Anterior Knee Pain Between Unisex Knee Prosthesis VS Gender Specific Knee Prosthesis Following MIS TKA
Condition: Osteo Arthritis Knee; Knee Pain Chronic
MeSH terms: Osteoarthritis; Osteoarthritis, Knee
Study type: Interventional

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.
    

Intervention name(s): Gender 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
Intervention type(s): Procedure
Intervention description(s): 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.
Intervention MeSH terms: Cimetidine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: anterior knee pain; gender knee prosthesis; patellar tracking; unisex knee prosthesis; total knee arthroplasty; patellar resurfacing