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At least 19 recordsLinked to original sources
PubMed2003

The relationship between lumbar lordosis and radiologic variables and lumbar lordosis and clinical variables in elderly, African-American women.

Several authors have hypothesized that there is a link between lumbar lordosis and low back pain. These relationships have not been previously described in a sample consisting exclusively of elderly, African-American women. The purpose of this study was to describe the relationship between lumbar lordosis and radiologic variables and lumbar lordosis and clinical variables in elderly, African-American women. A total of 475 African-American women enrolled in the multicenter Study of Osteoporotic Fractures participated in this ancillary, cross-sectional, study of lumbar lordosis. These women received lumbar spine radiographs and completed a questionnaire on low back pain and its impact on their daily lives. Lumbar lordosis tertiles were created based on radiographic measurements. Comparisons were made between the tertiles for differences in radiologic and clinical variables. Significant differences (p < 0.0025) were observed between the lordosis tertiles and the presence of spondylolisthesis, intervertebral disc space, and vertebral wedging. No significant differences were observed between the lordosis tertiles for the occurrence of low back pain, symptoms associated with low back pain, and disability experienced from low back pain. The degree of lumbar lordosis was associated with radiologic variables but was not associated with symptoms or decreased function from low back pain. These findings question the clinical utility of the lumbar lordosis measurement in elderly, African-American women.

Aged↗
PubMed1991

Oxytocin effects on lordosis frequency and lordosis duration following infusion into the medial pre-optic area and ventromedial hypothalamus of female rats.

When infused into the medial preoptic area of ovariectomized female rats treated with estradiol benzoate (3 micrograms) and progesterone (150 micrograms), oxytocin was found to increase the lordosis frequency and the lordosis duration. Oxytocin administered into the ventromedial hypothalamus increased the lordosis duration but not the lordosis frequency. In the mesencephalic central grey, oxytocin did not significantly affect lordosis. Oxytocin in the ventromedial hypothalamus facilitated lordosis duration at doses which were ineffective in the medial preoptic area. This contrasts with the pattern of results observed for lordosis frequency. These results lend support to the hypothesis that the lordosis-facilitating actions of oxytocin in the ventromedial hypothalamus are due to a permissive effect of progesterone and that the ventromedial hypothalamus and medial pre-optic area may control different aspects of lordosis.

Animals↗
PubMed1993

Idazoxan decreases estrogen-induced lordosis in female but not "hormone-independent" lordosis in male guinea pigs of an inbred strain.

This experiment examined whether the imidazoline idazoxan (which binds to alpha-noradrenergic receptors and to imidazoline-preferring sites) interferes with hormone-dependent or hormone-independent lordosis responses. Ovariectomized (ovx) Strain 2 female guinea pigs which were sexually receptive after receiving estradiol benzoate (EB; 3 micrograms/d for 3 days) were injected with either idazoxan (10 mg/kg) or with vehicle at 24 hr after the last EB injection. Idazoxan significantly decreased EB-facilitated lordosis responses in these females. Castrated Strain 2 males, which show lordosis behavior without gonadal hormone administration, were injected with the same dosage of idazoxan (10 mg/kg) or with vehicle. Idazoxan did not inhibit lordosis behavior in these males.

Adrenergic alpha-Antagonists↗
PubMed1999

Indomethacin inhibits lordosis induced by ring A-reduced progestins: possible role of 3alpha-oxoreduction in progestin-facilitated lordosis.

Progestins with a delta-4-3-keto configuration bind to the progestin receptor (PR) and facilitate estrous behavior in estrogen-primed rats. Some ring A-reduced progestins [5alpha-dihydroprogesterone (alphaDHP), allopregnanolone, and epipregnanolone] are more potent estrus-inducing agents than progesterone when iv injected despite their lower affinity for the PR. Yet the estrus-inducing action of such progestins is reduced by the antiprogestin RU486, suggesting that binding to the PR is required for this effect. Because allo- and epi-pregnanolone are oxidized to alpha- and betaDHP, respectively, by 3alpha-hydroxysteroid oxo-reductase (3alphaHSOR), part of their estrus-inducing action may occur through the binding of such DHPs to the PR. Conversely, because 3alphaHSOR reduces alpha- and betaDHP to allo- or epi-pregnanolone, both of which exert membrane effects, the estrus-inducing effect of DHPs may involve actions independent of the PR. To test these possibilities we assessed the effect of indomethacin, a blocker of 3alphaHSOR, on the estrus-inducing action of such progestins. Because indomethacin also inhibits cyclooxygenases, we selected a dose and treatment schedule that does not interfere with prostaglandin-mediated brain processes (e.g., LHRH release). Indomethacin did not significantly modify the effect of progesterone or megestrol acetate on lordosis. Yet, it significantly reduced the action of all ring A-reduced progestins. Results suggest that: (a) oxidation is essential for lordosis facilitation by 3alpha-pregnanolones and (b) reduction of 3-keto progestins generates 3alpha-hydroxy metabolites which synergize with processes triggered by occupation of the PR by 3-keto progestins. The possible participation in this response of other events influenced by indomethacin (e.g., prostaglandin or melatonin synthesis) is discussed.

3-Hydroxysteroid Dehydrogenases↗
PubMedDate not supplied

Measurements of lumbopelvic lordosis using the pelvic radius technique as it correlates with sagittal spinal balance and sacral translation.

BACKGROUND CONTEXT: Maintenance of normal lumbar lordosis is important in the treatment of spinal disorders. Many attempts have been made to quantify normal sagittal spinal alignment and lordosis using a C7 plumb line and segmental angulations of the spinal vertebrae. Little attention has been given to pelvic compensation as it correlates to lumbar lordosis and overall sagittal spinal alignment. Better methods of measuring lordosis, which correlate with sagittal spinal balance and pelvic compensation, are needed in treating patients with spinal disorders. PURPOSE: To determine the correlation between lumbopelvic lordosis, pelvic rotation and sagittal spinal balance and standardize a method for measuring lumbopelvic lordosis, sacral translation, and sagittal spinal alignment. STUDY DESIGN: Sagittal alignments using the C7 plumb line, Cobb angles, sacral plumb line and the pelvic radius (PR) technique were used to measure standing 36-inch lateral radiographs of patients with various spinal disorders. PATIENT SAMPLE: A review of the records identified 62 patients with various spinal pathologies presenting to the (RGW) spine clinic that had standing lateral spine radiographs. Only radiographs that allowed positive identification of the C7 vertebral body, the entire thoracolumbar spine, the sacrum and both femoral heads were studied. These criteria allowed inclusion of 28 subjects in this study. The final population had 12 women and 16 men with an average age of 52 years (SD, 16.6 years; range, 20 to 84 years). OUTCOME MEASURES: No outcomes measures were used in this study. METHODS: Measurements for sagittal spinal balance and lumbopelvic lordosis were made on 36-inch standing lateral radiographs of adult patients. Measurements included the C7 plumb line, segmental angulations of spinal vertebrae (Cobb angles), sacral translation and the PR technique for lumbopelvic lordosis. Data were analyzed for significant correlation between lumbopelvic lordosis, sagittal spinal balance, sacral translation and total segmental lumbar lordosis using the Cobb method. RESULTS: Our population averaged 50 degrees of total segmental lumbar lordosis from L1 to S1 (SD, 14.3; maximum, 89.5; minimum, 17.9). Nearly 75% of total segmental lumbar lordosis measured from L1 to S1 can be accounted for through the L4 to S1 superior end plates and 47% through L5 to S1 superior end plates in our population. Total segmental lumbar lordosis correlated with total thoracic kyphosis (r=0.45, p=.008). Total segmental lumbar lordosis measured by the Cobb method significantly correlated with sagittal spinal balance (r=-0.35, p=.022) and sacral translation (r=0.41, p=.016). Measurements for lumbopelvic lordosis significantly correlated with sagittal spinal balance (r=-0.33, p=.042), sacral translation (r=-0.70, p=.00002) and total segmental lumbar lordosis (r=0.82, p<.000001). Measurements for sacral translation and sagittal spinal balance also correlated significantly (r=0.35, p=.034). CONCLUSIONS: Sacral translation, the C7 plumb line and lumbopelvic lordosis are useful measures for sagittal spinal balance. Lumbopelvic lordosis and sacral translation can be correlated to the sagittal spinal balance. Understanding these measurements and the range of lumbopelvic compensation can be extremely helpful in treating patients with spinal pathology and in avoidance of flatback deformity. Application of these measures would be especially helpful in the treatment of patients with spinal fusion, degenerative spondylosis, disc disease, fractures, and in the prevention of sagittal malalignment.

Adult↗
PubMed1997

The effect of intraoperative hip position on maintenance of lumbar lordosis: a radiographic study of anesthetized patients and unanesthetized volunteers on the Wilson frame.

STUDY DESIGN: The effect of intraoperative hip position on maintenance of lumbar lordosis was evaluated radiographically in 13 anesthetized patients and 14 unanesthetized volunteers positioned on a Wilson frame (MDT Corp., Torrance, CA). OBJECTIVES: To evaluate the effect of hip position on total and segmental lumbar lordosis in patients and volunteers in standardized positions: standing and with hips extended and flexed on a Wilson frame. SUMMARY OF BACKGROUND: Preservation of lordosis during instrumented lumbar fusion is critical for maintenance of normal sagittal alignment. It is customary to extend the hips on certain positioning devices to maximize lordosis maintenance. However, little information exists concerning the degree to which this actually affects lumbar lordosis. Further, the question of how individuals are specifically affected intraoperatively by differences of position on the same device remains unanswered. METHODS: Preoperative standing and intraoperative lateral lumbar spine radiographs with patients' hips in standardized flexed and extended positions were obtained (n = 13). Similar radiographs were obtained of asymptomatic volunteers (n = 14). Lumbar lordosis (L1-S1) and intervertebral body angles at each level were measured. Data were analyzed for changes in total and segmental lordosis between standing and intraoperative positions for all subjects. RESULTS: In the patient group, 95% of preoperative standing lordosis was maintained with the patients' hips extended. With hips flexed from 19 degrees to 48 degrees (mean, 33 degrees), 74% of lordosis was maintained. In the volunteer group, 98% of standing lordosis was maintained with volunteers' hips extended; with their hips flexed 20 degrees to 36 degrees (mean, 28 degrees), 86% of lordosis was maintained. CONCLUSIONS: Hip flexion was associated with a significant decrease in lordosis in patients and volunteers. Positioning in maximal hip extension optimizes lordosis preservation. While other devices have been shown to have specific effects on lordosis, the Wilson frame can permit easy adjustment of the lumbar sagittal contour to facilitate either preservation or reduction in lordosis.

Adult↗
PubMed2003

Pelvic lordosis and alignment in spondylolisthesis.

STUDY DESIGN AND OBJECTIVES: Pelvic morphology and lumbopelvic lordosis were measured on standing radiographs of 75 patients with greater than 10% L5-S1 spondylolytic spondylolisthesis. The findings were compared with those of 75 volunteers to determine significant differences between the two groups. SUMMARY OF BACKGROUND DATA: Etiology of isthmic (lytic) spondylolisthesis remains uncertain. Causation appears to be multifactorial. The relationship between pelvic morphology and spondylolisthesis deserves additional study. METHODS: Both groups had a standing lateral radiograph of the thoracolumbar spine and pelvis taken that included both hips. Three radiographic angles for pelvic morphology (pelvisacral, pelvic incidence, and pelvic lordosis) were measured by two observers. Each offered similar reliability. Measurement of the pelvic lordosis angle by the pelvic radius technique required fewer steps. It also allowed calculation of the combined angles comprising both the pelvic morphology component for lordosis (the constant pelvic lordosis angle) and the lordosis in the lumbar spine (the variable lumbar lordosis from T12-S1) that should complement the fixed pelvic lordosis (the complementary lumbopelvic lordosis). Mean values and statistical correlations were then computed for each group and compared. RESULTS: The mean slippage for patients was 30% (range, 11-85%), with 34 patients (45%) having Grade I slips, 32 (43%) having Grade II slips, and nine (12%) having Grade III and IV slips. The mean measurements between patients and volunteers were significantly different (P < 0.01) for lumbar lordosis, pelvic lordosis, and lumbopelvic lordosis. Subgroups of patients with increasingly larger slips (Grade I-III) had significantly smaller mean angles for pelvic lordosis. CONCLUSIONS: The pelvic and lumbopelvic parameters studied were different in patients compared with controls. The contribution of the pelvis to lordosis was significantly smaller in the subgroups of patients with increasingly larger grades of spondylolisthesis. Pelvic morphology may play a role in the development of spondylolisthesis. Measurement of the combined lumbar and pelvic (lumbopelvic) lordosis on standing radiographs is important.

Adolescent↗
PubMed1995

The effect of operative position on lumbar lordosis. A radiographic study of patients under anesthesia in the prone and 90-90 positions.

STUDY DESIGN: The effect of intraoperative positioning on lumbar lordosis was retrospectively studied by radiographic analysis of 40 patients under general anesthesia. OBJECTIVES: The aim of this study was to document changes in segmental and total lumbar lordosis between preoperative standing and intraoperative radiographs taken in the "90-90" and prone positions. SUMMARY OF BACKGROUND: Preservation of physiologic lordosis was an important consideration in reconstructive lumbar spine surgery. To avoid iatrogenic loss of lordosis when using spinal instrumentation and to facilitate decompressive procedures, it was necessary to understand how segmental alignments were affected by intraoperative positioning. Although many positioning techniques were used, the effect on lumbar lordosis was not well established. METHODS: Preoperative (standing 36" lateral spine) and intraoperative radiographs (lateral lumbar spine L1 to the sacrum) in either the "90-90" position on a Hastings frame (n = 20) or the prone position on a Jackson table (n = 20) were measured twice by two independent observers using Cobb methodology for total and segmental lordosis between L1 and S1. Data were analyzed for intra- and interobserver reliability and changes in segmental and total lordosis between standing and intraoperative radiographs. RESULTS: Analysis of intra- and interobserver reliability revealed measurements were accurate and reproducible. The "90-90" position produced significant loss (P < or = 0.01) of total and segmental lordosis at all levels except L1-L2, which showed no change. Segmental lordosis was reduced nearly 60% at L2-L3, L3-L4, and L4-L5, and total lordosis was reduced by more than 35%. The prone position on the Jackson table increased segmental lordosis at L5-S1 by 22% (P < or = 0.01) and preserved total and segmental standing lordosis at all other levels. CONCLUSIONS: The "90-90" position on the Hastings frame was associated with significant reduction of total and segmental lordosis in the middle and lower lumbar spine. Positioning prone on a Jackson table maintained standing lumbar lordosis and increased lumbosacral lordosis.

Adult↗
PubMed1995

Endocrine basis for two types of individual differences in lordosis reflex intensity.

We have identified individual differences in two independent types of lordosis reflex intensity. Overall lordosis reflex intensity, averaged across 9.4 +/- 0.99 days (range = 1-18 days), differs among cycling individuals and is a biomarker for the rate and pattern of reproductive aging. Although estrogen is necessary to permit lordosis reflex responding and manifests individual differences throughout the estrous cycle, it was individual differences in progesterone that correlated negatively with the individual variation in overall lordosis reflex intensity; females with intense overall lordosis reflexes had low progesterone throughout the estrous cycle. Independent of their overall reflex intensity, females also displayed individual variation in lordosis reflex intensity on proestrus. Among females that still maintained a cyclic lordosis reflex, those with intense lordosis reflexes on proestrus had high levels of luteinizing hormone (LH) at lights out. Among females that displayed intense lordosis reflexes throughout the estrous cycle (i.e., had entered constant lordosis), those with intense proestrous lordosis reflexes had low levels of LH at lights out on proestrus. Females who had entered constant lordosis tended to have lower overall progesterone than females who still maintained cyclic patterns of lordosis. Thus, constant lordosis was identified as an important component of the changes of reproductive aging.

Animals↗
PubMed1996

Lumbar lordosis in spinal fusion. A comparison of intraoperative results of patient positioning on two different operative table frame types.

STUDY DESIGN: One hundred one patients undergoing spine surgery for degenerative conditions were entered into a prospective radiographic evaluation of changes in lumbar lordosis as affected by positioning on two different operative tables. OBJECTIVES: The hypothesis of the present study is twofold: 1) the positioning of patients on specific types of operative tables may affect significantly the overall degree of lumbar lordosis obtainable, and 2) certain operative positioning may more accurately reproduce physiologic standing lateral lumbar lordosis. SUMMARY OF BACKGROUND DATA: In the management of degenerative and post-traumatic spinal deformities, lumbar fusion using posterior instrumentation permits more accurate and physiologic lordotic positioning of the involved fusion segments of the lumbar spine. However, various types of operating frames are available for use in this type of surgery, and despite the overall importance of correct lordotic positioning, there is some question as to what effect on positioning, as measured in degrees of lumbar lordosis, a particular frame might have. METHODS: Total, multisegmental, and unisegmental Cobb angle measurements of preoperative standing lateral radiographs and intraoperative lateral radiographs after positioning on respective operative tables were determined. Fifty-one patients were positioned on an Andrews-type table, and 50 patients were positioned on the four-poster-type frame. Statistical comparison using analysis of variance testing of changes in lordosis before and after surgery between study groups was evaluated. RESULTS: Lumbar lordosis measured from L1 to S1 with standing lateral radiographs showed a combined mean preoperative measurement of 45.18 degrees, with no statistical significance between groups. In comparison, there was a statistically significant difference between intraoperative measurements from L1 to S1 on the Andrews table versus the four-poster frame, revealing an average of 32.81 degrees versus 47.71 degrees, respectively (P < 0.005). Multisegmental lordosis measurement from L2 to S1 displayed statistical significance between groups, with a combined preoperative standing lateral radiograph average of 43.32 degrees, and intraoperative values of 31.28 degrees on the Andrews table versus 45.34 degrees on the four-poster frame (P < 0.005). Multisegmental lordosis measurements from L4 to S1 displayed statistical significance between groups, with a combined preoperative standing lateral radiograph average of 31.40 degrees and intraoperative values of 23.14 degrees on the Andrews table versus 32.94 degrees on the four-poster frame (P < 0.005). Segmental lordosis at L5-S1 was less dependent on frame type, with a combined preoperative standing lateral radiograph average of 20.53 degrees and intraoperative measurements of 20.06 degrees on the Andrews table versus 21.02 degrees on the four-poster frame (P < 0.43). CONCLUSION: Results from the present study display a statistically significant difference between multisegmental and total lumbar lordosis, depending on the type of operative table used in patient positioning. Segmental lordosis at L5-S1 depended less on frame type. This table-dependent positional change in lumbar lordosis could be incorporated easily into a lumbar fusion procedure, especially when supplemented with instrumentation, affecting the permanent overall degree of lordosis. These results suggest that a more physiologic degree of lumbar lordosis is obtained accurately with use of an operative table similar to the four-poster frame.

Equipment Design↗
PubMed2001

Effects of lifestyle and work-related physical activity on the degree of lumbar lordosis and chronic low back pain in a Middle East population.

The relationship between the degree of lumbar lordosis and chronic low back pain (LBP) has long been speculated. It is postulated that prolonged sitting and sedentary lifestyle might change the degree of lumbar lordosis and cause LBP. The purpose of this study was to determine the effects of lifestyle, exercise, work setting, work intensity, and other demographic factors such as age, height, weight, and gender on the degree of lumbar lordosis and occurrence of LBP. Eight hundred forty subjects between ages 20 and 65 years were equally categorized into four groups: normal male, normal female, males with LBP, and females with LBP. A questionnaire was used to obtain information about the subject's lifestyle, work setting, level of exercise, and work-related physical activity. A flexible ruler was used to measure lumbar lordosis in all subjects. The average degree of lumbar lordosis for all subjects was 37 degrees +/- 13 degrees. Females had greater lumbar lordosis (42 degrees +/- 15 degrees ) than males did (32 degrees +/- 10 degrees ). There was no significant difference in the degree of lumbar lordosis in subjects with different lifestyle (p = 0.97), level of physical activity (p = 0.36), work setting (p = 0.5), and with or without LBP (p = 0.28). The degree of lumbar lordosis was positively related with the number of pregnancies (p = 0.04, r = 0.25), age (p = 0.02, r = 0.1) and height (p = 0.0001, r = 0.31) and negatively related with weight (p = 0.04, r = 0.06) of the subjects. The likelihood of developing LBP was significantly higher in the subjects who had high work-related physical activity (p = 0.03) and those who exercised less often (p = 0.008). We found no significant relationship between LBP occurrence and the degree of lumbar lordosis (p = 0.68), work setting (p = 0.15), height (p = 0.08), weight (p =0.06), and age (p = 0.67) of the subjects. The degree of lumbar lordosis was not different between normal subjects and those with LBP. Lumbar lordosis was not affected by lifestyle, level of physical activity, or type of work setting. Although these factors have not been found to affect the degree of lumbar lordosis, some affected the occurrence of LBP. This finding indicates that the effect of these factors on LBP involves mechanisms other than changing the degree of lumbar lordosis.

Adult↗
PubMed2003

[Geometrical and mechanical analysis of lumbar lordosis in an asymptomatic population: proposed classification].

PURPOSE OF THE STUDY: The main objective of this study was to describe the morphology and the mechanism underlying the organization of lumbar lordosis in terms of position and shape of the pelvis. A classification of lumbar lordosis was proposed based on the orientation of the sacral plane. MATERIAL AND METHODS: One hundred sixty asymptomatic young adult volunteers were x-rayed in a standardized standing position. A dedicated software was used for analysis of the spine and pelvis. The pelvic parameters were: pelvic incidence, sacral slope, pelvic tilt. The point separating thoracic kyphosis and lumbar lordosis was called the inflexion point. Lumbar lordosis was bounded by the sacral plate and the inflexion point. At the apex, the lumbar curve was divided into two tangent arcs of circle, quantified by an angle and the number of included vertebrae. The lower arc was geometrically equal to the sacral slope. Regarding the vertical line, a lordosis tilt angle was drawn between the inflexion point and the frontal limit of the sacral plate. RESULTS: The value of the lumbar lordosis was very variable. The best correlation was between lumbar lordosis and sacral slope, then between sacral slope and pelvic incidence. The upper arc of a circle remained constant while the lower arc changed with sacral slope. Good correlations were found between the sacral slope and the position of the apex and between sacral slope and lordosis tilt angle. DISCUSSION AND CONCLUSION: Regarding sacral slope, lumbar lordosis can be classified into four types. When the sacral slope is low, lumbar lordosis can either be both short and curved with a low apex and a backward tilt (type 1) or both long and flat with a higher position of the apex (type 2). When the sacral slope increases, lumbar lordosis increases in angle and number of vertebrae with an upper apex, with a progressively forward tilt (types 3 and 4). Depending on the shape and position of the pelvis, and because of the relation between sacral slope and pelvic tilt, the morphology of lumbar lordosis could be the main mechanical cause of degenerative diseases of the lumbar spine.

Adult↗
PubMed1993

Hormonal modulation of the cutaneous initiation of lordosis in infant and adult rats.

The purpose of these experiments is to compare the regional specificity (Experiment 1) and the hormonal modulation (Experiment 2) of the cutaneous initiation of lordosis in 4- to 6-day-old male and female rats (infants) and in 60- to 90-day-old female rats (adults). In Experiment 1, subjects were primed with 100 micrograms estradiol benzoate (EB) and 0.5 mg progesterone (P) and were denervated on the Waist (dermatomes L1-L3), Midriff (dermatomes T10-L3), Flanks (dermatomes L4-L6), or Sides (dermatomes T10-L6). In infants, there were no significant differences between males and females. Denervation of the Waist, Midriff, or Sides but not of the Flanks significantly decreased the percentage of subjects displaying lordosis, lordosis quotient (LQ), and mean lordosis duration; no significant differences were obtained among Waist-, Midriff, or Sides-denervated infants. In contrast, denervation of the Sides but not of the Waist significantly decreased LQ and mean lordosis intensity among adults. In Experiment 2, Waist-denervated infants and their surgical Controls were treated either with 100 micrograms EB and 0.5 mg P or with the oil vehicle; Waist-denervated adults and their surgical Controls received either 100 or 10 micrograms EB (no P). Regardless of hormone treatment, denervation of the Waist significantly decreased LQ and lordosis duration in infants and decreased LQ and lordosis intensity in adults. In infants, the only effect of priming with EB and P was to increase the percentage of pups showing lordosis and lordosis duration among the surgical Controls. In contrast, priming with 100 micrograms EB significantly increased the percentage of rats displaying lordosis, LQ, and lordosis intensity among Waist-denervated adults. These data suggest that cutaneous input from the Waist is important for eliciting lordosis in both infant and adult rats, and that the importance of this input is modulated by hormone priming in adult but not infant rats.

Animals↗
PubMedDate not supplied

Prevalence of hyperplastic articular pillars in the cervical spine and relationship with cervical lordosis.

BACKGROUND: Cervical lordosis is often used as an indicator for a number of clinical conditions ranging from traumatic to degenerative. Previous research has indicated that a number of factors may change the lordosis. However, the link between hyperplastic articular pillars and cervical lordosis measurements has never been studied. OBJECTIVE: To investigate the reliability of determining articular pillar hyperplasia, to determine its prevalence, and to compare lordosis measurements between persons with and without hyperplasia of the cervical articular pillars. METHODS: Twelve normal neutral lateral cervical radiographs were chosen for the reliability study. Two chiropractors independently evaluated the articular pillars of C3 through C6 by drawing lines along the planes of the superior and inferior articular surfaces of each pillar. Each pillar was categorized as "normal" or "hyperplastic" depending on the convergence or divergence of these lines. One examiner repeated this procedure after a 1-month interval. Percent agreement and kappa statistics were calculated for interexaminer and intraexaminer agreement. Forty-eight normal neutral lateral cervical radiographs with a horizontal Chamberlain's line were evaluated for the presence or absence of pillar hyperplasia. Two measurement techniques were used to assess the cervical lordosis: the method of Jochumsen and the "angle of the cervical lordosis." The unpaired t test was used to compare the angle of cervical lordosis measurements between the two groups. The Mann-Whitney U test was used to analyze data obtained with the method of Jochumsen. The prevalence of pillarhyperplasia was calculated on 100 normal lateral cervical radiographs. RESULTS: Interexaminer and intraexaminer reliability of determining pillar hyperplasia was fair to substantial (kappa = 0.4 to 0.61; 75% to 92%). Forty-six percent of the patients demonstrated pillar hyperplasia of at least one cervical level. Patients with pillar hyperplasia had a mean cervical curve of 31.52 degrees, whereas the curve in patients without pillar hyperplasia was 44.76 degrees (P = .0001). The method of Jochumsen also detected a significant difference in the curve measurements between the two patient groups (P = .0127). CONCLUSION: Articular pillar hyperplasia is common and significantly reduces the cervical lordosis measurements. Accepted normal values for lordosis evaluation need to be reassessed and articular pillar configuration considered when treatment plans include attempts to restore a "normal" cervical lordosis. Previous studies attempting to link lordosis measurements with pathologic conditions or symptoms may need to be reevaluated.

Cervical Vertebrae↗
PubMed1998

Compensatory spinopelvic balance over the hip axis and better reliability in measuring lordosis to the pelvic radius on standing lateral radiographs of adult volunteers and patients.

STUDY DESIGN: Sagittal alignments, including lumbar lordosis and spinopelvic balance (measured from C7, S1, and hip axis reference points for the relative positions of the spine and sacropelvis over the hips), were studied on standing 36-in. lateral radiographs of adult volunteers (control subjects) and patients who had specific spinal disorders. OBJECTIVES: To determine the most reliable methods for measuring lumbopelvic lordosis and to define significant spinopelvic compensations for sagittal balance. SUMMARY OF BACKGROUND DATA: Measurements for standing sagittal balance, obtained using a C7 plumb line, and segmental angulations of the spinal vertebrae, including lordosis to the sacrum, have been reported. Absolute values, even for normative data, have had wide variation and limited clinical usefulness. Correlations of sagittal balance with the reported spinopelvic angulations (spinal vertebral and sacropelvic angulations) have not been well defined. In addition, determinates of balance (spinal and pelvic) have not been studied for reliability, and compensatory mechanisms for maintenance of balance have not been carefully evaluated. Better recognition of the correlations and more reliable methods to measure lordosis and balance and the spinopelvic compensations for its maintenance may be beneficial in treating patients who have spinal disorders. METHODS: Measurements on standing 36-in. lateral radiographs were made for sagittal alignments in adult volunteers (n = 50) and in adult patients who had symptomatic degenerative lumbar disc disease (n = 50), low grade L5-S1 isthmic (lytic) spondylolisthesis (n = 30), and idiopathic or degenerative scoliosis (n = 30). All participants exhibited clinical compensation for balance. Data were analyzed for significant correlations within each group to determine compensatory correlations of spinopelvic balance with the other sagittal alignments. Intraobserver and interobserver reliability for the parameters evaluated were calculated. This included two methods for determining lordosis (S1 end-plate and pelvic radius techniques). RESULTS: Plumb line measurements for balance from the S1 and hip axis reference points, as defined, were similar in all four groups. However, the groups appeared to adjust for balance by using common and distinctive spinopelvic compensations that resulted in significantly and characteristically different angular alignments among the four groups. Lordosis and balance measurements were closely correlated, and the correlation was characterized by pelvic rotation and translation around the hip axis. The subjects with less lordosis typically stood with the C7 plumb line anterior to and at a longer distance from the sacral reference point. This was primarily because of posterior sacropelvic translation around the hip axis and not because the sagittal plumb line initially moved anteriorly away from the sacrum. This was true in all four groups and gave the appearance that the sacropelvis was less well balanced over the hips in the subjects with less lordosis. Even small differences in lordosis appeared to be associated with considerable adjustments in the other spinopelvic alignments. Therefore, it was important to determine that lordosis was lumbopelvic more reliably measured by the pelvic radius technique. CONCLUSIONS: Lower lumbar lordosis, by the pelvic radius technique, and compensatory sacropelvic translation around a hip axis, in addition to measurements from this axis to the C7 plumb line, were the primary determinates and most reliable radiographic assessments for sagittal balance. Understanding the common and characteristically different compensations that occur with balance in these patients who had specific spinal disorders may help to improve their care.

Adult↗
PubMed1999

Vertebral centroid measurement of lumbar lordosis compared with the Cobb technique.

STUDY DESIGN: An observational study in which vertebral centroid measurement of lumbar lordosis, developed in this study, was used to examine lumbar curvature. The intra- and interobserver reliability of the vertebral centroid measurement of lumbar lordosis and the Cobb technique were compared. OBJECTIVES: To evaluate the reliability of a new method of measuring lumbar lordosis and to examine the changes in the lordotic curve from 0 degree to 90 degrees flexion of the trunk. SUMMARY OF BACKGROUND DATA: Several different methods are used to measure lumbar lordosis. The Cobb technique, based on measurement of vertebral endplates, is the method most frequently adopted for clinical diagnosis. However, because of the variations in the vertebral endplate architecture, the vertebral surface angle is difficult to identify. This reduces the reliability of the Cobb technique. METHODS: Lateral radiographs of 16 study participants were taken from the upright position to a trunk flexion of 90 degrees in 30 degrees increments. The lumbar lordotic curve was measured by three observers individually using two applications of the traditional Cobb technique and the vertebral centroid measurement of lumbar lordosis. RESULTS: Correlation coefficients of lumbar lordosis between the two methods ranged from 0.589 to 0.772 with participants standing upright (all P < 0.05). Interobserver reliability coefficients were 0.903 for vertebral centroid measurement of lumbar lordosis, 0.826 for Cobb (L1-L5), and 0.784 for Cobb (L1-S1), although the three measurements all revealed an excellent intraobserver reproducibility (r greater than 0.9). The vertebral centroid measurement of lumbar lordosis showed the smallest mean absolute differences between any two observers' measurements (< 1.7 degrees). CONCLUSIONS: The findings from this study indicate that the vertebral centroid measurement of lumbar lordosis is more reliable than the Cobb method for assessing lumbar lordosis. The vertebral centroid measurement of lumbar lordosis also can be used to evaluate the actual lumbar curvature in outline at various angles of trunk flexion.

Adult↗
PubMed1985

Modulation of lordosis behaviour in the female rat by corticotropin releasing factor, beta-endorphin and gonadotropin releasing hormone in the mesencephalic central gray.

A possible functional relationship between corticotropin-releasing factor (CRF) and opiate peptide neuronal systems (beta-endorphin, dynorphin1-17 and Met-enkephalin) and their interactions with gonadotropin releasing hormone (GnRH) in the mesencephalic central gray (MCG) for the regulation of lordosis behaviour was assessed in ovariectomized, oestrogen-treated and oestrogen-progesterone-treated female rats. Lordosis behaviour triggered by male mounting was inhibited in a dose-dependent fashion by CRF microinfused into the MCG in both oestrogen-treated and oestrogen-progesterone-treated female rats. This CRF-induced inhibition of lordosis could be overcome by a pre-infusion of naloxone or anti-beta-endorphin-globulin (anti-beta-end-G) directly into the MCG but not by anti-Met-enkephalin globulin (anti-enk-G) or anti-dynorphin1-17 globulin (anti-dynor-G). Supporting data indicate that the facilitation of lordosis behaviour induced by treatment with naloxone or anti-beta-end-G alone but not with anti-enk-G or anti-dynor-G may be due to enhanced GnRH release. This results from the action of these substances in overcoming the inhibition of GnRH secretion mediated specifically by beta-endorphin but not by Met-enkephalin or dynorphin1-17 in the MCG. These studies together with previous data showing that GnRH can overcome the abolition of lordosis by beta-endorphin in the MCG, indicate a close relationship between beta-endorphin (but not Met-enkephalin or dynorphin) and GnRH systems in the MCG in the control of lordosis behaviour. Thus, the inhibition of lordosis by CRF and the complete reversal of this blockade by naloxone or anti-beta-end-G may suggest that CRF could enhance the release of beta-endorphin from fibres in the MCG; beta-endorphin then inhibits lordosis by inhibiting the release of GnRH. However, a direct inhibitory effect of CRF on GnRH release is also likely since anti-CRF-gamma-globulin (anti-CRF-G) infused into the MCG produced a long-lasting facilitation of lordosis which can be blocked by an antagonist analogue of GnRH; in addition, previous studies have shown that GnRH infused into the MCG completely overcame the CRF-induced abolition of lordosis and potentiated lordosis to high levels. These results suggest that there may be functional neuroanatomical relationships between CRF, beta-endorphin and GnRH neuronal systems in the MCG in the control of female sexual behaviour. Neither Met-enkephalin nor dynorphin1-17 appear to participate in such mechanisms.

Animals↗
PubMed1985

Inhibition of the lordosis reflex in rats by intrahypothalamic infusion of neural excitatory agents: evidence that the hypothalamus contains separate inhibitory and facilitatory elements.

In attempts to activate lordosis-facilitating neural mechanisms in the ventromedial hypothalamus (VMH), neural excitatory agents were infused into the medial hypothalamus, and the effects of the infusions on the lordosis reflex and on the electrical activity of VMH neurons were studied. Surprisingly, bilateral intrahypothalamic infusion of glutamate (10 mM, 1.0 microliter/side) into behaving, ovariectomized, estrogen-treated rats displaying moderate lordotic responsiveness did not facilitate lordosis, but instead, resulted in a rapid (within a few minutes) and transient (recovery in about 20 min) inhibition of lordosis. Further experiments showed that this lordosis-inhibiting effect of glutamate was dose-related, and was completely blocked by prior infusion of a local anesthetic, procaine. Infusion of KC1 (1.5 or 15%, 1.0 microliter/side) also induced a dose-related, rapid and transient inhibition of lordosis, that was essentially identical to that induced by glutamate. Kainic acid (0.25 micrograms/0.5 microliter/side) also caused a rapid inhibition of lordosis, but the effect was long-lasting (days). The inhibition of lordosis by these agents was dissociated in time course, presence, and/or severity from effects on non-lordotic behaviors. Electrophysiological studies showed that all three agents tested could excite multiunit activity of the VMH, and that the time courses of these excitations were closely comparable to those of the inhibition of lordosis induced by the respective agents. Altogether, these studies indicated that the excitation of certain medial hypothalamic neurons can inhibit the lordosis reflex. The implied lordosis-inhibiting neural mechanisms are separate from facilitatory mechanism(s), according to differences in latency, duration, and procaine-sensitivity of response.

Animals↗