Aims. People with severe, persistent low back pain (LBP) may be offered lumbar spine fusion surgery if they have had insufficient benefit from recommended non-surgical treatments. However, National Institute for Health and Care Excellence (NICE) 2016 guidelines recommended not offering spinal fusion surgery for adults with LBP, except as part of a randomized clinical trial. This survey aims to describe UK clinicians’ views about the suitability of patients for such a future trial, along with their views regarding equipoise for randomizing patients in a future clinical trial comparing lumbar spine fusion surgery to best conservative care (BCC; the FORENSIC-UK trial). Methods. An online cross-sectional survey was piloted by the multidisciplinary research team, then shared with clinical professional groups in the UK who are involved in the management of adults with severe, persistent LBP. The survey had seven sections that covered the demographic details of the clinician, five hypothetical case vignettes of patients with varying presentations, a series of questions regarding the preferred management, and whether or not each clinician would be willing to recruit the example patients into future clinical trials. Results. There were 72 respondents, with a response rate of 9.0%. They comprised 39 orthopaedic spine surgeons, 17 neurosurgeons, one pain specialist, and 15 allied health professionals. Most respondents (n = 61,84.7%) chose conservative care as their first-choice management option for all five case vignettes. Over 50% of respondents reported willingness to randomize three of the five cases to either surgery or BCC, indicating a willingness to participate in the future randomized trial. From the respondents, transforaminal interbody fusion was the preferred approach for spinal fusion (n = 19, 36.4%), and the preferred method of BCC was a combined programme of physical and psychological therapy (n = 35, 48.5%). Conclusion. This survey demonstrates that there is uncertainty about the role of lumbar spine fusion surgery and BCC for a range of example patients with severe, persistent LBP in the UK. Cite this article: Bone Jt Open 2024;5(7):612–620

Purpose: To develop a regression equation using preoperative variables to predict the likelihood of transfusion intra- or post- operatively for patients undergoing elective spinal fusion surgery. Methods: This study was a retrospective chart review of patients (n=774; 51% female; mean age=56 years; mean BMI=29) who underwent elective spinal fusion surgery between February 2001 and May 2005 at the QEII Health Sciences Centre in Halifax, Nova Scotia. The variables recorded were incidence of allogeneic and autologous transfusions (intra- and post-operatively), body mass index, age, gender, number of spinal levels fused, preoperative hemoglobin and hematocrit, ASA grade and pedicle screw and bone graft use. Results: Spinal fusion of 4 or more levels (n=24) resulted in a transfusion rate of 83%, therefore, the regression equation was calculated using only spinal fusions of 1 to 3 levels (n=750; transfusion rate=14%). The number of spinal levels fused and preoperative hemoglobin levels were found to be significantly related to the likelihood of receiving a transfusion. A predictive logistic regression equation was derived (Prediction = 3.615 + 1.018 x Levels fused–0.052 x Preop Hgb) where a probability cutoff of 0.160 gave a sensitivity of 63.5% and a specificity of 81.2%. Conclusions: The high sensitivity and specificity of the regression equation suggest that the results are clinically useful for determining whether alternatives to allogeneic transfusions should be investigated preoperatively for each patient undergoing elective spinal fusion surgery. The results could also have economic implications because implementing the use of a cell salvage device would be less costly than allogeneic units if the patient required a transfusion

Objectives. We performed a systematic review of the literature to determine the safety and efficacy of bone morphogenetic protein (BMP) compared with bone graft when used specifically for revision spinal fusion surgery secondary to pseudarthrosis. Methods. The MEDLINE, EMBASE and Cochrane Library databases were searched using defined search terms. The primary outcome measure was spinal fusion, assessed as success or failure in accordance with radiograph, MRI or CT scan review at 24-month follow-up. The secondary outcome measure was time to fusion. Results. A total of six studies (three prospective and three retrospective) reporting on the use of BMP2 met the inclusion criteria (203 patients). Of these, four provided a comparison of BMP2 and bone graft whereas the other two solely investigated the use of BMP2. The primary outcome was seen in 92.3% (108/117) of patients following surgery with BMP2. Although none of the studies showed superiority of BMP2 to bone graft for fusion, its use was associated with a statistically quicker time to achieving fusion. BMP2 did not appear to increase the risk of complication. Conclusion. The use of BMP2 is both safe and effective within the revision setting, ideally in cases where bone graft is unavailable or undesirable. Further research is required to define its optimum role. Cite this article: Mr P. Bodalia. Effectiveness and safety of recombinant human bone morphogenetic protein-2 for adults with lumbar spine pseudarthrosis following spinal fusion surgery: A systematic review. Bone Joint Res 2016;5:145–152. DOI: 10.1302/2046-3758.54.2000418

Aims. Psychoeducative prehabilitation to optimize surgical outcomes is relatively novel in spinal fusion surgery and, like most rehabilitation treatments, they are rarely well specified. Spinal fusion patients experience anxieties perioperatively about pain and immobility, which might prolong hospital length of stay (LOS). The aim of this prospective cohort study was to determine if a Preoperative Spinal Education (POSE) programme, specified using the Rehabilitation Treatment Specification System (RTSS) and designed to normalize expectations and reduce anxieties, was safe and reduced LOS. Methods. POSE was offered to 150 prospective patients over ten months (December 2018 to November 2019) Some chose to attend (Attend-POSE) and some did not attend (DNA-POSE). A third independent retrospective group of 150 patients (mean age 57.9 years (SD 14.8), 50.6% female) received surgery prior to POSE (pre-POSE). POSE consisted of an in-person 60-minute education with accompanying literature, specified using the RTSS as psychoeducative treatment components designed to optimize cognitive/affective representations of thoughts/feelings, and normalize anxieties about surgery and its aftermath. Across-group age, sex, median LOS, perioperative complications, and readmission rates were assessed using appropriate statistical tests. Results. In all, 65 (43%) patients (mean age 57.4 years (SD 18.2), 58.8% female) comprised the Attend-POSE, and 85 (57%) DNA-POSE (mean age 54.9 years (SD 15.8), 65.8% female). There were no significant between-group differences in age, sex, surgery type, complications, or readmission rates. Median LOS was statistically different across Pre-POSE (5 days ((interquartile range (IQR) 3 to 7)), Attend-POSE (3 (2 to 5)), and DNA-POSE (4 (3 to 7)), (p = 0.014). Pairwise comparisons showed statistically significant differences between Pre-POSE and Attend-POSE LOS (p = 0.011), but not between any other group comparison. In the Attend-POSE group, there was significant change toward greater surgical preparation, procedural familiarity, and less anxiety. Conclusion. POSE was associated with a significant reduction in LOS for patients undergoing spinal fusion surgery. Patients reported being better prepared for, more familiar, and less anxious about their surgery. POSE did not affect complication or readmission rates, meaning its inclusion was safe. However, uptake (43%) was disappointing and future work should explore potential barriers and challenges to attending POSE. Cite this article: Bone Jt Open 2022;3(2):135–144

The risk of blood transfusion in spinal fusion surgery is significant and mandates efforts to reduce ABT. This prospective study demonstrated a significant reduction in the rate of allogeneic blood transfusion (ABT) using Cell Saver (CS), Preoperative Autologus Donation (PAD), and Preoperative Erythropoietin Therapy (PET). The ABT was inversely related to the number of modalities used: 74% (n=14/19) with zero modalities; 32% (n=24/74) with one modalities; 17% (n=9/52) with two modalities; and 7% (n=2/28) with three modalities. Due to the potential amount of blood loss during spinal fusions the use of several BC techniques in combination is required to effectively reduce ABT. The purpose of this prospective study is to assess the efficacy of current blood conservation (BC) techniques in reducing the rate of allogeneic blood transfusion (ABT) in spinal fusions. All three current blood conservation techniques, particularly in combination, proved to be very effective in reducing the rate of ABT in elective spinal fusions. Transfusion of allogenic blood despite its improved safety is not without risk. From June 1999 to September 2001, transfusion and related surgical data has been prospectively collected in one hundred and seventy-three patients undergoing elective spinal fusions. The following three BC techniques were utilized: Cell Saver (CS), Preoperative Auto-logus Donation (PAD), and Preoperative Erythropoietin Therapy (PET). The average number of fusion levels was 2.3 (range 1–5). The average estimated blood loss was 1725 milliliters (range 250–10700). Decompression was also preformed in 75% of cases. The overall ABT rate was 28% (n=49/173). The ABT was inversely related to the number of modalities used: 74% (n=14/19) with zero modalities; 32%* (n=24/74) with one modalities; 17%* (n=9/52) with two modalities; and 7%*† (n=2/28) with three modalities respectively (*statistically significant compared to zero modality group; † statistically significant compared to one modality group). The patient demographics and surgical variables were similar between the four groups. The use of CS, PAD, and PET was independently related to ABT. The risk of blood transfusion in spinal fusion surgery is significant and mandates efforts to reduce ABT. Due to the amount of blood loss the use of several BC techniques in combination is required to effectively reduce ABT

This study aims to explore the trend in spine fusion surgery in Australia over the past 10 years and to explore the possible influence of health insurance status (private versus public) on the rate of surgery. Data pertaining to the rate of lumbar spine fusion from 1997 to 2006 were collected. Data on publicly performed procedures in NSW were obtained from Inpatient Statistics Collection of NSW Health, and data on privately performed procedures were obtained from Medicare Australia Statistics. Population data was obtained from the Australian Bureau of Statistics. Data on total hip and total knee arthroplasties performed were collected to provide a comparator. Health insurance coverage was also investigated to control for insurance status, this data was obtained from the Private Health Insurance Administration Council. There has been a slowly declining trend in the number of publicly performed spinal fusion procedures over the past 10 years, falling by 63% from 1997 to 2006 in NSW. In comparison, privately performed spinal fusion procedures have increased by 166% over the same 10 year period. Compared to spine fusion, the rates of total hip and total knee replacement procedures in the public sector of NSW have fallen by smaller proportions (58.9%% and 42.1%, respectively) over the same 10 year period. The increase in privately performed joint replacements has been less than that seen for spine fusion, with increases of 120% and 74%% for knee arthroplasties and hip arthroplasties, respectively. In 2006, spine fusion surgery was 10.8 times more likely to be done in the private sector than in the public sector, compared to corresponding figures of 4.2 times and 3.0 times for knee replacement and hip replacement, respectively. Our study has demonstrated that there is a disproportionately high rate of spine fusion procedures performed in the private sector. Possible explanations for this difference include: over servicing in the private sector, under servicing in the public sector, differences in medical referral patterns, surgeon and patient preferences, and financial incentives

Introduction. Periprosthetic infections are leading causes of revision surgery resulting in significant increased patient comorbidities and costs. Considerable research has targeted development of biomaterials that may eliminate implant-related infections. 1. This in vitro study was developed to compare biofilm formation on three materials used in spinal fusion surgery – silicon nitride, PEEK, and titanium – using one gram-positive and one gram-negative bacterial species. Materials and Methods. Several surface treated silicon nitride (Si. 3. N. 4. , MC2. ®. , Amedica Corporation, Salt Lake City, UT), poly-ether-ether-ketone (PEEK, ASTM D6262), and medical grade titanium (Ti6Al4V, ASTM F136) discs Ø12.7 × 1mm were prepared or acquired for use in this well-plate study. Each group of discs (n=3) were ultrasonically cleaned, UV-sterilized, inoculated with 10. 5. Staphylococcus epidermidis (ATCC. ®. 25922™) or Escherichia coli (ATCC. ®. 14990™) and placed in a culture medium of phosphate buffered saline (PBS) containing 7% glucose and 10% human plasma on a shaking incubator at 37°C and 120 rpm for 24 or 48 hrs. Coupons were retrieved, rinsed in PBS to remove planktonic bacteria, placed in a centrifuge with fresh PBS, and vortexed. The bacterial solutions were serially diluted, plated, and incubated at 37°C for 24 to 48 hrs. Colony forming units (CFU/mm. 2. ) were counted using applicable dilution factors and surface areas. A two-tailed, heteroscedastic Student's t-test (95% confidence) was used to determine statistical significance. Results. Biofilm adhesion results are provided in Figures 1 and 2 for S. epi. and E. coli, respectively. For S. epi. at 24 hrs, biofilm growth on PEEK was about three orders of magnitude greater than on Ti6Al4V or any Si. 3. N. 4. material (all p<0.005). Ti6Al4V also had more bacteria than the Si. 3. N. 4. samples, but was only significant for as-fired and nitrogen-annealed treatments. Similar trends and significance for S. epi. were observed at 48 hrs. For E. coli, biofilm formation on PEEK was significantly greater than all other materials at both 24 and 48 hrs. Bacterial growth on Ti6Al4V was also statistically greater than all Si. 3. N. 4. conditions, with the possible exception of nitrogen-annealed Si. 3. N. 4. By 48 hrs, PEEK remained 2 orders of magnitude above Ti6Al4V, and 2.5–3 orders of magnitude greater than the Si. 3. N. 4. conditions. Ti6Al4V was also significantly greater than all of the Si. 3. N. 4. treatments at 48 hrs. Discussion. Si. 3. N. 4. , PEEK, and Ti6Al4V surfaces demonstrated significant differences in bacterial adhesion and proliferation for both gram-positive S. epi. and gram-negative E. coli, particularly at 48 hrs post-inoculation. The various Si. 3. N. 4. samples showed the most favorable bacterial resistance for both species tested. The exact mechanism of the bacteriostatic behavior of Si. 3. N. 4. is still under investigation; but it may result from chemical interaction with the material's surface to form peroxynitrite (a powerful oxidative agent). 2. Conclusion. Identifying biomaterial surfaces that resist biofilm adhesion is an important emerging strategy in addressing implant-related infections. Si. 3. N. 4. is a new biomaterial with the apparent potential to suppress biofilm formation

Introduction: Spinal fusions have been shown to be useful in correcting spinal deformities resulting from degenerative disc disease. We sought to produce a prospective analysis of functional outcomes following lumbar spinal fusion surgery for degenerative spondylolisthesis or degenerative scoliosis secondary to degenerative disc disease. We present the interim results from our case cohort of 74 patients. Methods: Over a period of 3 years (2005–2007), all patients who presented to this private practice with symptoms of canal stenosis or radicular pain secondary to degenerative spondylolisthesis or degenerative scoliosis were offered decompressive laminectomy and posterior lumbar interbody fusion (PLIF) surgery with interbody cages, pedicle screw instrumentation, bone morphogenic protein (BMP) and bicalcium phosphate (BCP). Patients who presented only with low back pain and did not have radicular pain or neurogenic claudication were excluded from this study. All patients who were offered spinal fusion surgery were consecutively offered the opportunity to enrol in this functional cohort analysis. Those patients who consented were prospectively entered into this functional analysis and were asked to complete Oswestry and SF-36 function questionnaires preoperatively and post-operatively. Post-operative data has been collected in some cases up to 16 months postoperatively. Patients were also assessed post-operatively by the surgeon and given an Odom clinical assessment score. Complications were also collated. Results: 102 patients were offered surgery with 18 patients not consenting to participate in this study. Of the 84 patients who consented to participate in this study, 10 patients failed to submit both pre-operative and postoperative questionnaires, leaving 74 patients who were followed for a median 7 months (range of 1.5–16 months). There were 30 males and 44 females in the study with a median age of 73 (range 46–89). Of these 74 patients, 63 had degenerative spondylolisthesis and 11 had degenerative scoliosis. 52 patients had sufficient follow-up to assess bony fusion, of which 1 patient failed to fuse. 32 of the patients who fused reported to have improved, but 16 did not and the remainder did not submit both pre-operative and post-operative questionnaires. For the SF-36 questionnaire, the median pre-operative SF-36 score was 30 (96.6% CI 26–35) and the median post-operative SF-36 score was 48 (95.3% CI 42–56). The mean difference between the preoperative and post-operative SF-36 scores was 14 (95% CI 11–18) (p< 0.0001. The median preoperative Oswestry score was 46 (96.6% CI 42–50) and the median post-operative Oswestry score was 30 (96.6% CI 24–40) and the median post-operative Oswestry score was 30 (96.6% CI 24–40). The mean difference between the preoperative and post-operative Oswestry scores was 14 (95% CI 10–19) (p= 0.0001). 45 patients (61%) reported improvements of greater than 20 between their pre-operative and post-operative scores in either their SF-36 or Oswestry questionnaires. Of these 45 patients, 40 (89%) were also given moderate or good Odom (clinical) scores. 29 patients (39%) reported that they had not experienced improvement in their symptoms based on either their SF-36 or Oswestry questionnaires, with 12 (41%) of those 29 patients scoring poorly on their Odom scores. In all, there were 18 complications ranging from wound collections (4) and breakdowns (2) to repositioning of screws (6) and nerve root injury (2), to DVT (1) and transfusion (3). Discussion: Interim results suggest that most patients undergoing PLIF and pedicle screw surgery with decompressive laminectomy for treatment of degenerative spondylolisthesis and degenerative scoliosis report significant improvements in function which correlate fairly well with clinical assessments performed by the surgeon at pre-operative and post-operative reviews. IInterestingly, patients generally reported either significant improvements (rather than borderline improvements) or that they had not improved at all, and that those who did report significant improvements also generally scored well on their Odom assessments. These reported improvements currently seem to be independent of whether bony fusion is achieved or not, as 16 of the 29 patients who did not report improvement actually achieved fusion. This is not unexpected as the initial PLIF procedure provides initial pre-fusion in situ rigid internal fixation

Background and Purpose

The UK's NIHR and Australia's NHMRC have funded two randomised controlled trials (RCTs) to determine if lumbar fusion surgery (LFS) is more effective than best conservative care (BCC) for adults with persistent, severe low back pain (LBP) attributable to lumbar spine degeneration. We aimed to describe clinicians’ decision-making regarding suitability of patient cases for LFS or BCC and level of equipoise to randomise participants in the RCTs.

Very few reports exist regarding use of intra-operative autologenous transfusion in adult spinal fusion surgery. Specific indications for use of cell saver in thoraco-lumbar spinal instrumentation are not clearly determined. Our objective was to identify the clinical factors associated with increased risk of intra-operative blood loss. To analyse the safety and benefits of using cell saver and to determine the cost-effectiveness. 51 consecutive thoraco-lumbar instrumented fusion over 14 months reviewed. There was no randomisation. Cell saver group consisted of 25 patients and control group consisted of 26 cases. Patients with degenerative scoliosis and tumours excluded. Clinical notes were reviewed. Demographic data were comparable between the two groups. Iliac crest bone graft harvested in 20% of cell saver group and 40% in control group. Levels of fusion ranged from 1–7 (Mean=2.8) in the cell saver group and 1–4 (Mean=1.9) in the control group. Mean duration of surgery was 15 minutes longer in study group. Intra-operative blood loss was higher in cell saver group (mean=1245 mls vs 800 mls). Significant indicators for duration of surgery were number of levels fused (p< 0.0001), patient weight (p=0.003) and revision surgery (p=0.029). Significant indicators for predicting blood loss were number of levels fused (p< 0.001) and duration of surgery (p=0.0304). 20% in study group (8 units of red cells) and 26% in control group (17 units of red cells) required blood transfusion. Percentage drop in the post-operative haematocrit was 19.1 in study group compared to 36.3 in control group. In conclusion, 44.38% blood salvaged (35–38% in spinal literature). Use of cell saver significantly decreased post-operative need for blood transfusion. Number of levels of fusion, duration greater than 4 hrs and a low pre-op Haemoglobin/Haematocrit were significant parameters in predicting intra-operative blood loss. If blood loss is less than 700 mls, gains from cell saver are debatable

Introduction

Both intra- and post-operative radiographs are traditionally obtained after instrumented lumbar spinal surgery; however the clinical advantage of routine post operative images has not been demonstrated.

Background: Cell Saver technique using intra-operative autologenous transfusion known to conserve homologous blood resources.

Specific indications for use of cell saver in thoracolumbar spinal instrumented fusion not clearly determined.

No previously published literature from Britain to our knowledge.

Objectives: To identify the clinical factors associated with increased risk of intra-operative blood loss.

To analyse the safety and benefits of using cell saver technique.

Method: A total of 51 consecutive spinal instrumented fusion cases during last 14 months reviewed.

There was no randomisation; use of cell saver was at surgeon’s discretion.

Results: Demographic data including age, weight, smoking and prior surgery were similar between the two groups.

Iliac crest bone graft harvested in 20% of cell saver group and 40% in control group.

Conclusion: 44.38% blood salvaged (35–38% in spinal literature).

Use of cell saver significantly decreased the risk of post-operative need for blood transfusion.

Introduction: Recombinant human bone morphogenic protein-2 (rhBMP-2) eliminates the need for iliac crest bone graft and has superior fusion rates in anterior interbody fusion1. Post-operative neck swelling has precluded its use in cervical fusion2. Peri-rhBMP-2 oedema is a proposed cause of neuropathic leg pain in posterolateral lumbar fusion. We aimed to compare the incidence of leg pain in a rhBMP-2 treated cohort with a control group following posterolateral lumbar fusion and to determine radiological evidence of a mechanical cause for leg pain in either group.

Methods and Results: A single surgeon, multi-centre elective practice was retrospectively reviewed over a four-year period. All rhBMP-2 treated patients were included. Control patients included all primary instrumented lumbar fusions. Endpoints included single observer recorded leg pain. There were 64 and 40 patients in the rhBMP-2 treated and control group respectively. Pre-operative demographics and diagnoses were similar. Inter-body cages were used equally. Three patients had non-mechanical leg pain in the control group versus eleven in the rhBMP-2 group of which 6 were revision surgeries. None of the control group had previous lumbar fusion (p< 0.05). Within the rhBMP-2 group, cage use was similar for leg pain (31%) and non-leg pain (29%).

Conclusion: In primary lumbar fusion surgery, there is no significant difference in post-operative MRI-identifiable mechanical leg pain between rhBMP-2 treated and non-treated groups. RhBMP-2 loaded cages do not increase the risk of leg pain. Recombinant hBMP-2 is safe to use in posterolateral lumbar surgery.

Conflicts of Interest: None

Source of Funding: None

Surgical site infections (SSIs) after spinal fusion surgery increase healthcare costs, morbidity and mortality. Routine measures of obesity fail to consider site specific fat distribution. We aimed to assess the association between the spine adipose index and deep surgical site infection and determine a threshold value for spine adipose index that can assist in preoperative risk stratification in patients undergoing posterior instrumented lumbar fusion (PILF). A multicentre retrospective case-control study was completed. We reviewed patients who underwent PILF from January 1, 2010 to December 31, 2018. All patients developing a deep primary incisional or organ-space SSI within 90 days of surgery as per US Centre for Disease Control and Prevention criteria were identified. We gathered potential pre-operative and intra-operative deep infection risk factors for each patient. Spine adipose index was measured on pre-operative mid-sagittal cuts of T2 weighted MRI scans. Each measurement was repeated twice by three authors in a blinded fashion, with each series of measurement separated by a period of at least six weeks. Forty-two patients were included in final analysis, with twenty-one cases and twenty-one matched controls. The spine adipose index was significantly greater in patients developing deep SSI (p =0.029), and this relationship was maintained after adjusting for confounders (p=0.046). Risk of developing deep SSI following PILF surgery was increased 2.0-fold when the spine adipose index was ≥0.51. The spine adipose index had excellent (ICC >0.9; p <0.001) inter- and intra-observer reliabilities. The spine adipose index is a novel radiographic measure and an independent risk factor for developing deep SSI, with 0.51 being the ideal threshold value for pre-operative risk stratification in patients undergoing PILF surgery

Hip instability is one of the most common causes for total hip arthroplasty (THA) revision surgery. Studies have indicated that lumbar fusion (LF) surgery is a risk factor for hip dislocation. Instrumented spine fusion surgery decreases pelvic tilt, which might lead to an increase in hip motion to accommodate this postural change. To the best of our knowledge, spine-pelvis-hip kinematics during a dynamic activity in patients that previously had both a THA and LF have not been investigated. Furthermore, patients with a combined THA and LF tend to have greater disability. The purpose was to examine spine-pelvis-hip kinematics during a sit to stand task in patients that have had both THA and LF surgeries and compare it to a group of patients that had a THA with no history of spine surgery. The secondary purpose was to compare pain, physical function, and disability between these patients. This cross-sectional study recruited participants that had a combined THA and LF (n=10; 6 females, mean age 73 y) or had a THA only (n=11; 6 females, mean age 72 y). Spine, pelvis, and hip angles were measured using a TrakSTAR motion capture system sampled at 200 Hz. Sensors were mounted over the lateral thighs, base of the sacrum, and the spinous process of the third lumbar,12th thoracic, and ninth thoracic vertebrae. Participants completed 10 trials of a standardized sit-to-stand-to-sit task. Hip, pelvis, lower lumbar, upper lumbar, and lower thoracic sagittal joint angle range of motion (ROM) were calculated over the entire task. In addition, pain, physical function, and disability were measured with clinical outcomes: Hip Disability Osteoarthritis Outcome Score (pain and physical function), Oswestry Low Back Disability Questionnaire (disability), and Harris Hip Score (pain, physical function, motion). Physical function performance was measured using 6-Minute Walk Test, Stair Climb Test, and 30s Chair Test. Angle ROMs during the sit-to-stand-to-sit task and clinical outcomes were compared between THA+LF and THA groups using independent t-tests and effect sizes (d). The difference in hip ROM was approaching statistical significance (p=0.07). Specifically, the THA+LF group had less hip ROM during the sit-to-stand-to-sit task than the THA only group (mean difference=11.17, 95% confidence interval=-1.13 to 23.47), which represented a large effect size (d=0.83). There were no differences in ROM for pelvis (p=0.54, d=0.28) or spinal (p=0.14 to 0.97; d=0.02 to 0.65) angles between groups. The THA+LF group had worse clinical outcomes for all measures of pain, physical function, and disability (p=0.01 to 0.06), representing large effect sizes (d=0.89 to 2.70). Hip ROM was not greater in the THA+LF group, and thus this is unlikely a risk factor for hip dislocation during this specific sit-to-stand-to-sit task. Other functional tasks that demand greater excursions in the joints should be investigated. Furthermore, the lack of differences in spinal and pelvis ROM were likely due to the task and the THA+LF group had spinal fusions at different levels. Combined THA+LF results in worse clinical outcomes and additional rehabilitation is required for these patients

AO Spine Guideline for Using Osteobiologics in Spine Degeneration project is an international collaborative initiative to identify and evaluate evidence on existing use of osteobiologics in spine degenerative diseases. It aims to formulate clinically relevant and internationally applicable guidelines ensuring evidence-based, safe and effective use of osteobiologics. The current focus is the use of osteobiologics in anterior cervical discectomy and fusion surgeries. The guideline development is planned in three phases. Phase 1- Evidence synthesis and Recommendation; Phase 2- Guideline with osteobiologics grading and Validation; Phase 3- Guideline dissemination and Development of a clinical decision support tool. The key questions formulating the guidelines for the use of osteobiologics will be addressed in a series of systematic reviews in Phase 1. The evidence synthesized by the systematic reviews will be assessed by Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology, including expert panel discussions to formulate a recommendation. In Phase 2, osteobiologics will be graded based on evidence and the grading will be integrated with the recommendation from Phase 1, and thus formulate a guideline. The guideline will be further validated by prospective clinical studies. In the third phase, dissemination of the proposed guideline and development of a decision support tool is planned. AO-GO aims to bridge an important gap between quality of evidence and use of osteobiologics in spine fusion surgeries. With a holistic approach the guideline aims to facilitate evidence-based, patient-oriented decision-making process in clinical practice, thus stimulating further evidence-based studies regarding osteobiologics usage in spine surgeries

Introduction Disc replacement surgery is being investigated as an alternative to spinal fusion surgery in the hope that maintaining segment spinal motion will not only relieve pain, but also prevent or reduce the likelihood of symptomatic adjacent segment degeneration that is believed to be a consequence of fusion surgery. The aim of this study was to identify evidence in the medical literature that indicates whether or not spinal fusion surgery increases the likelihood of symptomatic adjacent segment degeneration compared to disc replacement surgery or natural history. Methods A search of the Cochrane Controlled Trials Register, Medline and reference lists of retrieved articles was performed. Search terms included arthroplasty replacement, spinal fusion, prognosis, controlled clinical trials and cohort studies, Studies were included if abstracts were available electronically, were published in the English language before1/3/2005 and involved humans. Levels of evidence were determined using the Oxford Centre for Evidence-Based Medicine criteria (. http://www.cebm.net/levels of evidence.asp. ). Discussion The majority of identified studies were case series of patients presenting with adjacent level disc degeneration following spinal fusion surgery (Level 4) and whilst indicating patients can develop adjacent level disc degeneration following fusion surgery, do not indicate the likelihood of doing so. Uncontrolled prospective cohort studies (Level 4) provide conflicting evidence. One retrospective cohort (Level 2b) studying comparing the incidence of adjacent disc degeneration following spinal fusion and discectomy or decompressive surgery alone found that the incidence of degeneration in the superior adjacent disc was increased in the fusion group, but was not associated with differences in functional outcome. No systematic reviews of inception cohort studies (Level 1) were identified. Conclusions Only poor quality evidence has been published to support the proposition that spinal fusion surgery is associated with an increased likelihood of developing symptomatic adjacent level disc degeneration. Long term follow-up of patients enrolled in prospective randomised controlled trials comparing outcomes of spinal fusion and disc replacement surgery is necessary to determine whether or not disc replacement surgery decreases the likelihood of any symptomatic adjacent level disc degeneration that can be attributed to spinal fusion surgery

Complications after spinal fusion surgery are common, with implant loosening occurring in up to 50% of osteoporotic patients. Pedicle screw fixation strength reduces as a result of decreased trabecular bone density, whereas sublaminar wiring is less affected by these changes. Therefore, pedicle screw augmentation with radiopaque sublaminar wires (made with Dyneema Purity® Radiapque fibers, DSM Biomedical, Geleen, the Netherlands) may improve fixation strength. Furthermore, sublaminar tape could result in a gradual motion transition to distribute stress over multiple levels and thereby reduce implant loosening. The objective of this study is to test this hypothesis in a novel experimental setup in which a cantilever bending moment is applied to individual human vertebrae. Thirty-eight human cadaver vertebrae were stratified into four different groups: ultra-high molecular weight polyethylene sublaminar tape (ST), pedicle screw (PS), metal sublaminar wire (SW) and pedicle screw reinforced with sublaminar tape (PS+ST). The vertebrae were individually embedded in resin, and a cantilever bending moment was applied bilaterally through the spinal rods using a universal material testing machine. This cantilever bending setup closely resembles the loading of fixators at transitional levels of spinal instrumentation. The pull-out strength of the ST (3563 ± 476N) was not significantly different compared to PS, SW or PS+ST. The PS+ST group had a significantly higher pull-out strength (4522 ± 826N) compared to PS (2678 ± 292N) as well as SW (2931 ± 250N). The higher failure strength of PS + ST compared to PS indicates that PS augmentation with ST may be an effective measure to reduce the incidence of screw pullout, even in osteoporotic vertebrae. Moreover, the lower stiffness of sublaminar fixation techniques and the absence of damage to the cortices in the ST group suggest that ST as a stand-alone fixation technique in adult spinal deformity surgery may also be clinically feasible and offer clinical benefits

Proximal junctional kyphosis (PJK) is defined as adjacent segment kyphosis >10° between the upper instrumented vertebrae and the vertebrae 2 levels above following scoliosis surgery. There are few studies investigating the predictors and clinical sequelae involved with this relatively common complication. Our purpose was to determine the radiographic predictors of post-op PJK and to examine the association between PJK and pain/HRQOL following surgery for AIS. The Post-Operative Recovery after Scoliosis Correction: Home Experience (PORSCHE) study was a prospective multicenter cohort of AIS patients undergoing spinal fusion surgery. Pre-op and minimum 2 year f/u scoliosis and sagittal spinopelvic parameters (thoracic kyphosis–TK, lordosis–LL, pelvic tilt-PT, sacral slope-SS, pelvic incidence-PI) were measured and compared to numeric rating scale for pain (NRS) score, SRS-30 HRQOL and to the presence or absence of PJK (proximal junctional angle >100). Continuous and categorical variables were assessed using logistic regression and binomial variables were compared to binomial outcomes using chi-square. 163 (137 females) patients from 8 Canadian centers met inclusion criteria. At final f/u, PJK was present in 27 patients (17%). Pre-op means for PJK vs No PJK: Age 14.1 vs 14.7yr; females 85 vs 86%; scoliosis 57±22 vs 62±15deg; TK 28±18 vs 19±16deg ∗, LL 62±11 vs 60±12deg, PT 8±12 vs 10±10deg, SS 39±8 vs 41±9deg, PI 47±14 vs 52±13deg, SVA −9±30 vs −7±31mm. Final f/u for PJK vs No PJK: Scoliosis 20±11 vs 18±8deg, final TK 26±12 vs 19±10deg∗, LL 60±11 vs 57±12deg, PT 9±12 vs 12±13deg, SS 39±9 vs 41±9deg, PI 48±17 vs 52±14deg, SVA −23±26 vs −9±32mm∗. Significant findings: Pre-op kyphosis >40deg has an odds ratio (OR) of 4.41 (1.50–12.92) for developing PJK∗. The presence of PJK was not associated with any significant differences in NRS or SRS-30. ∗denotes p<0.05. This prospective multicenter cohort of AIS patients demonstrated a 17% risk of developing PJK. Pre-op thoracic kyphosis >40deg was associated with the development of PJK; however, the presence of PJK was not associated with increased pain or decreased HRQOL

Low back pain is more common in women than men, yet most studies of intervertebral disc (IVD) degeneration do not address sex differences. In humans, there are sex differences in spinal anatomy and degenerative changes in biomechanics, and animal models of chronic pain have demonstrated sex differences in pain transduction. However, there are few studies investigating sex differences in annular puncture IVD degeneration models. IVD puncture is known to result in progressive biomechanical alterations, but whether these IVD changes correlate with pain is unknown. This study used a rat IVD injury model to determine if sex differences exist in mechanical allodynia, biomechanics, and the relationship between them, six weeks after IVD injury. Procedures were IACUC approved. 24 male & 24 female four-month-old Sprague-Dawley rats underwent a sham or annular puncture injury surgery (n=12 male, 12 female). In injury groups, three lumbar IVDs were each punctured three times with a needle, and injected with tumor necrosis factor-alpha. Mechanical allodynia was tested biweekly using von Frey filaments. Six weeks after IVD injury, rats were euthanized and motion segments were dissected for non-destructive axial tension-compression and torsional rotation biomechanical testing. Two-way ANOVA with Bonferroni corrections identified statistically significant differences (p < 0 .05) and correlations used Pearson's coefficient. Annular puncture injury induced a significant increase in mechanical allodynia compared to sham in male but not female rats up to six weeks after injury. There was a significant sex effect on both torque range and torsional stiffness, with males exhibiting greater stiffness and torque range than females. Tensile stiffness, compressive stiffness, and axial range of motion showed no sex difference. Males and females showed similar patterns of correlation between variables when sham and injury groups were analyzed together, but correlations were stronger in males. Most correlations were clustered within testing approach: axial biomechanics negatively correlated, torsional biomechanics positively correlated, and von Frey thresholds positively correlated. Surprisingly, mechanical allodynia did not correlate with any biomechanics after injury, and the axial and torsional biomechanics showed little correlation. This study demonstrates that males and females respond to IVD injury differently. Given the absence of correlation between pain and biomechanics, pain cannot be attributed completely to biomechanical changes. This may explain why spinal fusion surgery, an intervention limited to the spine, has produced inconsistent results and is controversial for patients with low back pain. Thus, in addressing low back pain, we must consider both spinal tissues and the nervous system. Further, the limited correlation between axial and torsional biomechanics indicates that IVD injury may have distinct effects on nucleus pulposus and annulus fibrosus. Biomechanics did not differ between sham and injury at week six, suggesting healing after injury. It remains possible that acute biomechanical changes may initiate chronic pain pathogenesis. We conclude that the observed sex differences demonstrate the need for inclusion of both males and females in IVD injury and pain studies, and suggest that males and females may require different treatments for conditions that appear similar