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Anterior Knee Pain Between Unisex Knee Prosthesis VS Gender Specific Knee Prosthesis Following MIS TKA

The Incidence of Anterior Knee Pain Between Unisex Knee Prosthesis and Gender Specific Knee Prosthesis Following Minimally Invasive Surgery Total Knee Arthroplasty: A Randomized Controlled Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05045651
Enrollment
80
Registered
2021-09-16
Start date
2014-08-01
Completion date
2018-12-01
Last updated
2021-09-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Knee Pain Chronic, Osteo Arthritis Knee

Keywords

anterior knee pain, gender knee prosthesis, patellar tracking, unisex knee prosthesis, total knee arthroplasty, patellar resurfacing

Brief summary

Unisex knee prosthesis and patient specific knee prosthesis has the same anterior knee pain and patellar tracking

Detailed description

Background:The anterior knee pain (AKP) is one of major problem of TKA. The incidence of anterior knee after TKA was 4% to 49%. The cause of AKP after TKA from surgical technique errors including joint line elevation, instability, malalignment of prosthesis, and maltracking of patella. However, AKP still has presented even high volume surgeon that prosthesis had good alignment and good stability, one of the risk factor is female. Due to female has higher Q-angle, greater anteroposterior (AP)/mediolateral(ML) ratio, smaller anterior condyle, and trochlea has higher degree of valgus angle than male. Therefore, female should has AKP even surgery with good surgical technique. The gender specific knee prosthesis was design for female to restore Q-angle, reduce anteroposterior (AP)/mediolateral(ML) ratio for reducing overhang of femoral component, increase valgus angle of trochlea groove, and reduce thickness of anterior part of prosthesis for prevention overstuff with patella. For these reasons, the gender specific knee prosthesis should reduce AKP and improve patellar tracking in female. And there is no study to compare AKP and patellar tracking between Unisex knee prosthesis and gender specific knee prosthesis following minimally invasive surgery (MIS) TKA. Investigators asked whether AKP and patellar tracking differ between unisex knee prosthesis and gender specific knee prosthesis following MIS TKA with patellar resurfacing. Methods:The participants were randomized into 2 groups (Gp) with computer program to make a list of random numbers of participant. Gp1 was gender specific knee prosthesis; consisted of 40 participants (40 knees) and Gp2 was unisex knee prosthesis; consisted of 40 participants (40 knees). The sample size was calculate base on anterior knee pain after TKA with a risk difference of 27% (3% versus 20%) (1,3). The 40 participants from each group would have 90% power at the 5% significant level. Patrticipants were follow up at 2 wks, 6 wks, 3 mo, 6mo, 1 year and 2 years. At each follow up, the % anterior knee pain, VAS for anterior knee pain were record. The knee society score also was recorded and compared between two group. All participants were operated with same surgeon and same instrumentation.

Interventions

PROCEDUREGender Solution®posterior stabilized NexGen® LPS Hi-Flex; Zimmer Biomet, Inc, Warsaw, IN, USA and standard posterior stabilized NexGen® LPS Hi-Flex; Zimmer Biomet, Inc, Warsaw, IN, USA

gender specific knee prosthesis:design for female to restore Q-angle, reduce anteroposterior (AP)/mediolateral(ML) ratio for reducing overhang of femoral component, increase valgus angle of trochlea groove, and reduce thickness of anterior part of prosthesis for prevention overstuff with patella. The standard TKA or unisex knee prosthesis was design for female and male.

Sponsors

Thammasat University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
FEMALE
Age
50 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

Aymptomatic knee OA with * varus deformity \< 30 degrees * range of motion \> 90 degrees * flexion contracture \< 20 degrees * recurvatum \< 20 degrees

Exclusion criteria

* gout * postraumatic arthritis * osteonecrosis of knee * inflammatory joint disease

Design outcomes

Primary

MeasureTime frameDescription
anterior knee pain4 yearsVisual analog scale for pain ( 0= no pain to 10= maximum pain), incidence for anterior knee pain (percent)
patellar tracking4 yearspatellar tilt \> 5 degrees and/or patellar shift\> 5 mm= patellar maltracking

Secondary

MeasureTime frameDescription
clinical outcome score4 yearsknee society score (0-20= poor outcomes, 21-40=fair outcomes, 41-60= good outcomes, 61-80= very good outcomes, 81-100= excellent outcome)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026