Nicola Maffulli MD MS PhD FRCS (Orth)1,2, Domiziano Tarantino MD1, and Rocco Aicale MD1 1 Department of Musculoskeletal Disorders, School of Medicine and Surgery, University of Salerno, Salerno, Italy 2 Queen Mary University of London, Barts and the London School of Medicine and Dentistry, Centre for Sports and Exercise Medicine, Mile End Hospital, London, UK Table 134.1 Correlation between MRI, arthroscopy, and ultrasonography. SD: standard deviation; PPV: positive predictive value; NPV: negative predictive value; M: medial; L: lateral; M+L medial and lateral. MRI is the gold standard for the diagnosis of meniscal tears. USs are a suitable noninvasive and safe alternative tool to establish a diagnosis of meniscal tear. Current opinion suggests that MRI is preferable to diagnostic arthroscopy in most patients because it avoids the surgical risks of arthroscopy with high accuracy in diagnosing meniscal and anterior cruciate ligament (ACL) tears.1 US has been proposed in case of contraindications for MRI, such as the presence of indwelling cardiac pacemakers, metal implants, patient intolerance due to claustrophobia, and delay in treatment due to long wait periods.2 A number of different studies have evaluated the role of US for meniscal tear diagnosis, both alone or in comparison with MRI and/or arthroscopy. Three systematic review and meta‐analyses evaluated the diagnostic accuracy of US for meniscal tears.3–5 One trial (n = 70 patients) provided the correlation between arthroscopy and US,6 stating that US may be used for screening for meniscal tears (Table 134.1). Three trials (n = 71, n = 15, and n = 50 patients, respectively) determined the clinical usefulness of US for diagnosis of meniscal injuries and compared its diagnostic accuracy to MRI (Table 134.1).7–9 Two trials (n = 74 and n = 35 patients, respectively) provided the correlation between MRI, US, and arthroscopy for meniscal tears diagnosis (Table 134.1).10,11 Dai et al. and Xia et al. found that US has high specificity (0.90; 95% confidence interval [CI]: 0.86–0.93 and 0.838; 95% CI: 0.818–0.857, respectively) and moderate sensitivity (0.88; 95% CI: 0.84–0.91 and 0.775; 95% CI: 0.747–0.801, respectively),3,4 while Dong et al. found that two‐dimensional US has higher sensitivity (0.888; 95% CI: 82.83–92.87) than specificity (0.846; 95% CI: 75.89–90.64).5 All three studies agreed that the diagnostic accuracy of US for meniscal injury was acceptable, and that US could be routinely used to diagnose meniscal tears. Cook et al. stated that US is a useful tool for diagnosis of meniscal pathology with potential advantages over MRI.7 Mahdy et al. and Mostafa et al. pointed out that US (especially high resolution US) examination may be suitable for screening for meniscal tears, but detection of the morphology of meniscal tears seems insufficient, with MRI being more sensitive in detection and determination of tear type.8,9 Alizadeh et al. stated that US could be effective as an initial investigation for tears of medial meniscus for patients aged 30 or less,10 while Unlu et al. concluded out that US is not a suitable alternative for MRI in the routine diagnostic evaluation of meniscal tears, and that only in selected cases, such as young patients, traumatic cases, and cases with a contraindication for MRI, US may find a role as a quick exam to stratify patients for further evaluation.11 Overall, there is consensus about the usefulness of US for meniscal tears detection. Level I evidence suggests that US could be used as a reliable tool, with a good diagnostic accuracy.3–10 However, level I evidence also suggests that US cannot completely replace MRI for meniscal tear diagnosis, particularly for classifying tear type.11
134 Meniscal Tears
Clinical scenario
Reference
Level of evidence
Total no. of patients studied
Age of patients mean (SD)
Affected meniscus
Sensitivity
Specificity
PPV
NPV
Diagnostic accuracy
Akatsu et al.6
II
70
33.5 (‐)
M
0.95 (0.87–0.100)
0.82 (0.69–0.94)
0.85
0.93
—
L
0.79 (0.66–0.93)
0.89 (0.77–0.100)
0.85
0.84
—
M+L
0.88 (0.80–0.96)
0.85 (0.77–0.94)
0.85
0.88
—
Cook et al.7
II
71
37.2 (‐)
M+L
0.91
0.84
0.95
0.76
0.9
Mahdy et al.8
II
15
30.4 (‐)
M+L (overall)
0.88 (overall)
—
—
—
—
Mostafa et al.9
II
50
37.65 (10.24)
M+L
0.89
0.77
—
—
0.81
Alizadeh et al.10
II
74
33.5 (7.15)
M+L
0.83 (0.65–0.94)
0.71 (0.29–0.96)
0.92 (0.76–0.99)
0.50 (0.19–0.81)
0.81 (0.65–0.92)
Unlu et al.11
II
35
—
M+L
0.91
0.64
—
—
—
Top three questions
Question 1: In patients with suspected meniscal lesions, is US preferable for tear detection compared to arthroscopy and MRI?
Rationale
Clinical comment
Available literature and quality of the evidence
Findings
Resolution of clinical scenario