An Intelligent Instrument for Improved Leg Length and Hip Offset Accuracy in Total Hip Arthroplasty

Intellijoint HIP Limited Release Trial: An Intelligent Instrument for Improved Leg Length and Hip Offset Accuracy in Total Hip Arthroplasty

Leg length discrepancies following total hip arthroplasty have been associated with nerve palsies, gait abnormalities, and lower back pain. Leg length discrepancies are related to poorer functional outcomes and patient dissatisfaction. Failure to restore femoral offset following total hip arthroplasty has been linked to decreased range of motion and abductor muscle strength, impingement, limping, higher dislocation rates, increased polyethylene wear, and loosening of implants. Computer navigation has shown to improve the accuracy of leg length and hip offset during total hip arthroplasty. The investigators research objective is to prove the accuracy of the Intellijoint HIP™ system for determining leg length and hip offset. The investigators hypothesis was that Intellijoint HIP™, an imageless intraoperative intelligent instrument, could improve the accuracy of leg length and hip offset during primary total hip arthroplasty. The investigators plan to study this hypothesis in humans by comparing the leg length and hip offset discrepancies produced with Intellijoint HIP™ to the standard at the investigators institution, which is a pin and outrigger system.

Patient's will have their leg length and hip offset determined intraoperatively using Intellijoint HIP.

Control patients will have their leg length and hip offset determined intra-operatively using the standard at Mount Sinai Hospital, which is a pin and outrigger system.

Intellijoint HIP is an intra-operative, imageless intelligent instrument used to provide real-time information to surgeons about leg length and hip offset changes during total hip replacement surgery.

The outrigger is a pin and caliper device that is used to assess leg length and offset during total hip arthroplasty. It is the current standard of care at Mount Sinai Hospital.

Standard post-operative anteroposterior pelvis radiographs will be used to assess the leg length discrepancy

Standard post-operative anteroposterior pelvis radiographs will be used to assess the hip offset restoration

We will measure the skin-to-closure time for each surgery to assess additional time, if any, added to procedure when using PelvAssist.

Inclusion Criteria: Any patient who is undergoing a primary total hip arthroplasty at Mount Sinai Hospital. Exclusion Criteria: Pre-operative flexion contracture >30°, infection, or inability to achieve rigid fixation of instruments intra-operatively.