Mohammad El-Sharkawi

Study Design: Narrative review. Objectives: To clarify definitions and classifications regarding the diagnosis, medical managementand role of spinal surgery in the treatment of primary pyogenic spinal infections. Methods: A comprehensive review of the MEDLINE, OVID, Embase, Google Scholar and Cochrane Database of Systematic reviews was conducted to characterize historical means of diagnosing spondylodiscitis and explore current controversies in the management of primary pyogenic spinal infections. This includes evaluating the role of aggressive early surgical intervention versus conservative maximal medical management. The AO Spine Primary Infection Classification System is introduced and framed against this historical backdrop. Results: Surgical intervention in the treatment of pyogenic spinal infection is traditionally reserved for cases of neurological deficit, mechanical instability, or to facilitate microbiological diagnosis. Contemporary studies contend that early surgical debridement leads to superior source control and improved functional as well as neurological outcomes. We note that the majority of these studies are retrospective in nature and that there is a consistent lack of a clear definition of spondylodiscitis or stage of pyogenic primary spinal infection, variation in antibiotic regimens and lack of clear definitions as to what constitutes early or late surgery. Conclusions: Patients who suffer from pyogenic primary spinal infections present at different time courses along their illness and therefore existing studies examining early or late surgical interventions are confounded by this heterogeneity. Existing studies remain disparate due to the absence of a reliable classification. The AO Spine Primary Infection Classification System presents a universal and standardized means of communicating severity of spinal infections.

Study Design: Narrative review. Objective: To clarify nuances when applying the AO Spine Primary Infection Classification. Methods: The international validation of the AO Spine Primary Infection Classification System was successful but recurring themes caused confusion. This included the exact definition and reasons for infections to transition between categories, definition of canal involvement or neural compression and whether an epidural infection superimposed on degenerative disease escalates infection severity. There was uncertainty regarding handling of multi-level or junctional infection and clinicians encountered difficulty applying the modifiers. Results: The difference between a Type 0 and Type 1 infection is reasonably distinct given the former is purely extraspinal whilst the latter involves spondylodiscitis or osteomyelitis without canal involvement. Type 2 infections include those with any canal involvement, regardless of whether CSF effacement occurs, in the absence of neural compression. The spinal canal is defined as the compartment dorsal to the posterior longitudinal ligament and excludes infections that are ventral to this ligament but bow into the canal. Any neural compression of the thecal sac centrally or within the foramen escalates categorization to a Type 3 infection. Conclusions: Primary spinal infections have the potential to rapidly progress and cause devastating neurological deficits. The introduction of the AO Spine Primary Infection Classification establishes a universal language to communicate disease severity. We clarify common nuances encountered during international validation of this system including definition of canal involvement and relevance of CSF effacement, whether foraminal involvement constitutes neural compression and the nomenclature concerning multi-level or junctional disease.

Was not provided for this article.

Study Design: Cross-sectional survey study. Objectives: To identify clinical knowledge gaps in spinal trauma and infection and assess use of AO Spine tools and recommendations. Methods: A 33-item online survey was distributed to AO Spine members by email and nonmembers through social media. Responses addressed demographics, case volume, knowledge gaps, and preferred educational formats. Descriptive statistics and regional comparisons using chi-squared or Fisher’s exact tests were performed. Signficance was at the P < 0.05 level. Results: Of 431 respondents, 412 completed at least one survey section and were included; the overall response rate could not be determined because the number of individuals who received or viewed the survey invitation was unavailable. Most respondents were orthopedic (61.2%) or neurosurgical (35.4%) surgeons. Leading priorities were osteoporotic spinal fractures (49.0%), spinal infection (48.3%), and fragility-associated low-energy sacropelvic fractures (40.3%). Regional variation was significant for sacropelvic fragility fractures ( P = 0.038) and osteoporotic fractures ( P = 0.028). Key gaps included bone quality optimization and surgical treatment for sacropelvic fragility fractures, comparison of techniques for osteoporotic fractures, and spinal infection algorithms. AO Spine Injury Classifications were routinely used by 89.5% of respondents. Use of the separate AO Spine–DGOU Osteoporotic Fracture Classification and AO Spine Primary Spine Infection Classification was reported by 35.7% and 18.7%, respectively, while PROST and CROST use was reported by 17.4% and 14.5%. Conclusions: Surgeons reported a need for standardized, evidence-based algorithms and accessible educational resources for osteoporotic fractures, spinal infection, and fragility-associated low-energy sacropelvic fractures.

Study Design.: Global cross-sectional survey Objective.: To establish a surgical algorithm for upper cervical spine injuries using the AO Spine Upper Cervical Injury Classification (UCIC) system, defining operative thresholds using a novel proposed Upper Cervical AO-Spine Injury Score (UC-AOSIS). Summary of Background Data.: The AO Spine UCIC system provides a hierarchical, morphology-based classification for upper cervical spine trauma. Although reliability has been previously demonstrated, there is no established consensus on operative versus nonoperative management for specific UCIC subtypes. Methods.: A survey including clinical vignettes of UCIC injury types (A3, B1, B2, B3, and C1), modified by neurological grades (N0-N4) and case-specific modifiers (M1-M5), was distributed to orthopaedic spine surgeons/neurosurgeons across AO Spine regions. Surgeons were asked whether a patient should undergo operative/nonoperative management for each scenario. Decision-making patterns were analyzed to identify severity thresholds, which were incorporated into a scoring framework. Results.: A total of 159 surgeons responded. An operative consensus threshold of 70% agreement was determined by AO Spine Knowledge Forum Trauma methodology, with consensus reached for most injury patterns. Across all regions and surgical subspecialties, fracture patterns with UC-AOSIS scores ≤3 were consistently managed nonoperatively, while those with scores ≥5 were treated operatively. Injuries given a score of 4 demonstrated variable surgeon preference, falling into an “equipoise” zone without strong consensus for either approach. Conclusion.: The AO Spine Upper Cervical Classification System, combined with international multispecialty surgeon input, enabled creation of a novel surgical algorithm for upper cervical trauma (UC-AOSIS). High-severity morphology (B3, C1), unstable B2 subtypes, and any associated neurologic impairment (N2-N4) meet operative thresholds. Level of Evidence.: 4

Study design: Literature review with clinical recommendations. Objective: To highlight impactful studies on the management of spinal tuberculosis (STB), identified by the AO Spine Knowledge Forum Trauma and Infection group, with recommendations for their integration into clinical practice. Methods: Four studies addressing key phases of STB management — imaging diagnosis, laboratory diagnosis, surgical indication and approach, and imaging-based healed status — were reviewed. Consensus recommendations of the KF opinion leaders were graded as strong or conditional following the GRADE methodology. Results: Altini et al evaluated the diagnostic value of MRI and FDG-PET/CT in spondylodiscitis including STB; we conditionally recommend FDG-PET/CT as an adjunctive imaging modality when MRI is inconclusive, contraindicated, or limited by artifact. Hu et al developed a multivariable laboratory prediction model based on seven routine indices for early STB diagnosis, achieving an AUC of 0.947; we conditionally recommend this model as an adjunctive screening tool when definitive microbiological testing is delayed or unavailable. Tang et al compared anterior-only, posterior-only, and combined surgical approaches in thoracolumbar STB; we conditionally recommend a posterior-only approach as the preferred surgical strategy in most cases requiring operative treatment. Mittal et al evaluated FDG-PET/CT and contrast MRI for defining healed status and guiding treatment completion; we conditionally recommend FDG-PET/CT as an adjunctive tool when the treatment endpoint remains uncertain or MRI is limited by metallic implants. Conclusion: This review provides spine surgeons and clinicians with evidence-based, expert-graded recommendations to enhance standardization and effectiveness across the key clinical decision points in spinal tuberculosis management.

Study Design: Retrospective review of prospectively collected data. Objective: The objective of this study is to compare the clinical outcomes of patients treated with or without a stabilizing brace for neurologically intact thoracolumbar burst fractures. Summary of Background Data: The role of bracing in the nonoperative management of thoracolumbar burst fractures remains controversial. Methods: This post hoc subanalysis of a prospective, multicenter study examined patients with type A3 or A4 thoracolumbar burst fractures without neurologic deficit who were treated nonoperatively with either a stabilizing brace or no brace. The primary outcomes were achieving the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) in the Oswestry Disability Index (ODI). Secondary outcomes included return to work, mental health, pain, and overall patient satisfaction with treatment. Results: In total, 76 patients met inclusion criteria for the study including 48 patients (63%) treated with bracing and 28 (37%) patients treated without bracing. Time-to-event analyses indicated no differences in achieving MCID or PASS in ODI between patients with and without a stabilizing brace (all P >0.05). Significantly better scores were seen in the bracing group when compared with the non-bracing group at 3 months in terms of pain and overall satisfaction with care (both P P <0.05). Conclusions: We found no statistically significant differences in PROMs, return to work, or satisfaction at 1 year between patients treated with or without bracing. However, bracing was associated with improved pain, anxiety/depression scores, and satisfaction in the early period after injury. Bracing may offer advantages in terms of patient comfort and mental health in the short term but likely has no bearing on longer-term outcome in neurologically intact patients with thoracolumbar burst fractures. Level of Evidence: Level III.

Study Design: Cross-sectional Survey-Based Study. Objectives: Existing classification systems for upper cervical spine trauma lack structured guidance for clinical decision-making. While the AO Spine Upper Cervical Injury Classification (UCIC) provides a comprehensive framework, it lacks an accompanying injury score. This study aimed to develop the AO Spine Upper Cervical Injury Score (UCIS) based on global perceived injury severity scores (ISS). Methods: Data from a global survey of 159 surgeons were analyzed. Surgeons assigned a perceived ISS (0-100) to each UCIC variable relative to the need for surgical stabilization. Median ISS values for injury morphology, neurologic status, and modifiers were translated into an integer-based scoring system. Results: Stable Type A injuries were assigned 1 point, while unstable ligamentous and translational injuries received higher scores (eg, Type IIB = 5 points; Type IC = 7 points). For neurologic status, N0 received 0 points, N1/N2 received 1 point, and N3/4 were consolidated to 6 points. Unexamined patients (NX) were allocated 3 points. Modifiers M1 (nonunion risk) and M3 (comorbidities) were assigned 3 points (ISS 60.0), while M2 (instability received 4 points (ISS 75.0). Conclusion: The AO Spine UCIS is a simplified scoring system that translates global consensus on injury severity to a clinically applicable score. It was built upon a foundational survey demonstrating minimal geographic or experiential variability in severity ratings. The UCIS serves as a clinically relevant tool to complement the validated AO Spine UCIC system and provides the necessary framework for the future development of a treatment algorithm for upper cervical spine injuries.

Study Design: Multicenter reliability and validation study. Objectives: To adapt and validate the Spinal Instability Spondylodiscitis Score (SISS) to create a practical and reliable classification system for assessing spinal instability in pyogenic spondylodiscitis. Methods: The original SISS was modified through structured consensus meetings within the AO Spine Trauma and Infection Knowledge Forum, resulting in the modified SISS (mSISS). The mSISS incorporates four parameters—location, extent of bone lesion, spinal alignment, and mechanical pain—to classify lesions as stable, potentially unstable, or unstable using computed tomography (CT) and clinical data. Fifteen experienced spine surgeons independently evaluated ten representative cases in two rating sessions. Intra- and interrater reliabilities were calculated using intraclass correlation coefficients (ICC) and Fleiss’ Kappa. The gold standard was established by consensus of five expert spine surgeons. Results: The mSISS demonstrated excellent intrarater reliability for the total score (ICC 0.90, 95% CI 0.84-0.96). Interrater reliability for the total score was 0.87 (95% CI 0.77-0.97) in the first assessment and 0.89 (95% CI 0.80-0.98) in the second. Reliability of individual parameters ranged from moderate to excellent, with spinal alignment showing the highest variability but remaining within acceptable agreement levels. Agreement with the gold standard ratings was high across all parameters. Conclusion: The mSISS is a simplified and clinically applicable scoring system for the assessment of spinal instability in pyogenic spondylodiscitis, demonstrating strong reliability among expert spine surgeons. Broader international validation is ongoing to support its integration into clinical decision-making.