Maximum Muscle Thickness Research Articles

Neuromuscular maturation in the neonate: Combined electroneurographic and ultrasonographic study

BackgroundThe combined electroneurography and muscle ultrasound examination (ENG-USM) in adult patients showed a correlation between the compound motor action potential (CMAP) and muscular thicknesses (MT). No similar studies exist regarding the neonatal period. AimTo evaluate the correlations between the maximum compound muscle action potential (CMAP) and maximum muscle thickness (MT) in term and premature newborns versus a group of young adults, as measured by combined electroneurography-ultrasonography (ENG-USM) to assess the stages. Study designObservational cohort study. SubjectsWe studied 36 subjects (14 premature and 11 term infants, and 11 young adults), who underwent ENG-USM of the tibialis anterioris (TA) muscle. Outcome measuresWe measured: 1) Onset-Peak (O-P) and Peak-to-Peak (P-P) maximum CMAP; 2) maximum MT; and 3) MT at the detected maximum CMAP. ResultsThe maximum CMAP in term newborns studied was about 1/3 of the mean value measured in the adults; the differences between O-P and P-P values of the term versus premature infants were not significant. We did not find a good correlation between maximum MT and maximum CMAP in the term (r = 0.63) newborns, contrary to what was found in preterms (r = 0.95) and in young adults (r = 0.98). ConclusionOur ENG-USM study shows that in newborns, the site of innervation of the neuromuscular plaque does not correspond to MT since muscle growth is related to the period of development, and depends on the progression of the nerve terminal branches that go to innervate the same muscle.

Early postpartum pelvic floor changes in primiparous women after vaginal delivery using 3T MRI

AIMSDetection of early morphological pelvic floor changes after vaginal delivery in primiparous women using 3 Tesla magnetic resonance imaging.METHODSA 3 Tesla magnetic resonance imaging was performed using static T2‐weighted turbo spin echo (tse) in three planes, T2‐weighted tse fat saturated and T1‐weighted sequence in transverse plane. All visible changes of pelvic structures (edema, hematoma, tear, or avulsion) were documented. Measurements for the integrity of the pelvic floor were performed and compared to a nulliparous control‐group. Differences in pelvic floor parameters were analyzed using an unpaired t‐test. P<0.05 was considered statistically significant.RESULTSTwenty‐five primiparous women delivered vaginally at term and underwent postpartum magnetic resonance imaging. Several morphological changes in the pelvis, superficial as well as deep, were detected in all participants. Anteroposterior hiatus, hiatal circumference, hiatal area, laterolateral hiatus, maximum muscle thickness, and levator urethra gap were significantly different to the nulliparous control‐group.CONCLUSIONSTwo‐dimensional 3 Tesla magnetic resonance imaging is feasible in a clinical and early postpartum setting establishing a reliable diagnostic tool to evaluate numerous morphological pelvic floor changes and the integrity of the pelvic floor.

3 T MRI-based measurements for the integrity of the female pelvic floor in 25 healthy nulliparous women.

Measurements indicating a loss of integrity of the levator ani muscle, which is an integral part of the pelvic floor, have been subject of recent studies using translabial ultrasound and 3D-MRI-models. We transferred these measurements into 2D-3 T-MR-images for clinical routine, as it is objective and does not need exhaustive post-processing. The trial was accepted by the local ethics committee. 25 healthy volunteers fulfilled the inclusion criteria and gave written informed consent. Using high-resolution T2-weighted images (TE 5030-7810 ms, TR 88-112 ms, matrix 512, FOV 280-300 mm, ST 2-3 mm), measurements of anteroposterior hiatus (APH), laterolateral hiatus (LLH), hiatal area (HA), hiatal circumference (HC), levator area (LA), maximum muscle thickness (MMT) and levator urethra gap (LUG) were transferred from ultrasound, iliococcygeus width (IW), puborectalis attachment width (PAW), and levator symphysis gap (LSG) were transferred from 3D-MRI-models. We compared our results to previous studies in the literature. Mean value was 52.22 ± 6.97 mm for APH, 33.15 ± 4 mm for LLH, 13.22 ± 3.05 cm(2) for HA, 14.19 ± 1.61 cm for HC, 7.14 ± 1.85 cm(2) for LA, 6.45 ± 2.07 mm for MMT, 19.47 ± 2.38 mm for LUG, 45 ± 3.97 mm for IW, 33.94 ± 3.34 mm for PAW, 20.54 ± 5.29 mm for LSG. Our results for APH, HA, LUG, and with limitations LA, were comparable to the literature, while HC, LLH, and MMT showed anatomical variances. Results for IW and LSG were comparable, but challenging to measure. We newly proposed a cutoff value for PAW. 2D-3 T-MRI combines high-resolution images with objective measurements of parameters regarding pelvic floor integrity, without resorting to exhaustive post-processing methods. Our results may provide a good foundation for further 2D-MR-studies.

A Comparison of 2 Techniques for Measuring Rectus Femoris Muscle Thickness in Cerebral Palsy

: Precise measures of muscle size are useful when investigating weakness in children with cerebral palsy (CP). Therefore, the purpose of the study was to determine agreement between 2 muscle thickness measurements of the rectus femoris (RF) in CP. : Measures of RF thickness in 13 youth with CP who were ambulatory (mean age: 14.4 ± 3.6 years) were obtained bilaterally using ultrasound imaging. Three measures were obtained at 50% thigh length and averaged (MT50). Maximum muscle thickness (MaxMT) was also determined through repeated measurements toward the proximal insertion of the RF. : The Bland-Altman plot showed that all values, except for one outlier, fell within 95% limits of agreement (-0.11 to 0.28 cm), showing excellent agreement. However, a constant bias toward higher values with MaxMT method was observed. : Given the time-consuming nature of obtaining MaxMT, the MT50 measurement may be a more feasible alternative when estimating maximum muscle thickness of the RF.