Magnetic resonance imaging findings in patients with dropped head syndrome.

BACKGROUND: Dropped head syndrome (DHS) is difficult to diagnose only by clinical examination. Although characteristic images on X-rays of DHS have been studied, changes in soft tissue of the disease have remained largely unknown. Magnetic resonance imaging (MRI) is useful for evaluating soft tissue, and we therefore performed this study with the purpose of investigating the characteristic signal changes of DHS on MRI by a comparison with those of cervical spondylosis. METHODS: The study involved 35 patients diagnosed with DHS within 6 months after the onset and 32 patients with cervical spondylosis as control. The signal changes in cervical extensor muscles, interspinous tissue, anterior longitudinal ligament (ALL) and Modic change on MRI were analyzed. RESULTS: Signal changes of cervical extensor muscles were 51.4% in DHS and 6.3% in the control group, those of interspinous tissue were 85.7% and 18.8%, and those of ALL were 80.0% and 21.9%, respectively, suggesting that the frequency of signal changes of cervical extensor muscles, interspinous tissue and ALL was significantly higher in the DHS group (p < 0.05). The presence of Modic change of acute phase (Modic type I) was also significantly higher in the DHS group than in the control group (p < 0.001). CONCLUSION: MRI findings of DHS within 6 months after the onset presented the characteristic signal changes in cervical extensor muscles, interspinous tissue, ALL and Modic change. Evaluation of MRI signal changes is useful for an objective evaluation of DHS.

Use of residual neural network for the detection of ossification of the posterior longitudinal ligament on plain cervical radiography.

Ossification of the posterior longitudinal ligament (OPLL) causes serious problems, such as myelopathy and acute spinal cord injury. The early and accurate diagnosis of OPLL would hence prevent the miserable prognoses. Plain lateral radiography is an essential method for the evaluation of OPLL. Therefore, minimizing the diagnostic errors of OPLL on radiography is crucial. Image identification based on a residual neural network (RNN) has been recognized to be potentially effective as a diagnostic strategy for orthopedic diseases; however, the accuracy of detecting OPLL using RNN has remained unclear. An RNN was trained with plain lateral cervical radiography images of 2,318 images from 672 patients (535 images from 304 patients with OPLL and 1,773 images from 368 patients of Negative). The accuracy, sensitivity, specificity, false positive rate, and false negative rate of diagnosis of the RNN were calculated. The mean accuracy, sensitivity, specificity, false positive rate, and false negative rate of the model were 98.9%, 97.0%, 99.4%, 2.2%, and 1.0%, respectively. The model achieved an overall area under the curve of 0.99 (95% confidence interval, 0.97-1.00) in which AUC in each fold estimated was 0.99, 0.99, 0.98, 0.98, and 0.99, respectively. An algorithm trained by an RNN could make binary classification of OPLL on cervical lateral X-ray images. RNN may hence be useful as a screening tool to assist physicians in identifying patients with OPLL in future setting. To achieve accurate identification of OPLL patients clinically, RNN has to be trained with other cause of myelopathy.

Relationship between cervical and global sagittal balance in patients with dropped head syndrome.

BACKGROUND: DHS is characterized by chin-on-chest deformity and devastatingly impedes activities of daily living in affected individuals. There is a paucity of literature about the pathophysiology of DHS including knowledge about spinal sagittal alignment. We conducted this study to clarify the relationship between cervical sagittal alignment and global sagittal balance in DHS. METHODS: This is a retrospective radiographic study of a case series of DHS. Forty-one patients with diagnosed DHS were enrolled. Measurements were made using lateral standing radiograph. RESULTS: C2-C7 sagittal vertical axis (SVA) was estimated as 52.0 ± 2.4 mm. Among sagittal parameters, C7-S1 SVA positively correlated with C2-C7 angle (C2-C7 A) (r = 0.33). For the correlations between C7 and S1 SVA and C2-C7 A, both logistic and linear regression models were used to determine the threshold for C2-C7 A value responsible for global sagittal balance. C2-C7 A of - 15.0 and 6.0 were predicted by logistic and linear regression models and were considered responsible for the occurrence of global positive imbalance. Therefore, we divided into two groups, namely, cervical kyphosis group (C type) and diffuse kyphosis group (D type) by median value of C2-C7 A. Enlarged thoracic kyphosis and global positive imbalance were observed in D type compared to C type. CONCLUSION: C2-C7 A exhibited correlations with cervical balance and also with global balance. There should be various type of thoraco-lumbar alignment in DHS. These slides can be retrieved under Electronic Supplementary Material.

The factors related to the poor ADL in the patients with osteoporotic vertebral fracture after instrumentation surgery.

PURPOSE: Osteoporotic vertebral fracture (OVF) with nonunion or neurological deficit may be a candidate for surgical treatment. However, some patients do not show improvement as expected. Therefore, we conducted a nationwide multicenter study to determine the predictors for postoperative poor activity of daily living (ADL) in patients with OVF. METHODS: We retrospectively reviewed the case histories of 309 patients with OVF who underwent surgery. To determine the factors predicting postoperative poor ADL, uni- and multivariate statistical analyses were performed. RESULTS: The frequency of poor ADL at final follow-up period was 9.1%. In univariate analysis, preoperative neurological deficit (OR, 4.1; 95% CI, 1.8-10.3; P < 0.001), perioperative complication (OR, 3.4; P = 0.006), absence of preoperative bone-modifying agent (BMA) administration (OR, 2.7; P = 0.03), and absence of postoperative recombinant human parathyroid hormone (rPTH) administration (OR, 3.9; P = 0.006) were significantly associated. In multivariate analysis, preoperative neurological deficit (OR, 4.6; P < 0.001), perioperative complication (OR, 3.4; P = 0.01), and absence of postoperative rPTH administration (OR, 3.9; P = 0.02) showed statistical significance. CONCLUSIONS: Preoperative neurological deficit, perioperative complication, and absence of postoperative rPTH administration were considered as predictors for postoperative poor ADL in patients with OVF. Neurological deficits and complications are often inevitable factors; therefore, rPTH is an important option for postoperative treatment for OVF. These slides can be retrieved under Electronic Supplementary Material.

Impact of Spinopelvic sagittal alignment on the surgical outcomes of dropped head syndrome: a multi-center study.

BACKGROUND: Most of the previous studies about the surgical treatment of dropped head syndrome (DHS) are small case series, and their primary outcome measures were cervical alignment parameters. Therefore, little is known about the associations between pre- and postoperative global sagittal alignment in the whole spine and the clinical outcomes of the surgical treatment of DHS. In this study, we investigated the surgical outcomes of DHS, including correction of cervical and global spinal sagittal alignment. METHODS: This study was a retrospective observational study. Fifteen patients with DHS who had undergone correction surgery were enrolled. Surgical outcomes, including complications and implant failures, were investigated. We assessed cervical alignment parameters as well as spinopelvic global alignment parameters, including pelvic incidence (PI), lumbar lordosis (LL), and C7-sacral sagittal vertical axis (SVA). We examined the changes in these parameters using pre- and posoperative whole spine lateral radiographs. The parameters were compared between the failure and nonfailure groups. RESULTS: Recurrence of sagittal imbalance and horizontal gaze difficulty was observed in 6 cases (40%). In all, 3 cases (20%) exhibited a distal junctional failure and required multiple surgeries with extension of fusion. Of all the radiographic parameters compared between the failure and nonfailure groups, significant differences were only observed in pre and postoperative SVA and PI-LL. CONCLUSIONS: Our results suggest that the global sagittal alignment parameters, including PI-LL and SVA, were different between the patients with failure and non failure, and these parameters might have notable impacts on surgical outcomes. Surgeons should consider PI-LL and SVA while determining the surgical course for patients with DHS.

Impact of pelvic incidence on change in lumbo-pelvic sagittal alignment between sitting and standing positions.

PURPOSE: Lumbo-pelvic sagittal alignment is affected by pelvic incidence (PI), and the PI represents the compensatory capacity of lumbo-pelvic sagittal alignment. The purpose of this study was to analyze changes in lumbo-pelvic sagittal alignment between the standing and sitting positions and to analyze its association with PI. METHODS: This study included 253 subjects (160 men and 93 women; age 53.6 ± 7.4 years). The subjects were divided into three groups (younger age group (YG), from 20 to 49 years; middle age group, from 50 to 69 years, and older age group (OG), of 70 years and above). Lumbar lordotic angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), and the associations between the changes in LL (∆LL), SS (∆SS), PT (∆PT), and PI were analyzed. RESULTS: In the YG, the amount of change in LL, SS, and PT was larger than in the OG. These parameters correlated with age in the standing position but not in the sitting position. On the other hand, in all groups, there were positive correlations between PI and changes between the standing and sitting positions. Multiple logistic regression analysis demonstrated that ∆LL = 3.81 - 0.72 × PT + 0.52 × PI, ∆SS = - 4.50 - 5.3 × PT + 0.34 × PI, and ∆PT = - 9.1 + 3.5 × PT - 0.21 × PI. CONCLUSIONS: Change in lumbo-pelvic parameters between the sitting and standing positions correlated with PI. These slides can be retrieved under Electronic Supplementary Material.

Differences in cervical sagittal alignment between the standing and sitting positions.

BACKGROUND: Sagittal spinal alignment has mainly analyzed in the standing position. According to previous studies, there are significant differences in lumbopelvic alignment between the standing and sitting positions and cervical alignment is affected by lumbopelvic alignment. In this study, therefore, we hypothesized that cervical sagittal alignments are different between the standing and sitting positions. METHODS: A total of 108 patients with spinal degenerative diseases underwent whole spine radiography. Cervical lordosis (CL), C2-7 SVA, T1S, C7-S1 SVA, TK, LL, SS, PT, and PI were measured in the standing and sitting positions. Patients were classified into 3 groups according to the changes in CL (ΔCL, CL in the sitting position - CL in the standing position); ΔCL < -3° (Decreased group: DG; 28.7%), -3° ≤ ΔCL ≤ 3° (Unchanged group: UG; 41.7%), and ΔCL > 3° (Increased group: IG; 29.6%). RESULTS: The parameters of the UG in the standing position were closer to the ideal alignment (SRS-Schwab classification). In the DG, CL, T1S, and C7-S1 SVA in the standing position were significantly higher than in the UG. In the IG, PI-LL in the standing position was significantly higher than in the UG. In the sitting position, pelvis was rotated posteriorly (decrease in SS and increase in PT) and lumbar lordosis was flattened (decrease in LL) in all groups, and C2-7 SVA was significantly higher in the DG than in the UG. CONCLUSIONS: CL was different between the standing and sitting positions in 58.3% of individuals. However, patients with good spinal sagittal alignment appeared to not undergo any changes in cervical alignment. Our results suggest the possibility that patients who had a positive imbalance and large PI-LL mismatch in the standing position had decreased CL and increased CL, respectively, when in the sitting position.

Overview of dropped head syndrome (Combined survey report of three facilities).

BACKGROUND: Dropped head syndrome (DHS) is a low prevalence and the clinical features remain unclear. The purpose of the present study was to clarify the general overview of DHS. METHODS: The subjects were 67 consecutive DHS patients (17 men and 50 women; average age 72.9 ± 10.2 years) presenting difficulty of horizontal gaze in up-right position. The patients' background, global spinal alignment, clinical findings and treatment were analyzed. RESULTS: The peak population of DHS was 75-79-year-old females. The comorbidities included Parkinson's disease in 9 cases, minor trauma in 9 cases, post-cervical operation in 3 cases, mental depression in 3 cases, malignant tumor in 3 cases, diabetes mellitus in 2 cases and rheumatoid arthritis in 2 cases. The C2-C7 cervical coronal vertical axis was distributed more to the right side (2.6 ± 12.8 mm). Regarding sagittal alignment, 24 cases (35.8%) showed negative balanced DHS (N-DHS) and 43 cases (64.2%) showed positive balanced DHS (P-DHS). There were significant differences in C2-C7 angle, T1S, LL and PI-LL between the two groups. Cervical or back pain was present in 62 cases (92.5%), and average numerical rating scale was 3.0 ± 2.6. Fourteen cases (20.9%) recovered (average 11.3 months), but 29 cases (43.3%) did not recover without surgery. Twenty-four cases (35.8%) underwent surgery, 20 for cervical spine and 4 for thoraco-lumbar spine, and horizontal gaze difficulty was improved in all patients post-surgery. CONCLUSION: DHS was mainly observed in elderly women. About 20% of DHS patients recovered without surgical treatment. DHS was accompanied by scoliosis in 37.3% of the cases.

Contrast-enhanced Magnetic Resonance Imaging in Patients With Dropped Head Syndrome.

STUDY DESIGN: This is a retrospective study of a consecutive case series of dropped head syndrome (DHS). OBJECTIVE: To identify the characteristic features of contrast-enhanced magnetic resonance imaging (MRI) in DHS patients. SUMMARY OF BACKGROUND DATA: Isolated neck extensor myopathy DHS is thought to be caused by severe cervical extensor muscle weakness from age-related loss of elasticity. However, the MRI findings of the cervical extensor muscles in DHS patients have not yet been characterized. MATERIALS AND METHODS: The subjects were 34 patients with isolated neck extensor myopathy DHS who underwent contrast-enhanced MRI within seven months after onset and 32 patients with age-matched cervical spondylosis or cervical soft-tissue tumor as controls. The presence of enhanced findings in the cervical extensor muscles, the involved cervical levels, and the characteristically enhanced shape of those muscles were evaluated using contrast-enhanced MRI. RESULTS: In the DHS group, the contrast-enhanced MRI showed pronounced enhancement at splenius capitis in 34 cases, rhomboid in 23 cases, semispinalis cervicis in seven cases, and levator scapulae in three cases. In the non-DHS group, none of those extensor muscles were enhanced. The enhanced pattern was butterfly shaped in 29 cases (85.3%) and linear in five cases (14.7%). All were located at the spinous process attachment at C6 or C7 in the DHS group. In the non-DHS group, seven cases presented an enhanced image of the spinous process, with C5-6 in one case, C6 in five cases, and C7 in one case. CONCLUSIONS: In DHS, contrast-enhanced MRI showed intramuscular enhancement of the cervical extensor muscles, which was not present in non-DHS cases. The enhanced muscles included the splenius capitis muscle in all cases. These findings may be useful for developing a strategy for DHS treatment.

Association of Lumbar Spondylolytic Spondylolisthesis With the Incidence and Prognosis of Anterior Ring Apophyseal Abnormalities of the Vertebrae in Young Gymnasts.

Background: Although anterior apophyseal abnormalities of the vertebrae and spondylolytic spondylolisthesis (SS) are prevalent in gymnasts during growth spurts, no studies have examined the relationship between apophyseal abnormalities and SS. Hypothesis: A significant relationship will exist between anterior apophyseal abnormalities and SS in young gymnasts. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 306 gymnasts (123 male, 183 female; age range, 6-28 years) with >2 weeks of back pain were enrolled in this study. Apophyseal abnormalities were evaluated using radiography. In the primary analysis, multiple logistic regression analysis was performed to assess the odds ratio (OR) for multivariate factors (age, body mass index, sex, skeletal maturity, competitive level, and presence of spondylolysis or SS) influencing the incidence of apophyseal abnormalities. In the secondary analysis, 90 of the 306 gymnasts were followed up radiographically for a minimum of 2 years, and factors contributing to the worsening of apophyseal abnormalities were identified. Results: In the primary analysis, the chi-square test revealed a relationship between anterior ring apophyseal abnormalities and SS at the L5-S1 segment (OR, 7.6). Multiple logistic regression analysis demonstrated that the presence of SS at L5-S1 (OR, 9.5) and competitive level (international: OR, 6.7; national: OR, 4.5) correlated with the incidence of apophyseal abnormalities. The secondary analysis identified the presence of SS at L5-S1 (OR, 5.9) as a significant factor contributing to the worsening of apophyseal abnormalities. Conclusion: The presence of SS was a factor affecting the incidence and prognosis of anterior apophyseal abnormalities.

Safety and Efficacy of All-In-One Percutaneous Pedicle Screw System.

STUDY DESIGN: Retrospective study of the prospectively collected outcomes data. OBJECTIVE: The indications for PPS placement during minimally invasive spine stabilization (MISt) procedures have increased in recent years. To the best of our knowledge, no studies have documented the outcomes of PPS insertion using the all-in-one PPS system. This study compared the conventional methods and the use of all-in-one percutaneous pedicle screw (PPS) system with respect to the speed and accuracy of PPS placement. We also determined the advantages associated with the use of the all-in-one PPS system. METHODS: We evaluated 54 patients who underwent PPS insertion using the conventional method and the all-in-one PPS system during MISt procedures. We also assessed the number of implanted PPSs, the time taken to implant PPSs, and the accuracy of PPS placement based on postoperative computed tomography images. RESULTS: A total of 254 PPSs were inserted (126 using the conventional method and 128 using the all-in-one PPS system). The PPS insertion time with the all-in-one PPS system (mean, 25.3 ± 9.1 s) was significantly shorter than that using the conventional method (mean, 63.1 ± 13.0 s; P < 0.01). With respect to the accuracy of PPS insertion, ≥ 2 mm pedicle breach was noted in one case each in both groups. CONCLUSIONS: PPS placement using the all-in-one PPS system is as safe as conventional methods and has the potential to save the surgical time of MISt procedures.

Global Sagittal Spinal Compensation for Dropped Head Alignment.

STUDY DESIGN: This is a retrospective radiographic study of a consecutive series of cases in patients with dropped head syndrome (DHS) at a single tertiary referral center. OBJECTIVE: The aim was to clarify the compensation among parameters of spinal sagittal alignment in patients with DHS. SUMMARY OF BACKGROUND DATA: The treatment strategy for DHS should vary according to the types of global sagittal spinal alignment. However, theoretical evidence in consideration of spinal sagittal compensation against the dropped head condition is lacking. MATERIALS AND METHODS: One hundred sixteen patients diagnosed with isolated neck extensor myopathy were enrolled. Radiographic measurements were made, including parameters of spinal sagittal alignment. The patients were divided into three groups according to sagittal spinal balance: C7SVA (sagittal vertical axis) ≥ +50 mm (P-DHS; positive imbalanced DHS), -50 mm ≤C7SVA <+50 mm (B-DHS; balanced DHS), and C7SVA <-50 mm (N-DHS; negative imbalanced DHS). Correlations among the various spinal parameters were analyzed. RESULTS: Among all types of DHS, there was no correlation between C2-C7 angle (C2-C7A) and T1 slope. In B-DHS, other correlations among the adjacent spinal segments were maintained. In N-DHS, there was no correlation between C2-C7A and TK, and in P-DHS, there was also no correlation between TK and lumbar lordosis. CONCLUSIONS: The loss of compensation at the cervicothoracic junction was observed in all DHS types. B-DHS showed decompensation only at the cervicothoracic junction. N-DHS presented additional decompensation of the thoracic spine, and P-DHS showed decompensation between the thoracic and lumbar spine. Evaluation of global sagittal spinal balance is important for determining global spinal compensation associated with DHS and when considering treatment strategy.

Balloon kyphoplasty combined with percutaneous pedicle screw (PPS) for the treatment of osteoporotic thoracolumbar fractures has minimum correction loss 2 years after surgery: compared to vertebroplasty using hydroxyapatite block combined with PPS.

BACKGROUND: Balloon kyphoplasty (BKP) is a useful treatment performed in patients with painful osteoporotic vertebral body fracture (OVF). However, in cases with large intra-vertebral clefts and cases with posterior spinal tissue damage, adjacent vertebral body fractures (AVFs), and cement migration may occur early after BKP, which may be a factor for poor results. In such cases, percutaneous vertebroplasty (PVP) combined with percutaneous pedicle screw (PPS) is useful treatment. This study compared BKP combined with PPS (BKP + PPS) compared to PVP using hydroxyapatite (HA) block combined with PPS (HAVP + PPS) for thoracolumbar OVF (TLOVF). METHODS: Twenty-eight patients who sustained painful TLOVFs without neurologic deficits underwent HAVP + PPS (group H, n=14) or BKP + PPS (group B, n=14). We evaluated time from injury to surgery, pre- and post-operative visual analogue scale (VAS) of low back pain, wedging angle of fractured vertebra, duration of operation, intraoperative blood loss, number of instrumented vertebra, and length of stay at hospital. RESULTS: Group B had significantly less surgery time and less blood loss during surgery. VAS of low back pain improved equally in both groups, but at 1 year and 2 years postoperatively, wedging angle of fractured vertebra progressed significantly in group H compared with group B. CONCLUSIONS: PPS fixation combined with percutaneous vertebral cement augmentation with BKP for OVF was suggested to be minimally invasive in the elderly patients. In addition, there is no correction loss of the fractured vertebral body after BKP + PPS, which is considered to be a useful surgical procedure.

Long-term reoperation rates and causes for reoperations following lumbar microendoscopic discectomy and decompression: 10-year follow-up.

OBJECTIVE: To investigate the 10-year rates and causes of reoperations following lumbar microendoscopic discectomy for disc herniation (MEDH) and microendoscopic decompression for spinal stenosis (MEDS), as well as to define the reoperations at index and different lumbar levels. METHODS: Between June 2005 and May 2011, the same surgeon had been using MEDH and/or MEDS on 355 consecutive patients. The follow-up rate was 88.3%. The causes and rates of reoperations (RORs) were determined at 10 years after the initial operations. RESULTS: The 10-year reoperation rate for all patients combined was 22.1% (67/303). The 10-year reoperation rate for all cases that underwent repeat operations in the same segment was 16.5% (50/303); the most frequent reason for reoperation (FRR) was recurrence of disc herniation (ROR, 25/251 = 9.96%), the second FRR was an increase of postoperative spondylolisthesis and/or instability (ROR, 8/303 = 2.64%), and the third FRR was surgical site infection (ROR, 5/303 = 1.65%). Ten-year reoperation rate for all cases that underwent repeat operation at different lumbar levels was 5.61% (17/303); the most FRR was new disc herniation at another lumbar level (ROR, 10/303 = 3.30%), the second FRR was residual segmental stenosis (ROR, 4/303 = 1.32%), and the third FRR was new segmental stenosis at other lumbar levels (ROR, 2/303 = 0.66%). CONCLUSIONS: Three-fourths of all repeat operations were conducted in the same segment and one-fourth were performed at different lumbar levels. We believe that it is important to understand and prevent related problems.

Eight cases of sudden-onset dropped head syndrome: patient series.

BACKGROUND: As the proportion of elderly people continues to increase, the number of patients with dropped head syndrome (DHS) also grows. However, the relationship between onset and clinical course of DHS has hardly been studied, particularly, that of sudden-onset DHS has not been reported and remains unclear. OBSERVATIONS: Sudden-onset DHS was defined as presenting with chin on chest deformity within 3 days from the time of awareness of cervical weakness. Sixty-six patients with DHS visited our facility. Among them, 8 of the total cases (12.1%) had experienced sudden onset DHS (6 females and 2 males; average age: 71.9 ± 10.9 years). Six of 8 cases showed recovery by conservative treatment, whose first interventions were from 0.1 to 12 months, but 3 experienced recurrence. Diffuse spinal kyphotic-type DHS was seen in 2 cases, and both had recurring horizontal gaze disturbance after initial recovery. Two unimproved cases underwent surgery of combined anterior and posterior cervical fixation, and their first interventions were at 5 and 24 months. After surgery, cervical sagittal alignment was improved, and they could walk maintaining horizontal gaze. LESSONS: Sudden-onset DHS can be expected to have a better outcome, but recurrence is possible in global imbalanced-type DHS.

Cervical sagittal alignment in patients with dropped head syndrome.

BACKGROUND: Dropped head syndrome (DHS) can be divided into two types, the positive sagittal vertical axis (SVA) type and the negative SVA type. However, the cervical sagittal alignment of DHS including global sagittal spinal alignment and the typical cervical alignment of the types of DHS is still unclear. The purpose of this study was to clarify the character of cervical sagittal alignment of DHS and analyze the relationship between cervical sagittal alignment and global sagittal spinal alignment. METHODS: The subjects were 35 DHS patients (10 men, 25 women, mean 71.1 years old). They were divided into two groups: negative DHS (N-DHS group, SVA < 0 mm) and positive DHS group (P-DHS group, SVA ≥ 0 mm). As control, 28 age-matched cervical spondylosis patients (CS, 21 men, 7 women, mean 67.4 years old) were analyzed. The following parameters were measured on lateral global-spine standing radiographs: cervical SVA (C2-C7SVA), O-C2A (O-C2 angle), C2 slope (C2S), C2-7A (C2-7 angle), T1 slope (T1S) and C7SVA. RESULTS: The results of measurements of each of the averaged sagittal alignment parameters were (CS, P-DHS, N-DHS): C2-7SVA(26.2 mm, 47.3 mm, 44.5 mm), O-C2 angle (35.0°, 37.1°, 39.3°), C2S (16.5°, 31.4°, 33.8°), C2-7A (9.3°, 9.9°, -16.6°), T1S (22.9°, 39.7°, 25.7°), C7SVA (35.3 mm, 51.0 mm, -43.1 mm). C2-C7SVA and C2S were significantly larger in both types of DHS compared to CS. Comparing P-DHS with N-DHS, C2-C7A and T1S were significantly smaller in N-DHS. CONCLUSIONS: O-C2A did not differ significantly among CS, P-DHS and N-DHS. In DHS patients, C2-7SVA and C2S were significantly larger than those of CS regardless of the type of DHS. The typical cervical sagittal alignment of DHS was different between P-DHS and N-DHS. In P-DHS, C2-7A and T1S were larger than those in N-DHS and the imbalance of thoraco-lumbar alignment should be noted.

The impact of sagittal imbalance on walking in patients with lumbar spinal canal stenosis.

PURPOSE: Gait and posture disorder severely impedes the quality of life of affected patients with lumbar spinal canal stenosis (LSCS). Despite the major health concern, there is a paucity of literature about the relationships among spatiotemporal gait parameters and spinal sagittal parameters. This is a cross sectional study performed in a single tertiary referral center to determine the relationships among spatiotemporal gait parameters and spinal sagittal parameters in patients with LSCS. METHODS: A total of 164 consecutive patients with LSCS, 87 men and 77 women with mean age of 70.7 years, were enrolled. Spatiotemporal gait parameters were studied using a gait analysis system. Spinal sagittal parameters were studied including sagittal vertical axis (SVA), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic inclination (PI), and pelvic tilt (PT) both in the neutral and stepped positions. RESULTS: SVA was significantly larger in the stepped position than in the neutral position (neutral position, 72.5 mm; stepped position, 96.8 mm; p = 0.003). Parameters regarding the pelvis exhibited significant differences, which could represent pelvic anteversion in the stepped position. By stepwise multiple regression analysis, the prediction models, containing SVA (neutral) and PT (stepped) for double supporting phase, exhibited statistical significance, and accounted for approximately 50% of the variance. CONCLUSIONS: The present study provides statistically established evidence of correlation among spatiotemporal gait parameters and spinal sagittal parameters. Differences between sagittal parameters in neutral and stepped position may stand for the postural control during gait cycle, and increased SVA in neutral position and increased PT in stepped position may correlate with prolonged double supporting phase.

Long-Term Outcomes Following Lumbar Microendoscopic Decompression for Lumbar Spinal Stenosis with and without Degenerative Spondylolisthesis: Minimum 10-Year Follow-Up.

OBJECTIVE: To determine whether preoperative presence of degenerative lumbar spondylolisthesis (DS) worsens the minimum 10-year outcome of patients undergoing microendoscopic decompression (MED) for lumbar spinal stenosis (SS). METHODS: Eighty patients undergoing MED were classified into 2 groups: DS group (34 SS with DS patients) and SS group (46 SS without DS patients). The degrees of improvement (DOIs) by the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and intensities of improvement (IOIs) by Visual Analog Scale (VAS) at 120-159 (mean, 138.4) months after MED of the DS and SS groups were statistically compared. Patients with DS were classified into 2 groups based on the effectiveness by VAS or JOABPEQ: effective group (E group: IOI or DOI ≥20) and ineffective group (I group). All preoperative radiologic measurements were statistically compared between the E and I groups. RESULTS: Significant decreases in low back pain, leg pain, and numbness, as measured by VAS, were noted at follow-up in the DS and SS groups. The effectiveness rates of pain-related disorders, lumbar spine dysfunction, and gait disturbance by JOABPEQ were almost equally high in the DS and SS groups. Statistical comparisons of the DOIs in all 5 functional scores and IOIs in low back pain, leg pain, and numbness showed no significant differences between the DS and SS groups. No significant differences were confirmed between the E and I groups concerning preoperative spondylolisthesis and instability. CONCLUSIONS: Our study indicated that preoperative DS did not worsen the outcome of patients with SS undergoing MED.

Evaluation of low back pain using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire for lumbar spinal disease in a multicenter study: differences in scores based on age, sex, and type of disease.

BACKGROUND: The Japanese Orthopaedic Association (JOA) has investigated the JOA Back Pain Evaluation Questionnaire (JOABPEQ) to evaluate several aspects of low back pain in patients. The score includes five categories (25 items) selected from the Roland Morris Disability Questionnaire and Short Form 36, and a visual analogue scale. Japanese physicians have recently used these scores to evaluate back pain; however, the efficacy has not been fully explored in large-scale studies. In the current study, we used the JOABPEQ to evaluate lumbar spinal disease in 555 patients (with lumbar disc herniation, lumbar spinal stenosis, and lumbar disc degeneration/spondylosis) in multiple spine centers and compared the results based on age, sex, and type of disease. METHODS: A total of 555 patients who had low back or leg pain were selected in 22 hospitals in Chiba Prefecture. Spine surgeons diagnosed their disease type based on symptoms, physical examination, radiography images, and magnetic resonance imaging. In all, 486 patients were diagnosed with spinal stenosis (239 patients), disc degeneration/spondylosis (143 patients), or disc herniation (104 patients). The other 69 patients were diagnosed with spondylolysis (16 patients) or other diseases (53 patients). The pain score in all patients was evaluated using the JOABPEQ (from 0 to 100, with 0 indicating the worst pain). RESULTS: The age of the patients was 56.1 +/- 13.3 years (mean +/- SD); the age of patients in the disc herniation and disc degeneration/spondylosis group was significantly lower than that in the spinal stenosis group. The average JOABPEQ scores in all patients were, for low back pain, 47.1; lumbar function, 53.6; walking ability, 54.8; social life function, 48.7; and mental health, 48.3. The low back pain score in men was significantly worse than that in women. In contrast, the mental health score in women was significantly higher than that in men. The low back pain score in patients <40 years old and the walking ability score in patients >65 years old were significantly lower than those scores in other patients. Based on the disease type, low back pain, lumbar function, social life function, and mental health scores for patients with disc herniation were significantly worse than for those with spinal stenosis. CONCLUSION: JOABPEQ scores were evaluated for several lumbar diseases. The average of five categories of JOABPEQ scores in all patients was similarly distributed. However, the average scores in the five categories were significantly different depending on age, sex, and type of disease. Compared with prior mass data (baseline data on the observational cohort of the Spine Patient Outcomes Research Trial in the United States), many data were similar based on the type of disease in the current study. Furthermore, the JOABPEQ is easy to use compared with the SF-36. Hence, we concluded that the JOABPEQ could be used worldwide as a tool for evaluating low back pain.

Global sagittal spinal alignment at cervical flexion in patients with dropped head syndrome.

PURPOSE: Dropped head syndrome (DHS) is characterized by the passively correctable chin-on-chest deformity. The characteristic feature is emphasized in the cervical flexion position. The purpose of this study was to analyze the influence of cervical flexion on sagittal spinal alignment in patients with DHS. METHODS: The study included 15 DHS subjects and 55 cervical spondylosis (CS) subjects as the control group. The following parameters were analyzed: cervical sagittal vertical axis (C-SVA), occipitoaxial angle (O-C2A), C2 slope (C2S), C2-C7 angle (C2-C7A), T1 slope (T1S), sagittal vertical axis, T1-T4 angle (T1-T4A), T5-T8 angle (T5-T8A), T9-T12 angle, lumbar lordosis, sacral slope, and pelvic tilt, in cervical flexion and neutral positions. RESULTS: The values of C-SVA, O-C2A, C2S, and T1S were significantly different between CS and DHS at cervical neutral and flexion positions. C2-C7A showed significant difference in cervical neutral position, but the difference disappeared in flexion position. T1-T4A did not present a significant difference, but T5-T8A showed a difference in neutral and flexion positions. CONCLUSIONS: Malalignment of DHS extended not only to cervical spine but also to cranio-cervical junction and thoracic spine, except T1-T4. It is known that global sagittal spinal alignment is correlated with adjacent parameters, although in DHS the reciprocal change was lost from cranio-cervical junction to the middle part of thoracic spine at cervical flexion.