Knee Surgery, Sports Traumatology, Arthroscopy

, Volume 15, Issue 8, pp 1009–1012 | Cite as

Development of a simple device for measurement of rotational knee laxity

  • Volker MusahlEmail author
  • Kevin M. Bell
  • Andrew G. Tsai
  • Ryan S. Costic
  • Robert Allaire
  • Thore Zantop
  • James J. Irrgang
  • Freddie H. Fu


The goal of this study was to develop a new device for the measurement of rotational knee laxity and to measure intra-observer and inter-observer reliability in a cadaveric study. An array of established tools was utilized to design the device with a basis that consists of an Aircast Foam Walker™ boot. A load cell was attached to the boot with a handle bar for application of moments about the knee. An electromagnetic tracking system was used to record the motion of the tibia with respect to the femur. The total arc of motion ranged from 23° at full extension to 46° at 90° of knee flexion. The intra-tester ICCs ranged from 0.94 to 0.99. The ICC for inter-tester reliability ranged from 0.95 to 0.99. In summary, the new device for measurement of rotational knee laxity is simple, reliable, and can be used in a non-invasive fashion in the office or surgical suite document clinical outcome in terms of rotational knee laxity.


ACL Rotation Laxity Device Electromagnetic tracking Knee 



The authors gratefully acknowledge the support of the Ferguson Laboratory, the Albert B. Ferguson Jr., M.D. Orthopedic Foundation, and Aircast Inc. for funding of this project. The authors would also like to acknowledge the mentorship by Dr. Lars G Gilbertson in the early stages of the project.


  1. 1.
    Daniel DM et al (1985) Instrumented measurement of anterior laxity of the knee. J Bone Joint Surg Am 67(5):720–726PubMedGoogle Scholar
  2. 2.
    Uh BS et al (2001) A new device to measure knee laxity during weightbearing and non-weightbearing conditions. J Orthop Res 19(6):1185–1191PubMedCrossRefGoogle Scholar
  3. 3.
    Highgenboten CL, Jackson A, Meske NB (1989) Genucom, KT-1000, and Stryker knee laxity measuring device comparisons. Device reproducibility and interdevice comparison in asymptomatic subjects. Am J Sports Med 17(6):743–746PubMedCrossRefGoogle Scholar
  4. 4.
    Almquist PO et al (2002) Evaluation of an external device measuring knee joint rotation: an in vivo study with simultaneous Roentgen stereometric analysis. J Orthop Res 20(3):427–432PubMedCrossRefGoogle Scholar
  5. 5.
    Christel P (2005) Anterior cruciate ligament and rotation stability. Rev Chir Orthop Reparatrice Appar Mot 91(S8):18–22PubMedGoogle Scholar
  6. 6.
    Koh J (2005) Computer-assisted navigation and anterior cruciate ligament reconstruction: accuracy and outcomes. Orthopedics 28(Suppl 10):s1283–s1287PubMedGoogle Scholar
  7. 7.
    Zaffagnini S et al (2006) New intraoperative protocol for kinematic evaluation of ACL reconstruction: preliminary results. Knee Surg Sports Traumatol Arthrosc 14(9):811–816PubMedCrossRefGoogle Scholar
  8. 8.
    Martelli S et al (2006) Validation of a new protocol for computer-assisted evaluation of kinematics of double-bundle ACL reconstruction. Clin Biomech (Bristol, Avon) 21(3):279–287CrossRefGoogle Scholar
  9. 9.
    Musahl V, Plakseychuk A, Fu FH (2002) Current opinion on computer-aided surgical navigation and robotics: role in the treatment of sports-related injuries. Sports Med 32(13):809–818PubMedCrossRefGoogle Scholar
  10. 10.
    Moore SM et al (2004) Multidirectional kinematics of the glenohumeral joint during simulated simple translation tests: impact on clinical diagnoses. J Orthop Res 22(4):889–894PubMedCrossRefGoogle Scholar
  11. 11.
    Bull AM et al (2002) Intraoperative measurement of knee kinematics in reconstruction of the anterior cruciate ligament. J Bone Joint Surg Br 84(7):1075–1081PubMedCrossRefGoogle Scholar
  12. 12.
    Kurosaka M (2006) Comparison of double bundle anatomic, single antero-medial, and single postero-lateral ACL reconstructions. Short term prospective-randomized follow-up study. In ACL study group. Hawaii, USAGoogle Scholar
  13. 13.
    Benoit DL et al (2006) Effect of skin movement artifact on knee kinematics during gait and cutting motions measured in vivo. Gait Posture 24(2):152–164PubMedCrossRefGoogle Scholar
  14. 14.
    Leardini A et al (2005) Human movement analysis using stereophotogrammetry. Part 3. Soft tissue artifact assessment and compensation. Gait Posture 21(2):212–225PubMedCrossRefGoogle Scholar
  15. 15.
    Fujie H et al (1993) The use of robotics technology to study human joint kinematics: a new methodology. J Biomech Eng 115(3):211–217PubMedGoogle Scholar
  16. 16.
    Rudy TW et al (1996) A combined robotic/universal force sensor approach to determine in situ forces of knee ligaments. J Biomech 29(10):1357–1360PubMedCrossRefGoogle Scholar
  17. 17.
    Reuben JD et al (1989) Three-dimensional dynamic motion analysis of the anterior cruciate ligament deficient knee joint. Am J Sports Med 17(4):463–471PubMedCrossRefGoogle Scholar
  18. 18.
    Slocum DB et al (1976) Clinical test for anterolateral rotary instability of the knee. Clin Orthop Relat Res 118:63–69PubMedGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Volker Musahl
    • 1
    Email author
  • Kevin M. Bell
    • 1
  • Andrew G. Tsai
    • 1
  • Ryan S. Costic
    • 1
  • Robert Allaire
    • 1
  • Thore Zantop
    • 1
  • James J. Irrgang
    • 1
  • Freddie H. Fu
    • 1
  1. 1.Department of Orthopaedic SurgeryUniversity of PittsburghPittsburghUSA

Personalised recommendations