Novel Method for Ensuring Leg Length in Total Hip Arthroplasty

Abstract

Despite the overwhelming clinical success of total hip arthroplasty, complications such as leg-length discrepancy can be a significant cause of functional impairment and patient dissatisfaction. Multiple intraoperative techniques are available for measuring femoral limb length; however, many require additional invasive hardware and those that do not are less accurate at measuring limb length. This article introduces a novel, noninvasive intraoperative technique that quickly and accurately measures limb length and prevents postoperative leg-length discrepancy.The authors' method relies on the accurate reproduction of a line perpendicular to the femoral axis near the proximal aspect of the greater trochanter intraoperatively and during preoperative planning and requires minor modifications to the instrumentation used. A narrow slot for the placement of a guide plate was machined into a standard trial head 37° from the axis of the neck for use with a high offset 127° Secur-Fit PLUS stem and 42° from the axis of the neck for use with a standard offset 132° Secur-Fit stem (Stryker Orthopaedics, Kalamazoo, Michigan). Once a broach is securely seated, a trial neck, slotted trial head, and guide plate are assembled and the distance from the guide plate to the proximal tip of the greater trochanter is compared with the preoperative planning measurements to assess the stem position.A retrospective radiographic analysis of 31 consecutive primary total hip arthroplasty using this technique showed the mean postoperative leg-length discrepancy to be 2.18±6.08 mm. This method is an additional tool for the arthroplasty surgeon's armamentarium to ensure accurate leg-length restoration.

Intraoperative measurement of limb lengthening during total hip arthroplasty

“…These methods can be divided into four main categories: (1) Based on the preoperative templating to define the correct neck cut, the correct neck length of the femoral component (in case of a modular head) or the correct depth of insertion of the femoral component (by measuring the distance of the tip of the greater trochanter to the shoulder of the femoral component),5678 (2) based on the usage of a standard pelvic reference point and of a femoral reference point, and measurement of the distance of these two points as the limb length changes intraoperatively [the marking of the pelvic reference point and the measurement can be performed with the aid of calipers,91011121314151617 bented K-wire,18 suture (tied in the skin, in a K-wire, or in a pin),19 Steinman pin in the infracotyloid groove or screw above the superior acetabular rim,2021 (3) based on clinical tests intraoperatively such as the shuck test, the drop kick test, and the leg-to-leg comparison,152223 and (4) based on navigation system's measurements 16242526. In addition, some other techniques have been described, such as measuring the gap between the tenotomy limb edges of the abductor musculotendinous insertion on the greater trochanter15 or evaluating the level of the center of the head in relation to the tip of the greater trochanter with the aid of a plate in a femoral head slot 27…”

Clinical Application of Hip Joint Anatomical CT Digital Measurement and Correlation Analysis

“…The fuzzy concept of ne anatomical parameter indices has increased the error rate of surgeries and postoperative complications. Maratt et al [4] conducted a follow-up study of 120 post-THA patients in 2012 and found that 30% of patients had unequal lower limb lengths, poor hip joint function, and some experienced limping symptoms.…”