Do Osteobiologics Augment Fusion in Anterior Cervical Discectomy and Fusion Surgery Performed With Mechanical Interbody Devices (Polyether ether ketone, Carbon Fiber, Metal Cages) and is the Fusion Rate Comparable to that With Autograft? A Systematic Review.

STUDY DESIGN: Systematic Review of the Literature. OBJECTIVE: The purpose of this study was to perform a systematic review describing fusion rates for anterior cervical discectomy and fusion (ACDF) using autograft vs various interbody devices augmented with different osteobiologic materials. METHODS: A systematic review limited to the English language was performed in Medline, Embase and Cochrane library using Medical Subject Heading (MeSH) terms. Studies that evaluated fusion after ACDF using autografts and osteobiologics combined with PEEK, carbon fibre, or metal cages were searched for. Articles in full text that met the criteria were included in the review. The main outcomes evaluated were the time taken to merge, the definition of the fusion assessment, and the modality of the fusion assessment. The risk of bias of each article was assessed by the MINORS score or ROB 2.0 depending on the randomisation process. RESULTS: The total number of references reviewed was six hundred and eighty-two. After applying the inclusion criteria, 54 were selected for the retrieval of the full text. Eight studies were selected and included for final analysis in this study. Fusion rates were reported between 83.3% and 100% for autograft groups compared to 46.5% and 100% for various interbody device/osteobiological combinations. The overall quality of the evidence in all radiographic fusion studies was considered insufficient due to a serious risk of bias. CONCLUSION: Mechanical interbody devices augmented with osteobiologics performed similarly to autografts in terms of reliability and efficacy. Their time to fusion and fusion rate were comparable to autografts at the end of the final follow-up.

Complications With Demineralized Bone Matrix, Hydroxyapatite and Beta-Tricalcium Phosphate in Single and Two-Level Anterior Cervical Discectomy and Fusion Surgery.

STUDY DESIGN: Systematic literature review. OBJECTIVES: To analyze the evidence available reporting complications in single or two-level anterior cervical discectomy and fusion (ACDF) using a demineralized bone matrix (DBM), hydroxyapatite (HA), or beta-tricalcium phosphate (ß-TCP). METHODS: A systematic review of the literature using PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov databases was performed in August 2020 to identify studies reporting complications in one or two-level ACDF surgery using DBM, HA, or ß-TCP. The study was reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. RESULTS: A total of 1857 patients were included, 981 male and 876 female, across 17 articles; 5 prospective, and 12 retrospectives. We noted heterogeneity among the included studies concerning the study design and combination of graft materials utilized in them. However, we noted a higher incidence of adjacent segment disease (17.7%) and pseudoarthrosis (9.3%) in fusion constructs using DBM. Studies using ß-TCP reported a higher incidence of pseudoarthrosis (28.2%) and implant failures (17.9%). CONCLUSIONS: Degenerative cervical conditions treated with one or two-level ACDF surgery using DBM, HA, or ß-TCP with or without cervical plating are associated with complications such as adjacent segment disease, dysphagia, and pseudarthrosis. However, consequent to the study designs and clinical heterogeneity of the studies, it is not possible to correlate these complications accurately with any specific graft material employed. Further well-designed prospective studies are needed to correctly know the related morbidity of each graft used for achieving fusion in ACDF.

Is There a Role for Preoperative Local Infiltration of Tranexamic Acid in Elective Spine Surgery? A Prospective Randomized Controlled Trial Analyzing the Efficacy of Intravenous, Local Infiltration, and Topical Administration of Tranexamic Acid.

STUDY DESIGN: Randomized control trial. OBJECTIVE: The purpose of the study is to evaluate the safety and efficacy of tranexamic acid in reducing blood loss when administered through various routes in instrumented spine surgeries. METHODS: A total of 104 patients undergoing instrumented spine surgery were randomly assigned to 4 groups (n = 26 in each group). Groups included (1) ivTXA-intravenous administration of tranexamic acid (TXA) 1 hour prior to surgery, (2) loTXA-local infiltration of TXA bilaterally into the paraspinal musculature prior to incision, (3) tTXA-topical application of TXA just before wound closure, and (4) control group. Outcome measures included intraoperative blood loss, postoperative blood loss, need for blood transfusion, length of hospital stay, and hematological parameters. RESULTS: All the 3 different modes of TXA administration were found to be effective in reducing blood loss in the treated groups compared with the control group. Intraoperative blood loss was significantly reduced in ivTXA (223.6 ± 40.1 mL, P < .0001) and loTXA (256.07 ± 119 mL, P = .0039) groups when compared with controls (344 ± 88.5 mL).The postoperative blood loss was least in tTXA followed by ivTXA, loTXA, and controls. There was 67% reduction in need for blood transfusion in tTXA group, 55.5% reduction in ivTXA group, and 33% reduction in loTXA group when compared with the control group. CONCLUSION: In instrumented spine surgery, ivTXA and loTXA were found to be equally effective in reducing the intraoperative blood loss. The tTXA has better postoperative blood conserving effects. This is the first study to detail about safety and efficacy on local infiltration of TXA in spine surgery, which is an effective and safe method for reducing intraoperative blood loss.

Do Prophylactic Antibiotics Reach the Operative Site Adequately?: A Quantitative Analysis of Serum and Wound Concentrations of Systemic and Local Prophylactic Antibiotics in Spine Surgery.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: To analyze the serum and drain concentrations of antibiotics administered by two different routes and compare the results. SUMMARY OF BACKGROUND DATA: Systemic antibiotics are expected to reach the surgical site and maintain adequate concentrations of the drug to prevent infection. However, it is unknown whether systemically administered antibiotics reach and maintain such adequate concentrations at the surgical wound or not. METHODS: Forty patients undergoing elective spine surgery received intra-wound Vancomycin (1 GM) before the wound closure and single dose of intravenous Gentamycin (80MG) immediately after surgery. Blood and drain samples were collected postoperatively to estimate serum and drain concentrations of Gentamycin and Vancomycin. Drug Estimation Protocol: Drug concentrations were estimated by ADVIA Centaur CP immunoassay (direct chemiluminescence). Gentamycin and vancomycin in the test samples competes with their respective acridinium ester-labeled gentamicin and vancomycin derivatives for monoclonal mouse anti-gentamycin and anti-vancomycin antibodies which are covalently coupled to paramagnetic particles in the solid phase. RESULTS: Gentamycin attained peak serum levels at 6 hours following administration with an average value of 9.90 ±â€Š3.1 µg/mL which was decreased to 6.76 ±â€Š2.6 µg/mL at 12 hours and steadily declining thereafter. Even though, the drug concentrations in the drain collection from the wound also attained peak levels at 6 hours, the drug concentrations were lower (3.75 ±â€Š1.4 µg/mL) than that of serum concentrations and inadequately attained the recommended target peak of Gentamycin (4-12 µg/mL).Wound levels of local vancomycin were significantly higher at 6 hours (413.4 ±â€Š217.3 µg/mL) and well maintained even at 72 hours. Serum vancomycin levels were observed to be highest at 6 hours in negligible concentrations of 6.06 ±â€Š2.2 µg/mL. CONCLUSION: After prophylactic systemic administration of the antibiotics, the antibiotic drug concentrations in the wound are much lower than the serum concentrations at any given time. After local intra-wound application of antibiotics, the drug concentrations in the wound are well maintained even after 72 hours. LEVEL OF EVIDENCE: 3.

Surgeon's Neck Posture during Spine Surgeries: "The Unrecognised Potential Occupational Hazard".

STUDY DESIGN: Observational study. PURPOSE: The purpose of this study is to analyze the surgeon's neck postures while performing lumbar spinal surgeries. OVERVIEW OF LITERATURE: Lumbar spinal surgeries are on rising trend, and with increase in number of procedures, the average time spent by a spine surgeon performing surgical procedures is also increasing. The effect of operating posture on the surgeon's neck is largely unknown. From the studies conducted on usage of smartphones, abnormal neck postures, especially the forward head posture (FHP), were found to adversely affect the cervical spine of individuals. The present study analyzes the neck position of spine surgeons during lumbar spine surgeries. METHODOLOGY: Sixty video recordings (25 open transforaminal lumbar interbody fusions [TLIFs] and 35 lumbar decompression [LD] procedures - 15 with headlight and 20 with operating microscope) of surgeries performed by three spine surgeons of different heights were analyzed. Running videos of the surgeries were recorded concentrating on the surgeons with reflective markers taped to their surface landmarks corresponding to C7 spinous process, tragus of the ear, and outer canthus of the eye. Video recordings were standardized by a fixed video recorder in the same operating theater. Snapshots from the video were obtained whenever the surgeon changes the position. Head flexion angle (HFA), neck flexion angle (NFA), and cervical angle (CA) were measured and analyzed. RESULTS: During TLIF, HFA and NFA were significantly higher during the phases of decompression and fusion (P < 0.05). The average CA of all surgeons was lower, thereby adversely affecting the cervical spine (20.15° ± 5.05°). During LD, CA showed significant difference between usage of microscope and headlight (P < 0.001). CONCLUSION: Surgeon's FHP is frequently caused by a compromise between the need to perform surgery with hands, without elevating the arms, and simultaneous control of gaze at surgical field. The usage of microscope was found to reduce the stress on neck while performing surgery.