Knee Surgery, Sports Traumatology, Arthroscopy

, Volume 22, Issue 3, pp 543–549

Non-anatomical capsular closure of a standard parapatellar knee arthrotomy leads to patellar maltracking and decreased range of motion: a cadaver study

Authors

    • Department of Orthopaedic SurgeryWake Forest School of Medicine
    • The Neuroscience ProgramWake Forest University Graduate School of Arts and Sciences
  • Thorsten M. Seyler
    • Department of Orthopaedic SurgeryWake Forest School of Medicine
  • Jason J. Halvorson
    • Department of Orthopaedic SurgeryWake Forest School of Medicine
  • Anthony C. SantagoII
    • Department of Biomedical EngineeringWake Forest School of Medicine
    • School of Biomedical Engineering and SciencesVirginia Tech-Wake Forest University
  • Jason E. Lang
    • Department of Orthopaedic SurgeryWake Forest School of Medicine
Knee

DOI: 10.1007/s00167-013-2369-3

Cite this article as:
Plate, J.F., Seyler, T.M., Halvorson, J.J. et al. Knee Surg Sports Traumatol Arthrosc (2014) 22: 543. doi:10.1007/s00167-013-2369-3

Abstract

Purpose

A parapatellar approach disrupts the medial soft tissue stabilizers of the patella. We hypothesized that soft tissue realignment during arthrotomy closure of native cadaveric knees influences patellar kinematics leading to decreased range of motion.

Methods

Parapatellar arthrotomy was performed in seven native human cadaveric knees that did not contain arthroplasty components. Capsular closure was performed with figure-of-eight sutures in five different positions for each specimen. The capsule was closed anatomically, and then shifted 1.5 or 3 cm distal, or 1.5 or 3 cm proximal relative to surgical markings of the patellar poles. In each closure position, real-time patellar kinematics and range of motion were recorded using a navigation system with patellar tracking function.

Results

Maximum knee flexion was significantly reduced with closure shifted 3 cm proximal (133° ± 8.2°, p < 0.001) or distal (139° ± 6.4°, p < 0.05) compared to anatomical closure (147° ± 4.1°). All closure positions significantly influenced patellar rotation at 45°, 90°, and 120° of flexion (p < 0.001). Closure 1.5 or 3 cm distal increased lateral patellar shift relative to the mechanical axis (p < 0.01). Patellar tilt was significantly decreased at 90° and 120° by closure 3 cm distal (p < 0.01) and at 120° when closed 1.5 cm distal (p < 0.05).

Conclusions

Imprecise arthrotomy closure significantly impacted patellar kinematics and passive range of motion. Therefore, every effort should be made to provide anatomical closure of the extensor mechanism to preserve native patellar movement kinematics.

Level of evidence

V.

Keywords

KneeApproachMovement kinematicsTrackingNavigation

Copyright information

© Springer-Verlag Berlin Heidelberg 2013