Introduction:. Circumferential arthrodesis of the spine may be achieved by posterior-only or anterior and posterior surgery. Posterior-based interbody fusions have significant limitations including unreliable improvement of segmental lordosis and variable rates of post-operative radiculopathy. Combined anterior and posterior surgery introduces significant cost and peri-operative morbidity. The purpose of this paper is to report the radiographic and clinical outcomes of posterior-based circumferential arthrodesis using a novel expandable interbody cage. Methods:. A prospective pilot clinical trial with one year follow-up of the only expandable cage approved by the FDA for interbody application. Clinical outcomes measured include ODI and VAS for back and leg. Radiographic outcomes include arthrodesis rates based upon CT scan. Statistical significance for change in health status was calculated using Student's t-test. Results:. 10 consecutive patients (11 levels) with lumbar degenerative pathology underwent circumferential arthrodesis with a transforaminal interbody approach. 10 of 11 levels were fused based upon CT scan. ODI scores improved a median of 37 to 20 at 6 months and 17 at one year (p = 0.0003). The VAS for back and leg pain likewise from 6 to 2 at 12 months (p = −.003). No patient reported an increase in leg pain from pre-op to post-op. One patient with a 2-level fusion had a non-union at 1 level requiring revision surgery. Conclusion:. Circumferential arthrodesis with a TLIF approach is an important technique for the management of lumbar degenerative pathology. The experience with a novel expandable TLIF cage demonstrates excellent results based upon clinical outcome and fusion rates. The expandable interbody cage allows in-situ height increase which is useful for optimizing clinical and radiographic outcomes in TLIF surgery

Summary. In this study, OsteoAMP® bone graft showed superior fusion rates as compared to rhBMP-2 at all timepoints (p<0.004). Additionally, OsteoAMP® bone graft had >80% few adverse events as compared to rhBMP-2. Introduction. Adverse events and complications related to use of rhBMP-2 have raised many ethical, legal, and reimbursement concerns for surgeons. OsteoAMP® bone graft is an allograft derived growth factor, rich in osteoinductive, angiogenic, and mitogenic proteins. The following data displays a blinded, multi -center study evaluating and comparing fusion outcomes between rhBMP-2 and OsteoAMP® bone graft. Patients & Methods. A total of 254 consecutive patients (383 total levels) were treated with TLIF or LLIF spine fusion procedures. A group of 70 patients (53.3 ± 11.1 y/o) were treated with rhBMP-2 (Infuse®/Inductos®, Medtronic) and local bone inside of a PEEK interbody cage with an average of 1.44 levels per surgery. A group of 184 patients (60.5 ± 13.1 y/o) were treated with OsteoAMP® (Advanced Biologics) and local bone inside of a PEEK interbody cage with an average of 1.53 levels per surgery. Fusion assessments were made by a blinded independent radiologist based on radiograph and CT images at 6w, 3m, 6m, 12m, and 18m follow up. Radiographically evident adverse events were also assessed in a blinded manner by an independent radiologist. Results. Overall fusion analysis showed superiority in efficacy of OsteoAMP® over rhBMP-2 at all time points (p<0.004). Use of rhBMP-2 produced limited early fusions at 6 months (22.7%) yet improved at 1 year (71.4%). OsteoAMP® facilitated fusion for the majority of patients by 6 months (54.1%) and nearly all patients within 1 year (93.9%). At 18 months, 99.3% of OsteoAMP® patients had fused while the rhBMP-2 arm had an 86.7% fusion rate. Total time for fusion for OsteoAMP® was approximately half that of rhBMP-2 at 211.4 days and 407.1 days respectively. A subset cohort of 47 patients in the rhBMP-2 arm had OsteoAMP® packed anterior to the PEEK cage. When OsteoAMP® was used as an extender to rhBMP-2 in this manner, fusion rates increased at all timepoints (p=0.05 at 18 months) over patients that only had rhBMP-2 and local bone within the disc space. Though, the fusion rates of OsteoAMP® without rhBMP-2 remained higher than the rhBMP-2/local bone/OsteoAMP® extender cohort at all timepoints (p<0.05). To further isolate the effect of OsteoAMP, a subset cohort of 52 patients within the OsteoAMP® treatment arm in the absence of rhBMP-2 did not utilise bone marrow aspirate. The fusion rates of patients within this cohort was statistically higher at 6 months but did not show statistically higher fusion rates at 3 months, 12 months, or 18 months (p>0.12). When compared to the rhBMP-2 study arm, patients within the OsteoAMP® arm that did not receive bone marrow aspirate demonstrated higher fusion rates at all time points (p<0.04 at 12 and 18 months). The rhBMP-2 arm had more than 5 times the incidence of radiologically evident adverse events (osteolysis and ectopic bone formation) compared to the OsteoAMP® arm (43.3% vs. 8.2%, respectively). Discussion. Despite its use with an older patient population and a higher number of levels per surgery, OsteoAMP® has shown great promise as a faster and safer alternative to rhBMP-2 in lumbar spine surgery

Obesity is an increasing public health concern associated with increased perioperative complications and expense in lumbar spine fusions. While open and mini-open fusions such as transforaminal lumbar interbody fusion (TLIF) and minimally invasive TLIF (MIS-TLIF) are more challenging in obese patients, new MIS procedures like oblique lateral lumbar interbody fusion (OLLIF) may improve perioperative outcomes in obese patients relative to TLIF and MIS-TLIF. The purpose of this study is to determine the effects of obesity on perioperative outcomes in OLLIF, MIS-TLIF, and TLIF. This is a retrospective cohort study. We included patients who underwent OLLIF, MIS-TLIF, or TLIF on three or fewer spinal levels at a single Minnesota hospital after conservative therapy had failed. Indications included in this study were degenerative disc disease, spondylolisthesis, spondylosis, herniation, stenosis, and scoliosis. We measured demographic information, body mass index (BMI), surgery time, blood loss, and hospital stay. We performed summary statistics to compare perioperative outcomes in MIS-TLIF, OLLIF, and TLIF. We performed multivariate regression to determine the effects of BMI on perioperative outcomes controlling for demographics and number of levels on which surgeries were operated. OLLIF significantly reduces surgery time, blood loss, and hospital stay compared to MIS-TLIF, and TLIF for all levels. MIS-TLIF and TLIF do not differ significantly except for a slight reduction in hospital stay for two-level procedures. On multivariate analysis, a one-point increase in BMI increased surgery time by 0.56 ± 0.47 minutes (p = 0.24) in the OLLIF group, by 2.8 ± 1.43 minutes (p = 0.06) in the MIS-TLIF group, and by 1.7 ± 0.43 minutes (p < 0.001) in the TLIF group. BMI has positive effects on blood loss for TLIF (p < 0.001) but not for OLLIF (p = 0.68) or MIS-TLIF (p = 0.67). BMI does not have significant effects on length of hospital stay for any procedure. Obesity is associated with increased surgery time and blood loss in TLIF and with increased surgery time in MIS-TLIF. Increased surgery time may be associated with increased perioperative complications and cost. In OLLIF, BMI does not affect perioperative outcomes. Therefore, OLLIF may reduce the disparity in outcomes and cost between obese and non-obese patients

Introduction and Objective. Posterior and transforaminal lumbar interbody fusion (PLIF, TLIF) represent the most popular techniques in performing an interbody fusion amongst spine surgeons. Pseudarthrosis, cage migration, subsidence or infection can occur, with subsequent failed surgery, persistent pain and patient’ bad quality of life. The goal of revision fusion surgery is to correct any previous technical errors avoiding surgical complications. The most safe and effective way is to choose a naive approach to the disc. Therefore, the anterior approach represents a suitable technique as a salvage operation. The aim of this study is to underline the technical advantages of the anterior retroperitoneal approach as a salvage procedure in failed PLIF/TLIF analyzing a series of 32 consecutive patients. Materials and Methods. We performed a retrospective analysis of patients’ data in patients who underwent ALIF as a salvage procedure after failed PLIF/TLIF between April 2014 to December 2019. We recorded all peri-operative data. In all patients the index level was exposed with a minimally invasive anterior retroperitoneal approach. Results. Thirty-two patients (average age: 46.4 years, median age 46.5, ranging from 21 to 74 years hold- 16 male and 16 female) underwent salvage ALIF procedure after failed PLIF/TLIF were included in the study. A minimally invasive anterior retroperitoneal approach to the lumbar spine was performed in all patients. In 6 cases (18.7%) (2 infection and 4 pseudarthrosis after stand-alone IF) only anterior revision surgery was performed. A posterior approach was necessary in 26 cases (81.3%). In most of cases (26/32, 81%) the posterior instrumentation was overpowered by the anterior cage without a previous revision. Three (9%) intraoperative minor complications after anterior approach were recorded: 1 dural tear, 1 ALIF cage subsidence and 1 small peritoneal tear. None vascular injuries occurred. Most of patients (90.6%) experienced an improvement of their clinical condition and at the last follow-up no mechanical complication occurred. Conclusions. According to our results, we can suggest that a favourable clinical outcome can firstly depend from technical reasons an then from radiological results. The removal of the mobilized cage, the accurate endplate and disc space preparation and the cage implant eliminate the primary source of pain reducing significantly the axial pain, helping to realise an optimal bony surface for fusion and enhancing primary stability. The powerful disc distraction given by the anterior approach allows inserting large and lordotic cages improving the optimal segmental lordosis restoration

Introduction Circumferential fusion is becoming increasingly popular and has been advocated by many authors to improve the fusion rates and clinical outcomes of the degenerative lumbosacral spine. Anterior lumbar interbody fusion (ALIF) with posterolateral fusion does provide direct access to the disc via a separate incision/ approach but has inherent neurovascular risks. Posterior lumbar interbody fusion (PLIF) with posterolateral fusion mandates bilateral exposure with significant retraction of neural elements with higher incidence of postoperative radiculitis. PLIF also reduces surface area for fusion and disrupts the posterior tension band. TLIF allows for a circumferential fusion through a single posterior incision with only slight retraction of the thecal sac and nerve roots, with much less morbidity and costs as compared to traditional PLIF and ALIF techniques. To our knowledge, there are no studies that report radiographic and clinical results of using recombinant human bone morphogenic protein (rhBMP-2) and allograft in a TLIF setting. The purpose of this study was to assess clinical & radiographic outcomes of patients treated with one or two level instrumented transforaminal lumbar interbody fusions (TLIF) performed with allograft and rh-BMP2 for treatment of symptomatic spondylolisthesis or degenerative disc disease. Methods During a consecutive 13 month period, 77 patients underwent TLIF procedures utilizing rhBMP-2 by one spine surgeon for lumbosacral degenerative and deformity conditions with simultaneous posterolateral fusions with allograft. Pedicle screw instrumentation (Monarch, DePuy Spine) provided distraction and a carbon-fiber curvilinear cage (Leopard, Depuy Spine) packed with rhBMP-2 (Large II Kit, total graft volume 8ml onto 77.4 sq. cm collagen sponge; Infuse: Medtronic Sofamor Danek) was placed into the disk space after hemifacetectomy and discectomy. The patients were followed at two weeks and three, six, 12 and 24 months after surgery patients were followed with several functional parameters such as the visual analog scale (VAS), SF-36 and Oswestry Disability Index (ODI) questionnaires. Fusion was assessed by static and dynamic radiographs at 6, 12, and 24 months as well as CT scans at 24 months. Results 71 patients were available for follow-up (92%) evaluation (mean 16 months; range 6–24 months). At 24 months, 85 percent and 81 percent of patients had improvement over preoperative ODI and SF-36 measures respectively. At 24 months, 70% of patients had good to excellent outcomes by both ODI and SF-36. We achieved 94% fusion rate with only four pseudarthroses. There was one wound infection treated with hardware removal and intravenous antibiotics. One patient had excessive bone growth into the foramen, necessitating surgical decompression with subsequent excellent clinical outcome. Ten patients had paresthesias on the side of the TLIF, all of which resolved by three weeks. There were no permanent neurologic deficits. Discussion The use of rhBMP-2 inside the cage, in combination with posterolateral allograft, can provide a high fusion rate and good clinical outcomes in a TLIF setting. The morbidity associated with iliac crest bone graft is avoided, with fusion rates approaching that of a true anterior/posterior circumferential fusion. Complications were few, with no significant neurologic sequelae from the placement of a structural graft into the anterior column through a posterior approach. Overgrowth of bone into the neural foramen, likely related to the residue of rhBMP-2 at the TLIF entry site, can occur. Care must be taken to place the TLIF cage device and the contained rhBMP-2 into the anterior half of the disk space to minimize the risk of this complication

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. Methods. Two online cross-sectional surveys distributed via UK and Australian professional networks to clinicians involved in LBP care, collected data on clinical discipline, practice setting and preferred care of five patient cases (ranging in age, pain duration, BMI, imaging findings, neurological signs/symptoms). Clinicians were also asked about willingness to randomise each patient case. Results. Of 174 responses (73 UK, 101 Australia), 70 were orthopaedic surgeons, 34 neurosurgeons, 65 allied health professionals (AHPs), 5 others. Most worked in public health services only (92% UK, 45% Australia), or a mix of public/private (36% Australia). Most respondents chose BCC as their first-choice management option for all five cases (81–93% UK, 83–91% Australia). For LFS, UK surgeons preferred TLIF (36.4%), whereas Australian surgeons preferred ALIF (54%). Willingness to randomise cases ranged from 37–60% (UK mean 50.7%), and 47–55% (Australian mean 51.9%); orthopaedic and neuro-surgeons were more willing than AHPs. Conclusion. Whilst BCC was preferred for all five patient cases, just over half of survey respondents in both the UK and Australia were willing to randomise cases to either LFS or BCC, indicating clinical equipoise (collective uncertainty) needed for RCT recruitment. Conflicts of interest. None. Sources of funding. No specific funding obtained for the surveys. DB, SA, AG and NEF have funding from the National Institute for Health Research (NIHR) UK (FORENSIC-UK NIHR134859); NEF, DB and SA have funding from the Australian National Health and Medical Research Council (NHMRC FORENSIC-Australia GA268233). AG has funding from Orthopaedic Research UK (combined with British Association of Spine Surgeons and British Scoliosis Society) and Innovate UK. NEF is funded through an Australian National Health and Medical Research Council (NHMRC) Investigator Grant (ID: 2018182)

Purpose of the study: Revision surgery for scoliosis in adults is a technical challenge. Indications include flat back, non-union, and syndromes adjacent to the instrumentation The purpose of this work was to evaluate the pertinence of the transforaminal lumbar interbody fusion (TLIF) method for revision surgery for scoliosis in adults. Material and methods: In our spinal surgery unit, 23 patients underwent revision surgery for thoracolumbar and lumbar scoliosis. A unique posterior approach was used. The TLIF was performed systematically at the lumbosacral level, at the non-union when it was present, and at the level of the Smith-Petersen osteotomies, as well as the levels above and below a transpedicular osteotomy. Seventeen patients presented flat back, ten non-union, five degenerative disease distal to the instrumentation and one degeneration proximal to the instrumentation. Nine patients had several indications for surgical revision. Five transpedicular osteotomies were performed in five patients. Results: Mean follow-up was 30 months (range 18–48). On average 2.3 levels (range 1–4) were involved in the TLIF. The fusion was extended to the sacrum in 22 patients. The mean operative time was 5h50m (range 3–8 hours). Mean blood loss was 2100ml (400–4500). Postoperative lumbar lordosis (L1S1) was 53.5°, giving an improvement of 23° copared with the preoperative lordosis. Among the postoperative complications, there was one neurological complications which recovered partially at last follow-up one case of deep infection of the operative site which require partial removal of the implants and one case of recurrent non-union. There was no loss of correction in the frontal or sagittal planes with the exception of one patient who developed an infection. None of the patients in the series required complementary anterior surgery. Conclusion: For revision surgery of scoliosis in the adult, a circumferential arthrodeis is needed to maintain the fusion. The TLIF method has the advantage of allowing intersomatic fusion via the posterior approach alone without opening the spinal canal. We consider that the TLIF technique is an alternative to two-phase procedures for revision surgery for scoliosis in adults. This method has given a good percentage of fusion in our series with little loss of correction

Transforaminal lumbar interbody fusion (TLIF) using an implanted cage is the gold standard surgical treatment for disc diseases such as disc collapse and spinal cord compression, when more conservative medical therapy fails. Titanium (Ti) alloys are widely used implant materials due to their superior biocompatibility and corrosion resistance. A new Ti-6Al-4V TLIF cage concept featuring an I-beam cross-section was recently proposed, with the intent to allow bone graft to be introduced secondary to cage implantation. In designing this cage, we desire a clear pathway for bone graft to be injected into the implant, and perfused into the surrounding intervertebral space as much as possible. Therefore, we have employed shape optimization to maximize this pathway, subject to maintaining stresses below the thresholds for fatigue or yielding. The TLIF I-beam cage (Fig. 1(a)) with an irregular shape was parametrically designed considering a lumbar lordotic angle of 10°, and an insertion angle of 45° through the left or right Kambin's triangles with respect to the sagittal plane. The overall cage dimensions of 30 mm in length, 11 mm in width and 13 mm in height were chosen based on the dimensions of other commercially available cages. The lengths (la, lp) and widths (wa, wp) of the anterior and posterior beams determine the sizes of the cage's middle and posterior windows for bone graft injection and perfusion, so they were considered as the design variables for shape optimization. Five dynamic tests (extension/flexion bending, lateral bending, torsion, compression and shear compression, as shown in Fig. 2(b)) for assessing long term cage durability (10. 7. cycles), as described in ASTM F2077, were simulated in ANSYS 15.0. The multiaxial stress state in the cage was converted to an equivalent uniaxial stress state using the Manson-Mcknight approach, in order to test the cage based on uniaxial fatigue testing data of Ti-6Al-4V. A fatigue factor (K) and a critical stress (σcr) was introduced by slightly modifying Goodman's equation and von Mises yield criterion, such that a cage design within the safety design region on a Haigh diagram (Fig. 2) must satisfy K ≤ 1 and σcr ≤ SY = 875 MPa (Ti-6Al-4V yield strength) simultaneously. After shape optimization, a final design with la = 2.30 mm, lp = 4.33 mm, wa = 1.20 mm, wp = 2.50 mm, was converged upon, which maximized the sizes of the cage's windows, as well as satisfying the fatigue and yield strength requirements. In terms of the strength of the optimal cage design, the fatigue factor (K) under dynamic torsion approaches 1 and the critical stress (σcr) under dynamic lateral bending approaches the yield strength (SY = 875 MPa), indicating that these two loading scenarios are the most dangerous (Table 1). Future work should further validate whether or not the resulting cage design has reached the true global optimum in the feasible design space. Experimental validation of the candidate TLIF I-beam cage design will be a future focus. For any figures or tables, please contact authors directly (see Info & Metrics tab above).

Introduction. The placement of a large interbody implant allows for a larger surface area for fusion, vis a vis, via retroperitoneal direct anterior, antero-lateral and lateral approaches. At the same time, spinal navigation facilitates a minimally invasive fixation for inserting posterior pedicle screws. We report on the first procedures in the United Kingdom performed by a single-surgeon at a single- centre using navigated robot-assisted spine surgery without the need for guide-wires. Materials and Methods. Whilst positioned in the supine or lateral position, a routine supine anterior lumbar interbody fusion (ALIF), and/or antero-lateral ALIF (AL-ALIF) and/or lateral lateral interbody fusion (LLIF) is performed. The patient is then turned prone or kept in the single lateral position (SPL) for insertion of the posterior screws performed under robotic guidance. Intraoperative CT scan 3D images captured then are sent to the Robotic software platform for planning of the screw trajectories and finally use again at the end of the procedure to confirm screw accuracy. We identified 34 consecutive patients from October 2019 to January 2020 who underwent robotic assisted spine surgery. The demographic, intraoperative, and perioperative data of all these patients were reviewed and presented. Results. Of the 34 patients, 65 levels were treated in total using 204 screws. Of the 21 patients (60%) who underwent single-level fixation, 14 of them (67%) were treated at the L5/S1 level, 3 at L3/L4, 3 at L4/L5 and 1 at L2/L3 level. The remaining 13 patients (40%) underwent multi-level fixation, of which 4 were adult scoliosis. 15 underwent a supine ALIF approach, 1 underwent AL-ALIF, 8 patients underwent combined LLIF and AL-ALIF approach in a lateral decubitus, whilst 9 underwent pure LLIF approach (of which 3 patients were in the single position lateral) and one patient had previous TLIF surgery. The average estimated blood loss was 60 cc. The average planning time was 10 min and the average duration of surgery was 50 min. The average patient age was 54 years and 64% (22/34) were male. The average BMI was 28.1 kg/m. 2. There were no re-interventions due to complications or mal positioned screws. Conclusion. Minimally invasive spine surgery using robot-assisted navigation yields an improved level of accuracy, decreased radiation exposure, minimal muscle disruption, decreased blood loss, shorter operating theatre time, length of stay, and lower complication rates. Further follow-up of the patients treated will help compare the clinical outcomes with other techniques

The April 2014 Spine Roundup. 360 . looks at: medical treatment for ankylosing spondylitis; unilateral TLIF effective; peg fractures akin to neck of femur fractures; sleep apnoea and spinal surgery; scoliosis in osteogenesis imperfect; paediatric atlanto-occipital dislocation; back pain and obesity: chicken or egg?; BMP associated with lumbar plexus deficit; and just how common is back pain?

Study design. Prospective randomized study. Objective. Primary aim of this study was to compare clinical and radiological results of transforaminal lumbar interbody fusion (TLIF) with posterolateral (interlaminar) instrumented lumbar fusion (PLF) in adult low grade (Meyerding 1 & 2) spondylolisthesis patients. Background data. Theoretically, TLIF has better radiological result than PLF in spondylolisthesis in most of the studies. Method. 24 patients of low grade adult spondylolisthesis were randomly allocated to one of the two groups: group 1- PLF and group 2-TLIF. Study period was between August 2010 to March 2013. All patients were operated by a single surgeon (CN). Posterior decompression was performed in all patients. Average follow up period was 18.4 months. Quality of life was accessed with Visual analogue scale and Oswestry Low Back Pain Disability Index. Fusion was assessed radiologically by CT scan and X-ray. Result. Though fusion was significantly better in TLIF group, clinical outcome including relief of back pain and neurogenic claudication were better in PLF group. Rate of complication was also lower in PLF group. Conclusion. Considering the low complication rate and similar or better clinical results, posterolateral instrumented lumbar fusion is the better option in low grade adult spondylolisthesis

RhBMP2 was used in thirty-six consecutive patients requiring interbody fusion with fifty-five levels (thirteen patients twenty levels ALIF, twelve patients seventeen levels TLIF, eleven patients eighteen levels ACDF) using anterior cervical locking plates and lumbar posterior pedicle screw constructs. All patients showed radiographic fusion at six months. Early lucency, subsidence, and increased pain occurred between six weeks and three months in 70% of ALIFS, 53% of TLIFS and 33% of ACDF’s. The average subsidence was 27% in ALIFS, 24% in TLIFS, and 53% in ACDF. Pain improved by the sixth month. We recommend alternative structural support when using RhBMP2. To determine effectiveness of RhBMP2 in interbody fusion with machined allograft spacers (MTF Synthes Spine USA femoral ring, TLIF and fibular ring cervical spacers). A prospective study of thirty-six consecutive patients requiring interbody fusion with fifty-five levels (thirteen patients twenty levels ALIF, twelve patients seventeen levels TLIF, eleven patients eighteen levels ACDF). Machined allograft spacers and RhBmp2 were supplemented with anterior locking plates in the cervical spine while the lumbar segments were supplemented posterior pedicle screws constructs. Patients were followed at two weeks, six weeks, three months, six months, one year. Patients were examined, had xrays, completed Oswestry scores, pain diagrams, and VAS for pain preoperatively and at every follow up appointment. All the patients showed radiographic evidence of fusion at six months after surgery. Early lucency and subsidence of allografts was observed in 70% of ALIFS, 53% of TLIFS and 33% of ACDF’s. The average subsidence was 27% (range13–42%) in ALIFS, 24% in TLIFS (range 13–40%), and 53% in ACDF. Subsidence and reporting of increased pain occurred between the six- week and three month follow up after which patients improved. Although high rates of early fusion can be accomplished with allograft spacers and rhBMP2 significant subsidence occurs in greater than 50% of lumbar cases and 30% of cervical cases due to early turnover and loss of structural support of the allograft. We recommend alternative structural support when using RhBMP2

Introduction: Fusion is typically indicated for degenerative spinal disorders with concomitant instability or painful spondylosis. Numerous techniques are used, with considerable variation in their invasiveness, risks and costs, although few can boast superiority for a given indication, particularly in relation to patient-orientated outcomes. This cohort study compared outcomes after fusion with translaminar screws (TS) versus transforaminal lumbar interbody fusion plus pedicular fixation (TLIF) plus pedicular fixation (both with decompressive procedures). Methods: The study was nested within our SSE Spine Tango data acquisition system. The suitability (or otherwise) for inclusion of every Spine Unit patient was indicated at the pre-operative consultation. Inclusion criteria: mono/bisegmental degenerative disc disease, facet syndrome or degenerative spondylolisthesis; German language; no previous surgery (except discectomy). Each surgeon consistently used his pre-stated, preferred method (TS or TLIF) for all his patients fitting the inclusion criteria. Before and 12 and 24 months post-surgery, patients completed the multidimensional Core Outcome Measures Index (COMI; 0–10 scale); after 12-months, global outcome was rated on a Likert-scale and dichotomised into “good” and “poor” groups. Results: 121 patients took part; 57 in the TS group (1 surgeon) and 64 in the TLIF group (4 surgeons). Gender distribution was identical in the two groups (67% women); TS were significantly older than TLIF (67±10y and 56±15y respectively, p< 0.05). There were no significant group differences at baseline for any COMI domain scores (all p> 0.05). TS had a significantly lower operation duration (p=0.0001) and blood-loss (p=0.01) but a longer hospital stay (p=0.005) than TLIF. Complication rates prior to discharge were similar in each group (2–4%). 94% patients returned questionnaires at 12-months. The groups did not differ in: reduction in COMI score, 3.5±2.9 (TS) vs 4.1±2.6 (TLIF)(p=0.23); % good outcomes, 72% (TS) vs 77% (TLIF)(p=0.58); satisfaction with treatment, 82% (TS) vs 88% (TLIF) (p=0.36). Thus far, 75 patients have reached the 2-yr follow-up and the trend for no group differences remains: % good outcomes, 81% (TS) vs 79% (TLIF)(p=0.91); satisfaction with treatment, 83% (TS) vs 85% (TLIF) (p=0.88). Discussion: This cohort study showed similar subjective results up to 2 years later for two different surgical techniques done for identical indications, but with differing surgical time, invasiveness and implant costs. The data thus far suggest that, for these degenerative disorders, optimal but invasive three-point stabilization is not required to achieve satisfactory results. Although the study design is not the highest in the “hierarchy-of-evidence”, it includes every single eligible patient and allows each surgeon to use his regular surgical procedure; it hence represents a practicable, complementary approach to the randomised-controlled-trial, with higher external validity (relevance/generalisability)

Several surgical options have been utilised to treat patients with back dominant lumbar disc disease. The purpose of our study was to compare the outcomes in patients who underwent lumbar fusion with an expandable interbody device (B-TWIN) using different surgical techniques (PLIF, TLIF or posterolateral screws alone). Observational study, retrospective analysis of prospectively collected data. Patients underwent a single level lumbar fusion. Group A: PLIF with B-Twin cage; Group B: TLIF with B-Twin cage and unilateral pedicle screw fixation and Group C: bilateral posterolateral screw fixation alone. Functional outcomes were assessed using: SF-36, Oswestry Disability Index (ODI), Distress and Risk Assessment Method scores (DRAM) and the visual analogue pain scores (VAS). There were 32 patients, 24 female and 8 male. Average age was 45 (range 33-63). Average follow up was12 months (range 2-36). Level of spinal fusion was 2 L3/4, 11 L4/5 and 13 L5/S1. Mean hospital stay was 5.8 days. VAS improved in all 3 groups A 5.83 – 5; B 8 – 4.83; C 5.71 – 2.3. ODI improved in all 3 groups A 0.5 – 0.35; B 0.51 – 0.44, C 0.42 – 0.16. There was no statistical difference on comparison of the three groups. There were no operative complications. One patient broke her interdody device during a all in the first post-operative week requiring a subsequent procedure. Lumbar interbody fusions can safely be performed using an expandable interbody device. Good functional outcomes can be achieved in the majority of well selected patients

Purpose: To review the sagittal lumbar and clinical profile of the two surgical procedures: TLIF (transforaminal lumbar interbody fusion and ALIF (anterior lumbar interbody fusion). Materials and methods: We carried out a retrospective study of 46 patients who underwent circumferential fusion in 2000–2001. TLIF was used in the first group (21) and ALIF in the second (25). The posterior approach with pedicle instrumentation was used in all patients. Lateral radiographs of the lumbar spine in neutral position and bipedestation were used for evaluation before and after surgery and during follow-up. The results were compared statistically using the Wilcoxon matched pairs test. Results: Lumbar lordosis was achieved with both techniques: TLIF+PF(posterior fusion) −33° (preoperative), −46° (postoperative) and ALIF+ PF −49° (preoperative), −54° (postoperative). However the height of the disc improved significantly with the anterior approach: TLIF+ PF 0.62 (preoperative), 1.35 (postoperative) and ALIF+PF 1 (preoperative), 4.65 (postoperative). The duration of surgery, blood loss and hospital stay were greater with ALIF+PF than with TLIF+PF. Conclusions: TLIF+PF has clinical and economic advantages over ALIF+PF. Lumbar lordosis and the area of instrumented lordosis was achieved with both circumferential fusion procedures and the only radiographic difference was the restoration of the disc height with ALIF

The purpose of this study was to investigate the efficacy and fusion rates of a unilateral pedicle screw construct supplemented with a translaminar screw in transforaminal lumbar interbody fusion (TLIF). The construct was used with an aim of providing suitable spine stiffness with minimal implant load for spinal fusion. Nineteen consecutive patients who underwent single level TLIF were included in the study. All patients had posterior spinal instrumentation using a unilateral pedicle screw construct with a contralateral translaminar screw. Patients were assessed preoperatively and at two, six, twelve and twenty-four weeks following surgery and at the end of one and two years. At every visit Oswestry disability index score,Visual analogue scale for pain and a pain diagram were recorded. A radiographic exam was also conducted and CT scan was done if there was concern about fusion. The average follow up was twenty-four months. There were twelve males and seven females with an average age of forty-eight years. All patients went on to clinical and radiographic union. Sixteen of nineteen patients had significant clinical improvement on VAS for pain, Oswestry scores and pain medication. Three patients had recurrence of radicular pain on the side of the TLIF leading to reexploration. In all three patients solid fusion was observed but scar tissue was evident and symptoms resolved following redecompression of the foramen. The biomechanical competence of a construct is evidenced by successful fusion. With the advent of minimally invasive techniques to achieve spinal fusion the goal is to use minimal instrumentation without compromising on the final stiffness of the spine. The construct of unilateral pedicle screws supplemented with a trans-laminar screw led to fusion in all our cases. It requires lesser soft tissue dissection and the posterior implants are 56% cheaper

Purpose: Circumferential arthrodesis of the lumbar spine is necessary in certain selected situations (lumbar stenosis with instability and preserved disc height or spondylolisthesis). Posterior lumbar interbody fusion (PLIF) raises the risk of significant bleeding and fibrosis around the roots as well as neurological complications. Transforaminal lumbar interbody fusion (TLIF) can avoid excessive bleeding and root displacement. The cages are inserted via a unilateral approach. Material and methods: This prospective single-centre study included twenty patients (nine men and eleven women), mean age 49 years. Indications for lumbar surgery were degenerative spondylolisthesis in nine patients and discal lumbar pain with foraminal stenosis in five. The clinical status was assessed with the Oswestry score, SF-36 and a visual analogue scale (VAS). Radiological assessment was based on inter-body fusion, segmentary lordosis, and lumbopelvic parameters. TLIF was associated with a posterior approach for insertion of titanium pedicular screws (CDH, Medtronic Sofamor Danek). Temporary unilateral distraction opened the foramen. Unilateral arthrectomy enabled a lateral approach to the disc without involving the roots and avoiding any movement of the dural sac. The disc was resected and the body endplates were prepared before introducing two cages (pyramesh) filled with macroporous ceramic granules (BCP) mixed with autologous bone marrow. Installation to two contourned rods enabled segmentary compression to stabilise the cages in association with posterolateral fusion. Results: Mean operative time was three hours. Mean blood loss was 400 ml. The patients were verticalised on day three without a corset. Mean follow-up was six months with retrospective evaluation of the Oswestry score, SF-36, and VAS. Postoperative pain resolved rapidly. Two patients developed transient incomplete L5 deficit. Bony bridges around the cases and posterolaterally were identified on the six-month x-rays. Spine view confirmed the quality of the fusion and lumbopelvic parameters revealed restoration of segmentary lordosis. Conclusion: The unilateral approach for TLIF is a reliable technique which does not compromise the roots. It enables very reliable primary stability and recovery of local segmentary lordosis. We are developing a minimally invasive percutaneous technique for this procedure

Introduction: Bone morphogenetic protein (BMP) has become widely used in the interbody space as part of a lumbar fusion. Complications can occur but are not completely understood or well documented. Methods: A prospective review of consecutive lumbar interbody fusions performed by a single surgeon was undertaken over a 2-year period. Early complications (defined as occurring within the first six weeks) were noted. The interbody cages (titanium Syncage, Synthes cages for ALIFs and PEEK Capstone, Medtronic cages for TLIFs) were filled with Infuse BMP-collagen sponge. Until early 2007, the amount of Infuse used was not strictly measured but after that time, only enough to fill the cage was used, with the volume assessed according to the manufacturer’s guidelines. Patients were routinely assessed preoperatively and at the six-week postoperative review using a visual analogue scale and the Oswestry disability score. Plain x-ray and MRI were obtained preoperatively, and plain x-ray was obtained postoperatively. In addition, if early problems developed, MRI scan was obtained. The incidence of complications was compared to that seen in similar procedures but where BMP was not used. Results: 114 patients, including 78 transforaminal inter-body fusions (TLIFs) and 36 anterior lumbar interbody fusions (ALIFs) were available for review. Early complications were noted in 10 of 114 patients. Two (both with TLIF) were not directly linked with BMP use: in the first, the cage migrated posteriorly and in the second, a deep infection developed. The remaining eight were associated with an exaggerated inflammatory response likely related to BMP use. Severe back pain associated with marked vertebral body inflammation seen on MRI was noted in two ALIF patients. The response occurred within 2 weeks of surgery, and settled with conservative treatment. Severe back pain and recurrence of leg pain developed in six TLIF patients. Fluid cyst formation within the spinal canal was seen on MRI in 4 of these. The cyst extended from the region of the posterior aspect of the cage into the canal and toward the area of the excised facet joint, resulting in compression of the exiting nerve root. In one case, the surgical site was re-explored and the cyst removed. In two cases, the cyst was aspirated under CT guidance and injected with steroid. In the final case a course of oral Prednisone was administered. In the remaining two TLIF cases, there was a diffuse inflammatory response in the region of the posterior aspect of the cage and adjacent epidural space but without discrete cyst formation. In one, oral Prednisone was prescribed. The second was treated expectantly. The majority of these complications were noted in 2007, after the dose of BMP was titrated in line with the manufacturer’s guidelines. In contrast, no such complications were seen when a similar technique but without BMP was undertaken in 33 posterior and 41 anterior interbody fusions. Discussion: The incidence of an exaggerated inflammatory response with BMP in the lumbar spine may be under-recognised. The majority of complications published to date relate to vertebral osteolysis and bony overgrowth, although a number of adverse responses to BMP reported to the FDA relate to fluid cyst formation or inflammation. With the rapid increase in BMP use, it is important that surgeons are aware of potential complications, and possible strategies to prevent and address them

Objective. To compare between the CAMISS-TLIF group and the OP-TLIF group in the clinical efficacy and radiographic manifest. Methods. This study was a registration study, selected 27 patients with lumbar spondylolisthesis from May 2011 to March 2014 in our hospital. Patients in one group are treated with computer assisted navigation minimally invasive TLIF (CAMISS -TLIF) while the others are treated with the OP-TLIF (OPEN-TLIF). The former group has 13 cases while the latter group has 14 cases. We collected information and present statistical analysis on the following aspects in order to compare the two different surgical methods of treatment. They are the operation duration, blood loss, days of hospitalisation, the preoperative and follow-up JOA and JOA improvement rate, the preoperative and follow-up ODI scores, the preoperative and follow-up VAS and Odom's criteria. By analysing the follow-up CT results, we compare the pedicle screw accuracy rate between the two groups in order to make a comprehensive assessment of these two surgical methods. Results. There is a significant difference in blood loss, follow-up JOA improvement rate and follow-up ODI scores between the CAMISS-TLIF group and OP-TLIF group (P <0.05), while in other fields there is no statistically significant differences. Conclusion. CAMISS-TLIF surgical approach has an advantage of less blood loss, less muscle stripping, smaller surgical trauma and more quickly recovery after surgery

Anterior Lumbar Interbody Cages are used to recreate the lumbar lordosis in scoliosis surgery as anterior instrumentation is usually kyphogenic. We report two cases in which an anterior release was performed and interbody cages were used.In both these patients the cage was displaced anteriorly by an incorrectly positioned pedicle screw during posterior instrumentaion. In one case the cage was retrieved and correctly repositioned from the back using a TLIF approach, in the other this was noticed only post-operatively and patient needed another anterior surgery. We recommend a lateral Image Intensifier screening for combined anterior and posterior cases in which anterior cages are used in addition to posterior pedicle screws to prevent this complication