Magnetic resonance imaging of posterolateral plica of the elbow joint: Asymptomatic vs. symptomatic subjects

Abstract

BackgroundMagnetic resonance imaging (MRI) may be useful to diagnose a posterolateral plica syndrome of the elbow joint because this syndrome has less clear clinical features. The purposes of this study were to document mediolateral and sagittal dimensions of a posterolateral synovial fold and to determine the proportion of subjects with the posterolateral plica in asymptomatic elbows. We also aimed to determine whether the dimensions of the posterolateral synovial fold and the prevalence of the plica differ between symptomatic and asymptomatic subjects.Materials and methodsThis retrospective review of prospectively collected data included 50 asymptomatic elbows (asymptomatic group) and 14 elbows with arthroscopically confirmed posterolateral plicae (plica group). The mediolateral and sagittal dimensions of the posterolateral synovial fold were measured. In addition, the criteria for the prevalence of posterolateral plica was determined with conventional MRI as synovial fold dimension ≥ 3 mm and coverage of radial head by synovial fold ≥ 30%.ResultsThe plica group showed larger posterolateral synovial fold dimensions compared to the asymptomatic group. The median mediolateral and sagittal dimensions of the synovial fold in the asymptomatic group were 3.8 mm and 4.7 mm, respectively. Dimensions in the plica group were 7.0 mm and 7.4 mm, respectively. When the presence of posterolateral plica was determined using the dimension criteria, there was no difference in the prevalence of the plica between the asymptomatic and the plica group. However, using the coverage criteria, the prevalence of posterolateral elbow plica was significantly greater in the plica group than the asymptomatic group (64% vs. 18%; p < 0.001).ConclusionsThe patients who underwent arthroscopic surgery for posterolateral plica syndrome had larger dimensions of the posterolateral synovial fold and higher prevalence of the posterolateral plica on conventional MRI compared to the asymptomatic subjects.

Plicae: Where Do They Come from and When Are They Relevant?

“…Choi et al found that symptomatic patients are more likely to have larger plicae on MRI, covering 30% of the radial head on either mediolateral or sagittal (or anteroposterior) dimension. 71 However, an earlier work by Ruiz de Luzuriaga et al did not reproduce the result to a statistical significance. 72 A cutoff thickness of 2.6 mm on MRI was also suggested to help identify patients with plica syndrome but was not shown to be statistically significant.…”

“…61 It can be visualized in 92 to 98% of elbows in healthy volunteers. 61,71 Sagittal and coronal planes are most useful to visualize the posterolateral plica using T2-weighted imaging (or other fluid-sensitive sequences such as proton-density fat-suppressed (PD FS) or spectral attenuated inversion recovery [SPAIR]). 61,71,72 However, the rate of MRI visualization of the radiohumeral plica is not consistently high across the literature, with Vahlensieck et al detecting only 24% in their 42 elbow cadaveric specimens.…”

“…15 and 16). 71 Decision to intervene surgically should ultimately be based on persistent symptoms and failure to respond to conservative management.…”

A Comprehensive Review of Radiohumeral Synovial Plicae for a Correct Clinical Interpretation in Intractable Lateral Epicondylitis

“…On the other hand, several studies demonstrate that RHSPS can often be associated with alterations of the radial head [1,2,4,6,14,17] and capitellum [1,2,6,7]. It is postulated that the mechanical abrasion by a snapping plica may produce chondromalacia along the radial head and capitellum [22], but it has not been clearly demonstrated whether there is a direct significant correlation between both of them.…”

“…RHSPS may be confused with lateral epicondylitis [2, 3•, 4-6, 9, 13, 24], but it must also be included in the differential diagnosis of other clinical entities that present with anterolateral and/or posterolateral elbow pain [1, 4-8, 10, 12, 24], snapping [1, 2, 3•, 5, 9-11, 13], catching [1, 3•, 4, 13], mobility restriction [3•, 4, 6, 13, 18, 29], pitching [29], clicking [4][5][6], locking/blockage [4,11], popping [11,13] and/or swelling [6]. RHSPS can be an isolated condition or it can be associated with other elbow abnormalities [9,17,31].…”