Quality assessment of radiological measurements of trochlear dysplasia; a literature review.
OBJECTIVE
To make a systematic review with quality assessments of the known measurements used to describe trochlear dysplasia.


METHODS
A systematic literature search was conducted in the databases PubMed and Embase using the search string "trochlea dysplasia OR trochlear dysplasia". Papers were screened for their relevance based on predefined parameters, and all measurements showing a statistical association between trochlear dysplasia and patellar instability were presented. Four experts evaluated the quality of the measures using a purpose-made quality scale.


RESULTS
The search generated 600 papers of which eight were chosen for review. Thirty-three unique measurements were identified and described in order of their date of publication. The lateral trochlea inclination was rated highest by the expert panel. The crossing sign, the trochlea bump, the TT-TG distance, the trochlea depth and the ventral trochlea prominence also had high ratings.


CONCLUSIONS
Thirty-three unique measurements were identified with the lateral trochlea inclination as the highest rated measurement by the expert panel, and it is recommended for use in assessment of trochlear dysplasia. The crossing sign, the trochlea bump, the TT-TG, the trochlea depth and the ventral trochlea prominence were also rated well and can be recommended for use.


METHODS
V.
Sports Orthopedic Research Center Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark. Mathiasdepaiva@hotmail.com.
Mathias
http://orcid.org/0000-0002-6453-8673
M
Paiva
Zealand University Hospital, Køge and Aleris-Hamlet Parken, Copenhagen, Denmark.
Lars
L
Blønd
Sports Orthopedic Research Center Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark.
Per
P
Hölmich
Orthopedic Surgery Residency, Mount Carmel Health System, Columbus, OH, USA.
Robert N
RN
Steensen
Department of Radiology, Charite - Universitaetsmedizin Berlin, Campus Charite Mitte, Berlin, Germany.
Gerd
G
Diederichs
OrthoSport Victoria Research Unit, Epworth Healthcare and Deakin University, Melbourne, Australia.
Julian A
JA
Feller
Sports Orthopedic Research Center Copenhagen (SORC-C), Department of Orthopedic Surgery, Copenhagen University Hospital, Amager-Hvidovre, Denmark.
Kristoffer Weisskirchner
KW
Barfod
D001848:Bone Diseases, Developmental / Q000150:complications / Q000175:diagnosis*; D005269:Femur / Q000000981:diagnostic imaging*; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000209:etiology; D007719:Knee Joint / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000592:standards*
Anterior knee pain; Patellar instability; Patellofemoral; Patellofemoral pain; Trochlear dysplasia