Elsevier

Injury

Volume 50, Issue 4, April 2019, Pages 962-965
Injury

Can the use of femoral notch view alone decrease measurement error of distal interlocking screws after retrograde femoral nailing

https://doi.org/10.1016/j.injury.2019.03.012Get rights and content

Highlights

  • Differentiating distal interlocking screw lengths on traditional imaging (AP/Notch/Tangential) is poor.

  • The addition of the femoral notch view with the traditional PA view can maximize a surgeon’s ability to detect prominent distal interlocking screws.

  • Careful intraoperative radiographic assessment with multiple views could decrease the need for symptomatic screw removal.

Abstract

Objectives

Determine if using different fluoroscopic views of the knee (Notch or Tangential) improves accuracy of screw lengths assessment compared to the standard posteroanterior (PA).

Participants and Methods: Orthopaedic surgeons at three ACGME-accredited residency programs were asked via survey to assess screw lengths on PA, femoral notch, and tangential radiographic views.

Results

Responders correctly identified screw length using PA, femoral notch, and medial tangential views at rates of 46.75%, 52.27%, and 44.37% respectively. Respondents detected overall screw length discrepancies most accurately using the femoral notch view (Odds Ratio 1.26; 95% confidence interval: 1.07–1.47; P < 0.005). There was no statistical difference between the residents and faculty cohort in ability to detect screw length discrepancy.

Conclusion

Differentiating distal interlocking screw lengths on traditional imaging (AP/Notch/Tangential) is poor. The femoral notch view significantly improves accuracy in radiographic determination of screw length. The femoral notch view should be used in conjunction with the traditional PA view to maximize sensitivity and specificity for detecting prominent screws.

Introduction

Knee pain following intramedullary nailing of the femur is not uncommon with its incidence as high as 86% and 37% with retrograde and antegrade approach respectively [[1], [2], [3], [4], [5], [6], [7], [8]]. The most common causes of knee pain from retrograde intramedullary nailing are related to soft tissue irritation often resulting from the protrusion of distal interlocking screws [3,6,7]. This often leads to additional surgical procedures to remove symptomatic implants leading to a significant healthcare and economic burden [9].

The posteroanterior (PA) view of the knee is often used to confirm final distal interlocking screw position. This technique is fraught with difficulties due to the trapezoidal shape of the distal femur, with the anterior surface being narrower than the posterior surface. As a result, screws that appear to be of appropriate length are in fact prominent. Imaging techniques other than PA imaging may help improve the accuracy of measurement however, little work has been conducted to assess alternative imaging. [10]

Improvement in the accuracy of screw placement has potential to decrease rates of symptomatic implant removal after retrograde femoral nailing. The purpose of this study was to determine if different fluoroscopic views of the knee (Notch or Tangential) could improve the accuracy of radiographic screw length assessment.

Section snippets

Cadaver preparation

Four cadaveric lower limb specimens (2 left, 2 right) were used to simulate retrograde femoral nailing surgical procedures. Cadaveric specimens were free from any history of trauma or deformity of the bony structure and soft tissues in the lower extremity. Using manufacturer recommended techniques, 4 retrograde femoral nails (T2 Retrograde Femoral Nail, Stryker, Kalamazoo, MI, USA) were inserted. Only the most distal interlock was utilized to ensure that the distal interlocking screw was placed

Results

Not all participants completed the survey. The resident cohort answered on average more questions than faculty, 33.91 ± 5.15 questions vs faculty 29.82 ± 11.81 questions (P < 0.016).

Respondents were able to detect overall screw length discrepancies most accurately using the femoral notch view compared to using the PA view (Odds Ratio [OR] 1.26; 95% confidence interval [CI]: 1.07–1.47; P < 0.005) (Table 2). When the images were stratified according to their corresponding screw length, our cohort

Discussion

Despite knee pain from prominent hardware in retrograde nailing being common, little research has focused on ways to prevent this complication. This is surprising, considering that up to 12–37% of patients elect to undergo hardware removal [8,13]. One would hope that good surgical technique with proper measurement and radiographic confirmation would help prevent this complication. However, measurement utilizing depth gauges can be confounded by interposed soft tissue. Intraoperatively

Conflict of interest statement

Boshen Liu, David Zuelzer, Jerad Allen, Shea Comadoll, and Eric Swart have nothing to disclose.

Joseph Hsu was a paid presented/speaker for Smith and Nephew. He is also a board or committee member of the Limb Lengthening Research Society. The terms of these arrangements have been reviewed and approved by Carolinas Medical Center in accordance with its policy on objectivity in research.

Paul Matuszewski receives research support from Stryker. The terms of this arrangement have been reviewed and

Acknowledgements

Cadavers and nails utilized in this investigation were provided in-kind by Stryker Orthopaedics.

References (14)

  • A.D. Toms et al.

    Intramedullary femoral nailing: removing the nail improves subjective outcome

    Injury

    (2002)
  • M. Hamaker et al.

    Radiographic predictors of symptomatic screw removal after retrograde femoral nail insertion

    Injury

    (2017)
  • L.B. Bone et al.

    Early versus delayed stabilization of femoral fractures. A prospective randomized study

    Orthop Trauma Dir

    (2006)
  • R.F. Ostrum et al.

    Retrograde intramedullary nailing of femoral diaphyseal fractures

    J Orthop Trauma

    (1998)
  • W.M. Ricci et al.

    Retrograde versus antegrade nailing of femoral shaft fractures

    J Orthop Trauma

    (2001)
  • R.J. Brumback et al.

    Intramedullary nailing of femoral shaft fractures. Part II: fracture-healing with static interlocking fixation

    J Bone Joint Surg Am

    (1988)
  • R.R. Gandhi et al.

    Optimal timing of femur fracture stabilization in polytrauma patients: a practice management guideline from the Eastern Association for the Surgery of Trauma

    J Trauma Acute Care Surg

    (2014)
There are more references available in the full text version of this article.

Cited by (0)

View full text