title: Predictability of sacral base levelness based on iliac crest measurements.
abstract: A level sacral base plane is necessary to allow normalization of complex lumbosacral mechanics. Palpatory examinations are often used to evaluate for leg length discrepancy and pelvic obliquity despite improved accuracy and consistency of radiographic techniques. Treatment based on palpatory examinations suppose a direct and consistent relationship between the pelvic bones (innominates) and the sacral base. To evaluate the relationship between iliac crest levelness and sacral base levelness, a radiographic postural survey in the upright, weight-bearing position was performed on 358 men and women thought to have pelvic obliquity. Of these subjects, 293 demonstrated unlevel iliac crest heights or sacral base > or = 3/16 inch (4.76 mm), with iliac crest heights accurately predicting sacral base position 62% of the time. At > or = 3/8 inch (9.53 mm), 68% of the cases were accurately predicted. When the criterion for unlevelness was increased to > or = 1/2 inch (12.70 mm), the predictive accuracy improved to 83%. Radiographic findings in this study demonstrate a significant difference between iliac crest heights and sacral base position. In cases of mild to moderate short leg syndromes, the iliac crest height is an unreliable predictor of the direction or degree of sacral base levelness.
authors.affiliation: Department of Manipulative Medicine, University of North Texas Health Science Center at Fort Worth/Texas College of Osteopathic Medicine 76107.
authors.forename: G A
authors.initials: GA
authors.lastname: Dott
authors.forename: C L
authors.initials: CL
authors.lastname: Hart
authors.forename: C
authors.initials: C
authors.lastname: McKay
mesh_terms: D000328:Adult; D000886:Anthropometry; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007085:Ilium / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D007870:Leg Length Inequality / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010808:Physical Examination; D011187:Posture; D011237:Predictive Value of Tests; D011859:Radiography; D015203:Reproducibility of Results; D012447:Sacrum / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D016474:Weight-Bearing