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Study Design: This is a multicenter, prospective study.Purpose: This study aimed to evaluate the reproducibility of the walking test for patients with lumbar spinal stenosis (LSS).Overview of Literature: Walking test is one of the useful procedures to investigate cauda equina syndrome with lumbar spinal stenosis. One the other hands, there were few studies to investigate the reproducibility of this test.Methods: In this study, we prospectively examined 70 LSS patients with intermittent claudication symptoms at a multicenter outpatient clinic. A walking test was administered at baseline and week 4 to assess patients’ walking distance and lower limb pain and numbness. Immediately after the walking test, patients were asked to use the Visual Analog Scale (VAS) to rate their pain and numbness in the front, back, outside, inside, and hip of the lower legs. The reproducibility of the walking test was evaluated using Cohen’s κ analysis and intraclass correlation coefficients (ICCs). Meanwhile, the Swiss Spinal Stenosis (SSS) Questionnaire was used to evaluate the severity of the stenosis.Results: The walking distance ICC at baseline and at week 4 remained unchanged at 0.7, with acceptable interobserver reliabilities for lower limb pain and numbness in both legs. The average VAS score for lower leg pain was 23.2±25.2 mm at baseline and 27.4±28.8 mm at week 4, while the corresponding average VAS score for numbness was 23.4±26.7 mm at baseline and 24.8±25.2 mm at week 4. The ICC score was 0.7 for leg pain and 0.7 for numbness. The mean SSS was 30.2±5.5 at baseline and 29.2±5.2 at week 4, and there was no significant difference in the severity.Conclusions: The walking test for LSS has acceptable reproducibility.

Background The purpose of this study was to investigate whether walking speed is associated with postoperative pain catastrophizing in patients with lumbar spinal stenosis. Methods In this prospective observational study, consecutive patients with clinically and radiologically defined lumbar spinal stenosis underwent surgical treatment (decompression, or posterolateral or transforaminal lumbar interbody fusion) at Tottori University Hospital, between October 2015 and April 2018. The pain catastrophizing scale, walking speed, leg and back pain (numerical rating scale), and Japanese Orthopaedic Association score were evaluated preoperatively and at 3, 6, and 12 months postoperatively. Correlations between the pain catastrophizing scale and each variable were analyzed at each evaluation time point. The effect of walking speed on the pain catastrophizing scale was analyzed using mixed-effect models for repeated measurements. Results Ninety-four patients were included at baseline, and 83, 88, and 82 patients were analyzed at 3, 6, and 12 months postoperatively, respectively. The pain catastrophizing scale was significantly correlated with walking speed, leg pain, back pain, and the Japanese Orthopaedic Association score at all evaluation time points. The pain catastrophizing scale was associated with walking speed at all evaluation time points. Conclusions Our results suggest that changes in postoperative pain catastrophizing after lumbar spine surgery are associated with walking speed. Thus, walking speed is a necessary assessment for the management of pain catastrophizing and associated pain and disability in patients after lumbar spine surgery.

Background We developed a mobile device application and dedicated pelvic positioner with the aim of improving the acetabular cup placement accuracy in patients undergoing total hip arthroplasty (THA). The function of the application was to display the intra-operative cup angle. The accuracy and clinical usefulness of this combined method were verified through comparison with the conventional alignment guide method. Methods In total, 60 patients who underwent cementless THA were included in this study. We compared the cup alignment when using this combined method with that when using the conventional alignment guide method. The absolute value error between the intra- and post-operative angles of inclination and anteversion of the cup was calculated. Results The absolute value error of inclination was 2.4° ± 2.1° in the study group and 4.0° ± 3.3° in the control group (P = 0.107). The absolute value error of anteversion was 2.8° ± 2.6° in the study group and 7.4° ± 5.3° in the control group (P Conclusion Using the application and pelvic positioner is simple and can be introduced at a low cost. The more accurate measurement of the intra-operative cup angle using this combined method has improved the cup insertion accuracy compared with that of the conventional alignment guide method.

Background The purpose in this study is to investigate the T2 value of lumbar facet joint (FJ) in subjects without lumbar spinal disorders, age from 20s to 70s, using T2 mapping, and to evaluate the correlation between age and T2 value. And also, we investigated the T2 value of lumbar intervertebral disc (IVD) in the same way as FJ, and evaluated the correlation between the T2 value of FJ and that of IVD. Methods We investigated 60 volunteers (30 male, 30 female), who were recruited from six age groups, 20s–70s (10 subjects in each decade; 5 male, 5 female). We measured the T2 values of FJ at the L4/5 level in axial image and those of IVD (nucleus pulposus; NP, anterior and posterior annulus fibrosus; AAF and PAF) at the L4/5 level in midline sagittal image. We investigated the correlation between age and T2 value of FJ, and the correlation between the T2 value of FJ and that of IVD. Results There was a strong positive correlation between age and T2 value of FJ (r = 0.717). Age and T2 values of IVD were negatively correlated (NP; r = −0.728, AAF; r = −0.696, PAF; r = −0.580). There was a negative correlation between T2 value of FJ and that of IVD (NP; r = −0.575, AAF; r = −0.617, PAF; r = −0.492). Conclusions T2 value of FJ was significantly increased as age rose. Our results suggest that T2 mapping could detect the degenerative changes of FJ related to aging even in subjects without lumbar spinal disorders. The results of this study will be the reference data of FJ T2 value in order to evaluate the relationship between low back pain and FJ using T2 mapping.

Background Muscle and bone interactions might be associated with osteoporosis and sarcopenia. Urinary pentosidine and serum 25-hydroxyvitamin D (25(OH)D) might affect muscle and bone interactions. It is unclear whether these biomarkers are affected by age and sex or play a role in muscle and physical functions. We aimed to investigate the association between urinary pentosidine and serum 25(OH)D levels with muscle mass, muscle strength, and physical performance in community-dwelling adults. Methods Two-hundred and fifty-four middle-aged and elderly adults were enrolled. There was no significant difference in age between 97 men (75.0 ± 8.9 years) and 157 women (73.6 ± 8.1 years). The skeletal muscle mass index (SMI), grip strength, and gait speed were assessed. The urinary pentosidine level was measured. We evaluated the association of urinary pentosidine and serum 25(OH)D levels with age and sex (student’s t-test) and correlations between biomarker and each variable (Pearson’s correlation coefficients). Multiple regression analysis was performed with grip strength and gait speed as dependent variables and with age, height, weight, body mass index (BMI), speed of sound (SOS), SMI, glycated hemoglobin (HbA1c), estimated glomerular filtration rate (eGFR), 25(OH)D, and pentosidine as independent variables using the stepwise method. Results The urinary pentosidine level was negatively correlated with grip strength, gait speed, eGFR, and insulin-like growth factor-1 (IGF-1) in men and with SOS, grip strength, and gait speed in women. The serum 25(OH)D level was positively correlated with IGF-1 in women and grip strength in men. Grip strength was associated with age, height, and pentosidine in men and height and pentosidine in women. Gait speed was associated with age, BMI, and pentosidine in men and age, height, and pentosidine in women. Conclusion Urinary pentosidine levels are significantly associated with grip strength and gait speed and may serve as a biomarker of muscle and bone interactions.

Summary The incidence rate of hip fracture in Tottori Prefecture tended to increase until 2018 in men, but it did not increase after 2010 in women. By type of fracture, the incidence rate of femoral neck fractures also increased over time in men, but no other changes were observed from 2010. Purpose The aims of this study were to determine the sex-, age-, and fracture-type-specific incidence rates of hip fractures in Tottori Prefecture between 2007 and 2018 and to compare the results with our past results to identify changes over time. Methods All hip fractures in people aged 35 years or older living in Tottori Prefecture were surveyed from 2007 to 2018 throughout the entire prefecture, and the age- and sex-specific incidence rates were calculated. The incidence rates from 1986 to 1988, 1992 to 1994, 1998 to 2000, and 2004 to 2006 previously reported were used for the analysis. Results In men, the age-adjusted number of patients adjusted by demographic structure based on the mean incidence rate for each 3-year period from 1986 to 2018 showed an increase in incidence over time compared with the incidence for 1986–1988 (p < 0.001). In women, the incidence rose over time compared with the incidence for 1986–1988 until 2004–2006 (p < 0.001), and no further increase was observed from 2010. The age-specific incidence rates of neck fracture in men were higher in 2010–2012 and 2016–2018 compared with 2004–2006 (p < 0.001), but those in women showed no increase with time. Those of trochanteric fracture did not change over time in either men or women. Conclusion The hip fracture incidence rate in Tottori Prefecture, Japan, tended to increase until 2018 in men, but it did not increase after 2010 in women.

Case A 75-year-old man, who was a carpenter, experienced neck pain and numbness in the upper and lower extremities while hammering a nail and later developed a gait disturbance. Initial magnetic resonance imaging (MRI) revealed a tumor-like mass at the C5 epidural space compressing the spinal cord. The first diagnosis was cervical epidural hematoma. The following day, the patient's symptom deteriorated. A second MRI revealed an increase in the size of the mass, and surgery was performed. Operative findings included a juxtafacet cyst. Conclusion Repeated job-related load on the facet joint in this patient caused rapid progression of facet cysts, causing myelopathy similar to an epidural hematoma.

[Study Design] Multicenter, prospective study. [Purpose] To investigate the effects of diabetes mellitus (DM) on surgical outcomes in patients with cervical myelopathy. [Overview of Literature] To date, few studies have investigated the influence of postoperative blood glucose or glycated hemoglobin (HbA1c) levels on surgical outcomes. [Methods] The participants were patients who underwent surgery for the treatment of cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament. The 61 cases were evaluated preoperatively and 1 year postoperatively using the Japanese Orthopaedic Association (JOA) scores and the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). The study variables included fasting blood glucose and HbA1c levels measured preoperatively and at 1 week, 4 weeks, and 1 year postoperatively; the F-wave conduction velocity, latency, rate of occurrence, and M-wave latency in the ulnar and tibial nerves were measured preoperatively and at 1 year postoperatively. The patients were divided into a group without diabetes (N group, 42 patients) and a group with diabetes (DM group, 19 patients). We then assessed the associations between the surgical outcomes and each of the study variables. [Results] JOA scores significantly improved in both groups; however, no significant between-group differences were found. There was no significant improvement in the JOACMEQ scores, which assessed cervical function, upper and lower limb function, and bladder function in both groups. We then subdivided the DM group into those with a good control of HbA1c after 1 year (DMG group, 12 patients) and those with HbA1c deterioration after 1 year (DMB group, seven patients), prior to comparing the surgical outcomes. The JOACMEQ scores for upper and lower limb function significantly improved in the DMG group (p

Background Low back pain (LBP) is one of the most common ailments that people experience in their lifetime. On the other hands, Sarcopenia also leads to several physical symptoms and contributes to reducing the quality of life of elderly people.The purpose of this study is to investigate the association between sarcopenia and low back pain among the general population. Methods The subjects included 216 adults (79 men and 137 women; mean age, 73.5 years) undergoing a general medical examination in Hino, Japan. Skeletal muscle index (SMI), The percentage of young adults’ mean (%YAM) of the calcaneal bone mass using with quantitative ultrasound (QUS) method and walking speed were measured, and subjects who met the criteria of the Asian Working Group for Sarcopenia were assigned to the sarcopenia group. Subjects with decreased muscle mass only were assigned to the pre-sarcopenia group, and all other subjects were assigned to the normal group. Then, we compared the correlations with low back pain physical finding. The Oswestry Disability Index (ODI) and the low back pain visual analogue scale (VAS) were used as indices of low back pain. Statistical analysis was performed among three groups with respect their characteristic, demographics, data of sarcopenia determining factor, VAS and ODI. We also analysed prevalence of LBP and sarcopenia. We investigated the correlations between ODI and the sarcopenia-determining factors of walking speed, muscle mass and grip strength. Results Sarcopenia was noted in 12 subjects (5.5%). The pre-sarcopenia group included 38 subjects (17.6%), and the normal group included 166 subjects (76.9%). The mean ODI score was significantly higher in the sarcopenia group (25.2% ± 12.3%; P

Study DesignProspective study.PurposeTo examine the changes in body sway using stabilometry in patients who underwent cervical laminoplasty for cervical myelopathy.Overview of LiteratureAlthough the patients of cervical myelopathy complain body sway there are few report to examine body sway objectively.MethodsPatients who received treatment for cervical myelopathy between October 2010 and February 2013 were included. Twenty-one patients underwent cervical laminoplasty (myelopathy group). Body sway was assessed using stabilometry, wherein patients stood on a stabilometer with their eyes closed for 30 seconds. The Romberg ratio, outer peripheral area (OPA) with eyes closed (cm2), and total locus length per unit area (L/A) with eyes closed (/cm) were examined. Examinations were performed preoperatively (at baseline) and at 8 weeks postoperatively. Examination results of patients in the myelopathy group were compared with those of 17 healthy individuals (control group). Clinical symptoms were evaluated using the Japanese Orthopaedic Association scale score (JOA score) and the timed up and go (TUG) test.ResultsIn the myelopathy and control groups, the mean baseline Romberg ratio, OPA, and L/A were 2.3±1.2, 8.9±5.5 cm2, and 14.2±5.3/cm and 1.4±1.0, 4.3±2.8 cm2, and 23.7±10.1/cm, respectively. Eight weeks after laminoplasty, only L/A showed significant improvement from baseline in the myelopathy group (23.2±10.1 to 16.8±7.9; p=0.03). The Romberg ratio and OPA showed improvement in the myelopathy group, but the changes were not statistically significant. JOA scores and TUG test results in this group significantly improved from baseline to 8 weeks after laminoplasty (12.7 to 13.4 and 10.8 to 8.0 seconds, respectively; both pConclusionsL/A is a useful parameter for measuring body sway to assess the recovery of body sway after laminoplasty.

Background Understanding interactions between bone and muscle based on endocrine factors may help elucidate the relationship between osteoporosis and sarcopenia. However, whether the abundance or activity of these endocrine factors is affected by age and sex or whether these factors play a causal role in bone and muscle formation and function is unclear. We aimed to evaluate the association of serum bone- and muscle-derived factors with age, sex, body composition, and physical function in community-dwelling middle-aged and elderly adults. Methods In all, 254 residents (97 men, 157 women) participated in this cross-sectional study conducted in Japan. The calcaneal speed of sound (SOS) was evaluated by quantitative ultrasound examination. Skeletal muscle mass index (SMI) was calculated by bioelectrical impedance analysis. Grip strength was measured using a dynamometer. Gait speed was measured by optical-sensitive gait analysis. Serum sclerostin, osteocalcin (OC), insulin-like growth factor-1 (IGF-1), myostatin, and tartrate-resistant acid phosphatase-5b (TRACP-5b) concentrations were measured simultaneously. The difference by sex was determined using t test. Correlations between serum bone- and muscle-derived factors and age, BMI, SOS, SMI, grip strength, gait speed, and TRACP-5b in men and women were determined based on Pearson’s correlation coefficients. Multiple regression analysis was performed using the stepwise method. Results There was no significant difference with regard to age between men (75.0 ± 8.9 years) and women (73.6 ± 8.1 years). Sclerostin was significantly higher in men than in women and tended to increase with age in men; it was significantly associated with SOS and TRACP-5b levels. OC was significantly higher in women than in men and was significantly associated with TRACP-5b levels and age. IGF-1 tended to decrease with age in both sexes and was significantly associated with SOS and body mass index. Myostatin did not correlate with any assessed variables. Conclusions Sclerostin was significantly associated with sex, age, and bone metabolism, although there was no discernable relationship between serum sclerostin levels and muscle function. There was no obvious relationship between OC and muscle parameters. This study suggests that IGF-1 is an important modulator of muscle mass and function and bone metabolism in community-dwelling middle-aged and elderly adults.

The Gekkou-drill® is an industrial drill that is highly efficient due to reduced cutting resistance resulting from its characteristic drill point shape. In this experiment, we compared the degree of thermal damage to bone tissue caused by conventional medical drills and these same drills with Gekkou modifications. Holes were created in the tibias of living pigs using two different 3.2-mm diameter drills and their modified versions. Regarding the drilling parameters, the thrust force was 10 N and the drilling speeds were 800 revolutions per minute (rpm) and 1500 rpm. We compared the original and modified drills in terms of the bone temperature around the drill bit and the total time necessary to create each hole, the latter calculated using imaging data captured during drilling. In histopathological examination, the percentages of empty lacunae in osteocytes of the cortical bone beneath the periosteum were evaluated at 400 × magnification with an optical microscope. Compared to the original drills, the modified drills required significantly less time to create each hole and caused a significantly lower temperature rise during bone drilling. With the modified drills, the percentages of empty lacunae around the drilling holes were about 1/2–1/3 of those with the original drills, and were significantly lower for both drilling speeds. Gekkou-modified medical drills shortened drilling times despite low thrust force, and histopathological assessment demonstrated a significant reduction in osteocyte damage.

The pennation angle is an important architectural and functional feature of pennate muscles. The purpose of this study was to investigate the change in the pennation angle of the supraspinatus muscle after rotator cuff tear repair.The study included 68 patients who underwent arthroscopic rotator cuff repair and magnetic resonance imaging. The size of the tear was measured under arthroscopic visualization. The pennation angle of the supraspinatus both preoperatively and postoperatively and the integrity of the repaired cuff were determined by magnetic resonance imaging.The preoperative pennation angle was significantly greater with enlargement of the tear size (P .0001, analysis of variance). The retear rate was 29% in patients with medium tears and 59% in patients with large or massive tears. No retear was noted in patients with partial and small tears. The retear rate was 90.9% when the preoperative pennation angle was 20° or greater and was 12.3% when this angle was 19° or less, and the risk ratio for retear was 7.4 when this angle was 20° or greater. For repair-type tears, comparison between the preoperative and postoperative pennation angles showed a significant decrease in the mean value from 11.8° ± 3.7° to 9.9° ± 3.0° in the medium tear group (P = .007, paired t test) but no significant difference in the large or massive tear group (from 15.1° ± 7.0° to 13.3° ± 5.8°) (P = .33). For retear-type tears, no significance was found between groups.The preoperative pennation angle is directly correlated with the tear configuration and could be one of the prognostic factors for postoperative cuff integrity. To restore the pennation angle, primary repair is more appropriate in smaller rotator cuff tears than in medium-sized tears.

Study Design An international, multicenter cross-sectional image-based study performed in 33 institutions in the Asia Pacific region. Objective The study addressed the role of facet joint angulation and tropism in relation to L4–L5 degenerative spondylolisthesis (DS). Methods The study included 349 patients (63% females; mean age: 61.8 years) with single-level DS; 82 had no L4–L5 DS (group A) and 267 had L4–L5 DS (group B). Axial computed tomography and magnetic resonance imaging were utilized to assess facet joint angulations and tropism (i.e., asymmetry between facet joint angulations) between groups. Results There was a statistically significant difference between group A (left mean: 46.1 degrees; right mean: 48.2 degrees) and group B (left mean: 55.4 degrees; right mean: 57.5 degrees) in relation to bilateral L4–L5 facet joint angulations ( p Conclusions In one of the largest studies assessing facet joint orientation in patients with DS, greater sagittal facet joint angulation was associated with L4-L5 DS, with a critical value of 58 degrees or greater increasing the likelihood of the condition for unilateral and bilateral facet joint involvement. Specific facet joint tropism categories were noted to be associated with DS.

Study Design A multinational, multiethnic, cross-sectional image-based study was performed in 33 institutions, representing 10 countries, which were part of the AOSpine Asia Pacific Research Collaboration Consortium. Objective Lumbar facet joint orientation has been reported to be associated with the development of degenerative spondylolisthesis (DS). The role of ethnicity regarding facet joint orientation remains uncertain. As such, the following study was performed across a wide-ranging population base to assess the role of ethnicity in facet joint orientation in patients with DS in the Asia Pacific region. Methods Lateral standing X-rays and axial magnetic resonance imaging scans were obtained for patients with lumbar DS. The DS parameters and facet joint angulations were assessed from L3–S1. Sex, age, body mass index (BMI), and ethnicity were also noted. Results The study included 371 patients with known ethnic origin (mean age: 62.0 years; 64% males, 36% females). The mean BMI was 25.6 kg/m2. The level of DS was most prevalent at L4–L5 (74.7%). There were 28.8% Indian, 28.6% Japanese, 18.1% Chinese, 8.6% Korean, 6.5% Thai, 4.9% Caucasian, 2.7% Filipino, and 1.9% Malay patients. Variations in facet joint angulations were noted from L3 to S1 and between patients with and without DS ( p 0.05); however, increasing age was found to increase the degree of angulation throughout the lumbar spine ( p 0.05). Ethnic variations were noted in non-DS L5–S1 facet joint angulations, predominantly between Caucasian, Chinese, and Indian ethnicities ( p Conclusions This study is the first to suggest that ethnicity may not play a role in facet joint orientation in the majority of cases of DS in the Asia-Pacific region. Findings from this study may facilitate future comparative studies in other multiethnic populations. An understanding of ethnic variability may assist in identifying those patients at risk of postsurgical development or progression of DS. This study also serves as a model for large-scale multicenter studies across different ethnic groups and cultural boundaries in Asia.

The number of spinal infections has been increasing due to aging populations and larger numbers of immunocompromised hosts and intravenous drug users. Magnetic resonance imaging is a useful tool for the early diagnosis of spinal infections, and can yield positive findings just 3-5 days after disease onset. Before antibiotic administration, cultures must be initiated from blood and from specimens collected from the locus of infection. Based on the pathogens identified by culture, appropriate antibiotics should be selected with careful consideration of antimicrobial susceptibility and spinal tissue penetration. Antibiotic treatment of spinal infections should be continued for longer than for most other types of infections, although the optimal duration remains unknown. The indications for surgical treatment include progressive neurologic deficits, progressive deformity, spinal instability, persistent or recurrent infection, and unbearable pain. In most patients with spinal infection, the gold standard surgical treatment is anterior radical debridement followed by autologous strut bone grafting. The addition of posterior instrumentation has recently become popular. This procedure may be performed alone as an alternative surgical option in patients in poor condition, and if it dramatically reduces pain, subsequent observation may be reasonable. If progressive deformity is observed or pain relief is inadequate after posterior instrumentation, additional anterior debridement and bone grafting should be scheduled.

Since in all studies of conservative treatment of lumbar compartment syndrome the follow-up duration was less than 6 months, it is difficult to draw firm conclusions. To report a patient with lumbar paraspinal compartment syndrome who was treated conservatively over a follow-up period of 2 years. This is a case report of a 23-year-old male college student with lumbar paraspinal compartment syndrome who was treated conservatively. We report a case of a 23-year-old male college student with lumbar paraspinal compartment syndrome who was treated conservatively. We repeatedly checked his physical examination, laboratory tests, lumbar compartment pressures, and magnetic resonance imaging, and surgical teams were readily prepared to operate should the patient’s condition worsen. To prevent complications of rhabdomyolysis, hydration and alkalization were performed. We followed him up to 2 years after discharge. Although the temporal changes on MRI up to the 1-year point, the patient continued to have no symptoms. Conservative therapy can be recommended if rhabdomyolysis is under control.

Retrospective nationwide questionnaire-based survey of complications.To elucidate the incidence of complications and risk factors associated with lateral interbody fusion (LIF).After its introduction to Japan in February 2013, the numbers of LIF cases have increased substantially because of the advantages of this minimally invasive procedure. However, LIF has the potential risk of several complications unique to the procedure. Although there are many reports of complications, no nationwide survey has been conducted.Questionnaires were sent to all Japanese Society for Spine Surgery and Related Research (JSSR) members. Questionnaires requested information about surgical procedures (XLIF or OLIF), patient characteristics, preoperative diagnosis, complications, salvage procedures, final outcomes, and the surgeon's experience of LIF. The data from replies received between March 2013 and April 2015 were recorded on a web site and the details of complications were analyzed by a JSSR research team.Seventy-one institutions (12.3%) answered "yes" to LIF experience and 2998 cases (1995 XLIF and 1003 OLIF) were enrolled in this study. The response rate was 86.1%. A total of 540 complications were reported, of which 474 (84.8%) could be further analyzed. The overall complication rate was 18.0%. The most frequent complications were sensory nerve injury (5.1%) and psoas weakness (4.3%) and the majority resolved spontaneously. The rates of major vascular injury, bowel injury, and surgical site infection were 0.03%, 0.03%, and 0.7%, respectively. The overall reoperation rate was 2.2%. Higher rates of sensory nerve injury and psoas weakness were reported for XLIF and higher rates of peritoneal laceration and ureteral injury were reported for OLIF.A nationwide survey of complications associated with LIF was conducted. Although the majority of complications were minor, a relatively high rate of complications was reported. Approach-related specific features of the two procedures were identified.4.

Objective Medial radial displacement (MRD) of the medial meniscus is a feature proving a dysfunction in the medial meniscus in osteoarthritis (OA) of the knee. MRD was measured in radiographic pre-OA knee and early osteoarthritis of the knee (early-OA) longitudinally using ultrasound (US) to investigate the characteristics involved in the onset and progression of OA. Methods Fifty-five patients with pain on the medial side of the knee participated in the present study. It was possible to follow-up 46 patients for 5 years, and, thus, they were divided into 32 pre-OA patients (female: 59%, mean age: 69.0 years) and 14 early-OA patients (female: 78%, mean age: 74.4 years) based on radiography at the baseline time-point. MRD was measured in standing and supine positions at baseline and after 1 and 5 years using US. MRD corrected with the skeletal size, i.e., the medial displacement index (MDI), was analyzed. The pre- and early-OA groups were divided into subgroups at 5 years: stable and OA progression groups, following the Kellgren/Lawrence classification, and ⊿MDI (gap of the MDI between the standing and supine positions) were retrospectively compared between the subgroups at baseline, 1 and 5 years. Results In the overall pre-OA group, MDI increased by 7% and 10% at 5 years in the supine and standing position, showing a significant increase (P = 0.044, 0.0147). ⊿MDI was significantly greater in the subgroup with OA progression in the pre- and early-OA groups (P = 0.02 and 0.03, respectively), and was continuously 6–7% in the pre-OA progression group, showing that the displacement rate was 2-fold or higher than in the stable group. Conclusion An increase in ⊿MDI on US may be an important risk factor for the disease stage progression of OA and useful as a feature predicting the onset of radiographic knee OA.

There have been a few reports on the surgical outcomes of cervical myelopathy in diabetic patients; however, those studies included ossification of the posterior longitudinal ligament. This study investigated whether surgical outcome of expansive laminoplasty (ELAP) for diabetic patients with cervical spondylotic myelopathy (CSM) differs from that for non-diabetic patients and determined prognostic factors in diabetic patients.We retrospectively reviewed 78 patients with CSM after excluding the cases with other medical conditions, which could affect surgical outcome from 222 consecutive patients who had undergone ELAP between 2000 and 2008 in our hospital. The patients were divided into two groups: diabetic patients (Group 1) and non-diabetic patients (Group 2). We evaluated differences in age, gender, pre- and postoperative Japanese Orthopaedic Association (JOA) score, recovery rate (RR), symptom duration, and postoperative complications between the two groups. In Group 1, the correlation between RR and factors indicating the severity of diabetes mellitus was assessed.There were 13 patients in Group 1 and 65 in Group 2. There was no significant difference in age, gender, JOA score before or after surgery, or symptom duration between the two groups. Group 1 showed poorer recovery of sensory and motor function in the lower extremities. A negative correlation was observed between RR and the preoperative hemoglobin A(1c) (HbA(1c)) level in Group 1.Diabetic patients experienced benefits from ELAP similar to non-diabetic patients. A negative correlation between RR and preoperative HbA(1c) level suggests that strict blood sugar control is recommended before surgery.

There have been few reports describing substances related to oxidative and intermediary metabolism in the cerebrospinal fluid (CSF) in patients with spinal degenerative disorders. This study investigated whether the concentrations of metabolites in the CSF differed between patients with spinal degenerative disorders and controls, and whether the concentrations of these metabolites correlated with the severity of symptoms. CSF samples were obtained from 30 patients with cervical myelopathy (Group M), 30 patients with lumbar radiculopathy (Group R), and 10 volunteers (control). Metabolites in these CSF samples were measured by nuclear magnetic resonance spectroscopy. There were no differences in the concentrations of lactate, alanine, acetate, glutamate, pyruvate, or citrate between Groups M and R, between Group M and the control, or between Group R and the control. In Group M, neither symptom duration nor the Japanese Orthopaedic Association score correlated with the concentration of any metabolite. In Group R, the symptom duration positively correlated with the concentration of lactate, glutamate, and citrate in CSF. The duration of nerve root block showed a negative correlation with the concentrations of acetate in CSF of the patients in Group R. In patients with lumbar radiculopathy, there is a possibility of increased aerobic metabolic activity or decreased gluconeogenic activity in patients with shorter symptom duration, and increased aerobic metabolic activity in patients with severe inflammation around a nerve root.

An osteoid osteoma of the cervical spinal pedicle is rare and carries a high surgical risk because of the close anatomic relationship to the spinal cord, nerve root, and vertebral artery. We report the case of a 12-year-old girl with an osteoid osteoma of the C2 pedicle. Computed tomograms showed an oval nidus and marked sclerosis around this lesion at the right C2 pedicle. There also was expansion of the medial and inferior cortical bone of the C2 pedicle. After failure of nonoperative treatment, we planned surgery. Owing to concerns regarding thermal damage to the spinal cord, nerve root, and/or vertebral artery using computed tomography (CT)-guided radiofrequency ablation, we curetted the nidus using a navigation system. Twenty-eight months after surgery, her pain was relieved with no limitation of cervical movement and there has been no evidence of recurrence. Navigation allowed safe curettage of the nidus through a small hole while maintaining spinal stability.

There have been few reports describing cytokines in the cerebrospinal fluid (CSF) of patients with spinal degenerative disorders. This study investigated whether interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) could be detected in CSF of patients with cervical myelopathy or lumbar radiculopathy and whether the concentrations of those cytokines correlated with the severity of disease conditions. CSF samples were obtained from 21 patients with cervical myelopathy (Group M) and 19 patients with lumbar radiculopathy (Group R), and six volunteers (control). The concentration of IL-6 was significantly higher in Groups M and R than in the control, possibly demonstrating spinal cord and nerve root damage, respectively. However, TNF-alpha was lower than the detection limit. IL-1beta was detected in only five samples from three patients in Group M and two volunteers in the control. The concentrations of IL-6 did not show any correlation with symptom duration, the scoring system by the Japanese Orthopaedic Association, or the duration of nerve root block. There is a possibility that the concentration of inflammatory cytokines in CSF can indicate certain pathological aspects of cervical myelopathy or lumbar radiculopathy.

Study design Retrospective multi-institutional study Objective To describe the surgical outcomes in patients with ossification of the posterior longitudinal ligament in the thoracic spine (T-OPLL) and to clarify factors related to the surgical outcomes. Summary of background data Detailed analyses of surgical outcomes of T-OPLL have been difficult because of the rarity of this disease. Methods The subjects were 154 patients with T-OPLL who were surgically treated at 34 institutions between 1998 and 2002. The surgical procedures were laminectomy in 36, laminoplasty in 51, anterior decompression via anterior approach in 25 and via posterior approach in 29, combined anterior and posterior fusion in 8, and sternum splitting approach in 5 patients. Instrumentation was conducted in 52 patients. Assessments were made on (1) The Japanese Orthopedic Association (JOA) scores (full score, 11 points), its recovery rates, (2) factors related to surgical results, and (3) complications and their consequences. Results (1) The mean JOA score before surgery was 4.6 +/- 2.0 and, 7.1 +/- 2.5 after surgery. The mean recovery rate was 36.8% +/- 47.4%. (2) The recovery rate was 50% or higher in 72 patients (46.8%). Factors significantly related to this were location of the maximum ossification (T1-T4) (odds ratio, 2.43-4.17) and the use of instrumentation (odds ratio, 3.37). (3) The frequent complications were deterioration of myelopathy immediately after surgery in 18 (11.7%) and dural injury in 34 (22.1%) patients. Conclusion The factors significantly associated with favorable surgical results were maximum ossification located at the upper thoracic spine and use of instrumentation. T-OPLL at the nonkyphotic upper thoracic spine can be treated by laminoplasty that is relatively a safe surgical procedure for neural elements. The use of instrumentation allows correction of kyphosis or prevention of progression of kyphosis, thereby, enhancing and maintaining decompression effect, and its use should be considered with posterior decompression.

UNLABELLED Treatment of cervical myelopathy in elderly patients is controversial. We retrospectively studied 113 patients who had decompression surgery from 1990-2001 to clarify how pre-operative conditions, duration of symptoms, involved levels, surgical outcomes, and complications differ between younger and elderly patients. We also asked whether elderly patients would likely have reasonable outcomes of surgery. The patients were divided into five age groups: Group 1, 36-45 years (12 patients); Group 2, 46-55 years (22 patients); Group 3, 56-65 years (31 patients); Group 4, 66-75 years (32 patients); and Group 5, 76-85 years (16 patients). The duration of symptoms was similar among the five groups. The involved level was more cephalic in the older groups, and the most frequently involved level in patients older than 75 years was C3-C4. Neurologic symptoms were more severe preoperatively and postoperatively in older patients. The recovery ratio also was lower in older patients; however, in Group 5 it was 36.9%, which indicated that patients older than 75 years could regain approximately 40% of their function postoperatively. Decompression surgery can be a reasonable treatment option for cervical myelopathy, even in elderly patients. LEVEL OF EVIDENCE Therapeutic Study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

This is the first case report of a child with isthmic spondylolisthesis and discitis who had spontaneous fusion develop at an unstable level with relief of symptoms after nonoperative treatment. Although the blood culture was negative, the 14-year-old boy with Grade III isthmic spondylolisthesis of L5 was diagnosed with discitis at the L5-S1 level, based on clinical findings, elevated C-reactive protein, plain radiographs, and magnetic resonance imaging scans. The patient was treated with antibiotics for 19 weeks and bed rest for 4 weeks followed by immobilization in a hip spica cast for 8 weeks and a thoracolumbosacral orthosis for an additional 12 weeks. The lumbar back pain improved and there was a decrease in C-reactive protein to the normal range 3 weeks after onset. Forty months from onset, the patient was free from lumbar back or leg pain and his clinical neurologic examination was normal. Plain radiographs showed spontaneous fusion between L5 and the sacrum. This suggests that nonoperative treatment is acceptable even if discitis occurs at an unstable level.

Study design Magnetic resonance images of cervical compression myelopathy were retrospectively analyzed in comparison with surgical outcomes. Objectives To investigate which magnetic resonance findings in patients with cervical compression myelopathy reflect the clinical symptoms and prognosis, and to determine the radiographic and clinical factors that correlate with the prognosis. Summary of background data Signal intensity changes of the spinal cord on magnetic resonance imaging in chronic cervical myelopathy are thought to be indicative of the prognosis. However, the prognostic significance of signal intensity change remains controversial. Methods The participants in this study were 73 patients who underwent cervical expansive laminoplasty for cervical compression myelopathy. Their mean age was 64 years, and the mean postoperative follow-up period was 3.4 years. The pathologic conditions were cervical spondylotic myelopathy in 42 patients and ossification of the posterior longitudinal ligament in 31 patients. Magnetic resonance imaging (spin-echo sequence) was performed in all the patients. The transverse area of the spinal cord at the site of maximal compression was computed, and spinal cord signal intensity changes were evaluated before and after surgery. Three patterns of spinal cord signal intensity changes on T1-weighted sequences/T2-weighted sequences were detected as follows: normal/normal, normal/high-signal intensity changes, and low-signal/high-signal intensity changes. Surgical outcomes were compared among these three groups. The most useful combination of parameters for predicting prognosis was determined using a stepwise regression analysis. Results The findings showed 2 patients with normal/normal, 67 patients with normal/high-signal, and 4 patients with low-signal/high-signal change patterns before surgery. Regarding postoperative recovery, the preoperative low-signal/high-signal group was significantly inferior to the preoperative normal/high-signal group. There was no significant difference between the transverse area of the spinal cord at the site of maximal compression in the normal/high-signal group and the low-signal/high-signal group. A stepwise regression analysis showed that the best combination of surgical outcome predictors included age (correlation coefficient R = -0.348), preoperative signal pattern, and duration of symptoms (correlation coefficient R = -0.231). Conclusions The low-signal intensity changes on T1-weighted sequences indicated a poor prognosis. The authors speculate that high-signal intensity changes on T2 weighted images include a broad spectrum of compressive myelomalacic pathologies and reflect a broad spectrum of spinal cord recuperative potentials. Predictors of surgical outcomes are preoperative signal intensity change pattern of the spinal cord on radiologic evaluations, age at the time of surgery, and chronicity of the disease.

To clarify the priorities of the walking test and the treadmill test for intermittent claudication of lumbar canal stenosis. The study population comprised 45 subjects, with a mean age of 72.6 years. An investigator walked with the subjects during the walking test or watched the subjects walking on the treadmill machine in the treadmill test. The pain scales became significantly worse after the walking test. Ten patients who were diagnosed as root symptom type or cauda equine symptoms were subsequently diagnosed as mixed type by the walking test. The numbers of patients who experienced muscle weakness that was not revealed at rest were eight with the walking test and seven with the treadmill test. The numbers of patients who experienced sensory disturbance that was not observed at rest were seven with the walking test and two with the treadmill test. The walking test detected significantly more symptoms that were not detected at rest than the treadmill test.

Expansive laminoplasty for ossification of the posterior longitudinal ligament (OPLL) has had favorable outcomes. Many modifications of expansive laminoplasty have been developed, including expansive laminoplasty with and without spinous process spacers (SPS). The purpose of this study was to determine whether surgical outcomes were similar between expansive laminoplasty surgeries with and without SPS. Of 109 consecutive patients undergoing surgery for OPLL, 68 patients undergoing expansive laminoplasty were included in the study after excluding patients with other conditions affecting their functional status. The patients were divided into 2 groups based on their K-line, which connects the midpoints of the spinal canal at C2 and C7. Patients were further divided into 2 subgroups: those undergoing expansive laminoplasty without SPS (without SPS group) and those undergoing expansive laminoplasty with SPS (with SPS group). Surgical outcomes were evaluated between K-line (+) and K-line (−) groups. After dividing those groups further into the with SPS and without SPS groups, the differences in surgical outcomes were evaluated again. No significant difference existed in the recovery rate between the with SPS and without SPS groups and between the K-line (+) and K-line (−) groups. When the surgical outcome was only evaluated in the K-line (+) group, the recovery rate 1 year postoperatively was higher in patients without SPS than in those with SPS. Therefore, for patients with K-line (+), the possibility exists that SPS can restrict the posterior shift of the spinal cord and affect the surgical outcome.

Case: A 16-year-old girl with Pompe disease underwent surgery for scoliosis. She had been able to walk without any assistance, and kept her balance by swinging her waist. Therefore, we performed posterior selective spinal correction and fusion to avoid any adverse effects on walking ability that could occur with immobilization of the lumbosacral spine. After surgery, she was highly satisfied with her ability to perform the activities of daily living. Conclusion: For nonambulatory patients with scoliosis and Pompe disease, long fusion from the upper thoracic spine to the pelvis is generally required. However, in ambulatory patients, in order to maintain the ability to walk, selective spinal fusion is an alternative.

With increased aging of the population, spine surgeons have more opportunity to treat elderly patients for lumbar spinal stenosis (LSS). The purpose of this study was to clarify the clinical features and surgical outcomes for LSS in the elderly aged 80 years or older.We retrospectively reviewed 702 consecutive patients with LSS who underwent decompression surgery without fusion between 2006 and 2010. Patients with other conditions that could affect functional status were excluded from this study. Of the remaining 304 patients, 241 with LSS whose condition could be evaluated 6 months at least after surgery were analyzed. The mean follow-up period was 14.4 months (range 6-60 months). There were 144 males and 97 females aged 45-93 years old (average: 72.2 years old). Patients were divided into two age groups: 80 years or older (Group A, 46 patients) and under 80 years of age (Group B, 195 patients). We evaluated differences in the clinical features and surgical outcomes between the two groups.There were no significant differences in surgical levels, the number of operation levels, operation times, or the amount of intraoperative bleeding between Groups A and B. The percentages of patients with comorbidities were 73.9 % in Group A and 60.0 % in Group B, which were not significantly different. There were no significant differences in Japanese Orthopaedic Association scores preoperatively, 6 months postoperatively, and at the final follow-up between the two groups. Furthermore, recovery ratios 6 months postoperatively and at final follow-up were similar between the two groups. The percentages of patients with postoperative complications were 19.6 % in Group A and 13.3 % in Group B, which were not significantly different.This multi-center retrospective study demonstrated that the benefits and risks of decompression surgery for LSS were similar between patients aged over 80 years and those under 80 years. Therefore, decompression surgery is a reasonable treatment even for elderly patients aged over 80 years.

Advances in chemotherapy for various malignancies have contributed to the increased life expectancy of patients. If such a patient has a concurrent infection, his/her oncologist would hesitate to perform prompt chemotherapy owing to the risk of inducing sepsis. Therefore, the treatment of infection would have priority over initiating chemotherapy for the malignancy. We present a 69-year-old female with malignant lymphoma requiring prompt chemotherapy who also demonstrated spinal infection with Mycobacterium tuberculosis and a 66-year-old male with esophageal cancer who also demonstrated spinal infection with Staphylococcus aureus. Anterior debridement and interbody fusion were performed for both patients. One patient died of malignant lymphoma 4 years after surgery, and the other is still alive and has remained disease-free 4 years after surgery. Saving the life of a patient with malignancy would be difficult without prompt chemotherapy. Conservative treatment for spinal infection requires prolonged antibiotic treatment, and there is no guarantee that the spinal infection would be controlled only with antibiotics. Therefore, early surgical intervention would be an alternative option under such a condition.

There is a possibility that the patients with diffuse idiopathic skeletal hyperostosis (DISH) increase with aging of the population and progressive lengthening of life expectancy in developed countries. In the patients with DISH, even a trivial vertebral fracture may actually turn out to be a three-column injury because mechanical stress is applied to the fracture site due to the lever arm effect. Under these circumstances, even a prolonged strict immobilization often results in failure. Recently, elderly people increasingly wish to maintain physical abilities. We present three patients aged over 90 years with DISH sustaining lower thoracic vertebral fracture after minor trauma. Long fusion involving three vertebral levels above and below the fracture site was performed with pedicle screw system, and vertebroplasty was carried out by transpedicular filling with hydroxyapatite blocks. The patients’ activities of daily living were maintained close to the pre-injury level 1 year and 9 months, 2 years and 3 months, and 1 year after surgery, respectively. Many reports have recommended surgery over conservative treatments at vertebral fracture complicating DISH; however, there has been no report of vertebral fracture in patients aged over 90 years with DISH. Satisfactory results were obtained by surgical treatment in our three patients despite their age. We recommend posterior fusion with vertebroplasty just after injury for vertebral fracture in the elderly patients of advanced age with DISH to extend their healthy lifespan.

Japan has one of the most rapidly increasing numbers of elderly individuals; therefore, future trends in spinal infections in the elderly in other countries may be predicted by studying such characteristics in Japan. The purposes of this study were to identify whether the incidence of spinal infection in individuals more than 80 years old is increasing and to define its clinical characteristics.We retrospectively reviewed the medical records of 98 patients treated in our hospital for spinal infection between 1999 and 2008. Patients were divided into two groups: those admitted to our hospital during the initial five year period, and those admitted during the latter five year period. We evaluated changes in the percentage of individuals over the age of 80 years. To define the clinical characteristics of spinal infection, patients were also divided into another set of two groups: those over 80 years and those around the age of 80 years.The percentage of patients over 80 years with spinal infection was significantly increasing. There was no significant difference in the gender distribution, prevalence of immunocompromised hosts, common involved levels, or mortality rate between the two age groups. The pathogenic organism was isolated in 78.6%, and of these, the rate of methicillin-resistant Staphylococcus aureus or epidermidis was 2.46 times higher in the elderly group than in the younger group.The number of patients over 80 years with spinal infection is expected to rapidly increase in aging societies. This advanced age group is more susceptible to infection with drug-resistant organisms, which makes infection management more difficult.

We present the case of a 15-year-old boy with symptoms due to Klippel–Feil syndrome. Radiographs and CT scans demonstrated basilar impression, occipitalisation of C1 and fusion of C2/C3. MRI showed ventral compression of the medullocervical junction. Skull traction was undertaken pre-operatively to determine whether the basilar impression could be safely reduced. During traction, the C3/C4 junction migrated 12 mm caudally and spasticity resolved. Peri-operative skull-femoral traction enabled posterior occipitocervical fixation without decompression. Following surgery, cervical alignment was restored and spasticity remained absent. One year after surgery he was not limited in his activities. The surgical strategy for patients with basilar impression and congenital anomalies remains controversial. The anterior approach with decompression is often recommended for patients with ventral compression of the medullocervical region, but such procedures are technically demanding and carry a significant risk of complications. Our surgical strategy was an alternative solution. Prior to a posterior cervical fixation, without decompression, skull traction was used to confirm that the deformity was reducible and effective in resolving associated myelopathy.

With the aging of the population in developed countries, spine surgeons have recently been more likely to encounter elderly patients in need of treatment. This study investigated whether decompression surgery for cervical spondylotic myelopathy (CSM) in elderly patients aged 80 years or older would likely be a reasonable treatment. We retrospectively reviewed 605 consecutive patients with cervical myelopathy who underwent decompression surgery between 2004 and 2008. Patients with other conditions that could affect functional status or compression factors other than spondylosis were excluded from this study. Of the remaining 189 patients, 161 with CSM whose condition could be evaluated 6 months after surgery were analyzed. The patients were divided into two age groups: 80 years or older (Group A, 37 patients) and younger than 80 years of age (Group B, 124 patients). We evaluated the differences in symptom duration, clinical data, involved levels, surgical outcome, comorbidities, and postoperative complications between the two groups. The symptom duration was significantly shorter in Group A. The average JOA scores preoperatively and 6 months postoperatively were significantly lower in Group A; however, there was no significant difference in the recovery ratio. There were no significant differences in the percentages of patients with comorbidities or those with postoperative complications. Elderly patients aged 80 years or older regained approximately 40% of their function postoperatively, and the incidence of postoperative complication was similar to that in younger patients. Since this age group shows a rapid deterioration after onset, prompt decompression surgery is required.

We present the case of an 83-year-old man who developed quadriparesis and respiratory embarrassment following osteomyelitis at the occipito-atlantoaxial junction. He had developed an abscess at this site after an earlier urinary infection with methicillin-resistant staphylococcus aureus. Stabilisation of the neck and antibiotic therapy led to an almost complete neurological recovery without recourse to anterior surgery.

We retrospectively reviewed the medical charts of 210 consecutive patients treated for spinal infection in Tottori University Hospital in Japan between 1956 and 2005. Until 1995, spinal infection was under control in this series; however, during the last decade, it has been on the rise. Male predominance had been gradually progressing, and 69% of the patients were male during the last decade. Patients with spinal infection were aging, and the ratio of immunocompromised hosts dramatically increased to 53%. Until 1995, the percentage of patients with tuberculous spondylitis had been declining; however, the incidence has been on the rise during the last ten years. The organism was detected in 64% of patients treated between 1996 and 2005, of which Staphylococcus aureus was detected in 49%. Moreover, methicillin-resistant S. aureus was detected in 61% of patients with S. aureus. There were no immigrants or cases with human immunodeficiency virus in this series.

The purpose of this study was to investigate the relationship between intervertebral disk degeneration and bone mass. Magnetic resonance imaging was performed to evaluate lumbar disk degeneration according to Thompson's classification (grades 1 and 2, normal disk; grades 3, 4, and 5, degenerated disk), and bone mineral density (BMD) in the lumbar vertebrae, radius, and calcaneus was measured by dual-energy X-ray absorptiometry for 90 women (22–74 years old). The relationship between the grade of intervertebral disk degeneration and the BMD (Z score) was analyzed in pre- and postmenopausal women. In premenopausal women, BMD was significantly higher at all measured sites in the degenerated disk group judged at the L5–S1 level than in the normal disk group (P < 0.05). In postmenopausal women, BMD was significantly higher at the anteroposterior L2–L4, lateral L3, and calcaneus in the degenerated disk group judged at the L2–L3 level than in the normal disk group (P < 0.05). BMD at the anteroposterior L2–L4 and calcaneus was significantly higher in the degenerated disk group judged at the L3–L4 level than in the normal disk group (P < 0.05). In conclusion, the BMD of not only the lumbar vertebrae but also the calcaneus and radius was mutually related to lumbar intervertebral disk degeneration from an early stage of degeneration.

Introduction Degenerative spondylolisthesis (dSpl) can lead to various symptoms, including low back pain. Lumbar facet joint orientation has been reported to be associated with the development of dSpl. The role of ethnicity regarding facet joint orientation remains uncertain. As such, the following study was performed across a wide-ranging population base to assess the role of ethnicity in facet joint orientation in patients with dSpl in the Asia Pacific region. Materials and Methods A multinational, multiethnic cross-sectional image-based study was performed in 34 institutions in Asia Pacific, identifying 448 cases. Lateral standing X-rays and axial MRIs and/or CT scans were obtained for patients with lumbar dSpl. Magnitude of slip displacement, level of dSpl, and left/right facet joint angulation, width-curvature ratio, and gap width were noted on image assessment. Facet joint measurements were performed at each level from L3-S1. Gender, age, BMI, and ethnicity were also noted. Results The study included 389 patients with known ethnic origin (mean age: 61.4 years; 36.7% males, 63.3% females). The mean BMI was 25.6 kg/m2. The level of dSpl was most prevalent at L4/L5 (72.4%). There were 28.8% Indian, 28.5% Japanese, 17.5% Chinese, 8.2% Korean, 6.2% Thai, 4.6% Caucasian, 2.3% Filipino, 2.3% Malay, and 1.3 were of mixed Asian origin. Accounting for patient demographics and displacement, there was a statistically significant difference between ethnicity to that of left/right facet joint angulations, width-curvature ratios, and gap widths from L3-S1 between specific ethnic groups ( p < 0.05). Conclusion This is the largest study to address the role of ethnicity upon lumbar facet joint orientation in dSpl. Ethnicity plays a role in facet joint orientation and may influence the occurrence and severity of dSpl or be a potential consequence. An understanding of ethnic variability may be one factor which assists in identifying those patients at risk of postsurgical development or progression of dSpl. Acknowledgments This study was funded by AOSpine Asia Pacific. Disclosure of Interest None declared

Introduction Degenerative spondylolisthesis (dSpl) is translation of the vertebral body in relation to adjacent levels, mainly attributed to degenerative changes of the intervertebral disc and facet joint complexes, and primarily occurs at L4-L5. Studies have suggested that more sagittal oriented facet joints at L4-L5 are associated with dSpl. However, the role of facet joint tropism (i.e., asymmetry between facet joint orientations) in L4-L5 dSpl remains inconclusive, in particular, in an Asian population and possibly attributed to nonstandardized definitions of tropism. As such, the following study addressed the role of facet joint tropism in relation to L4-L5 dSpl in the Asia Pacific region. Materials and Methods A multinational, multiethnic cross-sectional image-based study was performed in 34 institutions in the Asia Pacific region. Lateral standing radiographs and axial MRIs and/or CT scans were obtained for patients diagnosed with lumbar dSpl. Imaging assessment consisted of the following: magnitude of slip displacement, level of spondylolisthesis, and left/right L4-L5 facet joint angulations were noted on image assessment. Patients with single level dSpl were included. Patients were further stratified into those presenting with (Group A) or without (Group B) L4-L5 dSpl. Facet joint tropism was defined as 7 degrees difference (Grogan et al 1997) between left and right facet joints and also assessed on receiver operating characteristics (ROC) curve analysis to identify critical values for multivariate analysis. Gender, age, weight/height (body mass index [BMI]), and ethnicity were also noted. Results The study included 351 patients (36.9% males and 63.1% females) with a mean age of 61.8 years (range: 24-90 years). The mean BMI was 25.6 kg/m2 (range: 15.4-43.9 kg/m2). There were 267 patients (76.1%) in Group A and 84 individuals (23.9%) in Group B (control). Sex type ( p = 0.295) and BMI ( p = 0.227) did not significantly differ between groups, but elevated age was more pronounced with L4-L5 dSpl ( p = 0.001). There was a statistically significant difference between right and left L4-L5 facet joint angulations between Group A (right mean: 57.5 degrees; left mean: 55.4 degrees) and Group B (right mean: 48.4 degrees; left mean: 46.5 degrees) ( p < 0.001). Based on facet joint tropism of 7 degrees difference between facet angulations, there was no statistically significant difference between groups. ROC analysis identified high sensitivity and specificity of facet joint angulation difference of 15 degrees or greater associated with dSpl. Based on age-adjusted multivariate analysis, facet joint tropism with a critical value of 15 degrees or greater angulation difference noted an odds ratio of 2.34 (95% CI: 1.17-4.67; p = 0.016) associated with dSpl. Slippage was noted with increased facet joint tropism, but the effects could not be discerned. Conclusion Greater sagittal FJ orientation was associated with dSpl, as was joint tropism. A critical value of 15 degrees FJ angle difference produced a twofold increased likelihood of dSpl. Our study broadens the understanding of FJ morphology and its role in degenerative sagittal plane instability. Acknowledgments This study was funded by AOSpine Asia Pacific. Disclosure of Interest None declared

Study design This report describes the cyst-subarachnoid shunt, a novel surgical treatment, for sacral cysts. Objective To introduce a new surgical technique for sacral cysts. Summary of background data There is no consensus on the appropriate treatment for symptomatic sacral cysts. The hydrostatic and pulsatile forces of cerebrospinal fluid are attributed to the growth of the cyst and their becoming symptomatic. Methods The clinical and radiologic features of a 41-year-old man with a symptomatic sacral cyst are detailed. A cyst-subarachnoid shunt was set to equalize the cerebrospinal fluid pressure between the cephalad thecal sac and the cyst. Results Immediately after surgery, the patient had no pain in his left leg and was free of pain at 2 years. Magnetic resonance imaging 1 year after surgery showed a decrease in the size of the cyst. Conclusion Although this is a preliminary study, a cyst-subarachnoid shunt can be a useful alternative for symptomatic sacral cysts.

We report the case of a 42-year-old woman with Klippel-Feil syndrome, who showed severe hypermobility of the upper cervical spine without neurological involvement for more than 40 years. Radiographs revealed the presence of the odontoid bone and fusion of the atlas, odontoid bone, and occiput. Congenital fusion was present from the axis to C5 as a block vertebra. Lateral flexion-extension radiographs revealed severe hypermobility at the junction between the odontoid bone and the axis. Prophylactic surgical stabilization has been recommended in patients with severe hypermobility, but adjacent disc problems may possibly occur at the unfused levels in the future. We believe that early prophylactic stabilization should not be indicated for Klippel-Feil syndrome without neurological involvement only because of hypermobility.

STUDY DESIGN The first case of intraspinal synovial cyst communicating with the C1-C2 facet joints and subarachnoid space associated with rheumatoid atlantoaxial instability is presented. OBJECTIVES To describe the diagnosis and successful treatment of a synovial cyst of the C1-C2 junction in a patient with rheumatoid arthritis and atlantoaxial instability. SUMMARY OF BACKGROUND DATA Intraspinal synovial cysts of the C1-C2 junction are extremely rare. Neither association with rheumatoid atlantoaxial instability nor communication with the C1-C2 facet joints and the subarachnoid space has been previously reported in a synovial cyst of the C1-C2 junction. MATERIALS AND METHODS The clinical and radiologic features of a 71-year-old woman with a symptomatic synovial cyst of the C1-C2 junction with rheumatoid atlantoaxial instability are detailed. Posterior atlantoaxial fusion alone was performed. RESULTS Preoperative magnetic resonance images demonstrated a large cystic mass around the dens, compressing the spinal cord. The mass was of low signal intensity on T1-weighted images, was of high signal intensity on T2-weighted images, and was enhanced marginally with gadolinium-DTPA on T1-weighted images. Computed tomograms performed after myelography disclosed the cyst around the dens communicating with the subarachnoid space and the C1-C2 facet joints. Spontaneous regression of the cyst was identified on the magnetic resonance images 3 months after surgery. One year after surgery, myelopathic symptoms were improved. CONCLUSION An intraspinal cyst communicating with the C1-C2 facet joints and subarachnoid space associated with rheumatoid atlantoaxial instability was reported. Computed tomograms after myelography were useful in delineating the relationships among the synovial cyst, facet joints, and the subarachnoid space. Spontaneous regression of the cyst and clinical improvement were achieved by C1-C2 posterior fusion alone.

A retrospective study of cervical expansive laminoplasty for cervical myelopathy from a clinicoradiologic perspective.To clarify the correlation among sagittal curvature of the cervical spine, cervical range of motion, sagittal plane translation, spinal cord atrophy, and myelopathic symptoms in patients who have undergone laminoplasty.Laminoplasties were developed to diminish the undesirable effects of laminectomy, which include postoperative kyphotic changes and instability. However, the superiority of laminoplasty over laminectomy remains controversial.Fifty-one patients with cervical spondylotic myelopathy or ossification of the cervical posterior longitudinal ligament who underwent laminoplasty were radiologically assessed before and after surgery. The index of the sagittal curvature, intervertebral range of motion, listhesis, and the transverse area of the spinal cord at the site of maximal compression were measured to evaluate interrelations among those parameters and myelopathic symptoms.There were no patients with kyphotic curvature before surgery. The postoperative curvature tended to be less lordotic. This tendency did not adversely affect postoperative symptoms. The intervertebral range of motion was significantly decreased except at C1-C2. The final C4-C5 range of motion and the postoperative myelopathic symptoms were negatively correlated. A significant correlation was observed between the postoperative spinal cord atrophy and the final myelopathic symptoms.The decrease in the lordotic curvature index and the decrease in the intervertebral range of motion after laminoplasty did not cause neurologic deterioration. In the C4-C5 intervertebral segment with a high incidence of listhesis, the restriction of the C4-C5 range of motion improved the clinical myelopathic symptoms. The radiologic prognostic factors were the postoperative restriction of intervertebral range of motion in preoperatively unstable segments and the anatomic reversibility of spinal cord insult.