Response to Preoperative Steroid Injections Predicts Surgical Outcomes in Patients Undergoing Fusion for Isthmic Spondylolisthesis.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The decision to pursue operative intervention for patients with isthmic spondylolisthesis is complex. Although steroid injections are a well-accepted therapeutic modality that may delay or obviate surgery, little is known regarding their ability to predict surgical outcomes. SUMMARY OF BACKGROUND DATA: Here, we examine whether improvement after preoperative steroid injections can accurately predict clinical outcomes after surgery. METHODS: A retrospective cohort analysis was performed on adult patients undergoing primary posterolateral lumbar fusion for isthmic spondylolisthesis between 2013 and 2021. Data were stratified into a control (no preoperative injection) group and an injection group (received a preoperative diagnostic and therapeutic injection). We collected demographic data, peri-injection visual analog pain scores (VAS) pain scores, PROMIS pain interference and physical function scores, Oswestry Disability Index, and VAS pain (back and leg). Student t test was utilized to compare baseline group characteristics. Linear regression was performed comparing changes in peri-injection VAS pain scores and postoperative measures. RESULTS: Seventy-three patients did not receive a preoperative injection and were included in the control group. Fifty-nine patients were included in the injection group. Of patients who received an injection, 73% had >50% relief of their preinjection VAS pain score. Linear regression revealed a positive interaction between the injection efficacy and postoperative pain relief as measured by VAS leg scores ( P <0.05). There was also an association between injection efficacy and back pain relief, though this did not achieve statistical significance ( P =0.068). No association was found between injection efficacy and improvement in Oswestry Disability Index or PROMIS measures. CONCLUSIONS: Steroid injections are often utilized in the nonoperative therapeutic management of patients with lumbar spine disease. Here, we demonstrate the diagnostic value of steroid injections in predicting postoperative leg pain relief in patients undergoing posterolateral fusion for isthmic spondylolisthesis.

Usefulness of discography, discoblock and a new mechanical method for identifying a painful segment/disc.

BACKGROUND: We previously described a procedure for eliciting deep spatial discrimination of individual segments in the healthy lumbar spine of normal subjects: the percutaneous mechanical provocation (PMP) test. Our goal was to devise a method for accurate identification of the spinal level of pathology in chronic low back pain (CLBP). In the present study, we validated the PMP test, using a subgroup of CLBP patients with isthmic spondylolisthesis (IS). Because there is clinical consensus that IS back pain originates in the slipped segment/disc, the level of pathology can be directly compared to the result of the PMP test. The test is agnostic with respect to the underlying pathological mechanism, and therefore might be useful in identifying the involved segment(s) irrespective of the painful structure. METHODS: In 37 patients with confirmed IS (slippage 3-15mm), we compared sensitivity between the PMP test, the widely used provocative discography test and the discoblock test. RESULTS: The PMP test reliably identified the slip level in patients with IS, with sensitivity of 92%. Accepting the slipped disc as the origin of pain in IS, the sensitivity of the provocative discography and discoblock tests were 49% and 35%, respectively: i.e., too low to be contributive in clinical practice. CONCLUSIONS: The PMP test reliably identified the origin of localized pain in IS as the slip level, but should be used with care in CLBP patients in selecting discogenic pain patients for fusion surgery, since the specificity of the test is not known and it may be positive for any origin of localized pain.

Evaluation and Management of Cauda Equina Syndrome.

Cauda equina syndrome is a potentially devastating spinal condition. The diagnosis of cauda equina syndrome lacks sensitivity and specificity, sometimes occurring after irreparable neurological damage has happened. Timely diagnosis and treatment is imperative for optimal outcomes and for avoiding medicolegal ramifications. Cauda equina syndrome results from conditions that compress the nerves in the lumbosacral spinal canal. Although no consensus definition exists, it generally presents with varying degrees of sensory loss, motor weakness, and bowel and bladder dysfunction (the latter of which is required to definitively establish the diagnosis). A thorough history and physical exam is imperative, followed by magnetic resonance or computed tomography imaging myelogram to aid in diagnosis and treatment. Once suspected, emergent spinal surgery referral is indicated, along with urgent decompression. Even with expeditious surgery, improvements remain inconsistent. However, early intervention has been shown to portend greater chance of neurologic recovery. All providers in clinical practice must understand the severity of this condition. Providers can optimize long-term patient outcomes and minimize the risk of litigation by open communication, good clinical practice, thorough documentation, and expeditious care.

Decompression alone versus decompression and instrumented fusion for the treatment of isthmic spondylolisthesis: a randomized controlled trial.

OBJECTIVE: The most advocated surgical technique to treat symptoms of isthmic spondylolisthesis is decompression with instrumented fusion. A less-invasive classical approach has also been reported, which consists of decompression only. In this study the authors compared the clinical outcomes of decompression only with those of decompression with instrumented fusion in patients with isthmic spondylolisthesis. METHODS: Eighty-four patients with lumbar radiculopathy or neurogenic claudication secondary to low-grade isthmic spondylolisthesis were randomly assigned to decompression only (n = 43) or decompression with instrumented fusion (n = 41). Primary outcome parameters were scores on the Roland Disability Questionnaire (RDQ), separate visual analog scales (VASs) for back pain and leg pain, and patient report of perceived recovery at 12-week and 2-year follow-ups. The proportion of reoperations was scored as a secondary outcome measure. Repeated measures ANOVA according to the intention-to-treat principle was performed. RESULTS: Decompression alone did not show superiority in terms of disability scores at 12-week follow-up (p = 0.32, 95% CI -4.02 to 1.34), nor in any other outcome measure. At 2-year follow-up, RDQ disability scores improved more in the fusion group (10.3, 95% CI 3.9-8.2, vs 6.0, 95% CI 8.2-12.4; p = 0.006, 95% CI -7.3 to -1.3). Likewise, back pain decreased more in the fusion group (difference: -18.3 mm, CI -32.1 to -4.4, p = 0.01) on a 100-mm VAS scale, and a higher proportion of patients perceived recovery as showing "good results" (44% vs 74%, p = 0.01). Cumulative probabilities for reoperation were 47% in the decompression and 13% in the fusion group (p < 0.001) at the 2-year follow-up. CONCLUSIONS: In patients with isthmic spondylolisthesis, decompression with instrumented fusion resulted in comparable short-term results, significantly better long-term outcomes, and fewer reoperations than decompression alone. Decompression with instrumented fusion is a superior surgical technique that should in general be offered as a first treatment option for isthmic spondylolisthesis, but not for degenerative spondylolisthesis, which has a different etiology.

One-year clinical outcome after full-endoscopic interlaminar lumbar discectomy for isthmic lumbar spondylolisthesis: Two case reports.

RATIONALE: For isthmic lumbar spondylolisthesis (ILS) associated with the removal of herniation, it remains challenging to perform less invasive and minimally disruptive procedures. Good results could potentially be obtained by further preserving the posterior elements in full-endoscopic lumbar discectomy (FESS), which is less invasive than microenscopic surgery (MES). PATIENT CONCERNS: One patient complained of left leg pain, and another patient complained of right leg pain and low back pain. DIAGNOSES: Two patients with ILS and Meyerding Grade 1 lumbar spondylolisthesis. INTERVENTIONS: We performed a full-endoscopic lumbar discectomy via the interlaminar space (FESS-IL) for L5/S1 lumbar disc herniation (LDH) accompanied by isthmic lumbar spondylolisthesis. FESS-IL was performed in 2 patients with radiculopathy caused by different types of LDH using a full endoscopic system with a 4.1 mm working channel and 6.9 mm outer diameter. A 3.5-mm diameter high-speed drill was used in one patient for an upward-migrated LDH in the inner-rim of the infravertebral border. The other patient underwent minimal resection without bone resection. OUTCOMES: The one-year clinical outcome included confirmation of pain relief and evacuation of migrated LDH on magnetic resonance imaging in all patients. There was no progression of slippage on radiography. The mean operative time was 82 min, and no complication was observed. The one-year clinical outcome demonstrated sufficient pain relief. LESSONS THE Y: ear postoperative outcome showed improvement. We believe that FESS-IL is a viable alternative operative approach for LDH for ILS.

Comparison of outcomes between indirect decompression of oblique lumbar interbody fusion and MIS-TLIF in one single-level lumbar spondylosis.

Minimal invasive spinal fusion has become popular in the last decade. Oblique lumbar interbody fusion (OLIF) is a relatively new surgical technique and could avoid back muscle stripping and posterior complex destruction as in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Between December 2016 and September 2018, patients with single level degenerative spondylosis were selected to enroll in this retrospective study. A total of 21 patients that underwent OLIF and 41 patients that received MIS-TLIF were enrolled. OLIF showed significantly less blood loss and shorter surgery time compared to MIS-TLIF (p < 0.05). The improvement in segmental lordosis and coronal balance was significantly more in OLIF group than MIS-TLIF group (p < 0.05). When comparing with MIS-TLIF, OLIF was significantly better in Oswestry Disability Index (ODI) and visual analogue scale for back pain improvement at post-operative 6 months (p < 0.05). Both OLIF and MIS-TLIF are becoming mainstream procedures for lumbar degenerative-related disease, especially for spondylolisthesis. However, the indirect decompression of OLIF has shown to have less perioperative blood loss and shorter surgery time than that of MIS-TLIF. In addition, OLIF gives superior outcome in restoring segmental lordosis and coronal imbalance. While both OLIF and MIS-TLIF provide optimal clinical outcomes, upon comparison between the two techniques, the indirect decompression of OLIF seems to be a superior option in modern days.

In-hospital Course and Complications of Laminectomy Alone Versus Laminectomy Plus Instrumented Posterolateral Fusion for Lumbar Degenerative Spondylolisthesis: A Retrospective Analysis of 1804 Patients from the NSQIP Database.

STUDY DESIGN: Retrospective analysis of data from the National Surgical Quality Improvement Program (NSQIP). OBJECTIVE: We sought to compare the short-term outcomes of laminectomy with/without fusion for single-level lumbar degenerative spondylolisthesis (DS). SUMMARY OF BACKGROUND DATA: Lumbar DS is a common cause of low back and radicular pain. Controversy remains over the safety and efficacy of fusion in addition to standard decompressive surgery. METHODS: Patients with lumbar DS who underwent laminectomy alone or laminectomy plus posterolateral fusion at a single level were identified from the 2012-2017 NSQIP database. Outcomes included 30-day mortality, major complication, reoperation, readmission, as well as operative duration, need for blood transfusion, length of stay (LOS), and discharge destination. Outcomes were compared between treatment groups by multivariable regression, adjusting for age, sex, and comorbidities (modified Frailty Index). Effect sizes were reported by adjusted odds ratio (aOR) or mean difference (aMD). RESULTS: The study cohort consisted of 1804 patients; of these, 802 underwent laminectomy alone and 1002 laminectomy plus fusion. On both unadjusted and adjusted analyses, there was no difference in 30-day mortality, major complications, reoperation, or readmission. However, laminectomy plus fusion was associated with longer operative time (170.0 vs. 152.7 minutes; aMD 16.00 minutes, P < 0.001), longer hospital LOS (3.2 vs. 2.5 days; aMD 0.68, P < 0.001), more frequent need for intra- or postoperative blood transfusion (6.8% vs. 3.1%; aOR 2.24, P = 0.001), and less frequent discharge home (80.7% vs. 89.2%; aOR 0.46, P < 0.001). CONCLUSION: We found single-level laminectomy plus fusion for lumbar DS to have a comparable short-term safety profile to laminectomy alone. However, fusion was associated with longer operative time and LOS, higher risk of blood transfusion, and greater need for inpatient rehabilitation. These factors should be recognized by clinicians and discussed with patients in the context of their values when weighing surgical treatment of lumbar DS.Level of Evidence: 3.

Comparative Effectiveness of Microdecompression Alone vs Decompression Plus Instrumented Fusion in Lumbar Degenerative Spondylolisthesis.

Importance: Conflicting evidence and large practice variation are present in the surgical treatment of degenerative spondylolisthesis. More than 90% of surgical procedures in the United States include instrumented fusion compared with 50% or less in other countries. Objective: To evaluate whether the effectiveness of microdecompression alone is noninferior to decompression with instrumented fusion in a real-world setting. Design, Setting, and Participants: This multicenter comparative effectiveness study with a noninferiority design assessed prospective data from the Norwegian Registry for Spine Surgery. From September 19, 2007, to December 21, 2015, 1376 patients at 35 Norwegian orthopedic and neurosurgical departments underwent surgery for lumbar spinal stenosis with degenerative spondylolisthesis without scoliosis. After excluding patients undergoing laminectomy alone, fusion without instrumentation, or surgery in more than 2 levels and those with a former operation at the index level, 794 patients were included in the analyses, regardless of missing or incomplete follow-up data, before propensity score matching. Data were analyzed from March 20 to October 30, 2018. Exposures: Microdecompression alone or decompression with instrumented fusion. Main Outcomes and Measures: A reduction from baseline of 30% or greater in the Oswestry Disability Index at 12-month follow-up. Results: After propensity score matching, 570 patients (413 female [72%]; mean [SD] age, 64.7 [9.5] years) were included for comparison, with 285 undergoing microdecompression (mean [SD] age, 64.6 [9.8] years; 205 female [72%]) and 285 undergoing decompression with instrumented fusion (mean [SD] age, 64.8 [9.2] years; 208 female [73%]). The proportion of each type of procedure varied between departments. However, changes in outcome scores varied within patients but not between departments. The proportion of patients with improvement in the Oswestry Disability Index of at least 30% was 150 of 219 (68%) in the microdecompression group and 155 of 215 (72%) in the instrumentation group. The 95% CI (-12% to 5%) for the difference of -4% was above the predefined margin of noninferiority (-15%). Microdecompression alone was associated with shorter operation time (mean [SD], 89 [44] vs 180 [65] minutes; P < .001) and shorter hospital stay (mean [SD], 2.5 [2.4] vs 6.4 [3.0] days; P < .001). Conclusions and Relevance: Among patients with degenerative spondylolisthesis, the clinical effectiveness of microdecompression alone was noninferior to that of decompression with instrumented fusion. Microdecompression alone was also associated with shorter durations of surgery and hospital stay, supporting the suggestion that the less invasive procedure should be considered for most patients.

Global sagittal spinal alignment in patients with degenerative low-grade lumbar spondylolisthesis.

PURPOSE: Global sagittal spinal alignment undergoes changes on the basis of sagittal malalignment (trunk inclined forward) in natural degenerative progression. We hypothesized that this change would associate with the disease state of the degenerative lumbar spondylolisthesis (DS). This study aimed to evaluate the global sagittal spinal alignment of low-grade DS by classifying in accordance with sagittal vertical axis (SVA). METHODS: The DS group was classified into three types according to the adult spinal deformity classification: type 1, SVA < 40 mm; type 2, 40 mm ≤ SVA < 95 mm; and type 3, 95 mm ≤ SVA. Age and sagittal spinal parameters (thoracic kyphosis, lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI)) were compared among three types. RESULTS: There were statistically significant differences in age, LL, PI, and PT among the three types. In comparison between two types, there was a statistically significant difference between type 1 and type 2 and between type 1 and type 3, but not between type 2 and type 3 in these parameters. PI tended to increase as the type increases. Furthermore, there was significant difference between types 1 and 3. CONCLUSION: We evaluated the features of the DS types classified by sagittal alignment. Large PI is one of the risk factors for SVA deterioration of DS. PI may be involved in the onset and progression of DS.

Evaluating low back pain in adolescents.

Low back pain in adolescents is a common complaint in primary care. With an average prevalence rate of 40%, adolescent low back pain correlates with greater healthcare use, higher incidences of adult back pain, and negative effects on overall well-being. A thorough history and physical examination can increase early detection and accurate diagnosis while ensuring the judicious use of diagnostic modalities. Although underlying serious pathology is rare in adolescents with low back pain, clinicians should recognize specific signs and symptoms that necessitate urgent evaluation and intervention. This article emphasizes the value of using a thorough history and physical examination to guide the initial diagnostic workup and to enhance the early detection and accurate diagnosis of adolescents who present with low back pain.

Comparison of the French and CARDS classifications for lumbar degenerative spondylolisthesis: reliability and validity.

BACKGROUND: The aim of this study was to compare the reliability and validity of the CARDS and French classification systems for lumbar DS. METHODS: Between May 2013 and December 2016, 158 consecutive patients diagnosed with single-level lumbar DS were included in this study, and all underwent lumbar fusion. All patients underwent long-cassette standing anterioposterior and lateral radiographs of the spine preoperatively and postoperatively. The images were graded according to the CARDS and French classification systems by two orthopedic spinal surgeons and two orthopedic spinal fellows, independently. Clinical outcome measures used were the visual analog scale, Oswestry Disability Index, and the 36-Item Short Form Health Survey. Clinical data were collected before surgery and 1 year after surgery. RESULTS: A total of 146 patients were finally included in this study and followed up for at least 1 year. When grading using the CARDS system, the κ values for inter- and intraobserver reliability were 0.837 and 0.869, respectively, representing perfect agreement. The interobserver κ value for the French classification was 0.693 and the intraobserver κ value was 0.743, both representing substantial agreement. CARDS Type D patients have higher preoperative back pain scores and better improvement after surgery compared with non-Type D patients. Mean back and leg pain was worse in French Type 5 patients, while the most significant improvement was also seen in Type 5 patients after surgery. CONCLUSIONS: Both CARDS and French classification systems have acceptable reliability and validity. The CARDS system is easier to utilize and has better reliability. LEVEL OF EVIDENCE: IV.

Sex Differences in Opioid Use in Patients With Symptomatic Lumbar Stenosis or Spondylolisthesis Undergoing Lumbar Decompression and Fusion.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To investigate sex differences in opioid use after lumbar decompression and fusion surgery for patients with symptomatic lumbar stenosis or spondylolisthesis. SUMMARY OF BACKGROUND DATA: Recent studies have demonstrated higher prevalence of chronic pain states and greater pain sensitivity among women compared with men. Furthermore, differences in responsivity to pharmacological and non-pharmacological treatments have been observed. Whether sex differences in perioperative opioid use exists in patients undergoing lumbar fusion for symptomatic stenosis or spondylolisthesis remains unknown. METHODS: An insurance database, including private/commercially insured and Medicare Advantage beneficiaries, was queried for patients with symptomatic lumbar stenosis or spondylolisthesis undergoing index 1,2, or 3-level index lumbar decompression and fusion procedures between 2007 and 2016. Records were searchable by International Classification of diseases diagnosis and procedure codes, and generic drug codes specific to Humana. Opioid use 6-months prior to through 2-years after index surgery was assessed. The primary outcome was sex differences in opioid use after index lumbar surgery. The secondary outcome was independent predictors of prolonged opioid use after lumbar fusion. RESULTS: Of the 13,257 participants (females: 7871, 59.8%), 58.4% of women used opioids compared with 56.9% of men prior to index surgery. At 1-year after surgery, continuous opioid use was observed in 67.1% of women compared with 64.2% of men (P < 0.001). Within 2-years postoperatively, opioid use was observed in 83.1% of women versus 82.5% men. In a multivariate logistic regression analysis, female sex (odds ration [OR] 1.14, 95% confidence interval [CI]: 1.058-1.237), obesity (OR 1.10, 95% CI: 1.004-1.212), and preoperative narcotic use (OR 3.43, 95% CI: 3.179-3.708) was independently associated with prolonged (>1 yr) opioid use after index surgery. CONCLUSION: We observed a higher prevalence of chronic opioid use among women following lumbar fusion surgery. Female sex was independently associated with prolonged opioid use after index surgery. LEVEL OF EVIDENCE: 3.

The clinical efficacy of Shi-style lumbar manipulations for symptomatic degenerative lumbar spondylolisthesis: protocol for a randomized, blinded, controlled trial.

BACKGROUND: Symptomatic degenerative lumbar spondylolisthesis (DLS) presents spinal problems in daily life. Shi-style lumbar manipulation (SLM), as an alternative treatment for DLS, is popular in China. SLM is based on the channels and collaterals theory of the traditional Chinese medicine, in which the symptoms are believed to result from channel blockage and joint displacement. However, there is no solid evidence to show the effect of the SLM on the management of symptomatic DLS. METHODS/DESIGN: We conduct a prospective randomized, blinded, controlled trial to compare the effectiveness of SLM with mechanical lumbar traction and explore whether it could be a potential therapy for symptomatic DLS. A total of 60 patients with symptomatic DLS will be enrolled and treated with the SLM or mechanical lumbar traction for 2 weeks. VAS score and SF-36 questionnaire were assessed at baseline and at 2, 4, 12, and 24 weeks. Any signs of acute adverse reactions, such as lower limb paralysis or syndrome of cauda equina, will be recorded at each visit during treatment. DISCUSSION: Although the SLM has been used in China for many years to treat symptomatic DLS, there is a lack of consensus about its effectiveness. This trial will provide convincing evidence about the effect of SLM on symptomatic DLS. TRIAL REGISTRATION: Registered on 6 January 2019; the trial number is ChiCTR1900020519 .

Predictive model for long-term patient satisfaction after surgery for grade I degenerative lumbar spondylolisthesis: insights from the Quality Outcomes Database.

OBJECTIVESince the enactment of the Affordable Care Act in 2010, providers and hospitals have increasingly prioritized patient-centered outcomes such as patient satisfaction in an effort to adapt the "value"-based healthcare model. In the current study, the authors queried a prospectively maintained multiinstitutional spine registry to construct a predictive model for long-term patient satisfaction among patients undergoing surgery for Meyerding grade I lumbar spondylolisthesis.METHODSThe authors queried the Quality Outcomes Database for patients undergoing surgery for grade I lumbar spondylolisthesis between July 1, 2014, and June 30, 2016. The primary outcome of interest for the current study was patient satisfaction as measured by the North American Spine Surgery patient satisfaction index, which is measured on a scale of 1-4, with 1 indicating most satisfied and 4 indicating least satisfied. In order to identify predictors of higher satisfaction, the authors fitted a multivariable proportional odds logistic regression model for ≥ 2 years of patient satisfaction after adjusting for an array of clinical and patient-specific factors. The absolute importance of each covariate in the model was computed using an importance metric defined as Wald chi-square penalized by the predictor degrees of freedom.RESULTSA total of 502 patients, out of a cohort of 608 patients (82.5%) with grade I lumbar spondylolisthesis, undergoing either 1- or 2-level decompression (22.5%, n = 113) or 1-level decompression and fusion (77.5%, n = 389), met the inclusion criteria; of these, 82.1% (n = 412) were satisfied after 2 years. On univariate analysis, satisfied patients were more likely to be employed and working (41.7%, n = 172, vs 24.4%, n = 22; overall p = 0.001), more likely to present with predominant leg pain (23.1%, n = 95, vs 11.1%, n = 10; overall p = 0.02) but more likely to present with lower Numeric Rating Scale score for leg pain (median and IQR score: 7 [5-9] vs 8 [6-9]; p = 0.05). Multivariable proportional odds logistic regression revealed that older age (OR 1.57, 95% CI 1.09-2.76; p = 0.009), preoperative active employment (OR 2.06, 95% CI 1.27-3.67; p = 0.015), and fusion surgery (OR 2.3, 95% CI 1.30-4.06; p = 0.002) were the most important predictors of achieving satisfaction with surgical outcome.CONCLUSIONSCurrent findings from a large multiinstitutional study indicate that most patients undergoing surgery for grade I lumbar spondylolisthesis achieved long-term satisfaction. Moreover, the authors found that older age, preoperative active employment, and fusion surgery are associated with higher odds of achieving satisfaction.

Degenerative Lumbar Spondylolisthesis: Definition, Natural History, Conservative Management, and Surgical Treatment.

Degenerative lumbar spondylolisthesis is one of the most common causes of low back pain and is defined as displacement of one vertebra over subjacent vertebra, associated with degenerative changes, without an associated disruption or defect in the vertebral ring. Undersetanding natural history of degenerative spondylolisthesis is important to tailor an individualized management plan for each patient. A trial of conservative therapy may be considered for patients with low-grade spondylolisthesis presenting with radiculopathy and/or pseudoclaudication. These options may include physical therapy, epidural steroid injection, and pain medications. If unresolved, surgical options may include decompression alone or decompression and fusion.

Mismatch between rod bending and actual post-operative lordosis in lumbar arthrodesis with poly axial screws.

BACKGROUND: The question of rod bending is essential during posterior lumbar fusion. The role of posterior instrumentation during spinal surgery remains to be defined. Despite an appropriate bending, a mismatch between rod lordosis and lumbar lordosis can occur. There is no study on the link between rod bending and lordosis. The purpose of this study was to evaluate parameters that explain the mismatch between lumbar lordosis and rod bending in lumbar surgery using polyaxial screws. HYPOTHESIS: Radiological parameters explain the mismatch between the rod and the lordosis. METHODS: This study was monocentric, retrospective, descriptive and analytic. All patients with posterior L3L5 fusion in an university-affiliated hospital in 2017 were included. Patients with past surgical history of anterior fusion on the levels L3L5, Coronal malalignment with a Cobb angle superior to 5°, the use of dynamic fixation systems were excluded. We measured on immediate post-operative standing profile x-ray: pelvic incidency, lumbar lordosis, lordosis of the instrumented segment, the distance between posterior wall and rod (EcarT) which reflect how homogeneously the screws are put in depth, the angle between screw and rod (thetaMA), the angle between screw and superior endplate (lambdaMA), the rod lordosis. Univariate and multivariate analysis were conducted to see if there was a link between all those parameters and the mismatch: vertebral lordosis-rod lordosis. RESULTS: A total of 74 patients were included, mean age was 67. Eighteen were 360° fusion and 56 were postero-lateral fusions. There was no statistical association between demographic data, pelvic parameters, use of interbody devices and the mismatch. There was a statistical association between thetaMA, lambdaMA, EcarT and the mismatch (P<0,0001). A multivariate linear regression model was developed to create a new index: Mismatch analysis index. CONCLUSION: Our study is the first on the link between rod bending and lumbar lordosis. Three radiologic factors are involved in not obtaining the planned lordosis in short lumbar fusion with polyaxial screws. Two factors depend on the way the surgeon positions screw parallel to the superior vertebral endplate(lambdaMA), and with a homogeneous depth (EcarT). And the last factor: ThetaMA is depending on the surgical technique (compression on screws, osteotomies, monoaxial screws, use of interbody devices). LEVEL OF EVIDENCE: IV.

Acute rib fracture caused by preoperative positioning for direct lateral interbody fusion: A case report.

RATIONALE: Degenerative spondylolisthesis is defined as forward slippage of a vertebra with respect to the underlying vertebra and is associated with the induction of lumbar canal stenosis. The use of anterior column support for degenerative lumbar conditions has been well documented. Direct lateral interbody fusion (DLIF) gains access via a lateral approach through the retroperitoneal fat and psoas muscle. It avoids many of the access-related complications yet comes with its own risks and limitations. The location of the iliac wing precludes exposure of the L5-S1 disc space and may make L4-5 surgery difficult. Therefore, accurate preoperative patient positioning is essential. PATIENT CONCERNS: A 71-year-old female with a body mass index (BMI) of 39.2 kg/m (height 155.9 cm, weight 79.5 kg) presented with lumbar pain radiating to the left lower limb. She complained of neurologic claudication with more than 100 m ambulation. DIAGNOSIS: Plain standing view on spine radiography revealed L4-5 spondylolisthesis and disc-space narrowing. Magnetic resonance imaging (MRI) revealed severe L4-5 bilateral foraminal stenosis. After the first surgery, simple rib cage radiography was performed to examine the source of her right-sided flank pain and it revealed acute fracture of the right ninth and tenth ribs. INTERVENTIONS: The patient was laterally positioned on the table in an extreme bending position. The intervertebral cage was inserted in the L4-5 disc space and disc height was restored. With respect to the rib fracture, treatment was conservative. OUTCOMES: The patient's radiating pain was immediately relieved and her lower back pain disappeared at 3 months after surgery. The patient reported right-sided flank pain after the first surgery. Simple rib cage radiography was performed and revealed fracture of the right ninth and tenth ribs. Follow-up assessments conducted 2 months later revealed complete bony union. LESSONS: DLIF avoids many access-related complications. However, it is associated with other intraoperative complications, including injury to the lumbar nerve root and plexus. In addition, there are preoperative complications associated with improper patient placement on the table. In this case, the patient's obesity and strict positional requirements resulted in rib fracture. We suggest that surgeons consider this complication and exercise care in preoperative positioning.

Follow-up score, change score or percentage change score for determining clinical important outcome following surgery? An observational study from the Norwegian registry for Spine surgery evaluating patient reported outcome measures in lumbar spinal stenosis and lumbar degenerative spondylolisthesis.

BACKGROUND: Assessment of outcomes for spinal surgeries is challenging, and an ideal measurement that reflects all aspects of importance for the patients does not exist. Oswestry Disability Index (ODI), EuroQol (EQ-5D) and Numeric Rating Scales (NRS) for leg pain and for back pain are commonly used patients reported outcome measurements (PROMs). Reporting the proportion of individuals with an outcome of clinical importance is recommended. Knowledge of the ability of PROMs to identify clearly improved patients is essential. The purpose of this study was to search cut-off criteria for PROMs that best reflect an improvement considered by the patients to be of clinical importance. METHODS: The Global Perceived Effect scale was utilized to evaluate a clinically important outcome 12 months after surgery. The cut-offs for the PROMs that most accurately distinguish those who reported 'completely recovered' or 'much improved' from those who reported 'slightly improved', unchanged', 'slightly worse', 'much worse', or 'worse than ever' were estimated. For each PROM, we evaluated three candidate response parameters: the (raw) follow-up score, the (numerical) change score, and the percentage change score. RESULTS: We analysed 3859 patients with Lumbar Spinal Stenosis [(LSS); mean age 66; female gender 50%] and 617 patients with Lumbar Degenerative Spondylolisthesis [(LDS); mean age 67; 72% female gender]. The accuracy of identifying 'completely recovered' and 'much better' patients was generally high, but lower for EQ-5D than for the other PROMs. For all PROMs the accuracy was lower for the change score than for the follow-up score and the percentage change score, especially among patients with low and high PROM scores at baseline. The optimal threshold for a clinically important outcome was ≤24 for ODI, ≥0.69 for EQ-5D, ≤3 for NRS leg pain, and ≤ 4 for NRS back pain, and, for the percentage change score, ≥30% for ODI, ≥40% for NRS leg pain, and ≥ 33% for NRS back pain. The estimated cut-offs were similar for LSS and for LDS. CONCLUSION: For estimating a 'success' rate assessed by a PROM, we recommend using the follow-up score or the percentage change score. These scores reflected a clinically important outcome better than the change score.