Preclinical Evaluation of a Novel 3D-Printed Movable Lumbar Vertebral Complex for Replacement: In Vivo and Biomechanical Evaluation of Goat Model.

PURPOSE: This was an in vivo study to develop a novel movable lumbar artificial vertebral complex (MLVC) in a goat model. The purpose of this study was to evaluate clinical and biomechanical characteristics of MLVC and to provide preclinical data for a clinical trial in the future. METHODS: According to the preoperative X-ray and CT scan data of the lumbar vertebrae, 3D printing of a MLVC was designed and implanted in goats. The animals were randomly divided into three groups: intact, fusion, and nonfusion. In the intact group, only the lumbar vertebrae and intervertebral discs were exposed during surgery. Both the fusion and nonfusion groups underwent resection of the lumbar vertebral body and the adjacent intervertebral disc. Titanium cages and lateral plates were implanted in the fusion group. MLVC was implanted in the nonfusion group. All groups were evaluated by CT scan and micro-CT to observe the spinal fusion and tested using the mechanical tester at 6 months after operation. RESULTS: The imaging results showed that with the centrum, the artificial endplates of the titanium cage and MLVC formed compact bone trabeculae. In the in vitro biomechanical test, the average ROM of L3-4 and L4-5 for the nonfusion group was found to be similar to that of the intact group and significantly higher in comparison to that of the fusion group (P < 0.05). The average ROM of flexion, extension, lateral bending, and rotation in the L2-3 intervertebral space significantly increased in the fusion group compared with the intact group and the nonfusion group (P < 0.001). There were no significant differences in flexion, extension, lateral bending, and rotation between the nonfusion and intact groups (P > 0.05). The average ROM of flexion, extension, lateral bending, and rotation in the L2-5 intervertebral space was not significantly different between the intact group, the fusion group, and the nonfusion group, and there was no statistical significance (P > 0.05). HE staining results did not find any metal and polyethylene debris caused by abrasion. CONCLUSION: In vivo MLVC can not only reconstruct the height and stability of the centrum of the operative segment but also retain the movement of the corresponding segment.

Indications for Lumbar Fusion in the Skeletally Mature Adolescent: How to Address Oblique Takeoff and Limb Length Discrepancy.

BACKGROUND: Indications for posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI) of a scoliotic deformity in a skeletally mature individual are based on the balance between the anticipated benefit of stopping future curve progression and the potential downside of loss of spinal mobility. The dilemma regarding PSF with SSI in the adolescent population is exacerbated by the patient's participation in athletics requiring flexibility and motion of the spine, the location of the curve, the presence of pelvic obliquity, and the impact of a limb length discrepancy. The purpose of this review is to discuss the potential advantages and disadvantages of PSF with SSI in a hypothetical skeletally mature adolescent with a 45-degree lumbar curve, pelvic obliquity, and limb length discrepancy. DISCUSSION: Natural history studies of untreated adolescent idiopathic scoliosis (AIS) have shown that slow curve progression throughout adulthood is likely. Adults with untreated AIS may also have more back pain and dissatisfaction with their appearance. Although the clinical and radiographic outcomes of PSF with SSI are excellent, patients should be counseled about the impact of fusing the lumbar spine on back pain, decreased spinal mobility, and potential inability to return to athletics at the same level. Adults who undergo surgery for AIS have greater operative morbidity and number of levels fused compared with adolescents. CONCLUSION: These factors should be presented when discussing observation versus PSF with SSI with patients and families. Delaying surgery until formal athletic participation is complete should be considered.

Comparison between anteroposterior and oblique "Scotty dog" approach during S1 transforaminal epidural steroid injection: A randomized controlled trial.

BACKGROUND: Traditionally, S1 transforaminal epidural steroid injection (TFESI) has been performed using an anteroposterior (AP) fluoroscopic view. In 2007, the oblique "Scotty dog" (OS) approach was introduced as an alternative technique. We compared passage time of the needle into S1 foramen (Tf) between the anteroposterior (AP) and oblique "Scotty dog" (OS) approach during S1 TFESI. METHODS: In this prospective randomized controlled trial, seventy patients scheduled S1 TFESI were randomly allocated into AP or OS groups. In the AP group, a slight cephalad-caudad tilt was used. In the OS group, the C-arm was rotated ipsilateral oblique degrees to view the S1 Scotty dog. Both groups received injection of steroid mixed with local anesthetics. We measured the passage time of the needle into S1 foramen (Tf), primary outcome, and total procedure time (Tt) between the groups. We also recorded presence of intravascular injection, patients-assessed pain relief for one month and complications. RESULTS: The Tf and Tt were shorter in the OS than in the AP group (24.4 ±â€Š24.0 s vs 47. 8 ±â€Š53.2seconds; 93.3 ±â€Š35.0 seconds vs 160.0 ±â€Š98.7 seconds, P < .001, both). Incidence of intravascular injection (AP, 8 [22.8%]; OS, 4 [11.4%], P = .205), pain score, and complication rates were not statistically different between the two groups. In logistic regression analysis, the body mass index (BMI) was a risk factor for longer Tt (odds ratio [OR] = 1.27, 95% CI: 1.02-1.58, P = .030). CONCLUSION: The passage time of the needle into S1 foramen was shorter in OS approach and the OS approach reduced the procedure time compared with the AP approach during S1 TFESI. The practitioners should note that procedure time can be prolonged in obese patients.

Compensatory Mechanism of Maintaining the Sagittal Balance in Degenerative Lumbar Scoliosis Patients with Different Pelvic Incidence.

OBJECTIVE: To investigate the compensatory mechanism of maintaining the sagittal balance in degenerative lumbar scoliosis patients with different pelvic incidence (PI). METHODS: This was a retrospective imaging observation study. Patients in our department with degenerative lumbar scoliosis between 2017 and 2019 were reviewed. A total of 36 patients were eligible and included in the present study. The average age of those patients was 64.22 years, including 8 men and 28 women. The coronal and sagittal parameters were measured on full-length spine X-ray film, including globe kyphosis (GK), lumber lordosis (LL), thoracolumbar kyphosis (TLK), thoracic kyphosis (TK), sagittal vertical axis (SVA), sagittal shift angle, Cobb angle, coronal shift angle, and vertebra. The anterior pelvic plane angle (APPA) and pelvic parameters were also measured, including the pelvic tilt (PT), the PI, and the sacral slope (SS). PI-LL, LL-SS, and GK-SS were calculated. Traditional pelvic tilt was also calculated using the following formula: cPT = PI × 0.37-7. These patients were divided into two groups according to their PI values. The patients' PI value in Group 1 was smaller than 50°. The patients' PI value in Group 2 was equal to or larger than 50°. RESULTS: These patients' SS, PT, PI, LL, TLK, TK, and GK were 28.70° ± 11.36°, 23.28° ± 6.55°, 52.00° ± 11.03°, 31.66° ± 14.12°, 12.12° ± 14.9°, 17.81° ± 13.53°, and -13.17° ± 16.27°. The sagittal shift angle, the APPA, the Cobb angle, the coronal shift angle, vertebra, PI-LL, cPT, APPA-4, LL-SS, and GK-SS were 4.38° ± 5.75°, -12.55° ± 8.83°, 30.03° ± 12.59°, 2.40° ± 2.13°, 4.08 ± 0.93, 19.86° ± 10.97°, 12.35° ± 4.55°, -8.30° ± 9.07°, 3.30° ± 8.82°, and 15.53° ± 9.83°, respectively. There was no significant difference between PT and cPT + APPA-4 or between cPT and PT-APPA+4. There was significant difference between PT and cPT + APPA or between cPT and PT-APPA. This demonstrated that the APPA-4 is reliable as degree of the pelvic sagittal retroversion. There were significant differences in SS, PI, LL, TLK, GK, APPA, PT-APPA, PT-APPA+4, cPT, and APPA-4 between Group 1 and Group 2. There were no significant differences in PT, TK, sagittal shift angle, SVA, Cobb angle, coronal shift angle, vertebra number, PI-LL, cPT + APPA, cPT + APPA-4, LL-SS, and GK-SS between Group 1 and Group 2. The Pearson tests showed that PI-LL had significant correlations with TK, LL, sagittal shift angle, SVA, and LL-SS. There was no significant correlation between PI-LL and Cobb angle, GK, TLK, APPA, vertebra, Coronal Shift Angle, or GK-SS. CONCLUSION: The APPA-4 is reliable as degree of the pelvic sagittal retroversion. In degenerative lumbar scoliosis, patients with smaller PI tended to rely more on the pelvic retroversion to maintain the sagittal balance than patients with larger PI, or patients with smaller PI were likely to start up the pelvic retroversion compensatory mechanism earlier than the patients with larger PI.

Correlation between paravertebral spread of injectate and clinical efficacy in lumbar transforaminal block.

The potential paravertebral space includes spinal nerves, dorsal rami, rami communicants, and sympathetic chains. This study evaluated correlations between paravertebral spread of injectate and clinical efficacy in lumbar transforaminal block. We retrospectively analysed the data of 88 patients who received transforaminal blocks for lumbar radicular pain. We categorized patients into two groups: patients with ≥ 50% pain reduction on a numeric rating scale at 30 min following a block (responder group), and patients with < 50% pain reduction (non-responder group). Paravertebral spread of injectate was graded as limited to the anterior, middle, and posterior 1/3 of the anterolateral aspect of vertebral bodies; spread between the posterolateral margins of bodies and the posterior epidural space was considered no spread. Clinical and fluoroscopic data, perfusion index, temperature, and cold sensation were compared between the groups. Among 54 patients analysed, 26 (48.1%) experienced ≥ 50% and 28 (51.9%) < 50% pain reduction. Paravertebral spread occurred in 33 (61.1%) patients; 19 (57.6%) responders and 14 (42.4%) non-responders. On analysis, paravertebral spread, epidural spread patterns, perfusion index change ratios, temperature changes, and cold sensation changes showed no differences between responder and non-responder groups. Paravertebral spread occurred in 61.1%, with no correlation with the clinical efficacy of lumbar transforaminal block.

Comparison of 1-year results of single transforaminal epidural steroid injection among patients with different spinal pathologies-related radicular pain.

AIMS: This study aims to investigate the effectiveness of transforaminal epidural steroid injection (TFESI) in patients with lumbar radicular pain or radiculopathy caused by different spinal pathologies. METHODS: One hundred and seventy seven patients who underwent single transforaminal epidural steroid injection were included in the study group and divided into 3 subgroups (central spinal stenosis + lateral recess stenosis, foraminal stenosis, lumbar disc herniation) according to existing spinal pathology. Patients' visuel analogue scale (VAS) measures and Oswestry Disability Index (ODI) scores were recorded and the patients who give favourable response to treatment were called respondents and who were not called as non-respondents. Subgroups were compared statistically at the end of 12 months. RESULTS: Sixty patients (33.9%) were considered as respondents and 117 patients (66.1%) were non-respondents in the entire study group. Patients with foraminal stenosis included the vast majority of the respondents and showed better results of pain relief as opposed to patients of other groups at the end of 12 months (P < 0.001). CONCLUSION: TFESI was an effective treatment modality for pain relief and functional improvement in patients with foraminal stenosis. However, it could not produce the same results in patients with central spinal stenosis and lumbar disc herniations.

Lumbar Canal Stenosis: A Prospective Clinicoradiologic Analysis.

BACKGROUND: Although spinal canal narrowing is thought to be the defining feature for the clinical diagnosis of lumbar canal stenosis, the degree of spinal canal stenosis necessary to elicit neurologic symptoms is not clear. Several studies have been performed to detect an association between a narrow spinal canal and clinical symptoms. Through our prospective study, we compared the radiologic criteria with the clinical criteria using the Oswestry Disability Index (ODI) and assessed how they correlate. MATERIALS AND METHODS: We used the qualitative grading (morphological classification system on magnetic resonance imaging [MRI]) system, dural sac cross-sectional area (DSCA), and sedimentation sign on MRI images and compared them with the Self-Paced Walking Ability (Self-Paced Walking Test) and ODI of the patients in the study. The systems were applied to 85 patients divided into three groups: group A: 43 patients with neurogenic claudication and able to walk < 30 minutes; group B: 11 patients with neurogenic claudication and able to walk > 30 minutes; and group C: 31 patients with simple back pain and no signs of neurologic claudication. RESULTS: The mean ODI was 21.19 in group C, 46.50 in group B, and 61.95 in group A. The difference was statistically significant. The mean DSCA was 164.42 mm2 in group C, 49.94 mm2 in group B, and 35.07 mm2 in group A. The difference was statistically significant. The sedimentation sign was negative in 96.8% patients in group C, 54.5% patients in group B, and 32.6% patients in group A. The difference was statistically significant. Group C had 9.3% patients in morphology grade A3, 51.6% in grade A2, and 38.7% patients in grade A1. Group B had 63.6% patients in grade C, 18.2% patients in grade B, 9.1% in grade A4, and 9.1% in grade A3. Group A had 18.6% patients in grade D, 39.5% in grade C, 27.9% in grade B, 11.6% in grade A4, and 2.3% in grade A3. The mean DSCA of group C was significantly different from group A and group B, but the difference of the mean DSCA between group A and group B was not statistically significant. The relationship of ODI to DSCA, ODI to sedimentation sign, and ODI to morphological grading for group C and group A was not statistically significant. The relationship of morphological grading to DSCA was statistically significant for all three groups. CONCLUSION: DSCA, morphological grading, and sedimentation sign are good to excellent radiologic indicators differentiating patients with simple back pain from those with lumbar spinal stenosis. Clinically, ODI is an excellent indicator of the severity of stenosis. But ODI statistically has no significant correlation to any of these radiologic parameters.

Sagittally Balanced Degenerative Spondylolisthesis Patients With Increased Sacral Slope and Greater Lumbar Lordosis Experience Less Back Pain After Short-Segment Lumbar Fusion Surgery.

STUDY DESIGN: A retrospective review of prospectively collected registry data. OBJECTIVES: (1) Examine functional outcomes of patients with postoperative sacral slope (SS)<30 degrees versus SS≥30 degrees after single-level transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis (DS); (2) determine the factors associated with SS at the last follow-up. SUMMARY OF BACKGROUND DATA: Few studies have examined the relationship between spinopelvic parameters and functional outcomes in patients with DS undergoing short-segment TLIF. Although SS of 30 degrees has been proposed as the ideal spinopelvic parameter for eliminating residual pain and disability in adult spinal deformity, the ideal value for DS remains unknown. METHODS: Prospectively collected registry data of 63 patients who underwent single-level L4-L5 open TLIF with sagittal realignment for DS were reviewed. Pelvic incidence, lumbar lordosis (LL), pelvic tilt, SS, listhesis excursion, and Bridwell fusion grading were recorded. Patients were stratified into SS<30 degrees (n=26) or SS≥30 degrees (n=37) at the last follow-up. All patients were assessed preoperatively and postoperatively at 2 years. Receiver operating characteristics curve analysis was used to assess the relationship between expectation fulfillment and change in SS. RESULTS: Patients with SS≥30 degrees had significantly lower back pain at 2 years (P<0.04). There were no differences in leg pain or outcome scores (Oswestry Disability Index, Short-Form 36 Physical, and Mental Component Summaries), although there was a trend towards better outcomes and higher satisfaction/expectation fulfillment in patients with SS≥30 degrees. The SS≥30 degrees group had a higher preoperative LL (P=0.04) and SS (P<0.01). Preoperative SS was correlated with SS (R=0.71, P<0.01) and LL (R=0.51, P<0.01) at the last follow-up. The area under the curve for change in SS was 0.680 (95% confidence interval, 0.453-0.907) for predicting expectation fulfillment at 2 years. CONCLUSIONS: Patients with increased SS (≥30 degrees) experienced less back pain after short-segment lumbar fusion surgery. This was associated with increased LL postoperatively, indicating better sagittal balance.

Revision Surgery after Percutaneous Endoscopic Transforaminal Discectomy Compared with Primary Open Surgery for Symptomatic Lumbar Degenerative Disease.

OBJECTIVE: To evaluate the clinical outcome of reoperation after percutaneous endoscopic lumbar discectomy (PELD) as compared with primary spinal decompression and fusion. METHODS: A retrospective study from December 2014 to December 2017 was conducted at Peking Union Medical College Hospital and comprised 39 patients with symptomatic lumbar degenerative disease (LDD): 13 post-PELD who underwent reoperation (revision surgery group) and 26 who received primary spinal decompression and fusion (primary open surgery group). The two groups were compared regarding: operative time, blood loss, transfusion, hospitalization, postoperative visual analog scale (VAS) scores, Oswestry Disability Index (ODI) scores, Japanese Orthopedic Association (JOA) improvement rate, and postoperative complications. The Mann-Whitney U-test was applied to analyze continuous parameters, and the χ2 -test for categorical parameters. Fisher's exact test was used for small data subsets. RESULTS: There was no statistically significant difference between the two groups in mean age (52.7 years vs 52.9 years), gender ratio (6 men-to-7 women vs 12 men-to-14 women), body mass index, medical history, preoperative diagnosis, or surgical spine level (P > 0.05). The mean operative time of the revision surgery group was significantly longer than that of the primary open surgery group (160.0 min vs 130.2 min, P < 0.05). The revision surgery group also had a significantly higher mean estimated blood loss, postoperative drainage, and length of hospital stay (P < 0.05). However, no significant differences were found between the two groups in terms of hemoglobin and hematocrit values, preoperatively and postoperatively. The rate of transitional neurological irritation was higher in the revision surgery group (61.5% vs 3.8%; P < 0.05), as was intraoperative durotomy and cerebrospinal fluid leakage (30.8% vs 3.8%, P < 0.05). At 1 month, the VAS and ODI scores of the primary open surgery group were significantly better than those of the revision surgery group, while the improvement in JOA scores was similar. After 6 and 12 months' follow-up, the VAS and ODI scores and the rates of JOA improvement were comparable. CONCLUSION: Patients with LDD who received primary spinal decompression and fusion experienced lower rates of perioperative complications and shorter hospitalization compared with patients who underwent revision surgery after PELD, but the clinical outcomes at the last follow-up of both groups were satisfactory.

Relationship between Endplate Defects, Modic Change, Disc Degeneration, and Facet Joint Degeneration in Patients with Low Back Pain.

PURPOSE: The endplate defects (EDs), Modic changes (MCs), disc degeneration (DD), facet orientation (FO), and facet tropism (FT) were demonstrated to be related to the low back pain (LBP). The aim of this study was to investigate possible correlations between them. METHODS: 75 patients were reviewed to evaluate the degenerative change in vertebral bodies (EDs and MCs), intervertebral discs (DD), and facet joint degeneration (FO and FT). All patients were categorized into four groups based on the grade of EDs. Clinical outcomes were evaluated with the visual analog scale (VAS) and Oswestry disability index (ODI) before and after surgery. RESULTS: There was no difference between the four groups in baseline characteristics except for gender and weight. FT is positively correlated with FO. The same rule exists between EDs, the size of MCs II, FO (left) and FO (right), and VAS and ODI. The grade of EDs is positively correlated with the grade of DD. L4-L5 can bear more load than other levels; thus, the grade of EDs is higher than that of other lumbar levels. The preoperative LBP was relieved in all groups in varying degrees. The change of pain and dysfunction is inversely proportional to the grade of EDs in the general trend. CONCLUSION: The relationship between weight, gender, and disc degeneration provided a mechanism by which increasing weight can predispose to DD. Different grades of EDs had different effects on patients with LBP. There was a significant correlation between EDs, MCs II, DD, FT, and FO.

Utility of neuromonitoring during lumbar pedicle subtraction osteotomy for adult spinal deformity.

OBJECTIVE: The benefits and utility of routine neuromonitoring with motor and somatosensory evoked potentials during lumbar spine surgery remain unclear. This study assesses measures of performance and utility of transcranial motor evoked potentials (MEPs) during lumbar pedicle subtraction osteotomy (PSO). METHODS: This is a retrospective study of a single-surgeon cohort of consecutive adult spinal deformity (ASD) patients who underwent lumbar PSO from 2006 to 2016. A blinded neurophysiologist reviewed individual cases for MEP changes. Multivariate analysis was performed to determine whether changes correlated with neurological deficits. Measures of performance were calculated. RESULTS: A total of 242 lumbar PSO cases were included. MEP changes occurred in 38 (15.7%) cases; the changes were transient in 21 cases (55.3%) and permanent in 17 (44.7%). Of the patients with permanent changes, 9 (52.9%) had no recovery and 8 (47.1%) had partial recovery of MEP signals. Changes occurred at a mean time of 8.8 minutes following PSO closure (range: during closure to 55 minutes after closure). The mean percentage of MEP signal loss was 72.9%. The overall complication rate was 25.2%, and the incidence of new neurological deficits was 4.1%. On multivariate analysis, MEP signal loss of at least 50% was not associated with complication (p = 0.495) or able to predict postoperative neurological deficits (p = 0.429). Of the 38 cases in which MEP changes were observed, the observation represented a true-positive finding in only 3 cases. Postoperative neurological deficits without MEP changes occurred in 7 cases. Calculated measures of performance were as follows: sensitivity 30.0%, specificity 84.9%, positive predictive value 7.9%, and negative predictive value 96.6%. Regarding the specific characteristics of the MEP changes, only a signal loss of 80% or greater was significantly associated with a higher rate of neurological deficit (23.0% vs 0.0% for loss of less than 80%, p = 0.021); changes of less than 80% were not associated with postoperative deficits. CONCLUSIONS: Neuromonitoring has a low positive predictive value and low sensitivity for detecting new neurological deficits. Even when neuromonitoring is unchanged, patients can still have new neurological deficits. The utility of transcranial MEP monitoring for lumbar PSO remains unclear but there may be advantages to its use.

Modic Changes Are Not Associated With Long-term Pain and Disability: A Cohort Study With 13-year Follow-up.

STUDY DESIGN: A comparative cohort study with 13-year follow-up. OBJECTIVE: To assess whether Modic changes (MCs) are associated with long-term physical disability, back pain, and sick leave. SUMMARY OF BACKGROUND DATA: Previous studies have shown a conflicting association of low back pain (LBP) with MCs and disc degeneration. The long-term prognosis of patients with MCs is unclear. METHODS: In 2004 to 2005, patients aged 18 to 60 with daily LBP were enrolled in an randomized controlled trial study and lumbar magnetic resonance imaging (MRI) was performed. Patients completed numeric rating scales (0-10) for LBP and leg pain, Roland-Morris Disability Questionnaire (RMDQ), LBP Rating Scale for activity limitations (RS, 0-30), inflammatory pain pattern and sick leave days due to LBP at baseline and 13 years after the MRI. Patients were stratified based on the presence (+MC) or absence (-MC) of MCs on the MRI. RESULTS: Of 204 cases with baseline MRI, 170 (83%) were available for follow-up; 67 (39%) with MCs and 103 (61%) without MCs. Demographics, smoking status, BMI, use of antibiotics, LBP, leg pain, and inflammatory pain pattern scores at baseline and at 13-year follow-up were similar between the two groups. Also, baseline RMDQ was similar between the +MC and -MC groups. At 13 years, the RMDQ score was statistically significant better in the +MC group (7.4) compared with the -MC group (9.6, P = 0.024). Sick leave days due to LBP were similar at baseline but less in the +MC group (9.0) compared with the -MC group (22.9 d, P = 0.003) at 13 years. CONCLUSION: MCs were not found to be negatively associated with long-term pain, disability, or sick leave. Rather, the study found that LBP patients with MCs had significantly less disability and sick-leave at long-term follow-up. We encourage further studies to elucidate these findings. LEVEL OF EVIDENCE: 2.

An evaluation of contrast dispersal pattern on preganglionic epidural injection through trans-lateral recess approach in patients with lumbosacral radiculopathy.

PURPOSE: To evaluate the accessibility of the preganglionic epidural space in patients with lumbosacral radiculopathy treated with epidural steroid injection (ESI) through trans-lateral recess (TLR) approach. METHODS: From September 2016 to December 2016, we enrolled 50 consecutive preganglionic ESI through TLR approach for 38 patients with lumbosacral radiculopathy at or below L4 territory. Fifteen of patients were diagnosed with lumbar disc herniation and 23 with lumbar spinal stenosis. TLR epidural injection was performed with 20-G Tuohy needles. To achieve proper final needle placement (i.e., in the axillary portion between the exiting and transversing nerve roots), the needle direction was set laterally from the center of the infra-adjacent spinous process to the medial wall of the corresponding pedicle and superiorly from the distal tip of infra-adjacent spinous process to the corresponding vertebral foramen. Finally, 1 mL of contrast was injected to assess the epidurographic pattern. RESULTS: All patients achieved filling of the dorsal and ventral epidural space. Rostral spreading along the exiting nerve root to the foramen of target segment was present in 48/50 (96%) patients and caudal spreading along the transversing nerve root to the foramen of lower segment in 45/50 (90%) patients. No intravascular injection or dural puncture-related neural complications were observed. CONCLUSIONS: When delivered using the TLR approach, epidural injections result in excellent drug spread within the preganglionic area (i.e., ventral epidural contrast filling and periradicular infiltration of exiting and transversing nerve roots). As noted previously that higher rates of pre-ganglionic epidural infiltration might be led to improvements in clinical pain and disability, epidural injections delivered using the TLR approach are expected to complement existing epidural modalities. These slides can be retrieved under Electronic Supplementary Material.

Autologous mesenchymal stromal cells embedded in tricalcium phosphate for posterolateral spinal fusion: results of a prospective phase I/II clinical trial with long-term follow-up.

BACKGROUND: Posterolateral spinal fusion with autologous bone graft is considered the "gold standard" for lumbar degenerative disc disease (DDD) when surgical treatment is indicated. The potential role of mesenchymal stromal cells (MSCs) to replace the bone graft in this setting has not been fully addressed. OBJECTIVE: To analyze the safety, feasibility and potential clinical efficacy of the implantation of autologous MSCs embedded with tricalcium phosphate as a therapeutic alternative to bone graft in patients with DDD during posterolateral spine fusion. STUDY DESIGN: Phase I/II single-arm prospective clinical trial. METHODS: Eleven patients with monosegmental DDD at L4-L5 or L5-S1 level were included. Autologous bone marrow-derived MSC were expanded in our Good Manufacturing Practice (GMP) Facility and implanted during spinal surgery embedded in a tricalcium phosphate carrier. Monitoring of patients included a postoperative period of 12 months with four visits (after the 1st, 3rd, 6th, and 12th month), with clinical and radiological assessment that included the visual analog scale (VAS), the Oswestry disability index (ODI), the Short-Form Health Survey (SF-36), the vertebral fusion grade observed through a simple Rx, and the evaluation of possible complications or adverse reactions. In addition, all patients were further followed up to 5 years for outcome. RESULTS: Median age of patients included was 44 years (range 30-58 years), and male/female ratio was (6/5) L4-L5 and L5-S1 DDD was present five and six patients, respectively. Autologous MSCs were expanded in all cases. There were no adverse effects related to cell implantation. Regarding efficacy, both VAS and ODI scores improved after surgery. Radiologically, 80% of patients achieved lumbar fusion at the end of the follow-up. No adverse effects related to the procedure were recorded. CONCLUSIONS: The use of autologous MSCs for spine fusion in patients with monosegmental degenerative disc disease is feasible, safe, and potentially effective. TRIAL REGISTRATION: no. EudraCT: 2010-018335-17 ; code Identifier: NCT01513694 ( clinicaltrials.gov ).

[Advances in the study of anatomy and biomechanics of lumbosacral transitional vertebrae].

Lumbosacral transitional vertebrae (LSTV) is a common phenomena of developmental anomaly, which is characterized by anatomic variation and biomechanical changes. LSTV is often accompanied with low back pain, lumbar disc herniation, lumbar spinal stenosis, lumbar spondylolisthesis and other spinal diseases. The diagnosis of LSTV has a great significance for proper treatment process. Early imageological studies have limitations on distinguishing different types of LSTV from the aspect of morphological changes. This review focuses on recent studies of LSTV anatomy and variation, its influence in local biomechanics and spinal alignment, and its relationship with spinal diseases.

Expectations for Postoperative Improvement in Health-Related Quality of Life in Young Patients With Lumbosacral Spondylolisthesis: A Prospective Cohort Study.

STUDY DESIGN: Prospective multicenter study of the changes in Scoliosis Research Society Outcome Questionaire 22 (SRS-22) scores for 78 patients younger than 25 years old surgically treated for lumbosacral spondylolisthesis OBJECTIVE.: Report the change of health-related quality of life (HRQOL) in patients younger than 25 years after surgical treatment of lumbosacral spondylolisthesis. SUMMARY OF BACKGROUND DATA: There is a paucity of data with regard to the influence of surgical treatment on the HRQOL of patients with lumbosacral spondylolisthesis. Large prospective studies are needed to clearly define the benefits of surgery in the young patient population. METHODS: A prospective multicenter cohort of 78 patients younger than 25 years (14.8 ±â€Š2.9, range: 7.9-23.6 yr) undergoing posterior fusion for lumbosacral spondylolisthesis were enrolled. There were 17 patients with low-grade (<50%) and 61 with high-grade (≥50%) slips. SRS-22 scores calculated before surgery and after 2 years of follow-up were compared for all patients using two-tailed paired t tests. Subanalyses for low- and high-grade patients were done using two-tailed Wilcoxon signed ranked and paired t tests, respectively. The level of significance was set at 0.05. RESULTS: HRQOL was significantly improved 2 years after surgery for all domains and for the total score of the SRS-22 questionnaire. The individual total score was improved in 66 patients (85%), and 52 patients (67%) improved by at least 0.5 point. All domains and the total score of the SRS-22 questionnaire were significantly improved for high-grade patients, whereas only pain, function, and total score were improved for low-grade patients. CONCLUSION: This is the largest study comparing the HRQOL before and after surgery in young patients with low- and high-grade lumbosacral spondylolisthesis. HRQOL significantly improves after surgery for the majority of patients, especially for high-grade patients. This study helps clinicians to better counsel patients with regard to the benefits of surgery for lumbosacral spondylolisthesis. LEVEL OF EVIDENCE: 2.

S1 Pedicle Subtraction Osteotomy for Fixed Sagittal Imbalance and Lumbosacral Kyphosis.

S1 pedicle subtraction osteotomies (PSOs) are indicated in patients with fixed, high-grade L5-S1 spondylolisthesis or kyphosis secondary to a sacral fracture, who present with severe sagittal imbalance. Unlike lumbar PSOs, sacral osteotomies are rare, and there is a paucity of literature outlining techniques. Here, we present the indications, planning, technique, and outcomes for S1 PSOs.

Education level as a prognostic indicator at 12 months following decompression surgery for symptomatic lumbar spinal stenosis.

OBJECTIVEThe goal of this study was to analyze the effect of patient education level on functional outcomes following decompression surgery for symptomatic lumbar spinal stenosis.METHODSPatients with surgically decompressed symptomatic lumbar stenosis were collected in a prospective observational registry at a single institution between 2012 and 2014. Patient education level was compared to surgical outcomes to elucidate any relationships. Outcomes were defined using the Oswestry Disability Index score, back and leg pain visual analog scale (VAS) score, and the EuroQol-5 Dimensions questionnaire score.RESULTSOf 101 patients with symptomatic lumbar spinal stenosis, 27 had no college education and 74 had a college education (i.e., 2-year, 4-year, or postgraduate degree). Preoperatively, patients with no college education had statistically significantly greater back and leg pain VAS scores when compared to patients with a college education. However, there was no statistically significant difference in quality of life or disability between those with no college education and those with a college education. Postoperatively, patients in both cohorts improved in all 4 patient-reported outcomes at 3 and 12 months after treatment for symptomatic lumbar spinal stenosis.CONCLUSIONSDespite their education level, both cohorts showed improvement in their functional outcomes at 3 and 12 months after decompression surgery for symptomatic lumbar spinal stenosis.

The five-repetition sit-to-stand test: evaluation of a simple and objective tool for the assessment of degenerative pathologies of the lumbar spine.

OBJECTIVE: Recently, objective functional tests have generated interest since they can supplement an objective dimension to clinical assessment. The five-repetition sit-to-stand (5R-STS) test is a quick and objective tool that tests movements frequently used in everyday life. The aim of this prospective study was to evaluate the validity and reliability of the 5R-STS test in patients with degenerative pathologies of the lumbar spine. METHODS: Patients and healthy volunteers completed the standardized 5R-STS, Roland-Morris Disability Questionnaire (RMDQ), Oswestry Disability Index (ODI), visual analog scale (VAS) for back and leg pain, and EQ-5D for health-related quality of life (HRQOL). To assess convergent validity, the 5R-STS test times were correlated with these questionnaires. RESULTS: Overall, 157 patients and 80 volunteers were enrolled. Direct correlation with RMDQ (r = 0.49), ODI (r = 0.44), and VAS for back pain (r = 0.31) and indirect correlation with the EQ-5D index (r = -0.41) were observed (p < 0.001). The 5R-STS test showed no correlation with VAS for leg pain and EQ-5D VAS (p > 0.05). In 119 individuals, the 5R-STS test demonstrated excellent test-retest reliability with an intraclass correlation coefficient of 0.98. The upper limit of normal, distinguishing patients with and without objective functional impairment, was identified as 10.35 seconds. A severity stratification classified patients with test times of 10.5-15.2, 15.3-22.0, or greater than 22.0 seconds as having mild, moderate, or severe functional impairment, respectively. CONCLUSIONS: The 5R-STS test is a simple and effective tool to describe objective functional impairment. A patient able to perform the test in 10.4 seconds can be considered to have no relevant objective functional impairment. Clinical trial registration no.: NCT03303300 (clinicaltrials.gov).