Dynamic knee laxity measurement devices.
OBJECTIVE
Studies have reported that knee kinematics and rotational laxity are not restored to native levels following traditional anterior cruciate ligament (ACL) reconstruction. This has led to the development of anatomic ACL reconstruction, which aims to restore native knee kinematics and long-term knee health by replicating normal anatomy as much as possible. The purpose of this review is to give an overview of current dynamic knee laxity measurement devices with the purpose of investigating the significance of dynamic laxity measurement of the knee. Gait analysis is not included.


METHODS
The subject was discussed with experts in the field in order to perform a level V review. MEDLINE was searched according to the discussions for relevant articles using multiple different search terms. All found abstracts were read and scanned for relevance to the subject. The reference lists of the relevant articles were searched for additional articles related to the subject.


RESULTS
There are a variety of techniques reported to measure dynamic laxity of the knee. Technical development of methods is one important part toward better understanding of knee kinematics. Validation of devices has shown to be difficult due to the lack of gold standard. Different studies use various methods to examine different components of dynamic laxity, which makes comparisons between studies challenging.


CONCLUSIONS
Several devices can be used to evaluate dynamic laxity of the knee. At the present time, the devices are continuously under development. Future implementation should include primary basic research, including validation and reliability testing, as well as part of individualized surgery and clinical follow-up.


METHODS
Diagnostic study, Level V.
Department of Orthopaedics, Sahlgrenska University Hospital/Mölndal, 431 80 Mölndal, Sweden. mattias.e.ahlden@vgregion.se
Mattias
M
Ahldén
Yuichi
Y
Hoshino
Kristian
K
Samuelsson
Paulo
P
Araujo
Volker
V
Musahl
Jón
J
Karlsson
D000054:Acceleration; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D053587:Arthrometry, Articular / Q000295:instrumentation*; D001696:Biomechanical Phenomena; D055590:Electromagnetic Phenomena; D004867:Equipment Design; D004869:Equipment Safety; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000601:surgery; D007718:Knee Injuries / Q000175:diagnosis / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010808:Physical Examination / Q000295:instrumentation; D015641:Radiography, Interventional; D016059:Range of Motion, Articular / Q000502:physiology; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods