Abstract. Objectives. There is still controversy in the literature over whether Cervical Foraminotomy or Anterior Cervical discectomy and fusion (ACDF) is best for treating cervical Radiculopathy. Numerous studies have focused on the respective complication rates of these procedures and outcome measures with a lack of due consideration to preoperative MRI findings. Proximal foraminal stenosis can theoretically be accessed via either approach. We aimed to investigate whether patient reported outcome measures (PROMs) favoured one approach over the other in patients with proximal foraminal stenosis. Methods. A single centre retrospective review of patients undergoing either ACDF or Cervical foraminotomy over the period 2012 to 2022. VAS, Neck disability index (NDI), EQ5DL and Patient Satisfaction on a Five Point Likert scale were obtained. Patients who had both an ACDF and a Foraminotomy were excluded. Axial MRI images were analysed and the location of the worst clinically relevant disc herniation stratified as follows: Central (1), Paracentral (2) and Foraminal (3). Correlations and average PROMs were analysed in SPSS. Results. PROMs scores were available for 33 ACDF patients and 37 Foraminotomy patients. Average surgery time in ACDF group was 167 minutes while Foraminotomy 142 minutes. Average Length of hospital stay was 6.24 days in the Foraminotomy group and 3.54 days in the ACDF group. 18 patients were excluded due to having both surgeries (2 of which developed CSF leaks postoperatively). Of the included patients there were no postoperative complications. 13 patients in the ACDF had Central or Paracentral stenosis in addition to proximal Foraminal stenosis, 3 patients in the Foraminotomy group had some significant Paracentral herniation just before the Proximal foramen. The majority of patients in both groups had pure proximal Foraminal stenosis (N= 17 (ACDF), 20 (Foraminotomy). The results showed no significant difference in PROMs between patients who received an ACDF or a Foraminotomy for Proximal foraminal stenosis (EQ5DL, NDI, and satisfaction, P= 0.268, 0.253 and 0.327). There was no correlation between location of the stenosis and PROM scores in either group. Conclusions. Our data suggest that Proximal foraminal stenosis can be effectively addressed by either an anterior ACDF or a Foraminotomy with no difference in complication rates. Foraminotomy has the benefit of no implant cost but longer hospital stay. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Objective:. To observe the incidence of intra-operative vascular injuries during anterior cervical decompression and fusion (ACDF). Secondly, management and monitoring of the outcome post vascular injury during ACDF. Methods:. This a prospective study. A review of all spinal patients' records was performed from June 2006 to April 2011. A comprehensive literature review was also utilized. Inclusion criteria – all patients had ACDF post trauma. All non-traumatic cases were excluded. Results:. The study consisted of 55 patients; 15 were females and 40 were males. The age distribution was 23–65 years. Two patients were excluded due to non-traumatic causes. Of the remaining 53 patients, four sustained intra-operative vascular injuries during ACDF surgery. All 4 patients had corpectomies, and one case was an iatrogenic injury. The commonly injured vessel during the ACDF surgery was the left vertebral artery. Haemostatic control was achieved via tamponade and haemostatic agents. The left common carotid was iatrogenically injured in one case and was treated by microvascular repair. Three patients were treated with antiplatelet therapy for three months duration. The patient with an iatrogenic injury was treated with anticoagulation therapy for three months duration. All computerized tomographic angiograms at three months follow up illustrated patent vessels. Conclusion:. There is an increased incidence of intra operative vascular injuries during ACDF associated with corpectomies. It is essential to be aware of the low incidence of intra operative arterial injury during ACDF and to have a management approach, such as tamponade or microvascular repair. Anticoagulation and antiplatelet therapy is effective in decreasing the complications of vascular injuries post ACDF

Background: Cervical myelopathy and radiculopathy has been treated commonly with anterior cervical decompression and fusion with autologous bone graft and anterior cervical plating. Long term results have shown excellent pain relief and 73%–90% fusion rates. However, the development of late adjacent-level disease has been reported following anterior cervical arthrodesis which recently have been correlated to clinical findings. The Bryan disc arthroplasty device was developed to preserve the kinematics of the functional spine unit thus preventing adjacent level disease. There have been few studies comparing the incidence of adjacent level changes in patients undergoing ACDF compared to implantation of a Bryan disc arthroplasty device. Objectives: The object of this study is to compare the clinical results and radiographic outcomes of anterior cervical decompression and fusion versus cervical disc replacement using the Bryan Cervical Disc Prosthesis (Medtronic Sofamor Danek, Memphis, TN) in terms of overall range of motion (ROM) of the cervical spine; ROM, anterior intervertebral height (AIH), posterior intervertebral height (PIH) and radiographic changes at the implanted and adjacent levels. Methods: The study consisted of 105 patients with symptomatic single or two-level cervical disc disease. Fifty-one received the Bryan Cervical Artificial Disc Prosthesis (Medtronic Sofamor Danek, Memphis, TN). A total of 63 Bryan disc were placed in these 51 patients. A single-level procedure was performed in 39 patients and a two-level procedure in the other twelve. The patient group who underwent ACDF totaled 54 patients which consisted of 26 single level cases and 28 double level cases. The Bryan group had a mean follow-up 19 months (12–38). The mean follow-up for the ACDF group was 20 months (12–40 months). All patients were evaluated using static and dynamic cervical spine radiographs as well as MR imaging. All patients underwent anterior cervical discectomy followed by anterior cervical plating or implantation of the Bryan artificial disc prosthesis, done by one surgeon. Clinical evaluation included the visual analogue scale (VAS), and neck disability index (NDI). Radiographic evaluation included static and dynamic flexion-extension radiographs in an upright position using the computer software (Infinitt PiviewSTAR 5051) program. Range of motion/disc space angle and inter vertebral height were measured at the operative site and adjacent levels. Functional spinal unit (FSU) and overall sagittal alignment (C2–C7) were also measured pre-operatively, postoperatively and at final follow-up. ROM was calculated for all 3 areas and data collected were compared from pre operative to last follow-up as well as between the two groups. Radiographic assessment for adjacent level changes was also done. Radiologic change was analyzed using chi square test (95% confidence interval). Other data were analyzed using the mixed model. (SAS enterprise guide 4.1 version). Results: There was clinical improvement within each group in terms of VAS and NDI scores from pre-op to final follow-up for both single (VAS: p=0.8371, NDI: p=0.2872) and double (VAS: p=0.2938, NDI: p=0.6753) level surgeries but not significantly between the two groups. Overall, ROM and intervertebral height was relatively well maintained during the follow-up in the Bryan group compared to ACDF. Comparing the pattern of ROM measurements from pre-op to final follow-up between the two arms regardless of the number of levels operated on; significant differences were noted for overall ROM of the cervical spine (p< .0001) and all other levels except at the upper level for single level surgeries (p=0.2872). In terms of inter vertebral height measurements from pre-op to final follow-up, statistically significant (p< 0.0001 and p=0.0172) differences in the pattern between the two groups were noted at all levels except for the AIH of single level surgeries at the upper (p=0.1264) and lower (p=0.7598) levels as well as PIH for double level surgeries at the upper (p=0.8363) level. Radiologic change was 3.5 times more observed for the ACDF group compared to the Bryan group. Conclusion: Clinical status of both groups, regardless of the number of levels, showed improvement. Although clinical outcomes between the two groups were not significantly different at final follow-up, radiographic parameters, namely ROM and intervertebral heights at the operated site, some adjacent levels as well as FSU and overall sagittal alignment of the cervical spine were relatively well maintained in our Bryan group compared to our ACDF group. We surmise that to a certain degree, the maintenance of these parameters could contribute to reduce development of adjacent level change. Noteworthy is that radiographic change was 3.5 times more observed for ACDF surgeries. A longer period of evaluation is needed, to see if all these radiographic changes will translate to symptomatic adjacent level disease

Introduction: Autologous bone graft is currently considered the gold standard for anterior cervical discectomy and fusion (ACDF). However, the harvesting of bone graft from the ilac crest is frequently associated with significant patient morbidity. We report on the safety and efficacy of trabecular metal blocks for achieving a stable interbody fusion for ACDF when compared to iliac crest bone graft for a small group of patients. Methods: This is a prospective trial of patients who underwent consecutive ACDFs between September 2004 and September 2007. Patients received one of two materials for their fusion, either trabecular metal blocks or autologous iliac crest bone graft. Each operation was performed by the same spinal surgeon (LT), and all patients had fixation with an anterior titanium plate to enhance interbody arthrodesis. Clinical outcome was assessed with a neck disability score (Vernon and Mior 1991) that was mailed to all participants; bone graft patients were also asked to complete a bone graft morbidity questionnaire (Silber et al. 2003). Radiological followup was assessed with computed tomography and flexion-extension radiographs. A minimum followup time of 3 months was required for inclusion into the study, and unpaired t-tests were used to evaluate statistical differences between relevant sets of data. Results: A total of 31 patients were included into the study, with 15 in the trabecular metal group (TM) and 16 in the iliac crest bone graft group (ICBG). The TM group included 10 males (67%) with a median age of 42 years (range 18–72). Median neck disability score was 18% (2–38) and stable bony ingrowth was observed in all patients (100%) on postoperative scans. Median followup time was 8 months (3–16) for TM patients and 20.3 months (7–36 months) for the ICBG group. In comparison, the ICBG group included 8 males (50%) with a median age of 53.3 years (43–70). Median neck disability score was worse at 30% (4–50), with a significant difference of 12% observed after t-test analysis (p value < 0.02). In addition, there was significant morbidity associated with the harvesting of autologous bone graft, with more than 50% of patients experiencing acute and/or chronic symptoms. Two radiological pseudoarthroses (8%) were observed postoperatively, of which one was manifested clinically. Discussion: These results confirm that, for our population group, trabecular metal implants are both safe and effective for use in ACDF when compared to the gold standard of autologous bone graft. Furthermore, trabecular metal implants avoid the morbidity associated with the harvesting of iliac crest bone graft. We believe the results so far are encouraging for our small group of patients but a larger, randomised control trial is needed to provide definitive results

Purpose of study: To demonstrate the safety and efficacy 3 and 4-level ACDF with stand-alone (no additional anterior fixation) intervertebral cages. Methods and results: A consecutive cohort of 19 patients undergoing 3 (n=15) and 4-level (n=4) ACDF with Solis cages over 4 years was studied (mean follow-up 24 months). Outcome measures were clinical (VAS scores for neck and arm pain, myelopathy scores) and radiological (disc height, kyphotic angles, fusion). Neck pain scores improved from 5.1 pre-operatively (range 0–10, s.d. 4) to 2.8 post-operatively (range 0–10, s.d.5), t=3.7, P< 0.0002. Arm pain scores improved from 5.3 pre-operatively (range 0–10, s.d. 5) to 2.5 post-operatively (range 0–8, s.d. 3), t=2.8, P< 0.009. Pre-operative myelopathy scores averaged 10.6 (range 7–16, s.d. 4.7) rising to 12.8 post-operatively (range 10–17, s.d. 3.9). Although there was no statistically significant change in myelopathy scores, no patient experienced a worsening of their myelopathy score after surgery. There were no operative complications. Radiological follow-up demonstrated early improvement in disc space heights (pre-op 3.1 mm, range 1–6 mm; post-op 5.6 mm, range 4–9 mm) but, at 12 months, two patients demonstrated asymptomatic evidence of cage settling and loss of disc height. There was no incidence of pseudarthrosis. No patient has thus far required further surgery. Conclusion: Multi-level cervical disc disease can be managed safely and effectively by 3 or 4-level discectomy and fusion with stand-alone intervertebral cages. Ethics approval: None – audit. Interest Statement: None

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.

The aim of most new implants for cervical disc replacement is to maintain or restore function. The Dynamic Cervical Implant (DCI(tm), Paradigm Spine) aims at combining the advantages of the gold standard fusion technique with the motion preservation philosophy. DCI has a limited motion: it works like a shock absorbing spring and may help to slow down adjacent segment degeneration.

Between 2007 and 2009 we selected 79 patients aged 32 to 73 years for treatment with DCI at either one or two levels (10 patients). Indications were radiculopathies (n=45), axial pain (n=4) or spondylotic spinal stenosis (n=30) with out chronic myelopathy. Patients are followed up at 3, 6, and 12 months after surgery.

Disc surgery was performed at C3/C4 (n=2), C4/5 (n=6), at C5/6 (n=43), C6/7 (n=37) and at C7/T1 (n=1). In flexion/extension radiographs motion rapidly increased after surgery. However, 5 of 19 treated levels were fused (seen at 6 or 12 months). After implant footprint was changed and larger sizes were provided only 2 of 67 segments fused. Still 96% of the patients rated their clinical result as excellent or good. There were no implant related complications or revision surgery.

Disc replacement with DCI is a new strategy that is positioned in between anterior cervical fusion and disc prosthesis. Clinical results are as good as in anterior cervical fusion. Adjacent segment protection must be judged in future follow-ups. We were able to show that the change of implant footprint has significantly reduced fusion rate.

Introduction. To develop an international guideline (AOGO) about use of osteobiologics in Anterior Cervical Discectomy and Fusion (ACDF) for treating degenerative spine conditions. Method. The guideline development process was guided by AO Spine Knowledge Forum Degenerative (KF Degen) and followed the Guideline International Network McMaster Guideline Development Checklist. The process involved 73 participants with expertise in degenerative spine diseases and surgery from 22 countries. Fifteen systematic reviews were conducted addressing respective key topics and evidence were collected. The methodologist compiled the evidence into GRADE Evidence-to-Decision frameworks. Guideline panel members judged the outcomes and other criteria and made the final recommendations through consensus. Result. Five conditional recommendations were created. A conditional recommendation is about the use of allograft, autograft or a cage with an osteobiologic in primary ACDF surgery. Other conditional recommendations are about use of osteobiologic for single or multi-level ACDF, and for hybrid construct surgery. It is suggested that surgeons use other osteobiologics rather than human bone morphogenetic protein-2 in common clinical situations. Surgeons are recommended to choose one graft over another or one osteobiologic over another primarily based on clinical situation, and the costs and availability of the materials. Conclusion. This AOGO guideline is the first to provide recommendations for the use of osteobiologics in ACDF. Despite the comprehensive searches for evidence, there were few studies completed with small sample sizes and primarily as case series with inherent risks of bias. Therefore high quality clinical evidence is demanded to improve the guideline

Introduction. Aim was to compare the functional outcome of anterior cervical decompression and fusion (ACDF) with stand-alone tricotical iliac crest auto graft verses stand-alone PEEK cage. Material and methods. Prospectively collected data of 60 patients in each group was compared. Results. There was statistically significant improvement noted in postoperative Modified Japanese Orthopaedic Association scores at one year follow up for both the groups. Perioperative complications were significantly higher in the autograft group when compared with the PEEK cage group. Among the 94 patients who underwent single level non-instrumented ACDF only 4 (4.25%) had psuedoarthrosis. The fusion rate for single level ACDF in our series was 95.74%. Among the 25 patients operated for two level non-instrumented ACDF, 6 patients (24.00%) had pseudoarthrosis. The fusion rate for two levels ACDF in our series is 76.00%. There was no significant difference in fusion rates of the PEEK cage when compared to auto graft group. Conclusion. Fusion rates in ACDF are independent of interbody graft material. Fusion rates for single level ACDF is significantly higher than two levels ACDF. ACDF with PEEK is the fusion technique of choice with fewer complications and better functional recovery

Introduction. Aim was to compare the functional outcome of anterior cervical decompression and fusion (ACDF) with stand-alone tricotical iliac crest auto graft verses stand-alone PEEK cage. Material and methods. Prospectively collected data of 60 patients in each group was compared. Results. There was statistically significant improvement noted in postoperative Modified Japanese Orthopaedic Association scores at one year follow up for both the groups. Perioperative complications were significantly higher in the autograft group when compared with the PEEK cage group. Among the 94 patients who underwent single level non-instrumented ACDF only 4 (4.25%) had psuedoarthrosis. The fusion rate for single level ACDF in our series was 95.74%. Among the 25 patients operated for two level non-instrumented ACDF, 6 patients (24.00%) had pseudoarthrosis. The fusion rate for two levels ACDF in our series is 76.00%. There was no significant difference in fusion rates of the PEEK cage when compared to auto graft group. Conclusion. Fusion rates in ACDF are independent of interbody graft material. Fusion rates for single level ACDF is significantly higher than two levels ACDF. ACDF with PEEK is the fusion technique of choice with fewer complications and better functional recovery

Anterior cervical discectomy and fusion (ACDF) is a well-established spinal operation for cervical disc degeneration disease with neurological compromise. The procedure involves an anterior approach to the cervical spine with discectomy to relieve the pressure on the impinged spinal cord to slow disease progression. The prosthetic cage replaces the disc and can be inserted stand-alone or with an anterior plate that provides additional stability. The literature demonstrates that the cage-alone (CA) is given preference over the cage-plate (CP) technique due to better clinical outcomes, reduced operation time and resultant morbidity. This retrospective case-controlled study compared CA versus CP fixation used in single and multilevel anterior cervical discectomy and fusion for myelopathy in a tertiary centre in Wales. A retrospective clinico-radiological analysis was undertaken, following ACDF procedures over seven years in a single tertiary centre. Inclusion criteria were patients over 18 years of age with cervical myelopathy who had at least six-month follow-up data. SPSS was used to identify any statistically significant difference between both groups. The data were analysed to evaluate the consistency of our findings in comparison to published literature. Eighty-six patients formed the study cohort; 28 [33%] underwent ACDF with CA and 58 [67%] with CP. The patient demographics were similar in both groups, and fusion was observed in all individuals. There was no statistical difference between the two constructs when assessing subsidence, clinical complication (dysphagia, dysphonia, infection), radiological parameters and reoperations. However, a more significant percentage [43% v 61%] of patients improved their cervical lordosis angle with CP treatment. Furthermore, the study yielded that surgery to upper cervical levels results in a higher incidence of dysphagia [65% v 35%]. Finally, bony growth across the cage was observed on X-ray in 12[43%] patients, a unique finding not mentioned in the literature previously. Our study demonstrates no overall difference between the two groups, and we recommend careful consideration of individual patient factors when deciding what construct to choose

Background. The controversy concerning the benefits of unisegmental cervical disc arthroplasty (CDA) over anterior cervical discectomy and fusion (ACDF) is still open because some randomised clinical trial (RTC) comparing ACDF with CDA have been highly inconclusive. Most of these studies mixed disc prosthesis with dissimilar kinematic characteristics. To date, a compilation of the clinical and radiologic outcomes and adverse events of anterior cervical discectomy and fusion (ACDF) compared with a single cervical disc arthroplasty (CDA) design, the Bryan disc has partially accomplished. Methods. This is a systematic review of RCTs with level I-II evidence. Only RCTs reporting clinical outcomes were included in this review. After a search on different databases including PubMed, Cochrane Central Register of Controlled Trials, and Ovid MEDLINE, a total of 10 RCTs out of total 51 studies were entered in the study. RTC's were searched from the earliest available records in 2005 to December 2014. Results. Five studies were Level I, and five were Level II. Out of a total of 1101 patients, 562 patients were randomly assigned into the Bryan arthroplasty group and the remaining 539 patients into the ACDF group. The mean follow-up was 30.9 months. Patients undergoing CDA had lower Neck Disability Index, and better SF-36 Physical component scores than ACDF patients. Patients with Bryan CDA had also less radiological degenerative changes at the upper adjacent level. Overall adverse events were twice more frequent in patients with ACDF. The rate of revision surgery including both adjacent and index level were slightly higher in patients with ACDF, showing no statistically significant difference. Conclusions. This review of evidence level I-II RCTs comparing clinical and radiological outcomes of patient undergoing Bryan arthroplasty or ACDF indicated a global superiority of the Bryan disc. The impact of both surgical techniques on the cervical spine (radiological spine deterioration and/or complications) was more severe in patients undergoing ACDF. However, the rate of revision surgeries at any cervical level was equivalent for ACDF and Bryan arthroplasty. These data suggest that even though the loss of motion has a determinant influence in the development of degenerative changes in ACDF cases, these kinematic factors do not imply a higher rate of symptomatic adjacent segment degeneration requiring surgery. Level of Evidence. Level I

Background: Smaller versions of threaded lumbar cages were developed for cervical spine to obviate the need for allograft, iliac autograft use and to provide initial stability before fusion. Clinical trials of threaded cervical fusion cages have shown higher fusion rates and lower rates of graft-donor site complications. Study design/Aims: Prospective. Radiological and clinical outcomes of an age, sex and diagnosis matched patient population who underwent cervical fusion with (A) BAK/C cages filled with autograft reamings (Center-pulse Spine-tech Inc., Minneapolis, MN) (N=50) were compared with (B) Anterior cervical decompression and fusion (ACDF, N=50). Methods: Patients with symptomatic cervical discogenic radiculopathy were treated with either anterior cervical discectomy with uninstrumented bone-only fusion (ACDF) or BAK/C fusion cage(s). Independent radiographic assessment of fusion was made and patient-based outcome was assessed by a Short Form (SF)-36 Health Status Questionnaire. All patients had minimum follow up of at least 2 years. Results: Similar outcomes were noted for duration of surgery, hospital stay, improvements in neck pain and radicular pain in the affected limb, improvements in the SF-36 Physical Component subscale and Mental Component subscale, and the patients’ perception of overall surgical outcome. Symptom improvements were maintained at 2 years. Iliac crest harvesting was carried out as a standard procedure in all cases of ACDF whereas only 2 cases in BAK/C group required the same. Average operative time of 115 minutes and 145 minutes, blood loss of 110ml and 175ml and hospital stay of 1.5 and 3.5 days were noted for BAK/C and ACDF groups respectively. Successful fusion was achieved in 49 cases in BAK/C and 46 patients in ACDF group. None of the patients in the BAK/C group had reappearance of symptoms while 3 patients in ACDF group had developed symptomatic adjacent level disc disease. The complication rate for the ACDF group was 9% compared with an overall complication rate of 3% with BAK/C. Complications that necessitated a second operative procedure included. Graft dislodgement (N=3) and. Cage subsidence, both requiring re-operation in the form of ACDF with plate supplementation. Conclusions: These results demonstrate that outcomes after a cervical fusion procedure with a threaded cage are the same as those of a conventional uninstrumented bone-only anterior discectomy and fusion with a low risk of complications, less operative time and rare need for autogenous bone graft harvest

Introduction. Anterior cervical decompression and fusion (ACDF) is considered a standard surgical treatment to degenerative discogenic diseases. Lately, the question arises whether or not ACDF significantly influences the progression of adjacent disc degeneration (ADD). The etiology of ADD is obscure and it has not been fully understood whether ADD is a consequence of fusion or it represents the aging pathway of the degenerative cervical process, thus making it a controversial topic [1-3]. There have been several discussions about the possibility of ACDF altering biomechanical conditions at adjacent segments, therefore resulting in increased load and excessive motion [3,4]. The purpose of this study was to compare the cervical segmental motion pre- and post-ACDF using novel 3D analytical techniques. Methods. Nine patients (2F/7M, mean age: 54.1 years, range 36–76 y.o.) underwent ACDF due to symptomatic cervical degenerative discogenic disease. One-level ACDF was performed in 4 patients, whereas 2-level ACDF was done in five, using cylindrical titanium porous cage implants. Pre- and post (postoperative periods ranged from 11-months, 25 days to 12-months, 22 days, mean postoperative period: 12.09 months) surgery, dynamic-CT examinations were conducted in neutral, flexion and extension positions. Subject-based 3D CT models were created for segmental motion analysis (Fig. 1). Six-degrees-of-freedom 3D segmental movements were analyzed using a validated Volume-Merge methods (accuracy: 0.1 mm in translation, 0.2°in rotation) [5]. The segmental translation was evaluated by the segmental translations of gravity centers of endplates (Fig. 2). Disc-height distribution was measured using a custom-written Visual C++ routine implementing a lease-distance calculation algorithm. The mean translation distance was calculated for the each adjacent level (Fig. 2). Differences of segmental motions and mean disc height between pre- and post-surgery at each level were compared by the Wilcoxon signed rank test. Results were presented mean±SEM. Results. Regarding the fusion level, the data shows decreases in both the flexion/extension (F/E) angular range of motion (ROM) (7.46±1.17°preoperatively vs. 3.14±0.56°post-operatively, p<0.003) and the segmental translation in the anterior/posterior direction (AP translation) after surgery (1.22±0.20 mm pre-operatively and 0.32±0.11 mm post-operatively, p<0.01). For the adjacent levels category (inferior and superior combined), the E/F angular ROM was larger after surgery (6.74±1.22°pre-operatively vs. 8.48±0.56°post-operatively, p<0.03). The lateral and axial rotational angular ranges of motion pre- and post-surgery did not show any statistically differences at the adjacent levels. The AP translation at the adjacent levels did not change after surgery (1.22±0.26 mm pre-operatively and 1.45±0.29 mm post-operatively). Translations in lateral and cranio-caudal directions also did not show change following surgery. The mean disc height in the adjacent level (2.39±0.14 mm) showed no differences with respect to the post-surgical measurements (2.40±0.19 mm). Conclusions. The use of a high-accuracy in vivo 3D kinematic analysis method enabled the detection of subtle changes in segmental movement between pre- and post-ACDF conditions. The result of the current study showed increased segmental movements in F/E angles at the adjacent level. These results are consistent with the some previous studies in the literature [4,6-11]. The magnitude of the increased movement, however, was only 1.74°from full-full-flexion to full-extension and no increase was found in AP translation. No disc height loss associated with disc degeneration was observed during a 1-year period after ACDF. Longer follow-up studies with larger patient cohorts will be required to investigate whether the increased F/E angle at the adjacent level effectively causes symptomatic ADD

We have examined how many and which potential complications (PCs) are recorded on the consent form by a group of consultant surgeons performing common spinal procedures - anterior cervical discectomy and fusion (ACDF) and posterior lumbar discectomy and/or medial facetectomy (PLD). Email survey. Consultant spinal surgeons performing ACDF and/or PLD practicing in Southwest England. Identification of the PCs each surgeon listed on the consent form for the specified procedures. There were 23 responses from 28 Consultant surgeons approached. 21 surgeons performed both ACDF and PLD, 2 performed only PLD. Surgeons quoted 5 to 17 (mode 10) PCs for ACDF and 4 to 15 (mode 13) for PLD. These did not necessarily represent the most common or most dangerous PCs recorded in the literature. 1,2. Small difference in PCs mentioned by Neurosurgeons and Orthopaedic surgeons was seen (ACDF mode: 12vs10, PLD mode: 12vs13). There was a strong correlation between the number of PCs recorded by surgeons for ACDF and PLD. We have found a wide variation in consenting practice amongst a group of surgeons performing common spinal operations. Issues of consent are common causes of formal complaints and potential litigation, causing anxiety for both patient and surgeon. A more homogenous consent process, employing objective measures where possible, may help reduce this burden and may be achieved by setting a national standard

Introduction: Anterior cervical discectomy and inter-body fusion (ACDF) is recognised as an effective surgical treatment for cervical degenerative disc disease. The goals of anterior discectomy, interbody graft placement, and subsequent fusion, are to improve and maintain intervertebral height, establish and maintain physiological cervical lordosis, and achieve arthrodesis so as to eliminate pathological motion. Establishing the most clinically effective and cost effective operative approach to achieve these goals while, at the same time, minimising post-operative complications, is currently an evolving process. One view is that the use of anterior cervical plates reduces graft-related complications, maintains the cervical alignment, and leads to a higher incidence of fusion. In addition, there is evidence to suggest that there is a direct cost benefit of earlier return to pre-operative function and employment. Bone graft: Iliac crest autograft would be regarded as the gold standard source of bone for ACDF. However, donor site complications (due to harvesting autograft) are not insignificant and range from 1% to a sizeable 29%. These complications include iliac crest fracture, infection, persisting pain, neural injury, bowel injury, etc. With the advent of bone banks, allograft has become available and eliminates the problem of graft-harvest related complications. There is a theoretical risk of disease transmission and a corresponding difficulty with patients accepting donated tissue. To date, no HIV cases transmission has occurred from ACDF allograft. There are several studies that demonstrate a significant difference in fusion rates when comparing allograft and autograft. The preponderance of data from the literature supports the conclusion that the use of allograft in ACDF can lead to a higher incidence of graft collapse, pseudarthrosis, and possible subsequent revision surgery. Bishop et al., (Spine 1991 16:726–9): have documented a higher increase in pseudarthrosis rate, graft collapse, and interspace angulation in the allograft group compared to the autograft group. Therefore, the dilemma of allograft being preferred as a basis of eliminating graft harvesting complications, while at the same time being associated with a higher incidence of fusion failure and deformity, have led some surgeons to trial the combination of allograft with anterior plate fixation. Shapiro (J Neurosurg 1966 84:161–5) has reported no incidences of fusion failure, graft collapse, progressive kyphosis, or plate-related complications in 82 consecutive single and multiple level ACDF’s using allograft and anterior plating. Treatment failure: The incidence of the following complications have been reported in the literature. (Graham JJ. Spine 1989 14:1046–50). Pseudarthrosis – 3%–36%. Graft collapse – 3%–14%. Graft extrusion – 0.5%–4%. These figures are regardless of the graft source and are significant. Recent studies show that the combination of graft and anterior plate fixation virtually eliminates the complication of graft extrusion, and also decreases the risk of graft collapse and development of pseudarthrosis. There are also studies that contend that plate fixation can maintain proper lordotic alignment of the spine more effectively than can ACDF without plating. I contend that the use of contemporary cervical plates significantly decreases the rate of fusion failure and graft-related complications without imparting significant implant-related complications. As a result, there is decreased overall risk to the patient. The current type of plates which are available are unicortical with locking systems that substantially decrease the risk of screw loosening or hardware migration

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

Objectives. Pulsed electromagnetic field (PEMF) stimulation was evaluated after anterior cervical discectomy and fusion (ACDF) procedures in a randomized, controlled clinical study performed for United States Food and Drug Administration (FDA) approval. PEMF significantly increased fusion rates at six months, but 12-month fusion outcomes for subjects at elevated risk for pseudoarthrosis were not thoroughly reported. The objective of the current study was to evaluate the effect of PEMF treatment on subjects at increased risk for pseudoarthrosis after ACDF procedures. Methods. Two evaluations were performed that compared fusion rates between PEMF stimulation and a historical control (160 subjects) from the FDA investigational device exemption (IDE) study: a post hoc (PH) analysis of high-risk subjects from the FDA study (PH PEMF); and a multicentre, open-label (OL) study consisting of 274 subjects treated with PEMF (OL PEMF). Fisher’s exact test and multivariate logistic regression was used to compare fusion rates between PEMF-treated subjects and historical controls. Results. In separate comparisons of PH PEMF and OL PEMF groups to the historical control group, PEMF treatment significantly (p < 0.05, Fisher’s exact test) increased the fusion rate at six and 12 months for certain high-risk subjects who had at least one clinical risk factor of being elderly, a nicotine user, osteoporotic, or diabetic; and for those with at least one clinical risk factor and who received at least a two- or three-level arthrodesis. Conclusion. Adjunctive PEMF treatment can be recommended for patients who are at high risk for pseudoarthrosis. Cite this article: D. Coric, D. E. Bullard, V. V. Patel, J. T. Ryaby, B. L. Atkinson, D. He, R. D. Guyer. Pulsed electromagnetic field stimulation may improve fusion rates in cervical arthrodesis in high-risk populations. Bone Joint Res 2018;7:124–130. DOI: 10.1302/2046-3758.72.BJR-2017-0221.R1

The August 2015 Spine Roundup360 looks at: Steroids may be useful in avoiding dysphagia in anterior cervical discectomy and fusion (ACDF); Perhaps X-Stop ought to stop?; Is cervical plexus block in ACDF the gateway to day case spinal surgery?; Epidural past its heyday?; Steroids in lumbar back pain; Lumbar disc replacement improving; Post-discectomy arthritis

Aim. A retrospective review of the management of adjacent level discectomy and fusion using a Zero-P (Synthes) cage and report of ease of technique and outcomes. Method. Surgical approach to adjacent level cervical disc protrusion with previous anterior cervical discectomy and fusion (ACDF) can be difficult. We review 4 patients who had previous ACDF with cage and plate who developed new onset adjacent level cervical disc prolepses causing myelopathy. A retrospective review of demographic data, symptoms, details of surgery, pre and post operative radiology, pre and postoperative ODI and pain score, length of stay, complications and follow-up data were collected in all patients. Results. Previous ACDF with plate was performed in all 4 patients an average of 11.6 years ago. Two patients had bilateral approaches previously and both had previous vascular injuries. The average duration of current symptoms was 9 months with a mean age of 65 years. All patients presented with myelopathy and two also had radiculopathy. Multiple level ACDF were operated in 2 patients previously. Revision surgery and dissection on the disc level was restricted by the previous plate. Screws from the previous plate fusion were removed adjacent to the level of surgery and discectomy was performed using distractor pins through the screw sites. Following discectomy a Zero-P cage was used to fusion with DBX under image intensifier guidance. The advantage was not to remove the previous plate and keep the dissection over the scar tissue to the minimal. All patients improved in their radicular symptoms with improvement of their hand function in the myelopaths. There was no complication and post operative radiographs were satisfactory. Conclusions. Use of the Zero-P cage for adjacent level discectomy and fusion was safe without disturbing the previous cage and plate fusion or stability