Bilateral Spondylolysis Research Articles

Compression Myelopathy due to Proliferative Changes around C2 Pars Defects without Instability.

We report a case with compression myelopathy due to proliferative changes around the C2 pars defects without instability. A 69-year-old man presented with progressive clumsy hands and spastic gait. Plain radiographs showed bilateral spondylolysis (pars defects) at C2 and fusion between C2 and C3 spinous processes. Dynamic views revealed mobility through the pars defects, but there was no apparent instability. Computed tomography showed proliferative changes at the pars defects, which protruded into spinal canal. On magnetic resonance imaging, the spinal cord was compressed and intramedullary high signal change was found. A diagnosis of compression myelopathy due to proliferative changes around the C2 pars defects was made. We performed posterior decompression. Postoperatively, symptoms have been alleviated and images revealed sufficient decompression and no apparent instability. In patients with the cervical spondylolysis, myelopathy caused by instability or slippage have been periodically reported. The present case involving C2 spondylolysis is extremely rare.

Rare Bilateral C3 Cervical Spondylolysis: Report of Four Cases and a Literature Review

Objective To review and discuss the etiology, diagnosis and treatment C3 of bilateral cervical spondylolysis. Methods This was a retrospective review of the clinical features, imaginge findings, and treatment of 4 cases of bilateral C3 cervical spondylolysis, with a review of the literature. Results A 21-year-old woman, a 26-year-old man, a 14-year-old boy, and a 46-year-old man were diagnosed with bilateral C3 cervical spondylolysis. The patients had characteristic bilateral clefts between the articular pillar and the facets of C3, as well as spina bifida on CT. Although spondylolisthesis was not observed, spinal cord compression was definitive. All patients underwent posterior decompression with satisfactory results. Conclusions C3 cervical spondylolysis is rare condition. The cause is most likely congenital. Diagnosis is dependent on characteristic radiological features. Surgical treatment is the first choice.

Spondylolysis and Spina Bifida Occulta in Pediatric Patients: Prevalence Study using Computed Tomography as a Screening Tool

Introduction The prevalence of spondylolysis reported from radiograph-based studies has been questioned in the recent computed tomography (CT)–based studies in adults; however, no new data are available in pediatric patients. Spina bifida occulta (SBO), which has been associated to spondylolysis, may be increasing its prevalence, according to the recent studies in adults in the last decades, but without new data in pediatric patients. We aimed to determine the prevalence of spondylolysis and SBO in pediatric patients using abdomen and pelvis CT as a screening tool. Patients and Methods We studied 228 patients, 4 to 15 years' old (107 males), who were evaluated with abdomen and pelvis CT scans for reasons not related to the spine. The entire lumbosacral spine was evaluated to detect the presence of spondylolysis and SBO. We compared the prevalence of spondylolysis in patients with and without SBO. A logistic regression analysis was performed to determine the effect of age and sex as independent predictors of spondylolysis and SBO. Results The mean age of all study patients was 11.2 ± 2.7 years. A total of 107 patients were males (46.9%) and 121 were females (53.1%). The prevalence of lumbar spondylolysis was 3.5%, 95% CI: 1.1 to 5.9% (eight patients). Spondylolysis was observed at L5 in seven patients and at L4 in one; seven patients exhibited bilateral spondylolysis, while one patient had a unilateral pars defect. Among the patients with spondylolysis, two exhibited olisthesis (0.9% of the sample), both corresponding to grade I slip. Males exhibited a 4.7% (95% CI: 0.6–8.7) prevalence of spondylolysis (five patients) compared with a 2.5% (95% CI: 0.3–5.3) prevalence in females (three patients), p = 0.48. The prevalence of SBO was 41.2%, 95% CI: 34.8–59.2% (94 patients). Overall, 6 patients had SBO at L5 (6.4%), 80 patients at S1 (85.1%), and 8 patients at S2 (8.5%). SBO was found in 51.4% of males (95% CI: 41.8–61) and in 32.2% of females (95% CI: 23.8–40.7), p < 0.01. The prevalence of SBO decreased with increasing age. The prevalence of spondylolysis was 5.3% in the patients with SBO and 2.2% in patients without SBO, p = 0.28. Logistic regression analysis revealed that male sex (OR = 2.1, 95% CI: 1.2–3.7; p < 0.01) and age (OR = 0.8, 95% CI: 0.7–0.9; p < 0.01) were significantly related to the presence of SBO. Conversely, neither sex (OR = 2, 95% CI: 0.5–8.5; p = 0.32) nor age (OR = 1, 95% CI: 0.8–1.4; p = 0.78) were significantly related to the presence of spondylolysis. Conclusion This is the first study using CT as a screening method to evaluate the prevalence of spondylolysis and SBO in a pediatric population. We found a 3.5% prevalence of lumbar spondylolysis and a 41.2% prevalence of SBO in this cohort. Most patients with spondylolysis had a pars defect at L5. We also demonstrated that SBO was independently influenced by male and younger age.

The effectiveness of surgical versus conservative treatment for symptomatic unilateral spondylolysis of the lumbar spine in athletes: a systematic review.

Spondylolysis is a common cause of low back pain in athletes. Historically, spondylolysis injuries were thought to be mostly bilateral; however advances in lumbar spine imaging have shown that in certain athlete groups, unilateral spondylolysis is highly prevalent. It remains unclear whether athletes with unilateral spondylolysis who undergo surgical repair are able to return to sports as effectively or faster than if they had conservative treatment. To determine the effectiveness of surgical fixation performed after a trial period of conservative management, compared to the effectiveness of conservative management only for unilateral spondylolysis in athletes. Athletes with symptomatic unilateral spondylolysis of the lumbar spine. Types of intervention(s): Surgical interventions which attempted a direct repair of the pars interarticularis, compared to conservative management. Types of studies: Experimental and epidemiological study designs were considered for inclusion. The majority of the studies reviewed consisted of descriptive epidemiological study designs including case series, individual case reports and descriptive cross sectional studies. Types of outcomes: The primary outcome of interest in this review was the ability to return to sport. The effectiveness of surgery on pain and overall function were secondary outcomes of interest. A three-step search strategy that aimed to find both published and unpublished studies was utilized. The search was limited to studies published in the English language between 1 January 1970 and 1 September 2013. The studies were critically appraised using one of the standardized critical appraisal instruments from The Joanna Briggs Institute. Details describing each study and results on effectiveness in promoting the outcomes of interest were extracted from papers included in the review using the standardized data extraction tool from The Joanna Briggs Institute. Due to heterogeneity in the included studies, the results for similar outcome measures were not pooled in statistical meta-analysis. A narrative and tabular format was used to synthesize the results of identified and included studies. Five studies reporting results for the outcomes of interest were critically appraised and included in the review. One study was a quasi-experimental design, while the other four were case series studies. Due to the paucity of data, studies were included regardless of whether their participants were exclusively athletes with unilateral spondylolysis or adults (athletes and non-athletes) with unilateral and bilateral spondylolysis. Sub-group analysis was used to distinguish the findings for the main participant group of interest, namely athletes with unilateral spondylolysis. The limited evidence on the effectiveness of surgical treatment versus conservative treatment for unilateral spondylolysis in athletes does not allow any conclusions to be drawn about the relative effectiveness of surgery versus conservative treatment for facilitating rapid return to sport or a high level of post injury sporting level/performance. It does suggest, however, that for adult athletes for whom conservative treatment has not been successful, surgery is likely to enable return to sport, reduce pain and promote overall function.

Unilateral pedicle stress fracture in a long-term hemodialysis patient with isthmic spondylolisthesis.

Most unilateral pedicle stress fractures occur on the contralateral side of patients with unilateral spondylolysis. However, there are few reports of unilateral pedicle stress fractures in patients with bilateral spondylolysis and spondylolisthesis. We report a unique case of unilateral pedicle stress fracture in a long-term hemodialysis patient with isthmic spondylolisthesis. A 65-year-old man who had undergone hemodialysis presented with lower back pain that had persisted for several years. The patient experienced severe right lower extremity pain with no history of trauma. Computed tomography revealed unilateral pedicle fracture with bilateral L5 spondylolysis and spondylolisthesis with progression of scoliosis. The patient underwent Gill laminectomy of L5 with pedicle screw fixation at L4-S1 and interbody fusion at L5-S1. The patient's leg pain ceased immediately, and he began walking without leg pain. In our present patient, development of scoliosis caused by destructive spondyloarthropathy may have contributed to a unilateral pedicle fracture.

Rare bilateral C3 cervical spondylolysis:Report of four cases and a literature review

ObjectiveTo review and discuss the etiology, diagnosis and treatment C3 of bilateral cervical spondylolysis.MethodsThis was a retrospective review of the clinical features, imaginge findings, and t...

Direct Repair for Treatment of Lumbar Symptomatic Spondylolysis without Spondylolisthesis in Young Patients Using Gillet Technique (V-Shaped Rod)

Introduction Spondylolysis developed during individual growth. In this article, direct repair of the pars defect was used to treat lumbar symptomatic spondylolysis without spondylolisthesis in young patients. Indication and postoperative outcomes of this operation were analyzed, to investigate the method of early treatment of spondylolysis, which can avoid the complication of spinal fusion for delayed isthmic spondylolisthesis caused by spondylolysis. Materials and Methods Twelve cases of lumbar symptomatic spondylolysis were retrospectively reviewed; all the cases received direct repair for the pars defect during 2005 to 2011, and was followed up for at least 2 years. Among them, there are eight cases of male and four cases of female, average 24.5 years old; there are 10 L5 spondylolysis and 4 L4 spondylolysis. They have low back pain and X-ray-confirmed bilateral spondylolysis without spondylolisthesis. There was no disc degeneration on MRI. The operation includes pars debridement, pedicle screw insertion, V-shaped rod connection, and bone autograft. VAS score was used to evaluate the pain status of the patient. Results All the patients got symptoms relieved, VAS score was reduced from 4.8 preoperation to 2.3 postoperation, and they all resumed to original work. During follow-up, the pars defect attained bony union in X-ray and 3D CT scan. Conclusion For the developmental spondylolysis with severe local symptom, but no disc degeneration, direct repair for the pars defect with pedicle screw and V-shaped rod and bone autograft can be used to heal the pars defect. This treatment, which is safe and effective, can reduce occurrence of disc degeneration caused by lumbar instability and delayed spondylolisthesis, avoid complications caused by spinal fusion. Disclosure of Interest None declared

Study on dual-source and image reconstruction technique application in lumbar spondyloschisis without sliding

Objective To explore the technical advantages and clinical value of dual-source and image reconstruction technique application in lumbar spondyloschisis without sliding. Methods 36 cases of patients with LSWS were collected who were examined by dual-source CT scan and diagnosed definitely. 18 cases of patients were examined by X-ray （ including lumbar vertebrae and double oblique）. The diagnosis rate of X-ray and CT scanning in diagnosing LSWS were calculated, which was made statistical analysis. The image of 36 cases patients with LSWS were reconstructed by multi-planar reconstruction（MPR） ,volume rendering technique（VR）and curved planar reconstruction（CPR）. The display rate was calculated, which was made statistical analysis according to various image reconstruction in diagnosing I_SWS. Results 7 cases of patients with LSWS were found by X-ray examination. 36 cases of patients with LSWS were found by dual-source CT examination. The display rate was 38.9% and 100.0%. 71 LSWS were found in 36 cases of patients with LSWS ,35 cases were bilateral spondylolysis, 1 case was unilateral spondylolysis. In several image reconstruction methods, CPR and cutting VR showed the highest rate in diagnosing LSWS, which was 100.0%. The symptom of LSWS in X-ray examination：local thinning and structural disorder in lumbar spondylol- ysis, cortical discontinuity. The symptom of LSWS in CT examination were as follows ： clear linear low density shadow in lumbar,ends hardening and bone fragments in some case. Conclusion The dual-source CT and its image recon- struction technology have the technological superiority and higher clinical value in diagnosing LSWS,which is crucial to prevent LSWS misdiagnosed, and could become the preferred examination in screening and diagnosing LSWS. Key words: Lumbar Spondylolysis Without Sliding; Dual-source CT; Image Processing, Computer - Assisted

Congenital Absence of the Lumbar Facet Joint Associated With Bilateral Spondylolysis of the Fifth Lumbar Vertebra

A 14-year-old boy presented with a rare case of congenital absence of lumbar facet joint manifesting as low back pain. Physical examination showed no neurological or hematologic abnormalities. Radiography revealed absence of a facet joint on the right side of L4-5. Computed tomography and three-dimensional computed tomography revealed absence of the facet joint on the right side of L4-5 and spondylolysis on both sides of L5. Pain subsided after conservative treatment. This is an extremely rare case of congenital absence of lumbar facet joint associated with bilateral spondylolysis.

Lumbar Spondylolysis in Juveniles from the Same Family: A Report of Three Cases and a Review of the Literature

Spondylolysis is reported as a stress fracture of the pars interarticularis with a strong hereditary basis. Three cases of lumbar spondylolysis in juveniles from the same family are reported, and the genetics of the condition are reviewed. The first boy, a 13-year-old soccer player, was diagnosed with terminal stage L5 bilateral spondylolysis with grade 1 slippage. The second boy, a 10-year-old baseball player, had terminal stage right side unilateral spondylolysis. The third boy, also a 10-year-old baseball player, was diagnosed with early stage bilateral L5 spondylolysis. The second and third boys are identical twins, and all three cases exhibited concomitant spina bifida occulta. Lumbar spondylolysis has a strong hereditary basis and is reported to be an autosomal dominant condition.

Diagnosis of spondylolysis on MRI: Importance of recognition of hypoplastic L5 on MRI

ObjectiveTo perform a combined (retrospective and prospective) study to further characterize hypoplastic L5, its correlation with spondylolysis and other associated abnormalities on routine Computed tomography and magnetic resonance imaging. MethodsWe studied the Computed tomography and magnetic resonance imaging images of 29 patients with hypoplasia and posterior wedging of L5 with bilateral spondylolysis at L5. These cases were followed up retrospectively and prospectively. The anteroposterior diameter of L4, L5 and S1 was calculated and compared. The percentage of posterior wedging of L5 was calculated. Anterolisthesis, hypoplastic pedicle, facet joints, L4–5 and L5–S1 intervertebral discs, nerve roots and fragmentation of pars interarticularis were also studied. ResultsThe mean difference of anteroposterior diameter between L4 and L5 was 2.75mm and of L5 and S1 was 3.78mm. The mean percentage of posterior wedging was 31%. Grade I anterolisthesis was present in 13 patients and grade II in 2 patients. Facet joint arthropathy was seen in 20 patients. In 24 patients, there was hypoplastic pedicle. Pars fragmentation was seen in 7 patients. L5–S1 disc disease was seen in 21 patients out of whom 8 had exiting nerve root compression. L4–L5 disc disease was seen in 10 patients of whom 5 had exiting nerve root compression. ConclusionsHypoplastic L5 is a strong predictor of bilateral spondylolysis even in the absence of true anterior slippage. True anterior slippage and disproportionate adjacent disc disease result in varying degrees of exiting nerve root compression. Advances in knowledgeL5 hypoplasia can simulate anterolisthesis and can predict the bilateral spondylolysis. L5 hypoplasia can lead to early disc disease.

Botulism-like syndrome or widespread diffusion syndrome after injection of botulinum toxin A for neurogenic detrusor overactivity

.– A 27-year-old patient, with PKAN heredodegenerative dystonia,has truncal dystonia symptomatology. Suddenly, she complained of low-backpainevaluatedat10/10onaverbalscale.Low-backpainisinducedbyrepetitivedystonic movements with upper limbs anterior elevation, spinal and hipextension (opisthotonos). Radiographs showed a L3 bilateral spondylolysis notshown in the previous radiographs. A classical corset immobilization isn’tpossible because of movement disorders. A first botulinum toxin injection isperformed (150 UI Botox

Pneumothorax after botulinum toxin type A

literature. Case report.– A 27-year-old patient, with PKAN heredodegenerative dystonia, has truncal dystonia symptomatology. Suddenly, she complained of low-back pain evaluated at 10/10 on a verbal scale. Low-back pain is induced by repetitive dystonic movements with upper limbs anterior elevation, spinal and hip extension (opisthotonos). Radiographs showed a L3 bilateral spondylolysis not shown in the previous radiographs. A classical corset immobilization isn’t possible because of movement disorders. A first botulinum toxin injection is performed (150 UI Botox) in lumbar paraspinal muscles for pain relief. Anterior head of deltoideus and gluteus maximus are also injected (for a total dose of 400 UI Botox each session) to break the extension scheme. Four weeks after injections, the pain is evaluated at 5/10 and movement disorders were less frequent. Thanks to the adapted wheelchair and the posterior articulars infiltration bilaterally (125 mg of hydrocortancyl), the patient is totally relieved. Because of pain recurrence, toxin injections are effectively renewed each 3 months. Discussion.– The increase of spondylolysis frequency is shown in CP patients [1], one of the most frequent pathology with dystonia. The effectiveness of botulinum toxin injections in spinal muscles to decrease contractions is hard to prove but some articles agree with a decrease of disorderedmovements and pain [2].

Isolated unilateral vertebral pedicle fracture caused by a back massage in an elderly patient: a case report and literature review

The vertebral pedicle injuries are clinically common. However, the isolated vertebral pedicle fracture with intact vertebral bodies is a rare lesion. We reported a case of a 66-year-old man who experienced a pedicle fracture after a back massage. The patient sustained osteoporosis, long-existing low back pain and nerve compression symptoms without antecedent major trauma. Imaging findings demonstrated an isolated unilateral L5 vertebral pedicle fracture with intact vertebral bodies, spinal canal stenosis at the L4-5 levels, bulging annulus fibrosus at the L4-S1 levels, bilateral spondylolysis and an L5/S1 spondylolisthesis. The patient underwent L4-S1 decompressive laminectomy, L5/S1 discectomy and neurolysis, and reduction and fixation of the L5 vertebral pedicle fracture and L5/S1 spondylolisthesis using the pedicle nail system. At follow-ups, the patient showed good recovery without pain or numbness in the low back and bilateral lower extremities. This study raises the awareness of a complication of alternative medicine and the possibility of a pedicle fracture caused by a low-energy trauma.

CT volumetry of lumbar vertebral bodies in patients with hypoplasia L5 and bilateral spondylolysis and in normal controls

To examine the feasibility and results of calculating the volume of lumbar vertebral bodies in normal patients and patients with suspected hypoplasia of L5. Lumbar multi-detector CT was performed in 38 patients with bilateral spondylolysis and hypoplasia of L5 and in 38 normal patients. Lumbar vertebral body volume of L3, L4 and L5 was measured by CT volumetry with a semi-automated program, created with MeVisLab. In the control group, the average vertebral body volume (in cubic centimeters) of L3 was 35.93 (±7.33), 36.34 (±7.13) for L4 and 34.63 (±6.88) for L5. In patients with suspected hypoplasia L5 the average body volume (in cubic centimeters) of L3 was 36.85 (±7.37), 36.90 (±6.99) for L4 and 33.14 (±6.57) for L5. The difference in mean vertebral body volume for L3, L4 and L5 between both groups was statistically not significant. However, there was a statistically significant difference of the ratio L5/L4 (P < 0.001) between both groups: the mean ratio L5/L4 in the control group was 95.3 ± 3.9%, the ratio for the hypoplastic L5 group was 89.9 ± 6.3%. There was no significant difference in the vertebral body volume for L3, L4 and L5 between both groups due to inter-patient variability. However, the relation between the body volume of L5 and L4 is significantly different between both groups. The volume of the vertebral body of L5 proved to be on average 10.2% smaller than the volume of L4 in the group with hypoplasia L5 versus 4.7% in the control group.

Correlation of Sacropelvic Geometry With Disc Degeneration in Spondylolytic Cadaver Specimens

An anatomic study of sacral inclination, pelvic incidence, pelvic lordosis, and disc degeneration in cadaveric lumbar spines. To evaluate the relationship between sacropelvic parameters and disc degeneration in subjects with bilateral spondylolysis at L5. L5-S1 disc degeneration is greater in patients with spondylolytic defects (L5-S1) than with an intact pars interarticularis secondary to the instability caused by spondylolysis. Sacral inclination, pelvic incidence, and pelvic lordosis affect sagittal balance and axial forces on the L5-S1 disc. An observational study was performed on 120 cadaveric specimens with spondylolysis (L5-S1) identified of 3100 total cadaveric specimens. Nine specimens were excluded because of incomplete or degraded skeletal elements; 10 were excluded for having unilateral defects only. The specimens were evaluated for sacral inclination, pelvic incidence, and pelvic lordosis. Disc degeneration and facet arthrosis at L4-L5 and L5-S1 were measured by the classification of Eubanks et al. Linear regression analyses were then used to determine the relationship between sacropelvic parameters and degeneration at the L5-S1 segment, correcting for confounding factors such as age, sex, and race. Linear regression demonstrated a significant association between sacral inclination and disc degeneration at L5-S1 (P = 0.018). Specimens were then divided into two groups, those in the highest quarter of pelvic incidence, and the remainder. Spearman rank correlation demonstrated a significant association between disc degeneration at L5-S1 and the highest quarter of pelvic incidence (P = 0.017). Increasing pelvic lordosis was also associated with an increase in facet arthrosis at L4-L5 (P = 0.006). The findings of this study show a relationship between the sacropelvic geometry and the degree of L5-S1 disc degeneration as well as L4-L5 facet degeneration in spondylolytic specimens. This relationship may prove useful in predicting the course of disc degeneration in patients with spondylolysis.

Lumbar shape characterization of the neural arch and vertebral body in spondylolysis: A comparative skeletal study

The lumbar vertebral shape is an important causative factor in spondylolysis (SP). However, a complete characterization of this shape, that would shed light on its pathophysiology enhance its earlier diagnosis, is still missing. The aim of this study was to evaluate the shape distinctiveness of the lumbar (L1-L5) vertebral body (VB) and neural arch (isthmus, lamina, vertebral canal, spinous, and transverse processes) in SP. Using a three-dimensional (3D) digitizer, the VB length, width, height, and sagittal wedging as well as the lengths of the isthmus, lamina spinous, and transverse processes of all lumbar vertebrae (L1-L5) were measured from 115 male skeletons with bilateral SP at L5 and compared with 120 normal ones. Compared with the normal group, the following results were indicated in SP [analysis of variance (ANOVA), P < 0.05]: the VB's are significantly longer at the superior surfaces of L1-L4 and inferior surfaces of L1-L3 (total mean difference = 7.61 mm and 3.94 mm, respectively), and wider at the superior surfaces of L1-L4 and inferior surfaces of L1-L5 (total mean difference = 10.06 mm and 12.90 mm, respectively); The L5 VB is significantly shorter posteriorly (mean difference = 3.05 mm) and more lordotic (+1° of dorsal wedging); L5 is manifested with longer lamina (mean difference = 1.85-2.18 mm), longer isthmus (mean difference = 3.24-4.69 mm), and longer and wider vertebral canal (mean differences = 3.64 mm and 1.13 mm, respectively); The L2-L5 spinous processes are significantly longer (total mean difference = 7.45 mm). Clinically, detecting the aforementioned unique lumbar vertebral morphometric features in individuals suffering from chronic low back pain may facilitate the early diagnosis of SP.

Hip Pain or Injury - Soccer

HISTORY: 41 year -old male complains of right buttock pain. He was initially injured during a soccer game where he reported kicking the ground instead of the ball. He complains of a burning sensation and pain to his right buttocks with occasional sensory changes to anterior thigh. He denies lower back pain, weakness or bowel and bladder dysfunction. Pain is worsened with prolonged standing >10 min and with movement. PHYSICAL EXAMINATION: Range of motion of lumbar spine and bilateral lower extremities normal except limited internal rotation of right hip. Strength, sensation, and deep tendon reflexes of the bilateral lower extremities intact. Slump test negative, straight leg raise negative bilaterally. Positive Trendelenberg's sign to right lower extremity. Tenderness to palpation over right piriformis muscle. DIFFERENTIAL DIAGNOSIS: 1. Lumbar radiculopathy 2. Peripheral nerve injury-Gluteal nerves 3. Piriformis Syndrome 4. Lumbosacral plexus injury TEST AND RESULTS: MRI L-spine - Grade 1 anteriolisthesis L4 and L5 with questionable bilateral spondylolysis. Bilateral foraminal narrowing with right greater than left. EMG of right lower extremity - Severe right superior gluteal nerve injury. - No evidence of a right lumbosacral radiculopathy CT of Pelvis without contrast - Asymmetric enlargement of the right piriformis muscle in the area of the right superior gluteal nerve FINAL WORKING DIAGNOSIS: Isolated superior gluteal neuropathy secondary to piriformis compression TREATMENT AND OUTCOMES: - Prior to referral to our clinic, patient underwent physical therapy and lumbar stabilization program for suspected lumbar radiculopathy without clinical response - Medrol dose pack with moderate improvement but return of symptoms after completion - Gabapentin treatment for neuropathic pain with limited relief - At our initial consultation suspicion of superior gluteal neuropathy/piriformis syndrome led to EMG and advanced imaging - Right piriformis injection under fluoroscopic guidance and electrical stimulation for confirmation of correct needle placement - Resolution of symptoms after injection with improved function - Full return to activity and sports

Dilated cisterna chyli

A 46-year-old man was referred to our department because of chronic low back pain. A magnetic resonance (MR) examination of the spine revealed bilateral spondylolysis at the level of the lumbar vertebra L4, with associated anterolisthesis as well as degenerative disk disease at L4-L5. Additionally an oval-shaped hypointense structure was seen in the prevertebral space extending from the L1-L2 to L2-L3 level (arrows) on sagittal T1-weighted MR imaging (Fig. A). Axial T2-weighted MR imaging with a HASTE sequence showed a well delineated structure (arrow) adjacent and to the right of the abdominal aorta (Fig. B). The location, shape and fluid content were consistent with a focal dilatation of the cisterna chyli. Conservative therapy for low back pain was initiated. Because of the benign nature of the prevertebral structure, no further therapy was required.

Biomechanical rationale of sacral rounding deformity in pediatric spondylolisthesis: a clinical and biomechanical study

Rounding surface of the sacral dome and wedging deformity of the vertebral body are commonly observed in patients with isthmic spondylolisthesis. Recently, an animal study showed that the deformity can be caused by the growth plate involvement in the immature pediatric vertebral body after biomechanical alteration due to the pars defects. However, the pathomechanism and biomechanics of these deformities have yet to be clarified. To demonstrate that the sacral rounding deformity observed in pediatric patients with spondylolisthesis can be reversed, and to understand the pathomechanism of the deformity from the biomechanical standpoint by analyzing changes of stress around the growth plate of the vertebral body due to spondylolysis. Three-dimensional finite element pediatric lumbar models of the L3-L5 segment were utilized. Unlike the adult model, this pediatric model had growth plates and apophyseal rings. We analyzed stress distribution in response to 351°N axial compression and 10 N m moment in flexion, extension, lateral bending, and axial rotation. Bilateral spondylolysis was created in the model at the L4 level. The stress in the bilateral defect model was compared to the intact model predictions and the results obtained in the pediatric patients with sacral rounding deformity. Two patients presented rounding deformity of the anterior upper corner at S1 at the initial visit. They were asked to stop sports activities and use a soft trunk brace. Twelve months later, no rounding deformity was observed on the radiographs indicating that this deformity was reversible in pediatric cases. The biomechanical study indicated that in the pediatric spondylolytic spine, mechanical stress increased at the anterior upper corner during lumbar motion. In the presence of spondylolysis, mechanical stress increases in the growth plate at the anterior upper corner. Repetitive increases of mechanical stress may cause rounding deformity of the sacral dome mediated by growth plate involvement. When mechanical stress at the growth plate is reduced by wearing a brace, the proper functioning of the growth plate can help to remodel the sacral dome to its normal shape.