Facet Joints Of Lumbar Spine Research Articles

The relationship between structural changes in paraspinal muscles and intervertebral disc and facet joint degeneration in the lumbar spine of rats

BackgroundDegenerative spine disease is one of the largest causes of disability worldwide and has a multifactorial aetiology. Determining the leading causes of this multifactorial disease could help create new treatment approaches.PurposeStudy the impact of degenerative changes in the paraspinal muscles caused by local (prolonged compression) or systemic (high-fat diet) factors on the structure of the intervertebral discs (IVDs) and facet joints of the lumbar spine in rats.MethodsThe study was conducted using two animal models to create degenerative changes in the paraspinal muscles of 10 white laboratory rats for 90 days and five control rats: 1) high-fat diet model (model 1) involved keeping the rats on a high calorie diet; 2) compression model (model 2) involved binding the paraspinal muscles from L2 to S1 using non-absorbable sutures. Histological analysis for the facet joints and IVDs of rats (at the L1–L4 level) with semi-quantitative analysis of the structure conducted used by degeneration grading system for IVDs and cartilage degeneration score (OARSI) for facet joint.ResultsIn both models, 90 days after the experiment, the degenerative changes observed in the rats’ IVDs were more severe in the annulus fibrosus than in the nucleus pulposus. The height of the IVD in model 1 did not differ from the control group, but in the model 2 was 1.3 times greater (p < 0.001) compared with control. Degenerative changes in the IVD were scored out 5.3 ± 1.7 in model 1 and 5.32 ± 2.1 in model 2 of a possible 16. The height of the articular cartilage of the facet joints was smaller by 1.5 times (p < 0.001) and 1.4 times (p < 0.001) in model 1 and model 2, respectively, compared to the control. Degenerative changes of facet joint were scored out 3.7 ± 0.6 in model 1 and 3.8 ± 0.6 in model 2 of five points according to the cartilage degeneration score.ConclusionsIt was determined that rats who had structural changes in the lumbar paraspinal muscles as a result of being kept on a high-fat diet or subjected to prolonged compression for 90 days, showed degenerative changes in intervertebral discs and osteoarthritis in facet joints of lumbar spine.

The Root Causes of Lumbar Canal Stenosis: An Insight with a Narrative Review

In the older population, lumbar spinal stenosis is a frequent degenerative condition that can cause clinical symptoms such as neurogenic claudication or sciatica, either with or without low back pain. Anatomically, there are three different forms of lumbar spinal stenosis: central, foraminal, and lateral recess. The relationship between Ligamentum Flavum (LF) hypertrophy and mechanical stress, as seen in segmental instability or disc space expansion, and their correlation with lumbar facet joint arthropathy is still not clear. This review places particular emphasis on the causes like LF hypertrophy, lumbar segmental instability, lumbar segmental motion, disc degeneration, lumbar spine facet joint orientation, facet joint tropism and facet joint Osteoarthritis (OA) in Lumbar Canal Stenosis (LCS) studied in various different studies discovered in various other search databases. The present research will also help surgeons and radiologists to interpret neuroradiological data appropriately for surgery as well as non surgical treatment and get a better knowledge of the architecture of these structures and how they appear on neuroimaging investigations for further proper and apt management of LCS. Additionally, it would assist in creating a diagnostic algorithm for better functional results.

A novel technique for surgical excision of a symptomatic lumbar spine facet joint synovial cyst using a cyst dyeing method: a report of two cases and a literature review

The aim of this study was to investigate the efficacy of a cyst dyeing technique that was used during the surgical excision of facet joint cysts in 2 cases. We evaluated the patients’ clinical outcomes and perioperative complications after decompression of lumbar spinal stenosis caused by the cysts. Two patients, who underwent surgical decompression for symptomatic lumbar spinal stenosis caused by facet cysts in August and October 2020, were reviewed. Their main complaints were severe low back pain and sciatica 1 or 2 months ago, for which they visited Wooridul Spine Hospital, Daegu, Korea. Under general anesthesia, the cysts were removed with the cyst dyeing method, using indigo carmine. Clinical outcomes were assessed by preoperative and postoperative visual analog scale (VAS) scores. Perioperative complications were observed.Favorable clinical outcomes and no perioperative complications were reported. Low back pain and sciatica improved, as shown by changes of the VAS score from 9 or 8 to 1, and no dural defects were observed. The cyst dyeing method is an effective technique for the surgical removal of symptomatic lumbar spine facet joint cysts.

Lumbar spine abnormalities and facet joint angles in asymptomatic elite junior tennis players

BackgroundLumbar spine abnormalities, in particular stress fractures to the pars interarticularis, are common in elite junior tennis players, though the difference in prevalence between males and females remains unclear. Further, facet joint orientation appears to be a possible option for recognizing which players might go on to present with a pars stress fracture. Given the link between pars stress fractures and low back pain in tennis players, it appears logical to explore the link between facet joint angle and pars abnormalities. Thus, the purpose of this study was to describe the prevalence of lumbar spine abnormalities and explore the relationship between facet joint orientation and pars abnormalities in elite adolescent tennis players.MethodologyLumbar spine MRI images of 25 elite junior tennis players were obtained and distributed between five radiologists for analysis. Descriptive comparisons and confidence intervals were used to describe the prevalence of the abnormalities. A generalized linear regression model was conducted to investigate the relationship between lumbar pars abnormalities and lumbar facet joint angles.ResultsSixteen (64%) of 25 players were found to have at least one lumbar spine abnormality. Pars abnormalities affected 36% of players while bone marrow edema was found in 24% of players. Disc herniation, disc degeneration, and facet joint degeneration were diagnosed in 20%, 44%, and 24% of players respectively. Lastly, one player (4%) was diagnosed with spondylolisthesis. Females had significantly larger facet joint angles across L3/4 L5/S1 compared to males (p < 0.01). Further, those who had pars abnormalities had larger facet joint angles compared to those who did not (p < 0.001).ConclusionDisc degeneration, pars abnormalities, including bone marrow edema, and facet joint degeneration were common findings among elite adolescent tennis players.Additionally, this study is the first to discover that pars abnormalities are linked to facet joint angle in elite adolescent tennis players. This finding might assist in identifying tennis players at a greater risk of developing lumbar spine pars abnormalities in the future.

Correlation between Lumbar Spine Facet Joint Orientation and Intervertebral Disk Degeneration: A Positional MRI Analysis.

The contribution of facet joint orientation (FO) to degeneration of the functional units of the lumbar spine remains unclear. The study used positional magnetic resonance imaging (MRI) to evaluate the association between intervertebral disk degeneration and FO at the L3-L4 to L5-S1 spinal segments. This was a retrospective study of 450 outpatients admitted to the Spine Surgery Department of our hospital between January 2013 and January 2015 and with positional lumbar MRI data. Grade of intervertebral disk degeneration, FO relative to the midsagittal plane, vertebral translation (VT), and angular variation (AV) were assessed. No effect of baseline characteristics (age, sex, and body mass index) on intervertebral disk degeneration was observed. A significant difference in VT and AV was only present between grades 1 + 2 versus 4 at L5-S1 (both p = 0.005), and in FO only at L5-S1 between grades 1 + 2 versus 4 (p = 0.03) and grades 3 versus 4 (p = 0.04). AV and VT were correlated at all three lumbar segments (r = 0.224-0.309; p ≥ 0.01), with a correlation between FO and AV only at L3-L4 (r = 0.141; p = 0.035). Disk degeneration was associated with FO only at L5-S1. AV and VT of spinal segments of the mid to lower lumbar spine did not correlate with FO.

Association of chronic degenerative arthritis related chronic low back pain with altered lumbar facet joint orientation

ObjectiveTo examine the relationship between changes in lumbar spine facet joint (FJ) orientation and chronic low back pain (CLBP). MethodsWe retrospectively analyzed lumbar spine CT and MRI images of 98 patients referred for localized paraspinal CLBP and 98 age-and sex-matched asymptomatic individuals as controls. They were divided into four age groups (A, <40; B, 41–50; C, 51–60; D, 61–70; and E, 71–80 years old, respectively). FJ orientations were evaluated at the L3-4, L4-5, and L5-S1 lumbar levels. ResultsFJ angle showed a statistically significant more sagittal orientation in CLBP patients than in control groups in lower lumbar spine segments. The overall mean FJ angles in CLBP groups including all age groups combined at L3-4, L4-5, and L5-S1 levels were 32.33 ± 4.5, 36.11 ± 2.9, and 37.4 ± 6.1, degrees, respectively. The FJ angles in control group for all ages were 32.21 ± 3.7, 38.01 ± 4.6, and 40.18 ± 6.8°, respectively. The differences in FJ angle were statistically significant at both L4-5 and L5-S1 levels between the control and the CLBP groups (p < 0.01). The FJ orientation from upper lumbar spine to lumbar sacral junction demonstrated a gradual more coronal orientation transition in all subjects but this trend was significantly less in CLBP patients. The mean FJ angles for the control group at age groups A, B, C, D, and E were 33.52 ± 3.8, 35.7 ± 4.5, 38.25 ± 2.4, 35.49 ± 4.1, and 38.13 ± 5.8, respectively, while those in the CLBP groups were 35.63 ± 2.4, 35.26 ± 3.6, 35.99 ± 5.1, 35.3 ± 4.3, and 35.17 ± 6.7, respectively. ConclusionThere is a significant association between a more sagittal FJ orientation and facetogenic CLBP in lower lumbar vertebral levels. There is also age-dependent decrease in FJ orientation in sagittal plane at lower lumbar spinal levels in control as well as CLBP groups, however, this decrease in the CLBP groups was significantly more pronounced. Whether this change was an adaptive remodeling or alterations associated with chronic FJ osteoarthropathy should warrant further longitudinal studies.

Lumbar spine epidural abscess and facet joint septic arthritis due to Streptococcus agalactiae: a case report

BackgroundHere we report a rare case of lumbar spine epidural abscess and facet joint septic arthritis caused by Streptococcus agalactiae, which had spread to the iliopsoas muscles, leading to urine retention.Case presentationA 68-year-old woman with low back pain experienced a sudden onset of bilateral lower limb weakness, it was followed 14 days later by urine retention. At consultation, magnetic resonance imaging and identification of serum β-hemolytic streptococci provided a diagnosis of Streptococcus agalactiae infection. She was started on antibiotics. Despite diminishing signs of inflammation, preoperative MRI showed an epidural mass at T12-L4 compressing the cord and involving the paravertebral muscles as well. Group B beta-hemolytic streptococci were detected in both urine and blood. Because of bilateral lower limb weakness and urine retention, T12-L4 hemilaminectomy was performed. The L3/L4 intertransverse ligament resected and abscess drained. Histopathology revealed that inflammatory cells had invaded the facet joint. Group B beta-hemolytic streptococci were identified, confirming the diagnosis. The patient continued with the antibiotics postoperatively, and her health rapidly improved.ConclusionLumbar spine epidural abscess and facet joint septic arthritis caused by Streptococcus agalactiae is a clinical emergency, with significant morbidity and mortality especially with delayed diagnosis. A delay in both diagnosis and aggressive treatment can lead to not only severe neurological deficit but also to septicaemia, multiorgan failure, and even death.

Gouty Arthritis of the Axial Skeleton: A Case Report

We present a case of a patient with systemic gout disease who did not receive any treatments for 10 years. A seventy-one-year-old male came to our attention for physical weariness, chest discomfort, a mild fever for more than a month and right knee pain. His blood test and laboratory data showed elevated white blood cell (WBC), uric acid (UA) and C-reactive protein (CRP). The bone scintigraphy showed increased radioactive tracer suggestive of multiple arthritis including axial skeleton. Whole body computed tomography (CT) scan showed multiple areas of bone erosion and tophi, especially in the sternoclavicular joints, sternocostal joints and facet joints of lumbar spine. Gouty arthritis typically affects the peripheral joints of the appendicular skeleton, especially feet and hands. Systemic gout disease affects not only the peripheral joints of the appendicular skeleton, but also the axial skeleton. Although joint aspiration is needed to detect monosodium urate (MSU) crystals, both scintigraphy and CT scan are powerful means to diagnose gouty arthritis at the same time.

Facet Joint Orientation and Sagittal Spinopelvic Alignment in Patients with Degenerative Lumbar Scoliosis

The purpose of this study was to evaluate the association between lumbar spine facet joint orientation and tropism, sagittal spinopelvic alignment, and rotational deformity, identified by radiographic and computed tomography (CT) measurements, in degenerative lumbar scoliosis (DLS). Standing whole-spine sagittal radiographs and CT scans, including the pelvis, were performed and analyzed in 60 DLS patients (16 males, 44 females; mean age 65 years). Cobb angle, pelvic incidence (PI) and lumbar lordosis (LL) were measured on standing lumbar radiographs. Facet joint orientation on both sides at L3/4, L4/5, and L5/S1 was determined from transverse-plane CT. Facet joint tropism was defined as a difference in symmetry of more than 10 degrees between the orientations of the facet joints. There were significant differences in the incidence of facet joint tropism between the two groups at L3/4, L4/5, and L5/S1 (P = 0.011, P = 0.043, and P = 0.004, respectively). LL was significantly smaller in type II DLS (P = 0.049). Facet joint orientation, pelvic incidence, and Cobb angle did not differ between groups. No significant correlation between LL and PI was observed in either group. This study provides a reliability analysis of rotational deformity in patients with DLS. In conclusion, we observed a significant relationship between facet joint tropism and rotational deformity in patients with DLS. Furthermore, the different types of DLS demonstrated significant differences in LL that may induce spinal symptoms.

(18)F-Sodium Fluoride PET-CT Hybrid Imaging of the Lumbar Facet Joints: Tracer Uptake and Degree of Correlation to CT-graded Arthropathy.

We aim to evaluate 18F-NaF uptake by facet joints with hybrid PET-CT technique. Specifically, we evaluate NaF uptake in the facet joints of the lower lumbar spine, and correlate with the morphologic grade of facet arthropathy on CT. 30 consecutive patients who underwent standard vertex to toes NaF PET-CT for re-staging of primary neoplastic disease without measurable or documented bony metastases were identified. Maximum (SUVmax) and average (SUVavg) standardized uptake values were calculated for each L3-4, L4-5, and L5-S1 facet joint (n = 180) and normalized to average uptake in the non-diseased femur. A Pathria grade (0-3) was assigned to each facet based upon the CT morphology. Spearman's rank correlation was performed for normalized SUVmax and SUVavg with Pathria grade. ANOVA was performed with Tukey-Kramer pairwise tests to evaluate differences in uptake between Pathria groups. Facet normalized SUVmax (r = 0.31, P < 0.001) and SUVavg (r = 0.28, P < 0.001) demonstrated a mild positive correlation with CT Pathria grade. There was a wide range of uptake values within each Pathria grade subgroup with statistically significant differences in uptake only between Pathria grade 3 as compared to grades 0, 1, and 2. In conclusion, NaF uptake and morphologic changes of the facet joint on CT are weakly correlated. Physiologic information provided by NaF uptake is often discrepant with structural findings on CT suggesting NaF PET may supplement conventional structural imaging for identification of pain generating facet joints. Prospective investigation into the relationship of facet joint NaF uptake with pain and response to pain interventions is warranted.

(496) Percutaneous rupture and aspiration of lumbar intra-facet cysts: a case report

Synovial cysts arising from the lumbar spine facet joints are most commonly seen in the setting of degenerative spondylosis. These cysts are often termed juxta-facet cysts since they are located beside the facet joint and only exhibit a communicating pathway with the joint itself. There may be a small amount of fluid within the facet joint but the majority of the fluid lies within the cyst. Treatment options include surgical resection and percutaneous rupture. Percutaneous rupture of lumbar facet cysts is most commonly performed indirectly through the facet joint by use of CT guidance or fluoroscopy. We present a unique case that describes the percutaneous rupture and aspiration of lumbar facet cysts located entirely in the joint itself (intra-facet cysts) using fluoroscopy. A 52-year-old female presented with a one-year history of axial low back pain worse when lying down. The pain radiated to her bilateral buttocks but she denied parasthesias. She had already tried oral anti-inflammatory medications, physical therapy, and opioid medications with no improvement in her pain. Lumbar spine MRI revealed large bilateral intra-facet cysts at L4-L5 with a grade 2 spondylolisthesis at L4-L5. The patient was seen by a spine surgeon who recommended conservative treatment with no surgical intervention at that time. After surgical consultation, the decisionwasmade to perform percutaneous rupture and aspiration of the bilateral intra-facet cysts at L4-L5 followed by intra-articular facet steroid injections under fluoroscopy. One milliliter of synovial fluid was aspirated from each of her facet joints using a 22-guage needle with no complications. Following the procedure, the patient reported an 80% decrease in her pain score. Although juxta-facet cysts are the most common presentation of lumbar spine synovial cysts, intra-facet cysts may also occur and can be successfully treated with percutaenous rupture and aspiration under fluoroscopy.

Influence of lumbar curvature and rotation on forward flexibility in idiopathic scoliosis.

Lumbar spine facet joints are arranged sagittally and mainly provide forward flexibility. Rotation of the lumbar vertebral body and coronal plane deformity may influence the function of lumbar forward flexibility. We hypothesize that the more advanced axial and coronal plane deformity could cause more limitation on forward flexibility in patients with idiopathic scoliosis. Between January 2011 and August 2011, 85 patients with adolescent idiopathic scoliosis were enrolled in this study. The proximal thoracic, major thoracic, thoracolumbar/lumbar (TL/L), and lumbar (L1/L5) curves were measured by Cobb's method. Lumbar apical rotation was graded using the Nash-Moe score. Lumbar forward flexibility was measured using the sit and reach (S and R) test. Statistical analysis was performed using one-way analysis of variance (ANOVA), Spearman's and Pearson's correlation coefficients. The mean age was 16.1 ± 2.84 years. The mean proximal thoracic, major thoracic, TL/L, and L1/L5 curves were 17.61° ± 8.92, 25.56° ± 11.61, 26.09° ± 8.6, and 15.10° ± 7.85, respectively. The mean S and R measurement was 25.56 ± 12.33 cm. The magnitude of the TL/L and L1/L5 curves was statistically positively related to vertebral rotation (r(s) = 0.580 and 0.649, respectively). The correlation between the S and R test and both the TL/L and L1/L5 curves was negative (r(p) = -0.371 and -0.595, respectively). Besides, the S and R test also demonstrated a significant negative relationship with vertebral rotation (rs = -0.768). In patients with idiopathic scoliosis, spinal deformity can diminish lumbar forward flexibility. Higher lumbar curvature and rotation lead to greater restriction of lumbar flexion.

The prevalence of lumbar spine facet joint osteoarthritis and its association with low back pain in selected Korean populations.

BackgroundThis study was to evaluate the association of lumbar spine facet joint osteoarthritis (LSFJOA) identified by multi-detector computed tomography (MDCT) with age and low back pain (LBP) in an adult community-based population in Korea.MethodsA sample of 472 participants (age range, 20 to 84 years) who underwent MDCT imaging for abdominal or urological lesions, not for chief complaints of LBP, were included in this study. LSFJOA based on MDCT findings was characterized using four grades of osteoarthritis of the facet joints. The prevalence of LSFJOA according to age group (below 40 years, 40-49 years, 50-59 years, 60-69 years, and above 70 years), gender, and spinal level was analyzed using chi-square tests and the association between LBP and LSFJOA adjusting for age, gender, and spine level was analyzed using multiple binary logistic regression test.ResultsEighty-three study subjects (17.58%) had LSFJOA (grade ≥ 2). The prevalence of LSFJOA was not associated with gender (p = 0.092). The prevalence of LSFJOA increased with age (p = 0.015). The highest prevalence of LSFJOA was observed at L4-5 in men (p = 0.001) and at L5-S1 in women (p = 0.003), and at L5-S1 in the overall population (p = 0.000). LSFJOA was not associated with LBP in men (p = 0.093) but was associated with LBP in women (p = 0.003), especially at L3-4 (p = 0.018) and L5-S1 (p = 0.026).ConclusionsThe prevalence of LSFJOA based on the computed tomography imaging was 17.58% in the adult community Korean population. The prevalence of LSFJOA increased with age, and the highest prevalence was noted at L5-S1. LSFJOA was not associated with LBP at any spinal level and age except at L3-4 and L5-S1 in women.

The Relationship Between Lumbar Spine Facet Joint Arthritis and Dynamic and Static Low Back Pain. Which Level of Lumbar Spine Facet Joint Arthritis is Most Influenced on the Static or Dynamic Low Back Pain?

The Relationship Between Lumbar Spine Facet Joint Arthritis and Dynamic and Static Low Back Pain. Which Level of Lumbar Spine Facet Joint Arthritis is Most Influenced on the Static or Dynamic Low Back Pain?

AB1400 Physiotherapy in the recovery of quality of life in patients with acute lumbar facet

BackgroundPain in the lumbar spine is present on at least 65% of patients that addresses a rehabilitation service.ObjectivesThe objective of this study was to assess the recovery of back pain...

Desmoid Type Fibromatosis in the Facet Joint of Lumbar Spine: Case Report and Review of Literature

Desmoid type fibromatosis is a benign fibroblastic tumor arising from the fascia or musculoaponeurosis. It may occur in various locations, but most commonly in the shoulder girdle and neck; to our knowledge, there has been no reported case originating from a facet joint of the spine. We report CT and MR imaging findings of a desmoid type fibromatosis, involving the facet joint of the L3-4 spine with bone involvement.

Three-dimensional movements of the lumbar spine facet joints and segmental movements: in vivo examinations of normal subjects with a new non-invasive method

Examination with CT and image registration is a new technique that we have previously used to assess 3D segmental motions in the lumbar spine in a phantom. Current multi-slice computed tomography (CT) offers highly accurate spatial volume resolution without significant distortion and modern CT scanners makes it possible to reduce the radiation dose to the patients. Our aim was to assess segmental movement in the lumbar spine with the aforementioned method in healthy subjects and also to determine rotation accuracy on phantom vertebrae. The subjects were examined in flexion-extension using low dose CT. Eleven healthy, asymptomatic subjects participated in the current study. The subjects were placed on a custom made jig which could provoke the lumbar spine into flexion or extension. CT examination in flexion and extension was performed. The image analysis was performed using a 3D volume fusion tool, registering one of the vertebrae, and then measuring Euler angles and distances in the registered volumes. The mean 3D facet joint translation at L4-L5 was in the right facet joint 6.1mm (3.1-8.3), left facet joint 6.9mm (4.9-9.9), at L5-S1: right facet joint 4.5mm (1.4-6.9), and for the left facet joint 4.8mm (2.0-7.7). In subjects the mean angles at the L4-L5 level were: in the sagittal plane 14.3°, coronal plane 0.9° (-0.6 to 2.8), and in the transverse plane 0.6° (-0.4 to 1.5), in the L5-S1 level the rotation was in sagittal plane 10.2° (2.4-16.1), coronal plane 0° (-1.2 to 1.2), and in the transverse plane 0.2° (-0.7 to 0.3). Repeated analysis for 3D facet joint movement was on average 5mm with a standard error of mean of 0.6mm and repeatability of 1.8mm (CI 95%). For segmental rotation in the sagittal plane the mean rotation was 11.5° and standard error of mean 1°. The repeatability for rotation was 2.8° (CI 95%). The accuracy for rotation in the phantom was in the sagittal plane 0.7°, coronal plane 1°, and 0.7 in the transverse plane. This method to assess movement in the lumbar spine is a truly 3D method with a high precision giving both visual and numerical output. We believe that this method for measuring spine movement is useful both in research and in clinical settings.

Development of a versatile intra-articular pressure sensing array

A new sensor array intended to accurately and directly measure spatial and time-dependent pressures within a highly curved biological intra-articular joint was developed and tested. To evaluate performance of the new sensor array for application within intra-articular joints generally, and specifically to fit within the relatively restrictive space of the lumbar spine facet joint, geometric constraints of length, width, thickness and sensor spatial resolution were evaluated. Additionally, the effects of sensor array curvature, frequency response, linearity, drift, hysteresis, repeatability, and total system cost were assessed. The new sensor array was approximately 0.6 mm in thickness, scalable to below the nominal 12 mm wide by 15 high lumbar spine facet joint size, offered no inherent limitations on the number or spacing of the sensors with less than 1.7% cross talk with sensor immediately adjacent to one another. No difference was observed in sensor performance down to a radius of curvature of 7 mm and a 0.66 ± 0.97% change in sensor sensitivity was observed at a radius of 5.5 mm. The sensor array had less than 0.07 dB signal loss up to 5.5 Hz, linearity was 0.58 ± 0.13% full scale (FS), drift was less than 0.2% FS at 250 s and less than 0.6% FS at 700 s, hysteresis was 0.78 ± 0.18%. Repeatability was excellent with a coefficient of variation less than 2% at pressures between 0 and 1.000 MPa. Total system cost was relatively small as standard commercially available data acquisition systems could be utilized, with no specialized software, and individual sensors within an array can be replaced as needed. The new sensor array had small and scalable geometry and very acceptable intrinsic performance including minimal to no alteration in performance at physiologically relevant ranges of joint curvature.

Vascular disease is associated with facet joint osteoarthritis

Epidemiologic studies have demonstrated associations between vascular disease and spinal degeneration. We sought to examine whether vascular disease was associated with lumbar spine facet joint osteoarthritis (FJ OA) in a community-based population. 441 participants from the Framingham Heart Study multi-detector computed tomography (MDCT) Study were included in this ancillary study. We used a quantitative summary measure of abdominal aortic calcification (AAC) from the parent study as a marker for vascular disease. AAC was categorized into tertiles of 'no' (reference), 'low', and 'high' calcification. FJ OA was evaluated on computerised tomography (CT) scans using a four-grade scale. For analytic purposes, FJ OA was dichotomized as moderate FJ OA of at least one joint from L2-S1 vs no moderate FJ OA. We examined the association of AAC and FJ OA using logistic regression before and after adjusting for age, sex and body mass index (BMI). Furthermore, we examined the independent effect of AAC on FJ OA after including the known cardiovascular risk factors; diabetes, hypertension, hypercholesterolemia, and smoking. Low AAC (OR 3.84 [2.33-6.34]; P<or=0.0001) and high AAC (9.84 [5.29-18.3]; <or=0.0001) were strongly associated with FJ OA, compared with the reference group. After adjusting for age, sex, and BMI, the association with FJ OA was attenuated for both low AAC (1.81 [1.01-3.27]; P=0.05) and high AAC (2.63 [0.99-5.23]; P=0.05). BMI and age were independently and significantly associated with FJ OA. The addition of cardiovascular risk factors to the model did not substantially change parameter estimates for either AAC tertile. AACs were associated with FJ OA in this community-based population, when adjusting for epidemiologic factors associated with spinal degeneration, and cardiovascular risk factors. Potentially modifiable risk factors for facet degeneration unrelated to conventional biomechanical paradigms may exist. This study is limited by cross-sectional design; longitudinal studies are needed.

Facet Orientation and Tropism

Cross-sectional study. To evaluate the association between lumbar spine facet joint orientation, facet joint tropism, and spondylolysis identified by multidetector computed tomography (CT) in the community-based Framingham Heart Study. The association between lumbar spondylolysis and facet orientation and tropism remains unclear. This study was an ancillary project to the Framingham Heart Study. Three thousand five hundred twenty-nine participants of the Framingham Heart Study aged 40 to 80 years underwent multidetector CT imaging to assess aortic calcification. One hundred ninety-one subjects were included in this ancillary study. Facet joint features and spondylolysis were evaluated on CT scans. The final analyzed sample included 104 men with mean age 51.90+/-11.25 years and 84 women with mean age 53.61+/-10.20 years. The association between spondylolysis and facet orientation and tropism was examined using univariate and multivariate analyses. Spondylolysis was prevalent in 11.5% of the total population. chi2 test demonstrated a significant sex difference in prevalence of spondylolysis (P=0.0154), with almost 3 times higher prevalence among men. There was no statistically significant difference in facet orientation and continuous facet tropism between individuals with and without spondylolysis at the L5 level (P=0.49 to 0.91). After adjustment for age, sex, and body mass index, no significant association between the occurrence of spondylolysis and facet orientation and tropism was found. In the studied sample the prevalence of facet joint osteoarthritis was significantly higher in individuals with spondylolysis than in those without spondylolysis at both sides of L4-L5 spinal level (P=0.044 at the right side and P=0.003 at the left side) and at left side of L5-S1 level (P=0.038). We did not find an association between facet orientation, facet tropism, and spondylolysis. One of the possible explanations for this is that the high prevalence of facet joint osteoarthritis in individuals with spondylolysis in the studied sample might have led to diminished differences in facet orientation.