BackgroundSeveral types of Magnetic resonance imaging (MRI) are commonly used in imaging of femoroacetabular impingement (FAI), however till now there are no clear protocols and recommendations for each type. The aim of this meta-analysis is to detect the accuracy of conventional magnetic resonance imaging (cMRI), direct magnetic resonance arthrography (dMRA) and indirect magnetic resonance arthrography (iMRA) in the diagnosis of chondral and labral lesions in femoroacetabular impingement (FAI).MethodsA literature search was finalized on the 17th of May 2016 to collect all studies identifying the accuracy of cMRI, dMRA and iMRA in diagnosing chondral and labral lesions associated with FAI using surgical results (arthroscopic or open) as a reference test. Pooled sensitivity and specificity with 95% confidence intervals using a random-effects meta-analysis for MRI, dMRA and iMRA were calculated also area under receiver operating characteristic (ROC) curve (AUC) was retrieved whenever possible where AUC is equivocal to diagnostic accuracy.ResultsThe search yielded 192 publications which were reviewed according inclusion and exclusion criteria then 21 studies fulfilled the eligibility criteria for the qualitative analysis with a total number of 828 cases, lastly 12 studies were included in the quantitative meta-analysis.Meta-analysis showed that as regard labral lesions the pooled sensitivity, specificity and AUC for cMRI were 0.864, 0.833 and 0.88 and for dMRA were 0.91, 0.58 and 0.92. While in chondral lesions the pooled sensitivity, specificity and AUC for cMRI were 0.76, 0.72 and 0.75 and for dMRA were 0.75, 0.79 and 0.83, while for iMRA were sensitivity of 0.722 and specificity of 0.917.ConclusionsThe present meta-analysis showed that the diagnostic test accuracy was superior for dMRA when compared with cMRI for detection of labral and chondral lesions.The diagnostic test accuracy was superior for labral lesions when compared with chondral lesions in both cMRI and dMRA. Promising results are obtained concerning iMRA but further studies still needed to fully assess its diagnostic accuracy.Electronic supplementary materialThe online version of this article (doi:10.1186/s12891-017-1443-2) contains supplementary material, which is available to authorized users.

Twenty rabbits were divided into two matching groups. Holes of 1 cm2 area were bored through the full thickness of the pinna of both ears in each rabbit. In group I, the right ears were irradiated with pulsed ultrasound three times/week for 18 weeks. In group II, the right ears were irradiated with ultraviolet rays using a hot quartz lamp, three times/week for 18 weeks. The left ears in all rabbits were not irradiated and acted as controls. The rate of wound healing was calculated in terms of decrease in surface area of the wounds measured with a planimeter from enlarged photographs taken from the wound edges at the end of third, fifth and seventh weeks. The results revealed that ultrasound has a better effect on promotion of tissue regeneration than ultraviolet irradiation, as evidenced by both reduction in the surface area of wounds and by histopathological examination.