Woodward RM, Vesey RM, Bacon CJ, White SG, Brick MJ, Blankenbaker DG. Microinstability of the hip: a systematic review of the imaging findings.
Skeletal Radiol 2020;
49:1903-1919. [PMID:
32583134 DOI:
10.1007/s00256-020-03516-7]
[Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 05/31/2020] [Accepted: 06/10/2020] [Indexed: 02/02/2023]
Abstract
OBJECTIVES
To undertake a systematic review of the morphologic features associated with hip microinstability and determine whether there are suggestive or diagnostic imaging findings.
METHODS
Four electronic databases were searched up to September 2019 to identify original research reporting morphologic features in individuals with either a clinical diagnosis of hip microinstability (instability without overt subluxation/dislocation) or those with symptomatic laxity demonstrated on imaging (increased femoral head translation/distraction or capsular volume). Studies focussing on individuals with pre-existing hip conditions (including definite dysplasia (lateral centre edge angle < 20°), significant trauma, previous dislocation or surgery were excluded. Methodological quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies 2 tool.
RESULTS
Twenty-two studies met inclusion criteria (clinical diagnosis of microinstability n = 15 and demonstration of laxity n = 7). Imaging information gathered from the studies includes radiographs (n = 14), MRI (n = 6), MR arthrography (n = 4), CT (n = 1) and intraoperative examination. Most studies exhibited design features associated with an overall high or unclear risk of bias. Some dysplastic features are associated with microinstability or laxity reference measures; however, microinstability is frequently diagnosed in those with a lateral centre edge angle > 25°. Other associated imaging findings reported include impingement morphology, anterior labral tearing, femoral head chondral injury, ligamentum teres tears and capsular attenuation.
CONCLUSIONS
The current literature does not provide strong evidence for imaging features diagnostic of microinstability. In the appropriate clinical context, dysplastic morphology, anterior labral tears and ligamentum teres tears may be suggestive of this condition although further research is needed to confirm this.
PROSPERO REGISTRATION
CRD42019122406.
Collapse