Accuracy of Leg Length and Offset Restoration in Femoral Pinless Navigation Compared to Navigation Using a Fixed Pin during Total Hip Arthroplasty

Biomed Res Int. 2018 Jun 25:2018:1639840. doi: 10.1155/2018/1639840. eCollection 2018.

Abstract

Equalization of biomechanical differences is a major goal in total hip arthroplasty (THA). In the current study we compared the accuracy of restoring leg length and offset using imageless navigation with an osseous fixed pin to a femoral pinless device in 97 minimally invasive THAs through an anterolateral approach in the lateral decubitus position. Leg length and offset differences were evaluated on magnification-corrected radiographs by a blinded observer. A postoperative mean difference of -0.9 mm (95% CI -2.8 mm to 1.1 mm, p = 0.38) between pinless navigation and navigation with a fixed pin was observed for leg length and that of -2.4 mm (95% CI -3.9 mm to -0.9 mm, p = 0.002) was observed for offset, respectively. The number of patients with a residual difference below 5 mm after THA was higher if using a fixed pin than in pinless navigation for both leg length (98.2%, 54/55 to 50.0%, 21/42, p < 0.001) and offset (100.0%, 55/55 to 71.4%, 30/42, p < 0.001). Imageless navigation is a feasible method in intraoperative control of leg length and offset in minimally invasive THA. The use of pins fixed to the bone has a higher precision than pinless devices. This trial is registered with DRKS00000739.

MeSH terms

  • Aged
  • Arthroplasty, Replacement, Hip*
  • Female
  • Femur / anatomy & histology*
  • Hip Prosthesis
  • Humans
  • Male
  • Middle Aged
  • Prospective Studies
  • Reproducibility of Results
  • Surgery, Computer-Assisted