Midterm Survivorship and Complications of Total Knee Arthroplasty in Patients with Dwarfism

Abstract Background Dwarfism is associated with skeletal dysplasias and joint deformities that frequently result in osteoarthritis requiring treatment with total knee arthroplasty (TKA). These surgeries can be challenging due to alignment deformities, poor bone stock, and smaller components. This study aims to compare TKA implant survivorship and complications between dwarf and non-dwarf patients. Methods A retrospective case-control study was performed from 1997-2014 evaluating 115 TKAs in patients under the height threshold of 147.32cm. This cohort was compared to 164 patients of normal height, using propensity score weighting to balance gender, age, year of surgery, and comorbidities. Medical records were reviewed for demographics, surgical characteristics, and outcomes. Radiographic evaluation was performed to assess alignment, periprosthetic fractures, and loosening. All cases had 2-year minimum follow-up. Results The revision rate was 8.7% in dwarfs compared with 3.7% in controls (p=0.08). The 2-, 5-, and 10-year implant survivorship in dwarfs was 96.4%, 92.5%, and 90.2%, respectively; and 96.6%, 95.6%, and 94.8% for controls, respectively (p=0.24). Dwarfs underwent significantly more manipulations for arthrofibrosis (p=0.002). There was greater femoral (17.4% vs. 2.1%, p