首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.

Background Context

Proximal junctional kyphosis (PJK) is a challenging complication after rigid posterior instrumentation (RI) of the spine. Several risk factors have been described in literature so far, including the rigidity of the cranial aspect of the implant.

Purpose

The aim of this biomechanical study was to compare different proximal implants designed to gradually reduce the stiffness between the instrumented and non-instrumented spine.

Study Design/Setting

This is a biomechanical study.

Methods

Eight calf lumbar spines (L2–L6) underwent RI with a titanium pedicle screw rod construct at L4–L6. The proximal transition segment (L3–L4) was instrumented stepwise with different supplementary implants—spinal bands (SB), cerclage wires (CW), hybrid rods (HR), hinged pedicle screws (HPS), or lamina hooks (LH)—and compared with an all-pedicle screw construct (APS). The flexibility of each segment (L2–L6) was tested with pure moments of ±10.0?Nm in the native state and for each implant at L3–L4, and the segmental range of motion (ROM) was evaluated.

Results

On flexion and extension, the native uninstrumented L3–L4 segment showed a mean ROM of 7.3°. The CW reduced the mean ROM to 42.5%, SB to 41.1%, HR to 13.7%, HPS to 12.3%, LH to 6.8%, and APS to 12.3%. On lateral bending, the native segment L3–L4 showed a mean ROM of 15°. The CW reduced the mean ROM to 58.0%, SB to 78.0%, HR to 6.7%, HPS to 6.7%, LH to 10.0%, and APS to 3.3%. On axial rotation, the uninstrumented L3–L4 segment showed a mean ROM of 2.7°. The CW reduced the mean ROM to 55.6%, SB to 77.8%, HR to 55.6%, HPS to 55.6%, LH to 29.6%, and APS to 37.0%.

Conclusions

Using CW or SB at the proximal transition segment of a long RI reduced rigidity by about 60% in relation to flexion and extension in that segment, whereas the other implants tested had a high degree of rigidity comparable with APS. Clinical randomized controlled trials are needed to elucidate whether this strategy might be effective for preventing PJK.  相似文献   

2.

Background Context

Adult spinal deformity correction sometimes involves long posterior pedicle screw constructs extending from the lumbosacral spine to the thoracic vertebra. As fusion obliterates motion and places supraphysiological stress on adjacent spinal segments, it is crucial to ascertain the ideal upper instrumented vertebra (UIV) to minimize risk of proximal junctional failure (PJF). The T10 vertebra is often chosen to allow bridging of the thoracolumbar junction into the immobile thoracic vertebrae on the basis that it is the lowest immobile thoracic vertebra strut by the rib cage.

Purpose

This study aimed to characterize the range of motion (ROM) of each vertebral segment from T7 to S1 to determine if T10 is truly the lowest immobile thoracic vertebra.

Study Design/Setting

This is a prospective, comparative study.

Patient Sample

Seventy-nine adults (mean age of 45.4 years) presenting with low back pain or lower limb radiculopathy or both, without previous spinal intervention, metastases, fractures, infection, or congenital deformities of the spine, were included in the study.

Outcome Measures

A ROM >5° across two vertebral segments as determined by the Cobb method from radiographs.

Methods

Lumbar flexion-extension and neutral erect radiographs were obtained in randomized order using a slot scanner. Segmental ROM was measured from T7–T8 to L5–S1 and analyzed for significant differences using t tests. Age, gender, radiographical indices such as standard spinopelvic parameters, sagittal vertical axis (SVA), C7–T12 SVA, T1 slope, thoracic kyphosis (TK), and lumbar lordosis (LL) were studied via multivariate analysis to identify predictive factors for >5° change in ROM at the various segmental levels. There were no sources of funding and no conflicts of interest associated with this study.

Results

In the thoracolumbar spine, significant decreases in ROM when compared with the adjacent caudad segment occurs up to T9–T10, with mean total ROM of 1.98±1.47° (p<.001) seen in T9–T10, 2.19±1.67° (p<.001) in T10–T11, and 3.92±3.21°(p<.001) in T11–T12. The total ROM of T8–T9 (2.53±1.79°) was not significantly different from that of T9–T10 (p=.261). At the thoracolumbar junction, absence of scoliosis (OR 11.37, p=.020), high pelvic incidence (OR 1.14, p=.046), and low T1 slope (OR 1.45, p=.030) were predictive of ROM >5°.

Conclusions

Lumbar spine flexion-extension ROM decreases as it approaches the thoracolumbar junction. T10 is indeed the lowest immobile thoracic vertebra strut by the rib cage, and the last significant decrease in ROM is observed at T9–T10, in relation to T10–T11. However, because this also implies that a UIV of T10 would mean there is only one level of fixation above the relatively mobile segment, while respecting other factors that influence UIV selection, we propose the T9 vertebra as a more ideal UIV to fulfill the biomechanical concept of bridge fixation. However, this decision should still be taken on a case-by-case basis.  相似文献   

3.

Background Context

Total lumbar disc replacement (TDR) intends to avoid fusion-related negative side effects by means of motion preservation. Despite their widespread use, the adequate quality and quantity of motion, as well as the correlation between radiographic data with the patient's clinical symptomatology, remains to be established. Long-term data are lacking in particular.

Purpose

This study aimed to perform a clinical and radiographic long-term investigation following TDR with special emphasis on motion preservation assessment and to establish any potential correlation with patient-reported outcome parameters.

Study Design/Setting

A prospective, single-center, clinical, and radiological investigation following TDR with ProDisc II (Synthes, Paoli, PA, USA) was carried out.

Patient Sample

Patients with a minimum 5-year follow-up (FU) after TDR performed for the treatment of intractable and predominant (≥80%) axial low back pain resulting from single-level degenerative disc disease without instabilities or deformities at the lumbosacral junction (L5–S1) comprised the sample.

Outcome Measures

Visual analogue scale (VAS), Oswestry Disability Index (ODI), and patient satisfaction rates (three-scale outcome rating), range of motion (ROM) at the index- and cranially adjacent level as well as segmental lumbar lordosis (SLL) and global lumbar lordosis (GLL) were the outcome measures.

Methods

All data were acquired within the framework of an ongoing prospective clinical trial. Patients were examined preoperatively, 3, 6, and 12 months postoperatively, and annually thereafter. X-rays were performed in antero-posterior and lateral views as well as functional flexion/extension images. Radiological examinations included ROM at the index and cranially adjacent level as well as SLL and GLL. X-ray measurements were correlated with the clinical outcome parameters. A longitudinal analysis was performed between baseline data with those from the early (3–6 months), mid- (12–24 months), and late FU stages (≥5 years).

Results

Results from 51 patients with a mean FU of 7.8 years (range 5.0–13.3 years) were available for the final analysis. X-ray measurements revealed a maintained mobility with a trend toward gradually declining ROM values. Although no statistically significant difference in ROM was detected between the preoperative and early FU (6.8° vs. 5.8°, p=.1), a further reduction in ROM became statistically significant at the mid- and final FU, with mean ROM of 5.2° and 4.4°, respectively (p<.001).Global lumbar lordosis increased from 48.8° to 54.4° (p<.0001) which was attributed to a lordotic shift from 18.2° to 28.0° at the index segment (p<.00001) and which was positively correlated with the applied implant lordosis (p<.05). A compensatory reduction of lordosis was observed at the cranially adjacent segment (p<.0001). The mobility of the cranially adjacent level remained unchanged (p>.05).The clinical outcome scores (VAS, ODI) revealed a significant improvement from baseline levels (p<.05). The reduction in ROM was not negatively correlated with the patient's clinical symptomatology (p>.05).

Conclusion

The present data reveal an increased GLL resulting from a lordotic shift of the index segment, which was strongly correlated with the applied implant lordosis. This lordotic shift was accompanied by a compensatory reduction of lordosis at the cranially adjacent segment.A gradual and statistically significant decline of the device mobility was noted over time which, however, did not negatively impact the patient's clinical symptomatology.Although the present long-term investigation provides additional insight into longitudinal radiographic changes and their influence on the patient's clinical symptomatology following TDR, the adequate quality and quantity of motion with artificial motion-preserving implants remains to be established, which will aid in defining more refined treatment concepts for both fusion and motion preserving techniques alike.  相似文献   

4.

Background Context

Research shows the progression of ossification of the posterior longitudinal ligament (OPLL) following decompressive surgery for cervical myelopathy, particularly in cases presenting with continuous or mixed radiographic types. To date, no study has investigated OPLL progression within each motion segment.

Purpose

To evaluate progression of cervical OPLL in each motion segment using a novel system of classification, and to identify risk factors for OPLL progression following laminoplasty.

Study Design/Setting

Retrospective case series.

Patient Sample

This study included 34 patients (86 segments) with cervical myelopathy secondary to OPLL.

Outcome Measures

Clinical and radiological data (plain radiographs and computed tomography [CT]) were obtained.

Methods

Clinical data from 34 patients (86 segments) with cervical myelopathy secondary to OPLL were evaluated retrospectively. All subjects had undergone laminoplasty at a single center. Sagittal reconstructive CT images were used to measure OPLL thickness in each segment. Ossified masses were classified into four types according to the degree of disc space involvement: type 1 (no involvement); type 2 (involving disc space but not crossing); type 3 (crossing disc space but not fused); and type 4 (complete bridging). Range of motion (ROM) for each segment was measured using dynamic radiographs. Statistical analyses were performed to determine the degree of OPLL progression according to the four disc space involvement types and ROM.

Results

Mean OPLL progression was significantly higher in types 2 (1.3?mm) and 3 (1.5?mm) than in type 1 (0.5?mm) (p<.001). Severe progression (change in thickness >2?mm) was more frequent in types 2 (8 of 29) and 3 (7 of 16) than in types 1 (1 of 35) or 4 (0 of 6) (p=.002). In types 2 or 3, ROM>5° was correlated with severe OPLL progression (52% vs. 8%; p=.035).

Conclusions

Type 2 or 3 disc involvement and segmental ROM>5° were risk factors for OPLL progression. Classification of cervical OPLL according to disc involvement may help predict OPLL progression following laminoplasty. Close follow-up is warranted in cases of type 2 or 3 with greater segmental motion.  相似文献   

5.

Background Context

Anti-directional cervical joint motion has previously been demonstrated. However, quantitative studies of anti-directional and pro-directional cervical flexion and extension motions have not been published.

Purpose

This study aimed for a quantitative assessment of directional and anti-directional cervical joint motion in healthy subjects.

Study Design

An observational study was carried out.

Patients Sample

Eighteen healthy subjects comprised the study sample.

Outcome Measures

Anti-directional and pro-directional cervical flexion and extension motion from each cervical joint in degrees were the outcome measures.

Methods

Fluoroscopy videos of cervical flexion and extension motions (from neutral to end-range) were acquired from 18 healthy subjects. The videos were divided into 10% epochs of C0/C7 range of motion (ROM). The pro-directional and anti-directional motions in each 10% epoch were extracted, and the ratios of anti-directional motions with respect to the pro-directional motions (0%=no anti-directional movement) were calculated for joints and 10% epochs.

Results

The flexion and extension ROM for C0/C7 were 51.9°±9.3° and 57.2°±12.2°. The anti-directional motions of flexion and extension ROM constituted 42.8%±9.7% and 41.2%±8.2% of the respective pro-directional movements. For flexion, the first three joints (C0/C1, C1/C2, C2/C3) demonstrated larger ratios compared with the last three joints (C4/C5, C5/C6, C6/C7) (p<.03). For extension, C1/C2 and C2/C3 ratios were larger compared with C0/C1, C4/C5, and C5/C6 (p<.03). Comparisons between flexion and extension motions showed larger C0/C1 ratio but smaller C5/C6 and C6/C7 ratios in extension (p<.05).

Conclusions

This is the first report of quantified anti-directional cervical flexion and extension motion. The anti-directional motion is approximately 40% of the pro-directional motion. The results document that large proportions of anti-directional cervical flexion and extension motions were normal.  相似文献   

6.

Background Context

Flexion radiographs have been used to identify cases of spinal instability. However, current methods are not standardized and are not sufficiently sensitive or specific to identify instability.

Purpose

This study aimed to introduce a new slump sitting method for performing lumbar spine flexion radiographs and comparison of the angular range of motions (ROMs) and displacements between the conventional method and this new method.

Study Design

This study used is a prospective study on radiological evaluation of the lumbar spine flexion ROMs and displacements using dynamic radiographs.

Patient Sample

Sixty patients were recruited from a single spine tertiary center.

Outcome Measure

Angular and displacement measurements of lumbar spine flexion were carried out.

Method

Participants were randomly allocated into two groups: those who did the new method first, followed by the conventional method versus those who did the conventional method first, followed by the new method. A comparison of the angular and displacement measurements of lumbar spine flexion between the conventional method and the new method was performed and tested for superiority and non-inferiority.

Results

The measurements of global lumbar angular ROM were, on average, 17.3° larger (p<.0001) using the new slump sitting method compared with the conventional method. They were most significant at the levels of L3–L4, L4–L5, and L5–S1 (p<.0001, p<.0001 and p=.001, respectively). There was no significant difference between both methods when measuring lumbar displacements (p=.814).

Conclusion

The new method of slump sitting dynamic radiograph was shown to be superior to the conventional method in measuring the angular ROM and non-inferior to the conventional method in the measurement of displacement.  相似文献   

7.

Background Context

Many pelvic fixation options exist for posterior spinal fusion of pediatric neuromuscular scoliosis, including standard iliac screws (SISs) or a more recently introduced S2-Alar (S2A) technique. However, little data exist comparing the clinical and radiographic outcomes of these techniques.

Purpose

This study aimed to dentify differences in clinical and radiographic outcomes for pediatric neuromuscular scoliosis patients treated with SIS or S2A pelvic fixation.

Study Design/Setting

This was a retrospective cohort study at a pediatric orthopedic clinic.

Patient Sample

Patients aged 8–19 years undergoing posterior spinal fusion to the pelvis for neuromuscular scoliosis using SIS or S2A technique, with Gross Motor Function Classification System (GMFCS) Level 4 or 5 were included.

Outcomes Measures

Postoperative complication rates associated with pelvic fixation method were the outcome measures.

Methods

Charts and radiographs were reviewed for demographics, intra- and postoperative course, levels of instrumentation, operative correction, and implant failure (IF). Postoperative complications were classified according to the Accordion scale.

Results

We studied 50 patients (28 SIS, 22 S2A) aged 14.0±2.8 years and an average follow-up of 3.5±1.7 years. The average number of levels fused was 16.5±1.1 with an average curve correction of 48°±21° postoperatively. A significant difference in radiographic IF rates was noted between SIS and S2A groups (57% vs. 27%, p=.02). No difference was noted between groups for frequency or severity of postoperative complications, inclusive of wound infections. Subgroup analysis demonstrated equivalent IF rates when comparing the S2A group with the SIS group with cross-links.

Conclusions

The S2A group generally demonstrated improved rates of radiographic IF compared with the SIS group, but the rates became equivalent when a cross-link was added to an SIS construct. Further, no difference in postoperative complication rates were identified between SIS and S2A groups.  相似文献   

8.

Background

The long-term results of heterotopic ossification (HO) following lumbar total disc replacement (TDR) and the corresponding clinical and radiological outcomes are unclear.

Purpose

This study aimed to report the long-term results of HO following lumbar TDR and to analyze the clinical and radiological outcomes.

Study Design/Setting

A retrospective case review was performed for the consecutive patients who underwent lumbar TDR.

Patient Sample

The study included 48 patients (60 segments) who underwent lumbar TDR.

Outcome Measures

The time and location of HO development, segmental range of motion (ROM) of index level, the visual analog scale (VAS), and the Oswestry Disability Index (ODI) were analyzed.

Methods

Forty-eight patients (60 segments) were divided into HO and non-HO groups, and radiographs were used to measure the time and location of HO development. We compared segmental ROM between two groups using flexion-extension radiographs. Clinical outcomes were assessed using the VAS and the ODI. Furthermore, the segmental ROM, VAS, and ODI scores of each HO class were compared with those of the non-HO group.

Results

The mean follow-up duration was 104.4 months. Heterotopic ossification was detected in 30 of 60 segments following lumbar TDR, and HO progression was noted in six segments. The mean segmental ROM was significantly lower in the HO group than in the non-HO group. The mean VAS and ODI scores were not significantly different between the two groups. Segmental ROM was significantly lower in the class III and IV of the HO group than in the non-HO group. The VAS and ODI scores were not significantly different among the different classes.

Conclusions

We found that the incidence of HO is the highest within 12 months after lumbar TDR, and the incidence might increase 5 years after surgery. Furthermore, HO progressed over time. Segmental ROM was decreased in the HO groups; however, the limitation in motion might have little clinical influence.  相似文献   

9.

Background Context

There is significant variability in the materials commonly used for interbody cages in spine surgery. It is theorized that three-dimensional (3D)-printed interbody cages using porous titanium material can provide more consistent bone ingrowth and biological fixation.

Purpose

The purpose of this study was to provide an evidence-based approach to decision-making regarding interbody materials for spinal fusion.

Study Design

A comparative animal study was performed.

Methods

A skeletally mature ovine lumbar fusion model was used for this study. Interbody fusions were performed at L2–L3 and L4–L5 in 27 mature sheep using three different interbody cages (ie, polyetheretherketone [PEEK], plasma sprayed porous titanium-coated PEEK [PSP], and 3D-printed porous titanium alloy cage [PTA]). Non-destructive kinematic testing was performed in the three primary directions of motion. The specimens were then analyzed using micro-computed tomography (µ-CT); quantitative measures of the bony fusion were performed. Histomorphometric analyses were also performed in the sagittal plane through the interbody device. Outcome parameters were compared between cage designs and time points.

Results

Flexion-extension range of motion (ROM) was statistically reduced for the PTA group compared with the PEEK cages at 16 weeks (p-value=.02). Only the PTA cages demonstrated a statistically significant decrease in ROM and increase in stiffness across all three loading directions between the 8-week and 16-week sacrifice time points (p-value≤.01). Micro-CT data demonstrated significantly greater total bone volume within the graft window for the PTA cages at both 8 weeks and 16 weeks compared with the PEEK cages (p-value<.01).

Conclusions

A direct comparison of interbody implants demonstrates significant and measurable differences in biomechanical, µ-CT, and histologic performance in an ovine model. The 3D-printed porous titanium interbody cage resulted in statistically significant reductions in ROM, increases in the bone ingrowth profile, as well as average construct stiffness compared with PEEK and PSP.  相似文献   

10.

Background context

Many studies tend to characterize cervical kyphosis as a significant clinical condition that needs to be treated. Moreover, opinions vary on whether cervical kyphosis should be considered a pathologic status or a natural occurrence in asymptomatic people.

Purpose

This study aimed to determine the frequency of kyphotic posture of the cervical spine in currently asymptomatic individuals and to ascertain its relation with other spinopelvic parameters.

Study Design

A cross-sectional radiographic study was carried out.

Patient Sample

This study targeted 1,026 currently asymptomatic adult volunteers who agreed to participate in this study from January 2010 to March 2016. Only 958 were eligible for the study.

Outcome Measures

Radiographic images, including the C-spine dynamic view and whole-spine lateral view, were measured. The sagittal parameters of the cervical spine and other parts of the spine and pelvis, such as the C2–C7 angle, C0–C2 range of motion (ROM), C2–C7 ROM, and C0–C7 ROM, thoracic kyphosis, lumbar lordosis, sacral slope, pelvic tilt, and pelvic incidence, were measured.

Methods

Based on the C-spine neutral lateral X-ray, a C2–C7 Cobb angle greater than 0 degree was defined as lordosis and an angle less than 0 degree was defined as kyphosis. Patients who showed kyphosis were further classified into the reducible or non-reducible group, depending on the ability of recovering neck motions (lordosis) in extension. The cervical and other global spine parameters between the two groups were analyzed, and the relation between the cervical alignment and other parts of the spine and pelvis were also examined. This study was not supported by any funding and had no conflicts of interest.

Results

Nearly one-fourth of the asymptomatic participants (26.3%) have kyphotic cervical posture, and almost one-sixth of the kyphotic individuals (16.7%) have non-reducible kyphosis. The prevalence increases with advanced age; non-reducible cases are mostly kyphotic, kyphosis stems from the C2–C7 region, and kyphosis is not correlated with any of the radiological parameters of the other parts of the spine except lumbar lordosis.

Conclusions

Cervical kyphosis can be observed in normal healthy adults.  相似文献   

11.

Background Context

Lumbar total disc replacement (TDR) operation represents an alternative to lumbar fusion for the treatment of symptomatic lumbar intervertebral disc degeneration and has gained increasing attention in recent years.

Purpose

This study aimed to assess clinical outcomes in a cohort of patients with TDR and the long-term survival rate of the prostheses.

Study Design

This is a retrospective, single-center clinical study.

Patient Sample

The sample comprised 30 patients, giving a total of 35 prostheses after an average follow-up (FU) of 15.2 years following TDR, which was performed for the treatment of lumbar degenerative disc disease.

Outcome Measures

Clinical evaluation included visual analog scale (VAS) and the Oswestry Disability Index (ODI). Radiological parameters of intervertebral disc height (IDH), range of motion (ROM), lumbar lordosis, lumbar scoliosis, and prosthesis position were evaluated in surgical and adjacent levels. Complications and re-operation rates were also assessed.

Methods

Clinical evaluation and radiological parameters were evaluated preoperatively and at final FU. All data were collected by members of our department, including research assistants and nurses who were not involved in the decision making of this study.

Results

Thirty of the 35 patients participated in the final FU. The cumulative survival rate of the prosthesis at a mean FU of 15.4 years was 100%. The clinical success rate was 93.3%. The VAS and ODI scores at final FU were significantly lower than preoperatively (p<.001). The average ROM of the operated and superior adjacent segment decreased significantly at the final FU, whereas the inferior adjacent segment was not affected. The IDH of all surgical and adjacent levels were well maintained at the final FU. Ten patients had a lumbar scoliosis >3° and the mean angle was 8.5°, of which 7 had left convex curvature. Three prostheses were offset more than 5?mm from the midline on the coronal plane. Four prostheses showed subsidence. Twenty-six operative segments and five adjacent segments showed heterotopic ossification. Two patients of the total 35-patient cohort underwent a secondary operation.

Conclusions

Satisfactory clinical results and good prosthesis survival can be achieved in the long term. Lumbar TDR surgeries also have the potential to reduce the incidence of adjacent segment disease.  相似文献   

12.

Background Context

Hybrid surgery (HS), consisting of cervical disc arthroplasty (CDA) at the mobile level, along with anterior cervical discectomy and fusion at the spondylotic level, could be a promising treatment for patients with multilevel cervical degenerative disc disease (DDD). An advantage of this technique is that it uses an optimal procedure according to the status of each level. However, information is lacking regarding the influence of the relative location of the replacement and the fusion segment in vivo.

Purpose

We conducted the present study to investigate whether the location of the fusion affected the behavior of the disc replacement and adjacent segments in HS in vivo.

Study Design

This is an observational study.

Patient Sample

The numbers of patients in the arthroplasty-fusion (AF) and fusion-arthroplasty (FA) groups were 51 and 24, respectively.

Outcome Measures

The Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analog Scale (VAS) scores were evaluated. Global and segmental lordosis, the range of motion (ROM) of C2–C7, and the operated and adjacent segments were measured. Fusion rate and radiological changes at adjacent levels were observed.

Methods

Between January 2010 and July 2016, 75 patients with cervical DDD at two contiguous levels undergoing a two-level HS were retrospectively reviewed. The patients were divided into AF and FA groups according to the locations of the disc replacement. Clinical outcomes were evaluated according to the JOA, NDI, and VAS scores. Radiological parameters, including global and segmental lordosis, the ROM of C2–C7, the operated and adjacent segments, and complications, were also evaluated.

Results

Although the JOA, NDI, and VAS scores were improved in both the AF and the FA groups, no significant differences were found between the two groups at any follow-up point. Both groups maintained cervical lordosis, but no difference was found between the groups. Segmental lordosis at the fusion segment was significantly improved postoperatively (p<.001), whereas it was maintained at the arthroplasty segment. The ROM of C2–C7 was significantly decreased in both groups postoperatively (AF p=.001, FA p=.014), but no difference was found between the groups. The FA group exhibited a non-significant improvement in ROM at the arthroplasty segment. The ROM adjacent to the arthroplasty segment was increased, although not significantly, whereas the ROM adjacent to the fusion segment was significantly improved after surgery in both groups (p<.001). Fusion was achieved in all patients. No significant difference in complications was found between the groups.

Conclusions

In HS, cephalic or caudal fusion segments to the arthroplasty segment did not affect the clinical outcomes and the behavior of CDA. However, the ROM of adjacent segments was affected by the location of the fusion segment; segments adjacent to fusion segments had greater ROMs than segments adjacent to arthroplasty segments.  相似文献   

13.

Background Context

Patients with adolescent idiopathic scoliosis (AIS) perform surprisingly well after spinal correction and fusion. It was previously hypothesized that, during gait, certain mechanisms compensate for the loss in spinal motion. Still, previous studies could not identify such compensatory mechanisms in the lower body.

Purpose

This study aims to test the hypothesis of a compensatory increased motion of the distal unfused part of the spine during gait after posterior spinal correction and fusion.

Study

This is a prospective gait study.

Patients and Methods

Twelve patients with AIS were included. Sets of three VICON skin markers were used to measure the 3D motion of the proximal part of the fusion in relation to the pelvis (PFP) and the distal part of the fusion in relation to the pelvis (DFP). By doing so, PFP represents the motion of the fused and unfused parts of the spine, and DFP represents the motion of the unfused part of the spine. Measurements were performed preoperatively and 3 and 12 months after posterior spinal correction and fusion.

Results

Surgery resulted in a decrease in PFP transversal plane range of motion (ROM) (8.3° vs. 5.9°, p=.006). No compensatory increase in the ROM of DFP could be identified. Actually, DFP transversal plane ROM also decreased (8.2° vs. 5.6°, p=.019). No improvement over time was observed when comparing the 3- and 12-month postoperative measurements.

Conclusions

The hypothesis of a compensatory increase in motion of the distal unfused segments after spinal fusion for AIS is a much researched and controversial topic. This study is the first to study this hypothesis in such detail during gait and could not demonstrate such increase.  相似文献   

14.

Background Context

Measurement of cervical spine range of motion (ROM) is often considered to be an essential component of cervical spine physiotherapy assessment.

Purpose

This study aimed to investigate the reliability and validity of an iPhone application (app) (Goniometer Pro) for measuring active craniocervical ROM (ACCROM) in patients with non-specific neck pain.

Study Design/Setting

A cross-sectional study was conducted at the musculoskeletal biomechanics laboratory located at Iran University of Medical Sciences.

Patient Sample

Forty non-specific neck pain patients participated in this study.

Outcome Measures

The outcome measure was the ACCROM, including flexion, extension, lateral flexion, and rotation.

Method

Following the recruitment process, ACCROM was measured using a universal goniometer (UG) and iPhone 7 app. Two blinded examiners each used the UG and iPhone to measure ACCROM in the following sequences: flexion, extension, lateral flexion, and rotation. The second (2?hours later) and third (48?hours later) sessions were carried out in the same manner as the first session. Intraclass correlation coefficient (ICC) models were used to determine the intra-rater and inter-rater reliability. The Pearson correlation coefficients were used to establish concurrent validity of the iPhone app. Minimum detectable change at the 95% confidence level (MDC95) was also computed.

Results

Good intra-rater and inter-rater reliability was demonstrated for the goniometer with ICC values of ≥0.66 and ≥0.70 and the iPhone app with ICC values of ≥0.62 and ≥0.65, respectively. The MDC95 ranged from 2.21° to 12.50° for the intra-rater analysis and from 3.40° to 12.61° for the inter-rater analysis. The concurrent validity between the two instruments was high, with r valuesof ≥0.63. The magnitude of the differences between the UG and iPhone app values (effect sizes) was small, with Cohen d values of ≤0.17.

Conclusions

The iPhone app possesses good reliability and high validity. It seems that this app can be used for measuring ACCROM.  相似文献   

15.

Background Context

Prolonged microgravity exposure is associated with localized low back pain and an elevated risk of post-flight disc herniation. Although the mechanisms by which microgravity impairs the spine are unclear, they should be foundational for developing in-flight countermeasures for maintaining astronaut spine health. Because human spine anatomy has adapted to upright posture on Earth, observations of how spaceflight affects the spine should also provide new and potentially important information on spine biomechanics that benefit the general population.

Purpose

This study compares quantitative measures of lumbar spine anatomy, health, and biomechanics in astronauts before and after 6 months of microgravity exposure on board the International Space Station (ISS).

Study Design

This is a prospective longitudinal study.

Sample

Six astronaut crewmember volunteers from the National Aeronautics and Space Administration (NASA) with 6-month missions aboard the ISS comprised our study sample.

Outcome Measures

For multifidus and erector spinae at L3–L4, measures include cross-sectional area (CSA), functional cross-sectional area (FCSA), and FCSA/CSA. Other measures include supine lumbar lordosis (L1–S1), active (standing) and passive (lying) flexion-extension range of motion (FE ROM) for each lumbar disc segment, disc water content from T2-weighted intensity, Pfirrmann grade, vertebral end plate pathology, and subject-reported incidence of chronic low back pain or disc injuries at 1-year follow-up.

Methods

3T magnetic resonance imaging and dynamic fluoroscopy of the lumbar spine were collected for each subject at two time points: approximately 30 days before launch (pre-flight) and 1 day following 6 months spaceflight on the ISS (post-flight). Outcome measures were compared between time points using paired t tests and regression analyses.

Results

Supine lumbar lordosis decreased (flattened) by an average of 11% (p=.019). Active FE ROM decreased for the middle three lumbar discs (L2–L3: ?22.1%, p=.049; L3–L4: ?17.3%, p=.016; L4–L5: ?30.3%, p=.004). By contrast, no significant passive FE ROM changes in these discs were observed (p>.05). Disc water content did not differ systematically from pre- to post-flight. Multifidus and erector spinae changed variably between subjects, with five of six subjects experiencing an average decrease 20% for FCSA and 8%–9% for CSA in both muscles. For all subjects, changes in multifidus FCSA strongly correlated with changes in lordosis (r2=0.86, p=.008) and active FE ROM at L4–L5 (r2=0.94, p=.007). Additionally, changes in multifidus FCSA/CSA correlated with changes in lordosis (r2=0.69, p=.03). Although multifidus-associated changes in lordosis and ROM were present among all subjects, only those with severe, pre-flight end plate irregularities (two of six subjects) had post-flight lumbar symptoms (including chronic low back pain or disc herniation).

Conclusions

We observed that multifidus atrophy, rather than intervertebral disc swelling, associated strongly with lumbar flattening and increased stiffness. Because these changes have been previously linked with detrimental spine biomechanics and pain in terrestrial populations, when combined with evidence of pre-flight vertebral end plate insufficiency, they may elevate injury risk for astronauts upon return to gravity loading. Our results also have implications for deconditioned spines on Earth. We anticipate that our results will inform new astronaut countermeasures that target the multifidus muscles, and research on the role of muscular stability in relation to chronic low back pain and disc injury.  相似文献   

16.

Background Context

Sagittal imbalance is associated with poor clinical outcomes in patients with degenerative lumbar disease. However, there is no consensus on the impact of posterior lumbar interbody fusion (PLIF) on local and global sagittal balance.

Purpose

To reveal the effect of one- or two-level PLIF on global sagittal balance.

Design/Setting

A retrospective case-control study.

Patients Sample

This study included 88 patients who underwent a one- or two-level PLIF for spinal stenosis with spondylolisthesis.

Outcome Measures

Clinical and radiological parameters were measured pre- and postoperatively.

Methods

All patients were followed up for >2 years. Clinical outcomes included a visual analog scale, Oswestry Disability Index, and EuroQol 5-dimension questionnaire (EQ-5D). Radiological parameters were measured using whole-spine standing lateral radiographs. Fusion, loosening, subsidence rates, and adverse events were also evaluated. Patients were divided into two groups according to their preoperative C7–S1 sagittal vertical axis (SVA): Group N: SVA≤5?cm vs Group I: SVA>5?cm; they were also divided according to postoperative changes in C7–S1 SVA. Clinical and radiological outcomes were compared between the groups.

Results

All clinical outcomes and radiological parameters improved postoperatively. C7–S1 SVA improved (?1.6?cm) after L3–L5 fusion, but it was compromised (+3.6?cm) after L4–S1 fusion (p=.001). Preoperative demographic and clinical data showed no difference except in the anxiety or depression domain of EQ-5D. No differences were found in postoperative clinical outcomes. Lumbar lordosis, pelvic tilt, and thoracic kyphosis slightly improved in Group N, whereas C7–S1 SVA decreased from 9.5?cm to 3.8?cm (p<.001) in Group I. Furthermore, all sagittal parameters improved in Group I. On comparing the postoperative changes in C7–S1 SVA, we found that the decreasing trend in the postoperative C7–S1 SVA was related to a larger preoperative C7–S1 SVA (p=.030) and a more proximal level fusion (L3–L5 vs L4–S1, p=.033).

Conclusions

Global sagittal balance improved after short-level lumbar fusion surgery in patients having spinal stenosis with spondylolisthesis who showed preoperative sagittal imbalance. Restoration of sagittal balance predominantly occurred after L3–L4, L4–L5, or L3–L5 PLIF. However, no such restoration was observed after L5–S1 or L4–S1 PLIF. Thus, we could anticipate sagittal balance restoration after performing PLIF at L3–L4 or L4–L5 level. However, caution is required when planning for L5–S1 fusion if preoperative sagittal imbalance is present.  相似文献   

17.

Background

Sagittal decompensation after pedicle subtraction osteotomy (PSO) is considered as late onset complication. Several mechanisms have been suggested, but little attention has been paid to the caudal end of lumbar instrumented fusion, especially sacral iliac joint (SIJ) deterioration.

Methods

Clinical histories and radiographic sagittal parameters of two patients with SIJ luxation after PSO are presented. The biomechanical failure mechanism and risk factors are analysed.

Results

Two patients underwent correction of fixed anterior sagittal imbalance by PSO, followed by pseudarthrosis revision surgery. Both of them sustained persistent sacroiliac pain, progressive recurrence of anterior imbalance and progressive pelvic incidence (PI) increase around 10°. An acute bilateral SIJ luxation occurred in both patients leading to sharp increase or PI around 20°. One patient was treated by SIJ fusion and the other patient was placed on non-weight-bearing crutch ambulation for 1 year. Both patients had a high preoperative PI (95° and 78°). A theoretical match between lumbar lordosis (LL) and PI was not achieved by PSO. Osteopenia was present in both patients. Computed tomography evidenced L5–S1 pseudarthrosis and sacroiliac joint violation by pelvic or sacral ala screws.

Conclusion

Patients with high PI might seek for further compensation at their SIJ when lacking LL after PSO. Chronic anterior imbalance might lead to progressive weakening of sacroiliac ligaments. Initial circumferential lumbosacral fusion and accurate iliac screw fixation might reduce stress on implants, risk for pseudarthrosis, implant failure and finally SIJ deterioration. Bone mineral density should further be investigated preoperatively.
  相似文献   

18.

Background Context

Gait patterns and their relationship to demographic and radiographic data in patients with adult spinal deformity (ASD) have not been fully documented.

Purpose

This study aimed to assess gait pattern in patients with ASD and the effect of corrective spinal surgery on gait.

Design/Setting

This is a prospective case series.

Patient Sample

The gait patterns of 33 consecutive women with ASD (age 67.1 years; body mass index [BMI] 22.5±2.5?kg/m2, Cobb angle 46.8±18.2°, coronal vertical axis [CVA] 1.5±3.7?cm, C7 sagittal vertical axis [SVA] 9.1±6.4?cm, pelvic incidence minus lumbar lordosis [PI?LL] 38.2±22.1°, and lean volume of the lower leg, 5.5±0.6?kg) before and after corrective surgery were compared with those of 33 age- and gender-matched healthy volunteers.

Outcome Measures

Scoliosis Research Society Patient Questionnaire (SRS22r), Oswestry Disability Index (ODI), and forceplate analysis.

Methods

All subjects underwent gait analysis on a custom-built forceplate using optical markers placed on all joints and spinal processes. Dual X-ray absorptiometry scores were used to calculate the lean composition of the lower legs. Subjects with ASD were followed for at least 2 years post operation.

Results

Preop mean values showed that patients with ASD had a significantly worse gait velocity (54±10?m/min vs. 70.7±12.9?m/min, p<.01) and stride (97.8±13.4?cm vs. 115.3±15.1?cm, p<.01), but no difference was observed in the stance-to-swing ratio. The right and left ground reaction force vectors were also discordant in the ASD group (vertical direction; r=0.84 vs. r=.97, p=.01). The hip range of motion (ROM) was also significantly decreased in ASD. Correlation coefficient showed moderate correlations between the preoperative gait velocity and the gravity line (GL), PI, ROM of the lower extremity joints, and lean volume, and between the stride and the lean volume, GL, and PI?LL. Gait pattern, stride, and velocity all improved significantly in the patients with ASD after surgery, but were still not as good as in healthy volunteers. The SRS22r satisfaction domain correlated moderately with postoperative gait velocity (r=0.34).

Conclusions

The patients with ASD had an asymmetric gait pattern and impaired gait ability compared with healthy volunteers. Gait ability correlated significantly with the GL, spinopelvic alignment, lower extremity joint ROM, and lean volume. The surgical correction of spinopelvic alignment and exercises to build muscle strength may improve the gait pattern and ability in patients with ASD.  相似文献   

19.

Background Context

Spinal metastases occur in 30%–50% of patients with systemic cancer. The primary goals of palliation are pain control and prevention of local recurrence.

Purpose

This study aimed to test the safety and efficacy of a combined modality approach consisting of kyphoplasty and intraoperative radiotherapy (Kypho-IORT).

Study Design/Setting

Kyphoplasty and intraoperative radiotherapy was a prospective, single-center phase I/II trial. Patients were enrolled in a classical 3+3 scheme within the initial phase I, where Kypho-IORT was applied using a needle-shaped 50?kV X-ray source at three radiation dose levels (8?Gy in 8-mm, 8?Gy in 11-mm, and 8?Gy in 13-mm depth). Thereafter, cohort expansion was performed as phase II of the trial. The trial is registered with clinicaltrials.gov, number NCT01280032.

Patient Sample

Patients aged 50 years and older with a Karnofsky Performance Status of at least 60% and with one to three painful vertebral metastases confined to the vertebral body were eligible to participate.

Outcome Measures

The primary end point was safety as per the occurrence of dose-limiting toxicities. The secondary end points were pain reduction, local progression-free survival (L-PFS), and overall survival (OS).

Methods

Pain was measured using the visual analog scale (VAS) and local control was assessed in serial computed tomography or magnetic resonance imaging scans.

Results

None of the nine patients enrolled in the phase I showed dose-limiting toxicities at any level and thus, 52 patients were subsequently enrolled into a phase II, where Kypho-IORT was performed at various dose levels. The median pain score significantly dropped from 5 preoperatively to 2 at the first postoperative day (p<.001). Of 43 patients who reported a pre-interventional pain level of 3 or more, 30 (69.8%) reported a reduction of ≥3 points on the first postoperative day. A persistent pain reduction beyond the first postoperative day of ≥3 points was seen in 34 (79.1%) patients. The 3, 6, and 12 month L-PFS was excellent with 97.5%, 93.8%, and 93.8%. The 3, 6, and 12 months OS was 76.9%, 64.0%, and 48.4%.

Conclusion

Kyphoplasty and intraoperative radiotherapy is safe and immediately provided sustained pain relief with excellent local control rates in patients with painful vertebral metastases.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号