	71.3 years STANDARD_DEVIATION 12.1 • n=5 Participants	69.2 years STANDARD_DEVIATION 8.5 • n=7 Participants	70.1 years STANDARD_DEVIATION 10.0 • n=5 Participants
Sex: Female, Male Female	23 Participants n=5 Participants	19 Participants n=7 Participants	42 Participants n=5 Participants
Sex: Female, Male Male	11 Participants n=5 Participants	17 Participants n=7 Participants	28 Participants n=5 Participants
Region of Enrollment United States	34 participants n=5 Participants	36 participants n=7 Participants	70 participants n=5 Participants

PRIMARY outcome

Timeframe: 1 day

Population: per protocol

Time elapsed from skin incision to wound closure (in seconds)

Outcome measures

Measure	Traditional Instrumentation n=26 Participants Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation n=26 Participants Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.
Length of Surgery	3447.19 seconds Standard Deviation 297.68	3707.19 seconds Standard Deviation 348.26

SECONDARY outcome

Timeframe: 1 day

Population: per protocol

surgical exposure, tibial alignment and resection, femoral distal cut, extension gap balancing, sizing the femur, 4 finishing femoral cuts, posterior releases, patellar resection, trial components, tibial tray preparation, cleanup/ prep for cement, cementing femur, cementing tibia, cementing patella, and closure

Outcome measures

Measure	Traditional Instrumentation n=26 Participants Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation n=26 Participants Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.
Length of Each Surgical Step (in Seconds) Exposure	297.19 seconds Standard Deviation 54.87	318.38 seconds Standard Deviation 64.00
Length of Each Surgical Step (in Seconds) Tibial Alignment and Resection	111.77 seconds Standard Deviation 37.67	129.73 seconds Standard Deviation 29.47
Length of Each Surgical Step (in Seconds) Femoral Distal Cut	95.19 seconds Standard Deviation 19.5	170.46 seconds Standard Deviation 86.91
Length of Each Surgical Step (in Seconds) Extension Gap Balancing	89.77 seconds Standard Deviation 73.88	77.88 seconds Standard Deviation 59.35
Length of Each Surgical Step (in Seconds) Sizing the Femur	41.58 seconds Standard Deviation 11.70	21.46 seconds Standard Deviation 42.01
Length of Each Surgical Step (in Seconds) 4 Finishing Femoral Cuts	135.54 seconds Standard Deviation 35.67	186.96 seconds Standard Deviation 89.69
Length of Each Surgical Step (in Seconds) Posterior Releases	225.42 seconds Standard Deviation 46.91	223.81 seconds Standard Deviation 51.68
Length of Each Surgical Step (in Seconds) Patellar Resection	133.04 seconds Standard Deviation 27.51	136.31 seconds Standard Deviation 30.41
Length of Each Surgical Step (in Seconds) Trial Components	247.92 seconds Standard Deviation 64.76	253.42 seconds Standard Deviation 78.78
Length of Each Surgical Step (in Seconds) Tibial Tray Preparation	71.85 seconds Standard Deviation 24.20	67.54 seconds Standard Deviation 24.38
Length of Each Surgical Step (in Seconds) Cleanup/ Prepare for Cement	206.46 seconds Standard Deviation 59.32	196.00 seconds Standard Deviation 53.16
Length of Each Surgical Step (in Seconds) Cementing Femur	127.15 seconds Standard Deviation 22.86	141.65 seconds Standard Deviation 22.55
Length of Each Surgical Step (in Seconds) Cementing Tibia	77.77 seconds Standard Deviation 16.99	83.62 seconds Standard Deviation 18.47
Length of Each Surgical Step (in Seconds) Cementing Patella	102.65 seconds Standard Deviation 45.14	97.77 seconds Standard Deviation 22.98
Length of Each Surgical Step (in Seconds) Closure	1221.62 seconds Standard Deviation 140.27	1246.69 seconds Standard Deviation 133.82

SECONDARY outcome

Timeframe: 1 day

Population: per protocol

Outcome measures

Measure	Traditional Instrumentation n=26 Participants Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation n=26 Participants Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.
Number of Instrument Trays Required	7.3 number of trays Standard Deviation 0.69	2.5 number of trays Standard Deviation 1.14

SECONDARY outcome

Timeframe: 4 months

Population: All participants were x-rayed postoperatively to measure the mechanical axis of the leg in degrees.

Alignment is measured on 4 month postoperative radiograph in degrees. The goal is a mechanical axis between and femur and tibia of 0 degrees. Varus alignment ("bow-legged") is shown as a negative number in degrees away from 0. Valgus alignment ("Knock-kneed") is expressed as a positive number in degrees away from 0.

Outcome measures

Measure	Traditional Instrumentation n=26 Participants Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation n=26 Participants Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.
Limb Alignment (Mechanical Axis)	0.7 degrees varus(-) or valgus(+) Interval -5.9 to 7.6	0.3 degrees varus(-) or valgus(+) Interval -6.8 to 6.4

Adverse Events

Traditional Instrumentation

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Customized Patient Instrumentation

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Measure	Traditional Instrumentation n=26 participants at risk Control group: Cases performed with traditional surgical instruments	Customized Patient Instrumentation n=26 participants at risk Experimental group: Cases performed with custom instruments specifically made for each patient using pre-op CT scans.
Musculoskeletal and connective tissue disorders Knee stiff	3.8% 1/26 • Number of events 1 • 4 months This is a study of surgical instruments, therefore the focus would be on adverse events occurring during surgery. All patients were followed for 4 months, so we also able to capture adverse events in the short-term postoperative period.	0.00% 0/26 • 4 months This is a study of surgical instruments, therefore the focus would be on adverse events occurring during surgery. All patients were followed for 4 months, so we also able to capture adverse events in the short-term postoperative period.

Additional Information

Knee Project Director

AORI

Phone: 7036194423

Email: nparks@aori.org

Results disclosure agreements

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