The position of the lumbar vertebrae in relation to the intercrestal line.
OBJECTIVE
To determine the position of the lumbar vertebrae in relation to the intercrestal line and variation in distance between the midpoint of the L(4/5) interspinous space and the intercrestal line in varying patients age groups of Thai people.


METHODS
The present study was a retrospective analysis of the antero-posterior and lateral lumbosacral vertebral radiographs of 270 patients, varying patients' age from 20 to 80 years. Intercrestal line was drawn connecting the two highest points on the iliac crests of antero-posterior radiographs. The distance from the intercrestal line to the midpoint of the L(4/5) interspinous space and L(4/5) intervertebral space were measured. The results were statistically analysed by using ANOVA testing.


RESULTS
The intercrestal line crosses the midline of the posterior part ofthe lumbar vertebral column between the upper half of L4 spinous process level and lower half of L5 spinous process level, most often at the lower half of L4 spinous process level (101 cases, 37.41%). This line crosses the anterior part of the lumbar vertebral column between the upper half of L4 body level and lower half of L5 body level, most often at the upper half of L5 body level (103 cases, 38.15%). Regarding distance from intercrestal line to the midpoint of the L(4/5), interspinous space in varying patient age groups, the intercrestal line was most frequently found above the L(4/5) interspinous space in most age group (average 5.73 +/- 5.72 mm; value p > 0.05 vs. 70-80 years). For the distance from intercrestal line to the midpoint of the L(4/5) intervertebral space in varying patient age groups, the intercrestal line was most frequently found below the L(4/5) intervertebral space in all age groups (average 6.60 +/- 6.97 mm; value p > 0.05 vs. 70-80 years).


CONCLUSIONS
The intercrestal line crosses the posterior part of the lumbar vertebral column between the upper half of L4 spinous process level and lower half of L5 spinous process level, most often at the lower half of L4 spinous process level (37.41%) and at the L(4/5) interspinous space level (27.78%). This line crosses the anterior part of the lumbar vertebral column between the upper half of L4 body level and lower half of L5 body level, most often at the upper half of L5 body level (38.15%) and at the L(4/5) intervertebral space level (32.22%). The level of the intercrestal line tends to be high in elderly patients, neutral position and the intercrestal line by palpation tends to be identified at the higher level.
Department ofRadiology, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand.
Pisit
P
Wattanaruangkowit
Kajorn
K
Lakchayapakorn
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007085:Ilium / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D007403:Intervertebral Disc / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology; D008159:Lumbar Vertebrae / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D013785:Thailand; D055815:Young Adult