BACKGROUND: Andersson lesions (ALs) are not uncommon in ankylosing spondylitis (AS). Plain radiography (PR) is widely used for the diagnosis of ALs. However, in our practice, there were some ALs in AS patients that could not be detected on plain radiographs. This study aimed to propose the concept of occult ALs and evaluate the prevalence and radiographic characteristics of the occult ALs in AS patients. METHODS: A total of 496 consecutive AS patients were admitted in the Affiliated Drum Tower Hospital, Medical School of Nanjing University between April 2003 and November 2019 and they were retrospectively reviewed. The AS patients with ALs who met the following criteria were included for the investigation of occult ALs: (1) with pre-operative plain radiographs of the whole-spine and (2) availability of pre-operative computed tomography (CT) and/or magnetic resonance imaging (MRI) of the whole-spine. The occult ALs were defined as the ALs which were undetectable on plain radiographs but could be detected by CT and/or MRI. The extensive ALs involved the whole discovertebral junction or manifested as destructive lesions throughout the vertebral body. Independent-samples t test was used to compare the age between the patients with only occult ALs and those with only detectable ALs. Chi-square or Fisher exact test was applied to compare the types, distribution, and radiographic characteristics between detectable and occult ALs as appropriate. RESULTS: Ninety-two AS patients with a mean age of 44.4 ± 10.1 years were included for the investigation of occult ALs. Twenty-three patients had occult ALs and the incidence was 25% (23/92). Fifteen extensive ALs were occult, and the proportion of extensive ALs was significantly higher in detectable ALs (97% vs. 44%, χ2 = 43.66, P < 0.001). As assessed by PR, the proportions of osteolytic destruction with reactive sclerosis (0 vs. 100%, χ2 = 111.00, P < 0.001), angular kyphosis of the affected discovertebral units or vertebral body (0 vs. 22%, χ2 = 8.86, P = 0.003), formation of an osseous bridge at the intervertebral space adjacent to ALs caused by the ossification of the anterior longitudinal ligament (38% vs. 86%, χ2 = 25.91, P < 0.001), and an abnormal height of the affected intervertebral space were all significantly lower in occult ALs (9% vs. 84%, χ2 = 60.41, P < 0.001). CONCLUSIONS Occult ALs presented with more subtle radiographic changes. Occult ALs should not be neglected, especially in the case of extensive occult ALs, because the stability of the spine might be severely impaired by these lesions.
Adult ; Humans ; Kyphosis/diagnostic imaging* ; Magnetic Resonance Imaging ; Middle Aged ; Radiography ; Retrospective Studies ; Spine/diagnostic imaging* ; Spondylitis, Ankylosing/diagnostic imaging*

BACKGROUNDAlthough previous reports had reported the use of temporary internal distraction as an aid to correct severe scoliosis, two-stage surgery strategy (less invasive internal distraction followed by posterior correction and instrumentation) has never been reported in the treatment of patients with severe spinal deformity. This study aimed to report the results of the surgical treatment of severe scoliosis and kyphoscoliosis by two-stage and analyse the safety and efficacy of this surgical strategy in the treatment of severe spinal deformities.

METHODSA total of 15 patients with severe scoliosis, kyphoscoliosis or kyphosis who underwent two-stage surgeries (less invasive internal distraction followed by posterior correction and instrumentation) were studied based on hospital records. Pretreatment radiographs and radiographs taken after first surgery (internal distraction by two small incisions), before second surgery (posterior correction, instrumentation and fusion), one week after second surgery and final follow-up were measured. Subjects were analyzed by age, gender, major coronal curve magnitude, flexibility of major curve, major sagittal curve magnitude before first surgery, after first surgery, before second surgery, after second surgery and at final follow-up. Complications related to two-stage surgeries were noted in each case.

RESULTSThe average major curve magnitude was 129.4° (range, 95° to 175°), reduced 58.9° or 45.4% after first stage surgery and reduced 30.6° or 24.6% after second stage surgery. The loss of correction during the interval between two surgeries was 7.1%. The total major coronal curve correction was 81.4° or 62.9%. At the final follow up, the average loss of correction of major coronal curve was 3.9° and the final average correction rate was 59.7%. The average major sagittal curve magnitude was 80.3° (range, 30° to 170°), and the total major sagittal curve correction was 48.2°. Loss of correction averaged 4.0° for major sagittal curve and the final correction averaged 42.2°. Clinical complications were noted in the peri-operative and long-term periods.

CONCLUSIONSTwo-stage surgery was a safe and effective surgical strategy in this difficult population. Using two-small-incision technique, the first stage surgery was less invasive. No permanent neurologic deficit was noted in this series.

Adolescent ; Child ; Female ; Humans ; Kyphosis ; diagnostic imaging ; surgery ; Male ; Radiography ; Scoliosis ; diagnostic imaging ; surgery ; Treatment Outcome

OBJECTIVE: To analyze the correlation between Cobb angle and spinous process angle (SPA) on X-ray film and body surface in patients with mild to moderate adolescent idiopathic scoliosis(AIS). To explore the possibility of linear SPA to assess scoliosis. METHODS: Retrospective study for correlation of Cobb angle and linear SPA on X-ray film. AIS patients treated and taken full spine anteroposterior X-ray from January 2019 to December 2021 were analyzed correlation of Cobb angle and linear SPA on X-ray film. Prospective study for correlation of Cobb angle and body linear SPA. AIS patients treated and taken full spine anteroposterior X-ray from December 1 to December 9 this year were analyzed correlation of Cobb angle and body linear SPA. RESULTS: A total of 113 AIS patients with age an average of (14.02±2.16) years old(ranged from 10 to 18 years old) were recruited in retrospective study, involving 26 males and 87 females;there were 71 patients with mild AIS and 42 patients with moderate AIS. Cobb angle in AIS patients was significantly inversely associated with SPA(r=-0.564, P<0.001), the linear regression equation was:Cobb angle=169.444-0.878×SPA. Cobb angles in patients with mild scoliosis were significantly and inversely associated with SPA(r=-0.269, P=0.012), the linear regression equation was:Cobb angle=46.832-0.185×SPA. Cobb angles in patients with moderate scoliosis were also clearly correlated with SPA(r=-0.417, P=0.003), the linear regression equation was:Cobb angle=113.889-0.516×SPA. Thirty-eight patients were recruited in prospective study. The mean Cobb angle and body linear SPA were(18.70±6.98)°, ranged from 11.3° to 36.0° and (170.34±4.57)°, ranged from 162.1° to 177.7° respectively. There was significantly negative correlation(r=-0.651, P<0.001), the linear regression equation is:Cobb angle=187.91-0.99×SPA. CONCLUSION Linear SPA on X-ray film or on the body was significantly negatively correlated with Cobb angles, but the regression equation fits poorly, so it's not suitable for diagnosis of scoliosis;however, linear SPA is appropriate for self-controlled assessment of scoliotic therapy or for dynamic assessment of spinal flexibility.
Male ; Female ; Humans ; Adolescent ; Child ; Scoliosis/diagnostic imaging* ; Prospective Studies ; Retrospective Studies ; Spine/diagnostic imaging* ; Kyphosis

OBJECTIVE: To explore the normal distribution of cervical sagittal alignment and the relationship between cervical alignment and global spine balance in asymptomatic young adults. METHODS: A cohort of 272 asymptomatic Chinese adults (including 161 males and 111 females, with an average age of (23.2±4.4) years, ranging from 18 to 45 years) were prospectively recruited from November 2011 to December 2014. The C₀-C₂ angle, disk angles from C₂-C₃ to C₆-C₇, vertebral angles from C₃ to C₇, T₁ slope, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), C₂-C₇ sagittal vertical axis (C₂-C₇SVA), center of gravity of head to C₇SVA (CGH-C₇SVA), C₇-S₁SVA were measured and statistically analyzed. All the subjects were categorized with the Roussouly classification and the cervical morphologies were evaluated as lordotic, straight, sigmoid or kyphotic. Spinal sagittal alignment parameters were compared between different sexes and Roussouly classifications with independent student t test, analysis of variance (ANOVA) or Chi-square test. Correlations between cervical sagittal alignment and global spine sagittal alignment were calculated using the Pearson and Spearman correlation coefficient. Linear regression analysis was performed. RESULTS: Sixty-seven males and 59 females aged from 18 to 30 years old were included in the study. The mean value of C₀-C₇ was 26.0°±12.8°, composed of 15.2°±6.7° for C₀-C₂, 9.1°±12.1° for sum of disk angles from C₂-C₃ to C₆-C₇, and 1.4°±10.2° for sum of vertebral angles from C₃ to C₇. C₂-C₇SVA [(18.6±7.9) mm] and CGH-C₇SVA [(22.9±12.3) mm]were offset ideally by C₇-S₁SVA [(-21.6±31.0) mm]. Males had a larger T₁ slope (P < 0.05) and accordingly, a larger cervical lordosis C₂-C₇ (P < 0.01) and C₀-C₇ angle (P < 0.01) than females. Males had a smaller C₇-S₁SVA (P < 0.01) and accordingly, a smaller CGH-C₇SVA (P=0.165) than females. Significant difference was found between cervical alignment of different Roussouly types (P < 0.01). In general, a larger LL was consistent with a set of larger TK, C₂-C₇angle, C₀-C₇ angle, and vice versa. There was no significant correlation between cervical morphology and the Roussouly classification (Chi-square=10.548, P=0.308). There was significant correlation between cervical alignment and T₁ slope (P < 0.01), TK (P < 0.01). There was significant correlation between adjacent segmental angles from T₁ slope up to C₀-C₂ angle (P < 0.05). CONCLUSION Normative values of each vertebral angle and disk angle were established. The cervical lordosis occurred mainly at C₀-C₂ and disk levels, which was influenced by parameters of other parts of the spine, such as T₁ slope, TK and the Roussouly classification. There was significant correlation between adjacent disk angles.
Adolescent ; Adult ; Cervical Vertebrae/diagnostic imaging* ; China ; Female ; Humans ; Kyphosis ; Lordosis/diagnostic imaging* ; Male ; Thoracic Vertebrae ; Young Adult

OBJECTIVE: To explore the correlation between the curvature of the cervical spine and the degree of cervical disc bulging in young patients with cervical pain. METHODS: The clinical data of 539 young patients with neck pain from January 2015 to December 2018 were retrospectively analyzed. There were 251 males and 288 females, aged 18 to 40 (32.2±6.3) years old. The cervical curvature and cervical disc bulging were measured by cervical X-ray and MRI. According to cervical curvature, the patients were divided into 175 cases of cervical lordosis group (cervical curvature > 7 mm), 163 cases of cervical erection group (0 kyphosis group (cervical curvature ≤ 0 mm). The degreeof cervical intervertebral disc bulging was compared among three groups, and the correlation between cervical curvature and cervical disc bulging was analyzed by Pearson correlation coefficient. RESULTS: The cervical disc bulging of cervical lordosis group, cervical erection group, and cervical kyphosis group were(0.83±0.24), (1.47±0.58), (2.96±1.11) mm, respectively. The degree of cervical disc bulging in cervical lordosis group was less than cervical erection group and cervical kyphosis group( CONCLUSION The degree of cervical disc bulging in young patients with neck pain is closely related to the reduction of cervical curvature.
Adolescent ; Adult ; Cervical Vertebrae/diagnostic imaging* ; Female ; Humans ; Kyphosis ; Lordosis ; Male ; Neck Pain/diagnostic imaging* ; Retrospective Studies ; Young Adult

OBJECTIVESTo evaluate the influence of thoracic kyphosis to sagittal alignment and balance of the lumbosacral vertebrae in thoracic adolescent idiopathic scoliosis patients.

METHODSStanding posteroanterior and lateral x-rays of a cohort of 55 patients with thoracic adolescent idiopathic scoliosis were obtained. The patients were classified according to their thoracic kyphosis, the first group TK < 10 degrees and the second group 10 degrees < or = TK < or = 40 degrees . The following parameters were measured: lumbar lordosis (LL), upper and lower arc of lumbar lordosis, sagittal vertical axis, sacral slope (SS), pelvic incidence (PI), pelvic tilt (PT). Sagittal plane parameters were analyzed using t-test between two groups, with significance set at P < 0.05. Linear correlations between parameters were calculated using Pearson correlation coefficients, with significance set at P < 0.01.

RESULTSThere were smaller LL and upper arc of lumbar lordosis in the first group. Significant linear correlations were found between each single adjacent shape parameter. Significant correlations were also found between TK, LL and upper arc of lumbar lordosis, as well as between PT, SS and PI.

CONCLUSIONSSagittal alignment and balance of the lumbosacral vertebrae may influence the thoracic kyphosis in AIS patients. The mechanism of this influence may through the adaptation of upper arc of lumbar lordosis. This influence must be considered in thoracic adolescent idiopathic scoliosis patients who undergo selective posterior thoracic fusion.

Adolescent ; Adult ; Female ; Humans ; Kyphosis ; complications ; pathology ; Lumbar Vertebrae ; diagnostic imaging ; pathology ; Male ; Radiography ; Sacrum ; diagnostic imaging ; pathology ; Scoliosis ; complications ; pathology ; Thoracic Vertebrae ; diagnostic imaging ; pathology

OBJECTIVE: To investigate the correlation between the changes of cervical curvature and atlantoaxial instability. METHODS: The correlation between the changes of cervical curvature and atlantoaxial instability was retrospectively studied in 50 outpatients with abnormal cervical curvature (abnormal cervical curvature group) from January 2018 to December 2019. There were 24 males and 26 females in abnormal cervical curvature group, aged from 18 to 42 years old with an average of(30.62±5.83) years. And 53 patients with normal cervical curvature (normal cervical curvature group) during the same period were matched, including 23 males and 30 females, aged from 21 to 44 years with an average of(31.98±6.11) years. Cervical spine X-ray films of 103 patients were taken in lateral position and open mouth position. Cervical curvature and variance of bilateral lateral atlanto-dental space(VBLADS) were measured and recorded, Pearson correlation coefficient analysis was used to study the correlation between the changes of cervical curvature and atlantoaxial instability. RESULTS: Atlantoaxial joint instability accounted for 39.6%(21/53) in normal cervical curvature group and 84.0%(42/50) in abnormal cervical curvature group. There was significant difference between two groups(P<0.01). VBLADS in abnormal cervical curvature group was (1.79±1.01) mm, which was significantly higher than that in normal cervical curvature group(0.55±0.75) mm(P<0.01). Pearson correlation coefficient analysis showed that the size of cervical curvature was negatively correlated with VBLADS. CONCLUSION Cervical curvature straightening and inverse arch are the cause of atlantoaxial instability, the smaller the cervical curvature, the more serious the atlantoaxial instability.
Adolescent ; Adult ; Atlanto-Axial Joint/diagnostic imaging* ; Cervical Vertebrae/diagnostic imaging* ; Female ; Humans ; Joint Instability/diagnostic imaging* ; Kyphosis ; Male ; Radiography ; Retrospective Studies ; Young Adult

OBJECTIVETo explore the clinical effects of total vertebral column resection combined with anterior mesh cage support in treating severe congenital kyphoscoliosis.

METHODSFrom April 2008 to April 2012,21 patients with severe congenital kyphoscoliosis were treated with total vertebral column resection and internal fixation through posterior approach combined with anterior mesh cage support. There were 8 males and 13 females with an average age of 19.4 years old (ranged from 10 to 35). And 6 cases were thoracic segments deformity,13 cases were thoracolumbar segments and 2 cases were lumbar segments, of them, 2 cases were accompanied with Chairs deformity, 6 cases with diastematomyelia, 4 cases with syringomyelia,and 1 case with neurofibromatosis. According to the Frankel grade system, 3 cases were grade C, 5 cases grade D and 13 cases grade E. Blood loss, operative time, and perioperative complications were recorded. Coronal and sagittal Cobb angle, apical vertebral offset distance, sagittal offset, the relative height of shoulders, razor back deformities were measured and analyzed before and after operation.

RESULTSThe average operative time was 5.2 h (3.5 to 6.5 h) and blood loss was 2,500 ml (1,400 to 4,900 ml). The 2nd day after operation, apical vertebral offset distance, sagittal offset, the relative height of shoulders, razor back deformities had obviously improved than preoperative (P < 0.05). There was no significant difference in above items between postoperative on the 2nd day and final follow-up (P > 0.05). The corrective rate of kyphosis and scoliosis were (60.97 +/- 6.30)% and (62.24 +/- 5.82)%, respectively. On the first day after surgery,2 cases of Frankel grade E aggravated to grade D, and obtained recovery at 2 week after conservative treatment. And 1 case palinesthesia later,grade D aggravated to grade C and obtained recovery after revision surgery in time. One case complicated with permanent blindness of left eye, 1 case occurred injury of pleura and 2 cases had cerebrospinal fluid leak during operation. All patients were followed up from 9 to 31 months with an av- erage of 18.6 months. At final follow-up,all patients obtained bone union, Frankel grade D in 4 cases and grade E in 17 cases, no correction loss and internal fixation loosening was found.

CONCLUSIONTotal vertebral column resection combined with anterior mesh cage support can effectively correct kyphosis and scoliosis in severe congenital kyphoscoliosis and can avoid injury of spine cord by spinal crispation, but intraoperative position and neurologic complications should still be considered.

Adolescent ; Adult ; Child ; Female ; Humans ; Kyphosis ; complications ; congenital ; diagnostic imaging ; surgery ; Male ; Retrospective Studies ; Scoliosis ; complications ; congenital ; diagnostic imaging ; surgery ; Spine ; surgery ; Tomography, X-Ray Computed ; Young Adult

OBJECTIVE: To explore the effects of morphological changes such as vertebral wedge deformation and disc degeneration (collapse) on adult thoracolumbar/lumbar degenerative kyphosis(TL/LDK) deformity. METHODS: A retrospective analysis of 32 patients with spinal TL/LDK deformity admitted from August 2015 to December 2020, including 8 males and 24 females, aged 48 to 75(60.3±12.4) years old. On the long-cassette standing upright lateral radiographs, the coronal Cobb angle, sagittal thoracic lumbar/lumbar kyphosis angle(KA) of spine were measured, and the height and wedge parameters of apex vertebral(AV) and two vertebrae(AV-1, AV-2, AV+1, AV+2) above and below AV and the intervertebrae and the intervertebral disc(AV-1D, AV-2D, AV+1D, AV+2D) were evaluated, involving anterior vertebral body height(AVH), posterior vertebral body height(PVH), vertebral wedge angle(VWA), ratio of vertebral wedging(RVW), anterior disc height(ADH), posterior disc height(PDH), disc wedge angle(DWA), ratio of disc wedging(RDW), and DWA/KA. RESULTS: The average angle of kyphosis was (44.2±19.1)°. A significant decrease in anterior height of vertebral was observed compared to the posterior height of vertebral(P<0.005). There was no significant difference in anterior and posterior height of discs. The vertebral wedging ratio/contribution ratio:AV-2(14.98±10.95)%/(14.21±8.08)%, AV-1(21.08±12.39)%/(18.09±7.38)%, AV(26.94±11.94)%/(25.52±8.64)%, AV+1(24.19±8.42)%/(20.82±8.69)%, AV+2(20.56±7.80)%/(15.60±9.71)%, total contribution(94.23±22.25)%, the disc wedging ratio/contribution ratio:AV-2D(2.88±2.57)%/(5.27±4.11)%, AV-1D(1.98±1.41)%/(2.29±2.16)%, AV+1D(-5.54±3.75)%/(-0.57±0.46)%, AV+2D(-8.27±4.62)%/(-1.22±1.11)%, total contribution (5.77±4.79)%. And the contribution rate of AV was significantly higher than that of adjacent vertebral(P<0.05). CONCLUSION The vertebral body and intervertebral disc shape both have influence on thoracolumbar kyphosis. However, the contribution of vertebral morphometry to the angle of TL/LDK deformity is relatively more important than the disc. The contribution of the wedge change of the AV to the TL/LDK deformity is particularly significant.
Male ; Adult ; Female ; Humans ; Middle Aged ; Aged ; Retrospective Studies ; Thoracic Vertebrae/diagnostic imaging* ; Lumbar Vertebrae/diagnostic imaging* ; Kyphosis ; Scoliosis ; Intervertebral Disc

OBJECTIVETo explore the feasibility of using transpedicular balloon kyphoplasty for aged osteoporotic thoracolumbar burst fractures with an in vitro model.

METHODSSimulated osteoporotic thoracolumbar burst fractures were created in 11 vertebral bodies. The burst fractures without obvious canal occupation were confirmed by spiral CT before the procedure. This operation involved the percutaneous insertion of two inflatable bone tamps into a fractured vertebral body transpedicularly under fluoroscopic guidance. Inflation of the bone tamp elevated the endplates, restored the vertebral body height, while created a cavity to be filled with bone cement. Preoperative and postoperative heights were measured, preoperative and postoperative sagittal diameter of vertebral canals were measured, and the repaired vertebral bodies were compressed to determine strength and stiffness values. The cement distribution and extravasation was evaluated by spiral CT after the procedure.

RESULTSThe transpedicular balloon kyphoplasty resulted in the significant restoration of the vertebral body height. The mean vertebral body heights was (20.73 +/- 1.37) mm before operation and (24.82 +/- 1.61) mm after operation (P < 0.01). Preoperative and postoperative sagittal diameter of vertebral canals were similar (P > 0.05). The cement distribution was regular, and the extravasation into spinal cannula was found in one case. The preoperative strength was significantly larger than the postoperative strength, whereas the postoperative stiffness was significantly less than the preoperative stiffness (P < 0.05).

CONCLUSIONSTranspedicular balloon kyphoplasty is an effective way to treat aged osteoporotic thoracolumbar burst fractures without obvious canal occupations and neurologic deficit in vitro. The procedure can increase strength and restore height of aged osteoporotic thoracolumbar burst fractures. Cement distribution and vertebral canal stenosis can be avoided.

Cadaver ; Humans ; Kyphoplasty ; instrumentation ; methods ; Kyphosis ; diagnostic imaging ; etiology ; surgery ; Osteoporosis ; complications ; Spinal Fractures ; complications ; diagnostic imaging ; surgery ; Spinal Fusion ; methods ; Thoracic Vertebrae ; pathology ; surgery ; Tomography, X-Ray Computed