{"title":"Rotation Preserving Fixation for the Treatment of C1 Burst Fracture Combined With Type II Odontoid Fracture: 2 Case Reports and Literature Review.","authors":"Hui Tao, Shanzhong Shao, Kun Yang, Chang Liu, Cailiang Shen, Yinshun Zhang","doi":"10.14444/8646","DOIUrl":"10.14444/8646","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to evaluate the clinical feasibility and effectiveness of a monoaxial screw-rod system and anterior screw fixation for C1 and type II odontoid fractures.</p><p><strong>Methods: </strong>We conducted a retrospective review of 2 consecutive patients with acute C1 and Anderson-D'Alonzo type II odontoid fractures. Both patients underwent treatment using a posterior monoaxial screw-rod system and anterior screw fixation. We reviewed their clinical records, including the visual analog pain scale and Neck Disability Index scores, as well as pre- and postoperative radiographs. Additionally, pre- and postoperative computed tomography images were used to classify the fracture types and assess the C1 to C2 reduction, rotation, and instability.</p><p><strong>Results: </strong>Both patients presented with type II C1 and type II B odontoid fractures, combined with Dickman type II transverse atlantal ligament injuries. All surgical procedures were successfully performed without complications such as vertebral artery injury, neurological deficit, esophageal injury, or wound infection. Both patients achieved almost complete bone healing of the fractures, and C1 to C2 rotation was well preserved (32° and 49°) without atlantoaxial instability after follow-ups of 21 and 25 months, respectively.</p><p><strong>Conclusions: </strong>A monoaxial screw-rod system and anterior screw fixation could be promising surgical strategies for C1 fractures combined with type II odontoid fractures, even in cases involving transverse atlantal ligament injuries. The preservation of C1 to C2 rotation without atlantoaxial instability was observed after fixation. However, extensive case-finding and long-term follow-up are needed to understand the effectiveness of this treatment.</p><p><strong>Clinical relevance: </strong>In order to preserve the C1-C2 rotation, a monoaxial screw-rod system and anterior screw fixation may be more suitable for patients with C1 fractures combined with type II odontoid fractures.</p><p><strong>Level of evidence: 5: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"617-625"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616375/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142509858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Naresh Kumar, Priyambada Kumar, Gabriel Leow Zihui, Leon Seow, Shen Liang, Si Jian Hui, Rohan Parihar, James Hallinan, Balamurugan Vellayappan, Jiong Hao Jonathan Tan
{"title":"Nonmetallic Carbon Fiber-Reinforced Polyetheretherketone Implants Vs Titanium Implants: Analysis of Clinical Outcomes and Influence on Postoperative Radiotherapy Planning in Metastatic Spine Tumor Surgery.","authors":"Naresh Kumar, Priyambada Kumar, Gabriel Leow Zihui, Leon Seow, Shen Liang, Si Jian Hui, Rohan Parihar, James Hallinan, Balamurugan Vellayappan, Jiong Hao Jonathan Tan","doi":"10.14444/8685","DOIUrl":"10.14444/8685","url":null,"abstract":"<p><strong>Background: </strong>Titanium has been the conventional implant material of choice for fixation in both primary and metastatic spine tumor surgeries (MSTS). However, these implants result in artifact generation during postoperative computed tomography or magnetic resonance imaging, resulting in poor planning of radiotherapy (RT) and suboptimal tumor surveillance. Carbon fiber-reinforced polyetheretherketone (CFR-PEEK) implants have gained momentum for instrumentation in MSTS due to their radiolucent properties. In this study, the perioperative outcomes, postoperative imaging artifacts, and dosimetric data of CFR-PEEK implants to titanium implants were compared to assess for potential benefits in postoperative RT planning in patients undergoing MSTS.</p><p><strong>Methods: </strong>This is a retrospective study involving 62 patients who underwent operations for MSTS. The cohort of CFR-PEEK fixations (<i>n</i> = 20) was compared with a series of patients operated using titanium implants (<i>n</i> = 42). Patient-related data, including demographics, tumor pathology and extent of morbidity, intraoperative data, functional outcome, and RT-related data, were recorded for both groups. Primary outcome measures for RT data were amount of artifact generated on postoperative imaging and the time taken to contour them. All patients were followed up postoperatively for a minimum of 2 years or until death, whichever was earlier.</p><p><strong>Results: </strong>Both groups had similar clinical outcomes for pain and overall survival predictability preoperatively (<i>P</i> = 0.786). The mean number of levels instrumented by titanium screws was 5.69 ± 2.64, while for CFR-PEEK screws it was 4.26 ± 1.05. Mean volume of artifact generated during postoperative computed tomography was 73.4 ± 50.43 mm<sup>3</sup> in the titanium group and 20.0 ± 20.7 mm<sup>3</sup> in the CFR-PEEK group (<i>P</i> < 0.001). The mean time taken to contour the artifacts was 17.3 ± 5.84 minutes in titanium group and 9.60 ± 7.17 minutes in CFR-PEEK group (<i>P</i> = 0.049).</p><p><strong>Conclusion: </strong>Our study confirms that CFR-PEEK screws significantly reduce artifact generation and the time taken to contour them during postoperative RT planning while delivering equivalent clinical and functional outcomes as compared with standard titanium implants.</p><p><strong>Level of evidence: 2: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":"18 5","pages":"603-610"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616397/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142630072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Four-Level Cervical Disc Arthroplasty.","authors":"Hsuan-Kan Chang, Chih-Chang Chang, Tsung-Hsi Tu, Yi-Hsuan Kuo, Ching-Lan Wu, Mei-Yin Yeh, Chao-Hung Kuo, Chin-Chu Ko, Li-Yu Fay, Wen-Cheng Huang, Jau-Ching Wu","doi":"10.14444/8603","DOIUrl":"10.14444/8603","url":null,"abstract":"<p><strong>Background: </strong>Multilevel anterior cervical discectomy and fusion inevitably yields a higher chance of pseudarthrosis or require more reoperations than single-level procedures. Therefore, multilevel cervical disc arthroplasty (CDA) could be an alternative surgery for cervical spondylosis, as it (particularly 3- and 4-level CDA) could preserve more functional motility than single-level disc diseases. This study aimed to investigate the clinical and radiological outcomes of 4-level CDA, a relatively infrequently indicated surgery.</p><p><strong>Methods: </strong>The medical records of consecutive patients who underwent 4-level CDA were retrospectively reviewed. These highly selected patients typically had multilevel disc herniations with mild spondylosis. The inclusion criteria were symptomatic cervical spondylotic myelopathy, radiculopathy, or both, that were medically refractory. The clinical outcomes were assessed. The radiographic outcomes, including global and individual segmental range of motion (ROM) at C3-7, and any complications were also analyzed.</p><p><strong>Results: </strong>Data from a total of 20 patients (mean age: 56 ± 8 years) with an average follow-up of 34 ± 20 months were analyzed. All patients reported improved clinical outcomes compared with that of preoperation, and the ROMs at C3-7 were not only preserved but also trended toward an increase (35 ± 8 vs 37 ± 10 degrees, pre- vs postoperation, <i>P</i> = 0.271) after the 4-level CDA. However, global cervical alignment remained unchanged. There was one permanent C5 radiculopathy, but no other neurological deteriorations or any reoperations occurred.</p><p><strong>Conclusion: </strong>For these rare but unique indications, 4-level CDA yielded clinical improvement and preserved segmental motility with low rates of complications. Four-level CDA is a safe and effective surgery, maintaining the ROM in patients with primarily disc herniations and mild spondylosis.</p><p><strong>Clinical relevance: </strong>For patients with mild spondylosis, whose degeneration at the cervical spine is not so severe, CDA is more suitable.</p><p><strong>Level of evidence: 4: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"514-520"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616409/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141088875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gregory M Malham, Dean T Biddau, Thomas A Wells-Quinn, Michael Selby, Geoffrey Rosenberg
{"title":"Early Experience With Novel Molded Allograft Anchors for the Management of Screw Loosening in Elderly Patients With Reduced Bone Density in Primary and Revision Lumbar Surgery.","authors":"Gregory M Malham, Dean T Biddau, Thomas A Wells-Quinn, Michael Selby, Geoffrey Rosenberg","doi":"10.14444/8616","DOIUrl":"10.14444/8616","url":null,"abstract":"<p><strong>Background: </strong>Various strategies have been used to reduce pedicle screw loosening following lumbar instrumented fusion, but all strategies have limitations. In this prospective multicenter cohort study, outcomes of elderly patients with reduced bone density who underwent primary or revision fusion surgery using a novel technique of pedicle screw augmentation with demineralized bone fiber (DBF) anchors were evaluated.</p><p><strong>Methods: </strong>This study included elderly patients (aged >65 years) with dual-energy x-ray absorptiometry-confirmed reduced bone density who required lumbar pedicle screw fixation and were treated with supplemental DBF allograft anchors during primary or revision surgery. The need for DBF anchors was determined by evaluating preoperative computed tomography (CT) scans (for revision surgery) and by the surgeons' tactile feedback intraoperatively during pedicle screw insertion and removal. After determining the pedicle screw void diameter with a sizing instrument, DBF anchors and pedicle screws of the same diameter were placed into the void. CT scans were obtained on postoperative day 2 to assess pedicle breach, pedicle fracture, or anchor material extrusion and at 6 and 12 months postoperatively to assess screw loosening. Thereafter, to minimize radiation exposure, CT scans were only performed for recurrence of pain.</p><p><strong>Results: </strong>Twenty-three patients (79% women; mean age, 74 years) received 50 lumbosacral pedicle screws augmented with DBF anchors. Most surgeries (<i>n</i> = 18, 78%) were revisions, and most anchors were inserted into revision pedicle screw trajectories (<i>n</i> = 33, 66%). Day-2 CT scans revealed no pedicle breach/fracture or extrusion of anchor material. During a mean follow-up of 15 months (12-20 months), no screw loosening was detected, and no patient required pedicle screw revision surgery. There were no adverse events attributable to DBF allografts.</p><p><strong>Conclusions: </strong>DBF allograft anchors appear to be safe and effective for augmenting pedicle screws during revision surgeries in female elderly patients with reduced bone density.</p><p><strong>Clinical relevance: </strong>Clinically, DBF reduced the rate of pedicle screw loosening in patients with reduced bone density. A significant reduction in screw loosening can decrease the need for revision surgeries, which are costly and carry additional risks. Enhanced bone integration from the DBF may promote better healing and long-term stability.</p><p><strong>Level of evidence: 3: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"630-636"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616424/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141311894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Satoshi Hattori, Takashi Tanoue, Futoshi Watanabe, Keiji Wada, Shunichi Mori
{"title":"Quantitative Threshold of Intraoperative Radiological Parameters for Suspecting Oblique Lumbar Interbody Fusion Cage Malposition Triggering Contralateral Radiculopathy.","authors":"Satoshi Hattori, Takashi Tanoue, Futoshi Watanabe, Keiji Wada, Shunichi Mori","doi":"10.14444/8617","DOIUrl":"10.14444/8617","url":null,"abstract":"<p><strong>Background: </strong>This study aimed to clarify the quantitative threshold of intraoperative radiological parameters for suspecting posterior malposition of the oblique lumbar interbody fusion (OLIF) cage triggering contralateral radiculopathy.</p><p><strong>Methods: </strong>We measured the sagittal center and axial rotation angle (ARA) of the cage using postoperative computed tomography (CT) in 130 patients (215 cages) who underwent OLIF. The location of the cage tip was determined from axial magnetic resonance imaging in selected cases based on CT simulations to assess whether the cage was in contact with the contralateral exiting nerve or whether the surgical instruments could contact the nerve during intradiscal maneuvers.</p><p><strong>Results: </strong>The sagittal center of the cages was on average 41.5% from the anterior edge of the endplate (shown as AC/AP value: anterior end plate edge-cage center/anterior-posterior endplate edge ×100%), and posterior cage positioning ≥50% occurred in 14% of the cages. The ARA was -2.9°, and posterior oblique rotation of the cages ≥10° (ARA ≤ -10°) was observed in 13%. CT simulation showed that the cage tip could directly contact the contralateral nerve when the cage was placed deep in the posterior portion ≥50% of the AC/AP values with concomitant posterior axial rotation ≥10° (ARA ≤ -10°), or deep in an extremely rare portion ≥60% of the AC/AP values with posterior axial rotation ≥0° (ARA ≤ 0°). Six percent of the cages (13/215) were placed in these posterior oblique areas (potential contact area: PCA). Three cages in the PCA were in direct contact with the contralateral nerves, and 9 were placed deep just anterior to the nerves. Symptomatic contralateral radiculopathy occurred in 2 cages (2/13/215, 15.3%/0.9%).</p><p><strong>Conclusions: </strong>Two intraoperative radiological parameters (AC/AP and ARA) measurable during OLIF procedures may become practical indicators for suspecting cage malposition in PCA and may be available when determining whether to consider cage revision intraoperatively to a more ventral disc space or anteriorly from the opposite endplate edge.</p><p><strong>Level of evidence: 4: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"521-532"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616371/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141724656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hyun-Jin Park, John I Shin, Ki-Han You, Jason I Yang, Nathan Kim, Yong H Kim, Min-Seok Kang, Sang-Min Park
{"title":"Biportal Endoscopic Transforaminal Lumbar Interbody Fusion: How to Improve Fusion Rate?","authors":"Hyun-Jin Park, John I Shin, Ki-Han You, Jason I Yang, Nathan Kim, Yong H Kim, Min-Seok Kang, Sang-Min Park","doi":"10.14444/8648","DOIUrl":"10.14444/8648","url":null,"abstract":"<p><strong>Background: </strong>Biportal endoscopic transforaminal lumbar interbody fusion (BE-TLIF) is a minimally invasive surgical technique for treating degenerative lumbar spine conditions. It offers advantages such as reduced soft tissue trauma and lower infection rates, but certain technical aspects may be challenging. The current study aims to identify strategies to enhance the fusion rate in BE-TLIF by addressing these specific challenges.</p><p><strong>Methods: </strong>A literature review was conducted on techniques to improve fusion rates in BE-TLIF.</p><p><strong>Results: </strong>The review suggests that lateral-based portals supplemented with medial portals allowed for safe insertion of interbody cages with large footprint. Direct visualization of the disc space with a 30° endoscope assisted with better disc space preparation. Facetectomies performed with osteotomes, rather than burrs, ensured maximum retrieval of autologous bone graft. Utilizing bone morphogenetic proteins with sustained release carriers such as hydroxyapatite can be useful to increase fusion rates of BE-TLIF.</p><p><strong>Conclusions: </strong>To our knowledge, the current literature is the first comprehensive review of strategies to enhance fusion rates in BE-TLIF. The proposed techniques and biological adjuncts are effective means to address key challenges associated with the procedure, and such strategies would potentially shorten the learning curve and improve clinical outcomes. Further clinical studies are required to validate these findings and establish standardized protocols.</p><p><strong>Clinical relevance: </strong>These findings provide practical solutions to overcome common challenges in BE-TLIF. The suggested techniques would reduce the incidence of pseudarthrosis, improve patient outcomes, and ultimately offer a safer and more reliable option for lumbar interbody fusion patients.</p><p><strong>Level of evidence: 5: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"582-588"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616434/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142355883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Matthew Scott-Young, David Nielsen, Evelyne Rathbone, Sukhman Riar, Miller Gantt
{"title":"Efficacy of Stand-Alone Anterior Lumbar Interbody Fusion With PEEK Cages, BMP-2, and Allografts for Treating Discogenic Low Back Pain: Assessing Clinical and Radiographic Outcomes.","authors":"Matthew Scott-Young, David Nielsen, Evelyne Rathbone, Sukhman Riar, Miller Gantt","doi":"10.14444/8679","DOIUrl":"10.14444/8679","url":null,"abstract":"<p><strong>Background: </strong>Chronic low back pain secondary to degenerative disc disease is a significant public health issue worldwide, contributing to substantial health care burdens and patient disability. Anterior lumbar interbody fusion (ALIF) has emerged as a promising surgical solution, offering benefits such as disc height restoration, reduced neural compression, and improved spinal alignment. This study evaluates the efficacy of stand-alone ALIF using polyetheretherketone (PEEK) cages, structural femoral head allografts, and recombinant human bone morphogenetic protein-2 (rhBMP-2) in treating discogenic low back pain caused by degenerative disc disease.</p><p><strong>Methods: </strong>This prospective case series study included 1335 patients who underwent stand-alone ALIF by a single surgeon. The surgical construct involved PEEK cages with structural femoral allograft dowels and rhBMP-2, supplemented by anterior fixation. Patient-reported outcome measures, including the visual analog scale for back and leg pain, the Oswestry Disability Index, the Roland-Morris Disability Questionnaire, and patient satisfaction, were monitored over 12 months.</p><p><strong>Results: </strong>The overall fusion rate was 99.6%, with pseudoarthrosis occurring in 0.2% of patients. Lower fusion rates were observed in patients older than 65 years and those using the Brantigan cage. Significant improvements were seen in visual analog scale for back and leg pain, Oswestry Disability Index, and Roland-Morris Disability Questionnaire scores from baseline, with most scores exceeding the substantial clinical benefit thresholds. More than 85% of patients reported \"Excellent\" or \"Good\" outcomes.</p><p><strong>Conclusions: </strong>Stand-alone ALIF, augmented with rhBMP-2 and structural femoral head allografts, can enhance mechanical stability, fusion rates, and radiographic assessment. This integrated approach achieves successful spinal fusion and positive clinical outcomes for patients with refractory discogenic low back pain.</p><p><strong>Clinical relevance: </strong>Stand-alone ALIF with PEEK cages, structural femoral head allografts, and rhBMP-2 demonstrates high fusion rates and significant clinical improvements in patients with discogenic low back pain. This approach enhances spinal stability and promotes biological healing, making it a reliable and effective surgical option.</p><p><strong>Level of evidence: 4: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"502-513"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616443/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142583750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Feasibility of C2 Lamina Screw Placement in a New Zealand Cohort: Computed Tomography Analysis According to Ethnicity and Gender.","authors":"Richard N Storey, Joseph F Baker","doi":"10.14444/8600","DOIUrl":"10.14444/8600","url":null,"abstract":"<p><strong>Background: </strong>Previous analyses have suggested variations in cervical spine canal morphology according to ethnicity, possibly in part due to variations in the posterior elements. The potential for these variations to affect the placement of instrumentation is uncertain. The aim of this study was to report on the feasibility of C2 lamina screw insertion in a New Zealand cohort including analysis of Māori, the indigenous people of New Zealand.</p><p><strong>Methods: </strong>A trauma computed tomography database was accessed to identify suitable images. On axial images, where the isthmus was at its widest, the outer diameter (OD) and inner diameter (ID) of the lamina were measured. Screw length was measured from a proposed entry point to the contralateral junction of the lamina and lateral mass. The spinolaminar angle was measured as the angle subtended by the screw trajectory and midsagittal plane. A 5.5-mm OD was accepted as a threshold for the feasibility of lamina screw placement.</p><p><strong>Results: </strong>One hundred eighty-seven images were assessed: 115 New Zealand European and 72 Māori. The mean age of the cohort was 41.9 years (SD 19.6), and most patients (64%) were men. For the entire cohort, mean OD was 6.6 and 6.8 mm on the right and left, respectively; the mean inner diameter was 3.5 and 3.8 mm; mean screw length was 31.5 and 31.5 mm; and mean spinolaminar angle was 46.0° and 46.1°. C2 lamina screw placement was feasible in a majority of patients. Considering only Māori patients, placement was feasible in 96% of right and 94% of left laminae in men but 72% of right and 72% of left laminae in women.</p><p><strong>Conclusions: </strong>In a majority of patients, C2 lamina screw placement is feasible. However, advanced imaging must be carefully assessed preoperatively because data suggest that Māori women may not necessarily have optimal anatomy.</p><p><strong>Clinical relevance: </strong>Care needs to be taken when assessing and planning surgery inpatients of different ethnicities because variations may exist in the morphology of the posterior elements of C2, leading to variation in optimal fixation strategy.</p><p><strong>Level of evidence: 3: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"471-476"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616403/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140871500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masashi Uehara, Shota Ikegami, Hiroki Oba, Yoshinari Miyaoka, Takayuki Kamanaka, Terue Hatakenaka, Takuma Fukuzawa, Koji Hayashi, Jun Takahashi
{"title":"Characteristics of Screw Perforation and Screw Loosening in Atlantoaxial Transarticular Fixation Using a Preoperative Computed Tomography-Based Navigation System.","authors":"Masashi Uehara, Shota Ikegami, Hiroki Oba, Yoshinari Miyaoka, Takayuki Kamanaka, Terue Hatakenaka, Takuma Fukuzawa, Koji Hayashi, Jun Takahashi","doi":"10.14444/8604","DOIUrl":"10.14444/8604","url":null,"abstract":"<p><strong>Background: </strong>Atlantoaxial transarticular fixation, also called the Magerl technique, is said to be the most robust biomechanical method of fixation of the atlantoaxial vertebrae. However, the procedure carries a risk of spinal cord and vertebral artery injury during the insertion process, especially in patients with a high-riding vertebral artery. In this study, a computed tomography (CT)-based navigation system was used for preoperative planning and insertion. This investigation sought to determine the rate and direction of screw perforation as well as the incidence of screw loosening in computer-assisted atlantoaxial transarticular fixation.</p><p><strong>Methods: </strong>Sixty patients (31 men and 29 women; mean ± SD age: 65.3 ± 19.6 years) who received atlantoaxial transarticular screw insertion with preoperative CT navigation were analyzed. We investigated screw position and loosening by CT at the final follow-up.</p><p><strong>Results: </strong>Of the 108 screws inserted, the rate of Grade 2 or higher perforation was 4.6% (5/108). Nine of 81 (11.1%) screws inserted into the 44 patients who were followed for at least 6 months showed loosening. Logistic regression analysis revealed that unilateral insertion (odds ratio: 8.50, 95% confidence interval: 1.53-47.2, <i>P</i> = 0.014) was significantly associated with the incidence of screw loosening.</p><p><strong>Conclusions: </strong>The screw perforation rate of Grade 2 or higher in computer-assisted atlantoaxial transarticular screw fixation was 4.6%, with comparable frequencies of perforation direction. Unilateral insertion was a significant independent factor associated with screw loosening, which occurred in 11.1% of insertions.</p><p><strong>Clinical relevance: </strong>Spine surgeons should follow up with patients with caution because screws with unilateral insertion are prone to loosening.</p><p><strong>Level of evidence: 4: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"477-481"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616429/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140923525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dae-Woong Ham, Jeuk Lee, Byung-Taek Kwon, Yisack Yoo, Sang-Min Park, Kwang-Sup Song
{"title":"Comparison of Postoperative Epidural Hematoma Formation Between Biportal Endoscopic Spine Surgery and Conventional Microscopic Surgery: A Randomized Controlled Trial.","authors":"Dae-Woong Ham, Jeuk Lee, Byung-Taek Kwon, Yisack Yoo, Sang-Min Park, Kwang-Sup Song","doi":"10.14444/8578","DOIUrl":"10.14444/8578","url":null,"abstract":"<p><strong>Background: </strong>Biportal endoscopic spine surgery (BESS) has become widely recognized as a minimally invasive method for spinal decompression and discectomy. However, postoperative epidural hematoma (POEH) presents a significant risk in spinal surgery due to its potential to compress neural elements and lead to neurological deficits. This study compares the clinical and radiological outcomes of BESS with those of conventional microscopic surgery.</p><p><strong>Methods: </strong>In this single-center, single-blinded, actively controlled randomized clinical trial, 46 patients undergoing single-level posterior decompression or discectomy for spinal stenosis or herniated intervertebral discs were enrolled. Participants were randomly allocated to either the conventional microscopic surgery group or the BESS group. Experienced spine surgeons performed all procedures. Postoperative magnetic resonance imaging assessments were conducted following the removal of the drain system. Outcome measures included the cross-sectional area (CSA) of the dura sac and POEH, as well as the incidence of neurological deficits.</p><p><strong>Results: </strong>The demographic and baseline characteristics of the patients were similar across the 2 groups, with 24 in the conventional group and 22 in the BESS group. There were no significant differences in the preoperative and postoperative CSA of the dura sac between the groups. However, the BESS group exhibited a significantly larger CSA of POEH (0.36 ± 0.34 cm²) compared with the conventional group (0.17 ± 0.15 cm², <i>P</i> = 0.033). Despite this higher incidence of POEH, there was no corresponding increase in neurological deficits or revision surgeries.</p><p><strong>Conclusion: </strong>The findings indicate that while BESS achieves decompression comparable to that of conventional microscopic surgery, it is associated with a higher incidence of epidural hematomas. Importantly, these hematomas did not result in an increased rate of neurological deterioration or the need for surgical interventions. Further studies with larger sample sizes and extended follow-up are required to confirm these results and further refine the BESS technique.</p><p><strong>Clinical relevance: </strong>Despite a higher incidence of epidural hematomas, BESS offers comparable decompression to microscopic surgery without increased neurological risks, making it a viable, less invasive option for patient care.</p><p><strong>Level of evidence: 2: </strong></p>","PeriodicalId":38486,"journal":{"name":"International Journal of Spine Surgery","volume":" ","pages":"533-539"},"PeriodicalIF":1.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11616404/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142394084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}