Table 2

Summary of findings

Study Type of LLI Subjects Methodology Results Comments

1. Pitkin and Pheasant17 Artificial 144 Female college students Pelvic inclinometer using plumb line/1.5 in (38.1 mm) wood block to create LLI Posterior innominate rotation on side of lifted leg and anterior rotation on nonlifted side; range, 3-19°; mean, 11°. Baseline: right PI 1.3°. Pelvic torsion did not entirely correct induced pelvic tilt. Pioneering study. Descriptive statistics only. Only 1 lift size used, preventing determination of dose relationship. Very large (1.5 in) LLI created, beyond expected clinical amounts that might occur. No left vs right outcomes reported. Induced torsional spread inconsistent with anatomical studies for joint ROM. No information on reliability and validity of inclinometer used.

2. Drerup B, Hierholzer20 Artificial 20 Scoliosis patients (sex not provided) Rasterstereographic measurement of dimples of Venus/up to 30 mm of block inserted (applied in 5-mm increments) to create LLI A 20% “dimple lag” on lifted side suggested posterior innominate rotation on lifted side, anterior rotation on nonlifted side. Calculated up to 6.4° of torsional spread compared with baseline. Dose relationship reported; very linear. Not known if scoliosis patients in study exhibited typical responses. Data not reported with side specificity (ie, only relative innominate rotations are calculated.

3. Cummings et al21 Artificial 10 Female college students; 19-23 y old. Relatively equal leg lengths (scanogram radiograph to rule out LLI >4 mm) and well-functioning SI joints. “Pelvometer”: handheld calipers with digital readout. Waterloo Spatial Motion and Recording Technique used to measure pelvic positional changes/2/8-7/8 in (6.35-22.23 mm) Plexiglass plates to create LLI Left lift caused posterior rotation of left innominate and anterior rotation of right innominate; dose related. Right lift caused posterior rotation of right innominate and anterior rotation of left innominate; dose related. Range: 1.62-5.73° of torsional spread from 6.35-22.23 mm of lift. Dose relationship reported, quite linear. Measurement tool tested vs radiograph showed validity of .97 ICC,3 intertester reliability of .95 ICC.3 Absolute values provided for left/right innominate rotation changes compared with baseline.

4. Beaudoin et al22 Artificial 20 Women, 19-24 y old, <5° scoliometer reading 3D motion analysis with reflective anatomical markers and 8 video cameras/15-mm shoe lift to create LLI Lifting right foot results in right posterior innominate rotation 1° ± 1.5°and 2° ± 1.4° anterior rotation on nonlifted side. Lifting left foot results in left posterior innominate rotation 1° ± 1.3°, and 2° ± 1.4° right anterior rotation. Changes with artificial LLI noted to be statistically significant. Only 1 lift size used; therefore, no dose effect reported.

5. Young et al23 Artificial 29 Healthy 18-to 28-y–old subjects (7 men). There were 21 without LLI, and 8 with preexisting > 1.8° lateral pelvic tilt Pelvic inclinometer with bubble/15- to 24-mm lift to create ≥ 1.2° lateral pelvic tilt. In 8 subjects with preexisting pelvic tilt, lift used to level pelvis. Lifting right leg results in 2.55° 0.58 mm relatively increased anterior rotation right ilium; lifting right leg results in 3.48° 0.52 mm relatively increased anterior rotation left ilium. Lifts did not reduce torsion in subjects with preexisting pelvic tilt. Pelvic sagittal tilt measurement reliability = 0.99 ICC3,4 with 0.52 standard error of measurement.

Data are provided for pre- and posttorsional spread, not for absolute changes in either anterior or posterior innominate rotation. Regression analysis not performed, although a provided scatter plot confirms a dose response.

6. Zabjeck et al24 Artificial 46 (Average age, 12 y) old scoliosis patients, 37 female; 14 evaluated radiologically Stereo videography of reflectors on anatomical landmarks/5-, 10-, or 15-mm lifts under left foot Innominate rotations observed with eft lift: 11% bilateral posterior rotation; 20% bilateral anterior rotation; 68% with pattern of right anterior and left posterior innominate rotation. For bilateral movements, the deltas, if any, were not reported. Lifts did seem to reduce torsion in subjects with preexisting pelvic tilt. Statistically significant changes are stated to be dose related, although data not reported by size of lift. Changes with lift reported as absolute values only, rendering interpretation difficult.

7. Hanada et al41 Artificial 14 Subjects (5 men), ≥19 y old, with <10 mm LLI for reliability study; 30 subjects for iliac crest comparison Open book placed under leg, page number noted that levels iliac crests. Termed ICPBC method. Book method understated known induced mean LLI by 3.8 ± 10.3 mm. Underestimated radiologically determined mean LLI by 5.1 ± 8.6 mm. Scatter plots provided for correlation of crest leveling and radiology with induced LLI. Summary data reported as mean values only. ICCs calculated. Investigators did not attempt to measure torsion, but results suggest torsion occurred (analogous to “dimple lag” of Drerup et al.20

8. Giles25 Natural Convenience sample of 100 radiographs, subjects 19-77 y old. 50 radiographs with >9 mm LLI, 50 radiographs with 0-3 mm LLI. Subjects with facet tropism disqualified. Radiograph measurement of left vs right lumbosacral facet angle using anteroposterior and oblique lumbopelvic films. LLI estimated from radiograph femoral head heights. No artificial LLI created. 50 Patients with a mean of 13.9 mm LLI “always” showed a smaller lumbosacral facet angle of the short leg side mean 64.7° vs 70.3° on long leg side, suggesting anterior rotation of ilium and sacrum on the side of the shorter leg. No artificial LLI created. Mann-Whitney test comparing the difference between the left and right measurements in both groups was highly significant, z value of 7.293 Note: Data do not distinguish whether there was an effect on 1 or both innominate bones.

9. Krawiec et al26 Natural 44 Male college athletes Pelvic inclinometer (PALM, aka Palpation Meter)/tape measure/TMMs used to measure LLI. No artificial LLI created. ICC calculated for LLI and torsion measurements (ICC = .99). 42 subjects (95%) had pelvic torsion; 73% were relatively right anterior (mean 1.9 ± 0.2.6°); 27% left anterior (mean not provided); 95% had LLI; 68% short right; mean 2.2 ± 7.3 mm using medial malleolus TMM and mean 1.4 ± 6.2 mm using lateral malleolus TMM/no artificial LLI created. Relating pelvic torsion to LLI: r = 0.33, P = .026 (med mall method); r = =0.44, P = .003 (lat mall method) TMM for LLI may not be very accurate. No threshold for identifying LLI provided. Correlations not very strong. Patient population not heterogeneous. Some other studies have shown baseline right posterior innominate rotation. Supine vs standing assessment of LLI noted as interpretive