Validation of Panoramic Ultrasound Measurement of the Cross-Sectional Area of the Vastus Medialis.

ABSTRACT: Minnehan, KS, Dexter, WW, Holt, CT, Scharnetzki, L, Alex, JP, Chin, KE, and Kokmeyer, DJ. Validation of panoramic ultrasound measurement of the cross-sectional area of the vastus medialis. J Strength Cond Res 37(1): 41-45, 2023-The cross-sectional area (CSA) of the vastus medialis (VM) is an independent predictor of important clinical outcomes in musculoskeletal conditions of the knee, such as pain and long-term function. Previous studies validated ultrasound (US) to measure larger muscles of the thigh, but this approach has limited accuracy in measuring smaller muscles, such as the VM. In this study, we aimed to validate panoramic US measurements of the CSA of the VM and compare the results with those from the gold standard of magnetic resonance imaging (MRI) (significance set p ≤ 0.05). In this retrospective, single-center study, we compared pairs of US and MRIs taken of 25 adults who participated in a 10-week study of non-weight-bearing activity at a National Aeronautics and Space Administration facility. Images were acquired from various locations on the right thigh at multiple time points. Two researchers independently analyzed the US and MRI pairs by outlining the intermuscular border of the VM in the most distal image. We found excellent agreement between the US and MRI measurements of the CSA of the VM analyzed by researcher 1 (interclass correlation coefficient [ICC]: 0.997) and researcher 2 (ICC: 0.980). We also found excellent agreement for interrater reliability for MRI (ICC: 0.988) and US (ICC: 0.982) and intrarater reliability for US for researcher 1 (ICC: 0.999) and researcher 2 (ICC: 0.996). Our findings demonstrate that US is a valid and reliable tool for measuring the CSA of the VM compared with MRI.

The reliability of multitest regimens with sacroiliac pain provocation tests.

BACKGROUND: Studies concerning the reliability of individual sacroiliac tests have inconsistent results. It has been suggested that the use of a test regimen is a more reliable form of diagnosis than individually performed tests. OBJECTIVE: To assess the interrater reliability of multitest scores by using a regimen of 5 commonly used sacroiliac pain provocation tests. METHODS: Two examiners examined 78 subjects. The threshold for a positive selection was set at 3 positive tests out of 5 tests performed. The test order and the order in which the subjects were examined were randomized per patient, and the examiners were blinded from all information regarding the subjects tested. Fifty-nine of the subjects were symptomatic for low back pain, and 19 of the subjects were asymptomatic. Weighted kappa statistic, bias-adjusted kappa, prevalence-adjusted kappa, and 95% CI intervals were used to evaluate the interrater reliability of the test regimen. RESULTS: Weighted kappa was found to be 0.70 (95% CI = 0.45-0.95). CONCLUSIONS: A multitest regimen of 5 sacroiliac joint pain provocation tests is a reliable method to evaluate sacroiliac joint dysfunction, although further study is needed to assess the validity of this test method.