title: Pelvic and lower extremity physiological cross-sectional areas: an MRI study of the living young and comparison to published research literature.
abstract: OBJECTIVE
  Morphological data pertaining to the pelvis and lower extremity muscles are increasingly being used in biomechanical modeling to compare healthy and pathological conditions. Very few data sets exist that encompass all of the muscles of the lower limb, allowing for comparisons between regions. The aims of this study were to (a) provide physiological cross-sectional area (PCSA) data for the pelvic, thigh, and leg muscles in young, healthy participants, using magnetic resonance imaging (MRI), and (b) to compare these data with summarized PCSAs obtained from the literature.
  
  
  METHODS
  Six young and healthy volunteers participated and were scanned using 3 T MRI. PCSAs were calculated from volumetric segmentations obtained bilaterally of 28 muscles/muscle groups of the pelvis, thigh, and leg. These data were compared to published, summarized PCSA data derived from cadaveric, computed tomography, MRI and ultrasound studies.
  
  
  RESULTS
  The PCSA of the pelvis, thigh, and leg muscles tended to be 20-130% larger in males than in females, except for the gemelli which were 34% smaller in males, and semitendinosus and triceps surae which did not differ (<20% different). The dominant and the non-dominant sides showed similar and minutely different PCSA with less than 18% difference between sides. Comparison to other studies revealed wide ranges within, and large differences between, the cadaveric and imaging PCSA data. Comparison of the PCSA of this study and published literature revealed major differences in the iliopsoas, gluteus minimus, tensor fasciae latae, gemelli, obturator internus, biceps femoris, quadriceps femoris, and the deep leg flexor muscles.
  
  
  CONCLUSIONS
  These volume-derived PCSAs of the pelvic and lower limb muscles alongside the data synthesised from the literature may serve as a basis for comparative and biomechanical studies of the living and healthy young, and enable calculation of muscle forces. Comparison of the literature revealed large variations in PCSA from each of the different investigative modalities, hampering comparability between studies. Sample size, age, post-mortem changes of muscle tone, chemical fixation of cadaveric tissues, and the underlying physics of the imaging techniques may potentially influence PCSA calculations.
authors.affiliation: Department of Anatomy, Faculty of Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Lube
authors.affiliation: Department of Anatomy, University of Otago, 270 Great King St., Dunedin, 9016, New Zealand.
authors.forename: Natasha A M S
authors.initials: NAMS
authors.lastname: Flack
authors.affiliation: Department of Anatomy, Ross University School of Medicine, Roseau, Dominica.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Cotofana
authors.affiliation: Department of Orthopedic, Trauma and Plastic Surgery, University of Leipzig, Leipzig, Germany.
authors.forename: Orkun
authors.initials: O
authors.lastname: Özkurtul
authors.affiliation: Department of Anatomy, University of Otago, 270 Great King St., Dunedin, 9016, New Zealand.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Woodley
authors.affiliation: Visualization and Data Analysis, Zuse Institute Berlin, Berlin, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Zachow
authors.affiliation: Department of Anatomy, Faculty of Medicine, University of Leipzig, Leipzig, Germany. nlshammer@googlemail.com.|Department of Anatomy, University of Otago, 270 Great King St., Dunedin, 9016, New Zealand. nlshammer@googlemail.com.
authors.forename: Niels
authors.initials: N
authors.lastname: Hammer
mesh_terms: D064368:Healthy Volunteers; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D010388:Pelvis / Q000033:anatomy & histology*; D012737:Sex Factors; D013848:Thigh / Q000033:anatomy & histology*
keywords: 3 Telsa magnetic resonance imaging; Leg; Living young; Lower extremity; PCSA; Pelvis; Segmentation; Thigh; Volume