We studied the lumbar spines of 117 adults (39 women and 78 men) with spondylolysis unrelated to low back pain using multidetector computed tomography (CT). Of the 117 subjects with spondylolysis, including five with multiple-level spondylolysis, there were 124 vertebrae with spondylolysis. In adult lumbar spines with unilateral spondylolysis, there was no significant difference between the incidence of spondylolisthesis in female and male subjects. However, in those with bilateral spondylolysis, there was a significantly higher incidence of spondylolisthesis in female subjects (90.9%) than in males (66.2%). Furthermore, females with bilateral spondylolysis had significant more slippage than males. Lumbar index and lumbar lordosis were not significantly different between male and female subjects, and did not significantly correlate with slippage. In conclusion, to treat acute spondylolysis in adolescents, it is important to obtain bony union at least unilaterally, especially in female subjects, to prevent further slippage

Kondo, Tadashi

Nishitani, Hiromu

Sairyo, Koichi

Sakai, Toshinori

Takao, Shoichiro

Ueno, Junji

Yasui, Natsuo

Tokushima University Institutional Repository

INTRODUCTIONSpondylolysis is thought to be a stress fractureof the pars interarticularis that occurs frequently inadolescent sports players (1, 2). Some patients withspondylolysis concomitantly have various deformi-ties of the lumbosacral region, including slippageof the vertebral body (spondylolisthesis) and/orwedging deformity (1, 3-10). Saraste reported thatapproximately 80% of patients with spondylolysisshowed slippage, and in one-fifth of these patientsthe slippage exceeded 25% (11). Wedging deformityof the spondylolytic vertebra has been interpretedas an expression of the hypoplastic dysplasia andcommonly accepted as the cause of spondylolysisand spondylolisthesis. Sairyo et al. examined 46 ado-lescent athletes with symptomatic spondylolysis andreported that slippage at L5 was correlated with thematurity of the lumbar spine : slippage occurred inthe immature spine and ceased when the vertebramatured. Furthermore, they suggested that thewedge deformity of the affected vertebra might bea result rather than a cause of slippage (12).There have been reports that adolescent femaleshave a higher degree of slippage at diagnosis thanadolescent males (9, 13). There have been no re-ports of gender differences of these deformities as-sociated with spondylolysis in the general popula-tion. Here, we studied the lumbar spine in adultswith spondylolysis unrelated to low back pain usingORIGINALRadiographic comparison between male and femalepatients with lumbar spondylolysisShoichiro Takao1, Toshinori Sakai2, Koichi Sairyo2, Tadashi Kondo3, Junji Ueno1,Natsuo Yasui2, and Hiromu Nishitani41Department of Radiologic Science and Technology, 2Department of Orthopedics, 3Department of Medi-cal Imaging Informatics, and 4Department of Radiology, Institute of Health Biosciences, the Universityof Tokushima Graduate School, Tokushima, JapanAbstract : We studied the lumbar spines of 117 adults (39 women and 78 men) with spon-dylolysis unrelated to low back pain using multidetector computed tomography (CT). Ofthe 117 subjects with spondylolysis, including five with multiple-level spondylolysis, therewere 124 vertebrae with spondylolysis. In adult lumbar spines with unilateral spondy-lolysis, there was no significant difference between the incidence of spondylolisthesis infemale and male subjects. However, in those with bilateral spondylolysis, there was a sig-nificantly higher incidence of spondylolisthesis in female subjects (90.9%) than in males(66.2%). Furthermore, females with bilateral spondylolysis had significant more slippagethan males. Lumbar index and lumbar lordosis were not significantly different betweenmale and female subjects, and did not significantly correlate with slippage. In conclusion,to treat acute spondylolysis in adolescents, it is important to obtain bony union at leastunilaterally, especially in female subjects, to prevent further slippage. J. Med. Invest.57 : 133-137, February, 2010Keywords : spondylolysis, computed tomography, spondylolisthesis, gender differences, lumbar spinesReceived for publication November 26, 2009 ; accepted January12, 2010.Address correspondence and reprint requests to HiromuNishitani, MD, PhD, Department of Radiology, Institute of HealthBiosciences the University of Tokushima Graduate School, 3 -18-15 Kuramoto-cho, Tokushima 770-8503, Japan and Fax : +81-886-7174.The Journal of Medical Investigation Vol. 57 2010133multidetector computed tomography (CT), and fo-cused on gender differences.MATERIALS AND METHODSSubjectsA total of 117 patients (39 women and 78 men)with lumbar spondylolysis were included in thisstudy. Mean patient age was 63.0 (22 to 87) years.All patients also participated in our preliminary study(14). Patients underwent abdominal and pelvic CTwith a single multidetector CT scanner for reasonsunrelated to lower back pain. All CT scans wereordered from the departments of general surgeryand gynecology. Each CT was performed using a16-detector-row CT scanner (Aquilion 16 ; ToshibaMedical Systems, Tokyo, Japan) with a rotation timeof 0.5s, helical pitch 15 (beam pitch 0.9375), tubevoltage 120 kV, and tube current 10-400 mA (SD8.5). The acquired images were reconstructed intoCT images (thickness 1 mm) utilizing the CT imagereconstruction function of FC10 or FC 50. Observa-tion was performed using a 1-mm slice thicknessMPR (multi planer reconstruction) image withAquarius NET Server (TeraRecon, Inc ; San Mateo,CA, USA) under standard bone settings (windowwidth 2200, window level 200). S.T. (certified radi-ologist) and T.S.(certified spine surgeon) reviewedall images, and diagnosis and measurements wereachieved by consensus. An institutional review boardexemption was obtained for reviewing the imagingstudies along with the indications for the studies andthe official CT reports.MeasurementsIn the previous studies, measurements have beenmade using plain X-ray films ; there have been nopreviously defined criteria for using CT images forthese measurements. We measured degree of trans-lation (mm), slippage (%), lumbar index (%), andlumbar lordosis (degrees), which are thought to beassociated with spondylolysis. All measurementswere performed using mid-sagittal and mid-coronalsections (Figure 1).Degree of slippageMeasurements of degree (translation) of slippagewere conducted on mid-sagittal view (Figure 2-a).Percent slippage was measured according to themethod described by Wiltse and Winter (15).Lumbar indexLumbar index (LI) was measured on mid-sagittalview (Figure 2-b).Lumbar lordosisLumbar lordosis was measured from the supe-rior endplate of L1 to the superior endplate of S1(Figure 3).Figure 1. All measurements were performed using 1-mm slicethickness CT scans reconstructed with Aquarius NET Server,and using mid-sagittal and mid-coronal sections.Figure 2. (a) Measurements of degree (translation) of slip-page were conducted on mid-sagittal view. Percent slippage wasmeasured according to the method described by Wiltse andWinter (15).(b) Lumbar index was measured on mid-sagittal view.S. Takao, et al. Radiographic gender differences with the lumbar spondylolysis134Statistical analysisThe statistical analyses were performed usingcross tabulation (Fisher’s exact probability test),Mann-Whitney U test in comparisons of nonpara-metric variables, and Spearman’s rank correlationcoefficient test. The statistical difference was rec-ognized as significant, when the p value was lessthan 0.01.RESULTSIn the 117 patients with spondylolysis, includingfive with multiple-level spondylolysis, there were124 affected vertebrae. There were 26 vertebraewith unilateral spondylolysis and 98 vertebrae withbilateral spondylolysis.Of the 26 subjects with unilateral spondylolysis,nine were female (mean age : 60.915.4 years,range : 37-83 years) and 17 were male (mean age :67.414.4 years, range : 22-87 years). In the groupof 17 males, there were two subjects (11.8%) withslippage, whereas none (0%) of the nine females hadslippage. However, there was no statistically signifi-cant difference (Fisher’s exact probability test) be-tween these results (Table 1).Of the 98 subjects with bilateral spondylolysis,there were 33 females (mean age : 61.412.2 years,range : 35 - 83 years) and 65 males (mean age :63.114.4 years, range : 24 - 87 years). Of the 65male subjects there were 43 (66.2%) with slippage,whereas of the 33 female subjects there were 30(90.9%) with slippage. There was a statistically sig-nificant difference between the two groups (p0.01,Fisher’s exact probability test) (Table 2).In subjects with unilateral spondylolysis, transla-tion, percent slippage, lumbar index, and lumbar lor-dosis were not significantly different between maleand female subjects (Table 3). Whereas in thosewith bilateral spondylolysis, translation and percentslippage were statistically significantly greater in fe-males than in males (p0.01, Mann-Whitney Utest) (Table 4).In subjects with bilateral spondylolysis, there wasno correlation between age and slippage (translation,percent slippage) (Spearman’s rank correlation coef-ficient test) in either males or females. Additionally,there were no correlations between lumbar index orlumbar lordosis and slippage (translation, percentslippage).Figure 3. Lumbar lordosis was measured from the superiorendplate of L1 to the superior endplate of S1.Table 1.Unilateral Spondylolysis Men WomenSubjects with Slippage 2 (11.8%) 0 (0%)Subjects without Slippage 15 (88.2%) 9 (100%)Total 17 9Table 2.Bilateral Spondylolysis Men WomenSubjects with Slippage 43 (66.2%) 30 (90.9%)Subjects without Slippage 22 (33.8%) 3 (9.1%) *Total 65 33*p0.01, Fisher’s exact probability testTable 3.Unilateral Spondylolysis : 26 VertebraeMen (n=17) Women (n=9)Translation (mm) 0.411.17 0 N. S.Percent slippage (%) 1.263.45 0 N. S.Lumbar Index (%) 83.326.72 80.907.50 N. S.Lumbar Lordosis (degree) 52.238.23 49.2012.70 N. S.The Journal of Medical Investigation Vol. 57 February 2010 135DISCUSSIONIn adult lumbar spines with unilateral spondyloly-sis, there was no significant difference between theincidence of spondylolisthesis in male (11.8%) andfemale subjects (0%). However, in those with bilat-eral spondylolysis, there was a significantly higherincidence of spondylolisthesis in females (90.9%)than in males (66.2%). Slippage in patients withspondylolysis is thought to be most prevalent dur-ing the growth period and rare thereafter (8, 13).Sairyo et al. retrospectively reviewed immature pa-tients with spondylolysis to elucidate the relation-ship between the maturity of the lumbosacral spineand the development of slippage (12). They con-cluded that slippage was more prevalent in individu-als of a younger skeletal age, whose lumbar spinewas immature, and it ceased once the growth pe-riod was over and the vertebra had matured. Fromthese results, it appears that to treat acute spondy-lolysis in adolescence it is important to obtain bonyunion at least unilaterally, especially in female sub-jects.In the present study, female subjects with bilat-eral spondylolysis had significantly more slippagethan males. This result was consistent with previ-ous reports. It has previously been reported thatgirls have a greater degree of slippage at diagnosis(13, 16). Based on these results, we suggest that ayoung female patient with acute bilateral spondy-lolysis will have a predisposition to severe slippage.The etiology of this difference between males andfemales is unknown. Slippage of the lumbar spinewith spondylolysis occurs between the osseous andcartilaginous end plates because the site includingthe growth plate is the weakest link to anteriorshearing forces (17-20). Therefore, we speculatethat there is a gender difference in the fragility ofthe growth plate.Lumbar index (wedging deformity) and lumbarlordosis showed no significant difference betweenmale and female subjects. Furthermore, they didnot significantly correlate with slippage. Ikata et al.have reported that, in adolescents, wedging deform-ity was not evident if the pars defect was in the earlystages of development but the degree of deformityincreased as the stage of the pars defect advancedand as slippage developed (17). These results sug-gest that although the wedging deformity could cor-relate with slippage during the growth period, itdoes not affect the degree of slippage after matura-tion of the spine. There is controversy regardingpossible correlation between lumbar lordosis andslippage (21-24) ; consistent with the present study,some reports have demonstrated no correlation(23, 24).The main limitation of this study was that, as itis based on CT scans, slippage and lumbar lordosiswere evaluated under static conditions. Therefore,dynamic changes in slippage by lumbar flexion/extension were not evaluated, and lumbar lordosiswas not measured in the standing position.In conclusion, in subjects with bilateral spondy-lolysis, there was a significantly higher incidence ofspondylolisthesis in female subjects than in males.Furthermore, female subjects with bilateral spon-dylolysis had significantly more slippage than males.Therefore, to treat acute spondylolysis in adoles-cents, it is important to obtain bony union at leastunilaterally to prevent further slippage, especiallyin female subjects.REFERENCES1. Wiltse LL : The etiology of spondylolisthesis.J Bone Joint Surg Am 44 : 539-560, 19622. Sairyo K, Katoh S, Sakamaki T, KomatsubaraS, Endo K, Yasui N : Three successive stressfractures at the same level in an adolescentbaseball player. Am J Sports Med 31 : 606-610,20033. Wiltse LL, Newman PH, Macnab I : Classifica-tion of spondylolisis and spondylolisthesis. ClinTable 4.Bilateral Spondylolysis : 98 VertebraeMen (n=65) Women (n=33)Translation (mm) 4.063.41 5.642.90 *Percent slippage (%) 11.429.65 17.759.93 *Lumbar Index (%) 80.739.11 79.308.58 N. S.Lumbar Lordosis (degree) 51.007.92 52.0710.17 N. S.*p0.01, Mann-Whitney U testS. Takao, et al. Radiographic gender differences with the lumbar spondylolysis136Orthop Relat Res 117 : 23-29, 19764.. Farfan HF, Osteria V, Lamy C : The mechani-cal etiology of spondylolysis and spondylolis-thesis. Clin Orthop Relat Res 117 : 40-55, 19765. Krenz J, Troup JD : The structure of the parsinterarticularis of the lower lumbar vertebraeand its relation to the etiology of spondylolysis,with a report of a healing fracture in the neu-ral arch of a fourth lumbar vertebra. J BoneJoint Surg Br 55 : 735-741, 19736. Lafferty JF, Winter WG, Gambaro SA : Fatiguecharacteristics of posterior elements of verte-brae. J Bone Joint Surg Am 59 : 154-158, 19777. Morita T, Ikata T, Katoh S, Miyake R : Lum-bar spondylolysis in children and adolescents.J Bone Joint Surg Br 77 : 620-625, 19958. Fredrickson BE, Baker D, McHolick WJ, YuanHA, Lubicky JP : The natural history of spondy-lolysis and spondylolisthesis. J Bone Joint SurgAm 66 : 699-707, 19849. Boxall D, Bradford DS, Winter RB, Moe JH :Management of severe spondylolisthesis in chil-dren and adolescents. J Bone Joint Surg Am61 : 479-495, 197910. Seitsalo S, Osterman K, Poussa M, Laurent LE :Spondylolisthesis in children under 12 years ofage : long-term results of 56 patients treatedconservatively or operatively. J Pediatr Orthop8 : 516-521, 198811. Saraste H : Spondylolysis and spondylolisthesis.Acta Orthop Scand (Suppl 251) : 84-86, 199312. Sairyo K, Katoh S, Ikata T, Fujii K, Kajiura K,Goel VK : Development of spondylolytic olis-thesis in adolescents. Spine J 1 : 171-175, 200113. Seitsalo S, Osterman K, Hyvãrinen H, TallrothK, Schlenzka D, Poussa M : Progression ofspondylolisthesis in children and adolescents.A long-term follow-up of 272 patients. Spine(Phila Pa 1976) 1991 ; 16(4) : 417-21.14. Sakai T, Sairyo K, Takao S, Nishitani H, YasuiN : Incidence of lumbar spondylolysis in thegeneral population in Japan based on multide-tector computed tomography scans from twothousand subjects. Spine (Phila Pa 1976) 34 :2346-2350, 200915. Wiltse LL, Winter RB : Terminology and meas-urement of spondylolisthesis. J Bone Joint SurgAm 65 : 768-772, 198316. Danielson BI, Frennered AK, Irstam LK : Ra-diologic progression of isthmic lumbar spondy-lolisthesis in young patients. Spine (Phila Pa1976) 16(4) : 422-425, 199117. Ikata T, Miyake R, Katoh S, Morita T, MuraseM : Pathogenesis of sports-related spondylolis-thesis in adolescents. Radiographic and mag-netic resonance imaging study. Am J SportsMed 24 : 94-98, 199618. Kajiura K, Katoh S, Sairyo K, Ikata T, Goel VK,Murakami RI : Slippage mechanism of pediat-ric spondylolysis : biomechanical study usingimmature calf spines. Spine (Phila Pa 1976)26(20) : 2208-2212, 200119. Konz RJ, Goel VK, Grobler LJ, Grosland NM,Spratt KF, Scifert JL, Sairyo K : The path-omechanism of spondylolytic spondylolisthesisin immature primate lumbar spines in vitro andfinite element assessments. Spine (Phila Pa1976) 26(4) : E38-49, 200120. Sairyo K, Goel VK, Grobler LJ, Ikata T, KatohS : The pathomechanism of isthmic lumbarspondylolisthesis. A biomechanical study in im-mature calf spines. Spine (Phila Pa 1976) 23(13) : 1442-1446, 199821. Roussouly P, Gollogly S, Berthonnaud E,Labelle H, Weidenbaum M : Sagittal alignmentof the spine and pelvis in the presence of L5-S1isthmic lysis and low-grade spondylolisthesis.Spine (Phila Pa 1976) 31 : 2484-2490, 200622. Labelle H, Roussouly P, Berthonnaud E,Dimnet J, O’Brien M : The importance of spino-pelvic balance in L5-S1 developmental spon-dylolisthesis : a review of pertinent radiologicmeasurements. Spine (Phila Pa 1976) 30 (6Suppl) : S27-S34, 200523. Rajnics P, Templier A, Skalli W, Lavaste F,Illés T : The association of sagittal spinal andpelvic parameters in asymptomatic persons andpatients with isthmic spondylolisthesis. J SpinalDisord Tech 15 : 24-30, 200224. Hanson DS, Bridwell KH, Rhee JM, Lenke LG :Correlation of pelvic incidence with low- andhigh-grade isthmic spondylolisthesis. Spine(Phila Pa 1976) 27 : 2026-2029, 2002The Journal of Medical Investigation Vol. 57 February 2010 137

Radiographic comparison between male and female patients with lumbar spondylolysis

http://repo.lib.tokushima-u.ac.jp/files/public/6/65273/20170929141735763852/LID201112272001.pdf

Radiographic comparison between male and female patients with lumbar spondylolysis

Abstract

Similar works

Full text

Available Versions

Tokushima University Institutional Repository