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Li YA, Shih SL, Chen HC. A M-PEEK rod system to stabilize spinal motion after graded facetectomy: a finite element study. BMC Musculoskelet Disord 2024; 25:838. [PMID: 39438854 PMCID: PMC11494999 DOI: 10.1186/s12891-024-07949-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 10/11/2024] [Indexed: 10/25/2024] Open
Abstract
BACKGROUND Resecting the facet joint to relieve nerve pain can lead to spinal instability, deformity, and abnormal pressure on the anterior of the intravertebral disc. To mitigate these issues, surgeons often limit the amount of bone removed during facetectomy or stabilize the spine by fusion to maintain lumbar stability. This study aimed to assess how a M-PEEK rod system influenced the stability of the lumbar spine during graded facetectomy. METHODS Facetectomy was performed on a validated L1-L5 finite element model which was then simulated both with and without the M-PEEK rod system. RESULTS In extension, models implanted with M-PEEK in the interspinous space of L3/L4 experienced a 35.2% decrease in range of motion (ROM) at L3/L4, while others saw an 8.4-24.8% increase. For axial rotation, the ROM at L3/L4 increased by 2.2-5.4% in models with the M-Rod, and by 4.9-12.9% in models without the implant. In lateral flexion, the ROM at L3/L4 increased by 8.4-14.3% in models without a PEEK M-Rod (facetectomy only), with adjacent segments experiencing a 6.5% decrease in ROM in the implanted models. Overall, the difference in ROM between the intact and implanted models was minimal. CONCLUSIONS Facetectomy involving the removal of 50% or more of the facet joint significantly increases range of motion and maximum intradiscal pressure, potentially accelerating disc degeneration, as shown in our finite element study. Stabilizing the segment with an M-PEEK rod may limit excessive motion, providing stability and maintaining intradiscal pressure closer to that of an intact model.
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Affiliation(s)
- Yi-An Li
- Institute of Translational Medicine and New Drug Development, School of Medicine, China Medical University, Taichung City, 404, Taiwan
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung City, 402, Taiwan
- Orthopaedic Department, School of Medicine, National Yang Ming Chiao Tung University, Taipei City, 112, Taiwan
- Division of Orthopedic Surgery, Changhua Christian Hospital, Changhua City, 500, Taiwan
| | - Shih-Liang Shih
- Department of Orthopaedic Surgery, Taipei City Hospital Zhong-Xing Branch, Taipei City, 112, Taiwan
- Department of Physical Therapy and Assistive Technology, National Yang Ming Chiao Tung University, Taipei City, 112, Taiwan
- Branch of Linsen, Chinese Medicine and Kunming, Taipei City Hospital, Taipei City, 103, Taiwan
| | - Hsin-Chang Chen
- Department of Orthopedic Surgery, Heping Fuyou Branch, Taipei City Hospital, Taipei City, 100, Taiwan.
- Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei City, 112, Taiwan.
- Department of Exercise and Health Sciences, University of Taipei, Taipei City, 111, Taiwan.
- Department of Biomedical Engineering, Chang Gung University, Taoyuan City, 333, Taiwan.
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Shu L, Mu Q, Dai F, Zhao W, Syeda MZ, Wang Y. Contralateral approach using microscope and tubular retractor system for ipsilateral decompression of lumbar degenerative lateral recess stenosis associated with narrow spinal canal. Front Neurol 2024; 15:1387801. [PMID: 38699053 PMCID: PMC11064648 DOI: 10.3389/fneur.2024.1387801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Accepted: 04/03/2024] [Indexed: 05/05/2024] Open
Abstract
Objective To summarize the clinical effect of a single-center retrospective analysis of the contralateral approach with a microscope and tubular retractor system for ipsilateral decompression in patients with lumbar lateral recess stenosis and a narrow spinal canal. Methods A total of 25 patients who underwent ipsilateral decompression surgery via a contralateral approach with microscope and tubular retractor system, performed by one surgeon at a single center were retrospectively examined. The width of the lamina fenestration was compared with the preoperative distance from the root of the spinous process to the dorsal articular facet, the bilateral articular facet change in the suprapedicle notch section on CT scan, and with the changes in transverse and sagittal diameters of the canal area on MRI. Clinical efficacy was assessed using the Japanese Orthopedic Association (JOA), Visual Analog Scale (VAS), and Oswestry Disability Index (ODI) scores. Results In total, 25 patients were treated and the mean intraoperative time was 82.04 ± 12.48 min. There was no nerve injury, cerebrospinal fluid leakage, and infection complications. The postoperative CT revealed that the width of the contralateral laminar fenestration was less than the distance from the root of the spinous process to the dorsal articular facet. The residual widths of the ipsilateral articular facet and contralateral articular facet were greater than 2/3 of the preoperative articular facet width. The transverse and sagittal diameter of canal were significantly increased. The mean follow-up period was 12-16 months, and no recurrence or reoperation incidence were found at the last follow-up. When compared to pre-surgery, the ODI, VAS, and JOA scores were significantly improved after surgery (p < 0.05). Conclusion Based on our single-center retrospective observation of 25 cases and combined with previous literature, the contralateral approach with a microscope and tubular retractor system for ipsilateral decompression in patients with lumbar lateral recess stenosis and a narrow spinal canal can reduce damage to the articular processes, and probably more conducive to the postoperative stability of the lumbar spine. This was a single center retrospective analysis with a small sample size and lacked randomized controlled trials (RCTs). However, larger-scale, multicenter RTCs are required for additional validation.
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Affiliation(s)
- Longfei Shu
- Department of Neurosurgery, Wuxi Clinical College of Anhui Medical University, 904th Hospital of Joint Logistic Support Force of PLA, Wuxi, China
| | - Qingchun Mu
- Department of Neurosurgery, Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Feihu Dai
- Department of Neurosurgery, Wuxi Clinical College of Anhui Medical University, 904th Hospital of Joint Logistic Support Force of PLA, Wuxi, China
| | - Wei Zhao
- Department of Neurosurgery, Wuxi Clinical College of Anhui Medical University, 904th Hospital of Joint Logistic Support Force of PLA, Wuxi, China
| | - Madiha Zahra Syeda
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
- Faculty of Medicine, Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Yuhai Wang
- Department of Neurosurgery, Wuxi Clinical College of Anhui Medical University, 904th Hospital of Joint Logistic Support Force of PLA, Wuxi, China
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Yamato Y, Nagata K, Kawamura N, Higashikawa A, Takeshita Y, Tozawa K, Fukushima M, Urayama D, Ono T, Hara N, Okamoto N, Azuma S, Iwai H, Sugita S, Yoshida Y, Hirai S, Masuda K, Jim Y, Ohtomo N, Nakamoto H, Kato S, Taniguchi Y, Tanaka S, Oshima Y. Comparative Analysis of Microendoscopic and Open Laminectomy for Single-Level Lumbar Spinal Stenosis at L1-L2 or L2-L3. World Neurosurg 2024; 183:e408-e414. [PMID: 38143029 DOI: 10.1016/j.wneu.2023.12.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 12/18/2023] [Accepted: 12/18/2023] [Indexed: 12/26/2023]
Abstract
BACKGROUND Several reports have highlighted comparable surgical outcomes between microendoscopic laminectomy (MEL) and open laminectomy (open) for lumbar spinal stenosis. However, the unilateral approach in MEL may present challenges for the upper lumbar levels, where facet joints are located deeper inside. Our objective was to compare surgical outcomes and radiographic evaluations for single-level decompression cases at L1-L2 or L2-L3 between MEL and open laminectomy. METHODS We analyzed patients who underwent single-level decompression for upper lumbar spinal stenosis at 12 distinguished spine centers from April 2017 to September 2021. Baseline demographics, preoperative, and 1-year postoperative patient-reported outcomes, along with imaging parameters, were compared between the MEL and open groups. To account for potential confounding, patients' backgrounds were adjusted using the inverse probability weighting method based on propensity scores. RESULTS Among the 2487 patients undergoing decompression surgery, 118 patients (4.7%) underwent single-level decompression at L1-L2 or L2-L3. Finally, 80 patients (51 in the MEL group, 29 in the open group) with postoperative data were deemed eligible for analysis. The MEL group exhibited significantly improved postoperative EuroQol 5-Dimension values compared to the open group. Additionally, the MEL group showed a lower facet preservation rate according to computed tomography examination, whereas the open group had a higher incidence of retrolisthesis. CONCLUSIONS Although overall surgical outcomes were similar, the MEL group demonstrated potential advantages in enhancing EuroQol 5-Dimension scores. The MEL group's lower facet preservation rate did not translate into a higher postoperative instability rate.
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Affiliation(s)
- Yukimasa Yamato
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - Kosei Nagata
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - Naohiro Kawamura
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Spine and Orthopedic Surgery, Japanese Red Cross Medical Center, Shibuya City, Tokyo, Japan
| | - Akiro Higashikawa
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Kanto Rosai Hospital, Kawasaki, Kanagawa, Japan
| | - Yujiro Takeshita
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Yokohama Rosai Hospital, Yokohama, Kanagawa, Japan
| | - Keiichiro Tozawa
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Spine Center, Toranomon Hospital, Minato City, Tokyo, Japan
| | - Masayoshi Fukushima
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Spine Center, Toranomon Hospital, Minato City, Tokyo, Japan
| | - Daiki Urayama
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Spinal Surgery, Japan Community Health-Care Organization Tokyo Shinjuku Medical Center, Shinjuku City, Tokyo, Japan
| | - Takashi Ono
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Spinal Surgery, Japan Community Health-Care Organization Tokyo Shinjuku Medical Center, Shinjuku City, Tokyo, Japan
| | - Nobuhiro Hara
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Japanese Red Cross Musashino Hospital, Musashino, Tokyo, Japan
| | - Naoki Okamoto
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Japanese Red Cross Saitama Hospital, Saitama, Japan
| | - Seiichi Azuma
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Japanese Red Cross Saitama Hospital, Saitama, Japan
| | - Hiroki Iwai
- Inanami Spine and Joint Hospital, Shinagawa City, Tokyo, Japan
| | - Shurei Sugita
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Bunkyo City, Tokyo, Japan
| | - Yuichi Yoshida
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Spine Center, National Hospital Organization Sagamihara National Hospital, Sagamihara, Kanagawa, Japan
| | - Shima Hirai
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Spine Center, National Hospital Organization Sagamihara National Hospital, Sagamihara, Kanagawa, Japan
| | - Kazuhiro Masuda
- University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan; Department of Orthopedic Surgery, Tokyo Metropolitan Tama Medical Center, Fuchu, Tokyo, Japan
| | - Yu Jim
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - Nozomu Ohtomo
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - Hideki Nakamoto
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - So Kato
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - Yuki Taniguchi
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan
| | - Sakae Tanaka
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan
| | - Yasushi Oshima
- Department of Orthopaedic Surgery and Spinal Surgery, The University of Tokyo, Bunkyo City, Tokyo, Japan; University of Tokyo Spine Group (UTSG), Bunkyo City, Tokyo, Japan.
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Yu R, Cheng X, Chen B. Percutaneous transforaminal endoscopic decompression with removal of the posterosuperior region underneath the slipping vertebral body for lumbar spinal stenosis with degenerative lumbar spondylolisthesis: a retrospective study. BMC Musculoskelet Disord 2024; 25:161. [PMID: 38378495 PMCID: PMC10877792 DOI: 10.1186/s12891-024-07267-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 02/07/2024] [Indexed: 02/22/2024] Open
Abstract
BACKGROUND Percutaneous transforaminal endoscopic decompression (PTED) is an ideal minimally invasive decompression technique for the treatment of lumbar spinal stenosis (LSS) with degenerative lumbar spondylolisthesis (DLS). The posterosuperior region underneath the slipping vertebral body (PRSVB) formed by DLS is an important factor exacerbating LSS in patients. Therefore, the necessity of removing the PRSVB during ventral decompression remains to be discussed. This study aimed to describe the procedure of PTED combined with the removal of the PRSVB and to evaluate the clinical outcomes. METHODS LSS with DLS was diagnosed in 44 consecutive patients at our institution from January 2019 to July 2021, and they underwent PTED combined with the removal of the PRSVB. All patients were followed up for at least 12 months. The clinical outcomes were evaluated using the visual analog scale (VAS), Oswestry Disability Index (ODI), and modified MacNab criteria. RESULTS The mean age of the patients was 69.5 ± 7.1 years. The mean preoperative ODI score, VAS score of the low back, and VAS score of the leg were 68.3 ± 10.8, 5.8 ± 1.0, and 7.7 ± 1.1, respectively, which improved to 18.8 ± 5.0, 1.4 ± 0.8, and 1.6 ± 0.7, respectively, at 12 months postoperatively. The proportion of patients presenting "good" and "excellent" ratings according to the modified MacNab criteria was 93.2%. The percent slippage in spondylolisthesis preoperatively (16.0% ± 3.3%) and at the end of follow-up (15.8% ± 3.3%) did not differ significantly (p>0.05). One patient had a dural tear, and one patient had postoperative dysesthesia. CONCLUSIONS Increasing the removal of PRSVB during the PTED process may be a beneficial surgical procedure for alleviating clinical symptoms in patients with LSS and DLS. However, long-term follow-up is needed to study clinical effects.
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Affiliation(s)
- Rongbo Yu
- Department of Minimally Invasive Spine Surgery, Chengde Medical University Affiliated Hospital, Chengde, 067000, Hebei, China
| | - Xiaokang Cheng
- Department of Orthopedic, Beijing Tongren Hospital Affiliated to Capital Medical University, Beijing, 100730, China
| | - Bin Chen
- Department of Minimally Invasive Spine Surgery, Chengde Medical University Affiliated Hospital, Chengde, 067000, Hebei, China.
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Sun J, Wang J, Wu R, Zhao Z, Fan B, Cai J, Feng F. Comparison of bone reamer and trephine for foraminoplasty in percutaneous endoscopic lumbar discectomy based on 3D slicer and Digimizer software. J Orthop Surg Res 2024; 19:55. [PMID: 38217013 PMCID: PMC10785399 DOI: 10.1186/s13018-023-04270-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 10/07/2023] [Indexed: 01/14/2024] Open
Abstract
OBJECTIVE To explore the applicability of bone reamer and trephine for foraminoscopy in percutaneous endoscopic lumbar discectomy (PELD), and to provide a theoretical basis for foraminoplasty options in clinical practice. METHODS This study was a prospective cohort study. Sixty-three consecutive patients who underwent PELD for lumbar disc herniation between May 2021 and July 2022 were analysed. Foraminoplasty were performed by bone reamer or trephine. The amount of bone removed and the foramen area enlarged during foraminoplasty by both tools were measured by 3D slicer and Digimizer software, and the numbers of fluoroscopic views were recorded. RESULTS The bone reamer removed less bone in the Superior Articular Process (SAP) than the trephine (t = 17.507, P < 0.001), and the area enlarged by the bone reamer was smaller than that of the trephine (t = 10.042, P = 0.002). The overall numbers of fluoroscopic views were significantly more in the bone reamer group than in the trephine group (t = 19.003, P < 0.001). In the bone reamer group, when the area of preoperative (FPZ) was no less than 54.55 mm2, the mean number of fluoroscopic views significantly decreased (t = 14.443, P = 0.001). CONCLUSION Bone reamer was safer and trephine was more efficient for foraminoscopy in PELD. An area of preoperative (FPZ) of 54.55 mm2 can be used as a critical value: bone reamer reduced the risk for cases above the value, while trephine improved the efficiency for cases less than the value.
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Affiliation(s)
- Jiewei Sun
- Cardiothoracic Surgery Department, The First People's Hospital of Fuyang, No. 429, Beihuan Road, Fuchun Street, Fuyang District, Hangzhou, 311400, Zhejiang, China
| | - Jun Wang
- The orthopaedic, Xiaoshan Hospital Affiliated to Wenzhou Medical University, Hangzhou, Zhejiang, China
| | - Ruiji Wu
- Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 310005, Zhejiang, China
| | - Zhi Zhao
- The orthopaedic, Xiaoshan Hospital Affiliated to Wenzhou Medical University, Hangzhou, Zhejiang, China
| | - Bingkai Fan
- The orthopaedic, Xiaoshan Hospital Affiliated to Wenzhou Medical University, Hangzhou, Zhejiang, China
| | - Jie Cai
- The orthopaedic, Xiaoshan Hospital Affiliated to Wenzhou Medical University, Hangzhou, Zhejiang, China
| | - Fabo Feng
- Center for Plastic and Reconstructive Surgery, Department of Orthopedics, Zhejiang Provincial People's Hospital (Affiliated People's Hospital, Hangzhou Medical College), Hangzhou, Zhejiang, China.
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Pradeep K, Pal B. Effects of open and minimally invasive Transforaminal Lumbar Interbody Fusion (TLIF) surgical techniques on mechanical behaviour of fused L3-L4 FSU: A comparative finite element study. Med Eng Phys 2024; 123:104084. [PMID: 38365336 DOI: 10.1016/j.medengphy.2023.104084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/30/2023] [Accepted: 12/10/2023] [Indexed: 02/18/2024]
Abstract
For predicting the biomechanical effects of the fusion procedure, finite element (FE) analysis is widely used as a preclinical tool. Although several FE studies examined the efficacies of various fusion surgical techniques, comparative studies on Open and minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF) procedures incorporating a follower coordinate system have not been investigated yet. The current FE study evaluates the ranges of motion (ROM) and load distributions of Open-TLIF and MIS-TLIF implanted models, under physiological loading such as compression, flexion, extension and lateral bending. The most noteworthy finding from the investigation is that both the fusion procedures significantly reduced the ROMs of the implanted segment (L3-L4) and full model (L1-L5) by at least 89 % and 44 %, respectively, compared to the intact model. For all loading situations, over 95 % of the implanted models' cancellous bone volume was subjected to von Mises strains ranging from 0.0003 to 0.005. The maximum von Mises strain was observed to be localized on a small amount of cancellous bone volume (<5 %). The likelihood of adjacent segment degeneration is higher in the case of MIS-TLIF due to the higher stress (22-53 MPa) and strain (0.018-0.087) noticed on the upper facet of the L3 vertebra.
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Affiliation(s)
- Kishore Pradeep
- Department of Mechanical Engineering, Indian Institute of Engineering Science and Technology (IIEST), Shibpur, Howrah 711103, West Bengal, India
| | - Bidyut Pal
- Department of Mechanical Engineering, Indian Institute of Engineering Science and Technology (IIEST), Shibpur, Howrah 711103, West Bengal, India.
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Byvaltsev VA, Kalinin AA. [Minimally invasive removal of dumbbell shaped schwannomas with transforaminal lumbar fusion: a retrospective study with a minimum 3-year follow-up]. ZHURNAL VOPROSY NEIROKHIRURGII IMENI N. N. BURDENKO 2024; 88:47-53. [PMID: 38549410 DOI: 10.17116/neiro20248802147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Currently, there are no standards in surgical treatment of dumbbell-shaped tumors of lumbo-foraminal region. OBJECTIVE To evaluate the effectiveness and long-term results of minimally invasive resection of dumbbell-shaped lumbar schwannomas Eden type 2 and 3 combined with transforaminal lumbar interbody fusion and transpedicular stabilization. MATERIAL AND METHODS A retrospective study included 13 patients (8 men and 5 women) with lumbar dumbbell tumors Eden type 2 and 3 who underwent minimally invasive facetectomy through posterolateral anatomical corridor, microsurgical tumor resection and MI TLIF. We analyzed intraoperative parameters, neurological functions (ASIA scale), clinical characteristics (ODI, SF-36), and complications. Resection quality and area of the multifidus muscle were assessed according to MRI data. All patients were followed-up throughout at least 3-year. RESULTS Surgery time was 147 min, blood loss - 118 ml, hospital-stay - 7 days. Clinical parameters significantly improved in the follow-up period: ODI score decreased from 72 to 12 (p=0.004), SF-36 PCS increased from 26.24 to 48.51 (p=0.006) and MCS score increased from 29.13 to 53.68 (p=0.002). According to MRI data, no tumor recurrences and severe muscle atrophy (>30%) were observed after 3 years in all cases. Superficial wound infection occurred in 1 (7.7%) case. There were normal neurological functions (ASIA type E) in all patients. CONCLUSION Minimally invasive facetectomy through posterolateral approach with MI TLIF technology can be used for safe and effective resection of dumbbell-shaped schwannomas Eden type 2 and 3.
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Affiliation(s)
- V A Byvaltsev
- Irkutsk State Medical University, Irkutsk, Russia
- Russian Railways-Medicine Clinical Hospital, Irkutsk, Russia
- Irkutsk State Medical Academy of Postgraduate Education, Irkutsk, Russia
| | - A A Kalinin
- Irkutsk State Medical University, Irkutsk, Russia
- Russian Railways-Medicine Clinical Hospital, Irkutsk, Russia
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Zhang Y, Feng B, Hu P, Dai G, Su W. One-hole split endoscopy technique versus unilateral biportal endoscopy technique for L5-S1 lumbar disk herniation: analysis of clinical and radiologic outcomes. J Orthop Surg Res 2023; 18:668. [PMID: 37689668 PMCID: PMC10492266 DOI: 10.1186/s13018-023-04159-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 09/02/2023] [Indexed: 09/11/2023] Open
Abstract
BACKGROUND Lumbar disk herniation (LDH) is one of the most common diseases of the spine, especially occurring in L4-5 and L5-S1 intervertebral disks, and surgery is a choice when conservative treatment is ineffective. The purpose of this study is to investigate the clinical efficacy and radiologic outcomes of one-hole split endoscopy (OSE) technique versus unilateral biportal endoscopy (UBE) technique in the treatment of L5-S1 lumbar disk herniation (LDH). METHODS A total of 133 patients of a single center surgically treated for L5-S1 LDH between 2019 and 2021 were retrospectively included in this study, of which 70 were treated by UBE technique and the rest were treated by OSE technique. Hospitalization time, operative time, intraoperative blood loss, fluoroscopy times, incision length and related complications were recorded. Bone resection area (BRA), articular process resection rate, range of motion (ROM), sagittal translation (ST), disk height (DH), Visual Analog Score (VAS), Oswestry Disability Index (ODI) and Macnab criteria were used to evaluated the clinical efficacy. RESULTS There was no statistically significant difference in hospitalization time or fluoroscopy times between the two groups. The operation time was shorter in the UBE group than that in the OSE group; however, the incision length was longer. Intraoperative blood loss and BRA were larger in the UBE group than in the OSE group. There was no significant difference in ROM, ST, DH, or postoperative facet resection rate between the two groups. There was no significant difference in ROM, ST, or postoperative facet resection rate compared with preoperative indicators in each group, but there was a significant difference in DH among distinct groups. At any time point, the lower back and leg VAS and ODI in each group were significantly improved compared to those before the operation, with no significant difference between the two groups. There was one case of dural tear in the UBE group. One case of transient hypoesthesia occurred in each of the two groups. The excellent-good rates of the UBE group and the OSE group were 88.6% and 90.5%, respectively. CONCLUSION The OSE technique is an effective minimally invasive surgical option as well as the UBE technique in the treatment of L5-S1 LDH.
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Affiliation(s)
- Yuhong Zhang
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe Er Road, Binzhou, 256603, Shandong, China
| | - Bo Feng
- Department of Neurology, Binzhou Medical University Hospital, No. 661, Huanghe Er Road, Binzhou, 256603, Shandong, China
| | - Peng Hu
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe Er Road, Binzhou, 256603, Shandong, China.
| | - Guohua Dai
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe Er Road, Binzhou, 256603, Shandong, China
| | - Weiliang Su
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe Er Road, Binzhou, 256603, Shandong, China
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Biomechanical and clinical studies on lumbar spine fusion surgery: a review. Med Biol Eng Comput 2023; 61:617-634. [PMID: 36598676 DOI: 10.1007/s11517-022-02750-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 12/22/2022] [Indexed: 01/05/2023]
Abstract
Low back pain is associated with degenerative disc diseases of the spine. Surgical treatment includes fusion and non-fusion types. The gold standard is fusion surgery, wherein the affected vertebral segment is fused. The common complication of fusion surgery is adjacent segment degeneration (ASD). The ASD often leads to revision surgery, calling for a further fusion of adjacent segments. The existing designs of nonfusion type implants are associated with clinical problems such as subsidence, difficulty in implantation, and the requirement of revision surgeries. Various surgical approaches have been adopted by the surgeons to insert the spinal implants into the affected segment. Over the years, extensive biomechanical investigations have been reported on various surgical approaches and prostheses to predict the outcomes of lumbar spine implantations. Computer models have been proven to be very effective in identifying the best prosthesis and surgical procedure. The objective of the study was to review the literature on biomechanical studies for the treatment of lumbar spinal degenerative diseases. A critical review of the clinical and biomechanical studies on fusion spine surgeries was undertaken. The important modeling parameters, challenges, and limitations of the current studies were identified, showing the future research directions.
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Cekov AH, Sailer MHM, Guentchev M. A transfacet approach to the lumbar nerve root canal: technical note. Br J Neurosurg 2022:1-6. [PMID: 36546326 DOI: 10.1080/02688697.2022.2159929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 10/03/2022] [Accepted: 10/25/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Intraforaminal and extraforaminal nerve root compressions caused by disk herniation or stenosis are relatively common causes of lumbar radiculopathy. Currently, the two available surgical treatment methods are decompression from the spinal canal or lateral decompression via the Wiltse approach. OBJECTIVE To describe a novel transosseous approach to the lumbar nerve root canal. METHODS Transfacet foraminotomy was performed in 11 patients with intraforaminal or extraforaminal disk herniation. The outcome was measured using the Patient Satisfaction Index (PSI), need for reoperation, radiographic criteria, and finite element analysis. RESULTS We noted that at the time of dismissal, PSI scores of 1 and 3 were reported by 10 and one patients, respectively. At the last follow-up, 10 patients reported a PSI score of 1 or 2. Two patients required reoperation because of recurrent disk herniation. Two patients underwent computed tomography (CT) postoperatively, which showed the transfacet approach. Intriguingly, a second postoperative CT after one month showed that the hole through the facet joint had shrunk significantly. CONCLUSION A posterior-anterior transfacet approach for intraforaminal or extraforaminal disk herniations using an ellipsoid facetectomy is safe and allows for fast and comfortable decompression of the nerve root without compromising the long-term strength of the facet joint.
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Affiliation(s)
- Asen H Cekov
- Department of Neurosurgery, Trinity Medical Center, Sofia, Bulgaria
| | - Martin H M Sailer
- Department of Neurosurgery and Spine Surgery, Salem-Spital, Bern, Switzerland
| | - Marin Guentchev
- Department of Neurosurgery, Trinity Medical Center, Sofia, Bulgaria
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11
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Complications of Unilateral Biportal Endoscopic Lumbar Discectomy: A Systematic Review. World Neurosurg 2022; 168:359-368.e2. [DOI: 10.1016/j.wneu.2022.10.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 10/09/2022] [Accepted: 10/10/2022] [Indexed: 12/14/2022]
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12
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Meng S, Xu D, Han S, Li G, Wang Y, Shen Y, Zhu K, Lin A, Wang R, Ma X, Zhou C. Fully Endoscopic 360° Decompression for Central Lumbar Spinal Stenosis Combined with Disc Herniation: Technical Note and Preliminary Outcomes of 39 Cases. J Pain Res 2022; 15:2867-2878. [PMID: 36124038 PMCID: PMC9482463 DOI: 10.2147/jpr.s379431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 09/02/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate the outcomes, feasibility, and safety of endoscopic unilateral laminectomy, bilateral decompression and discectomy (Endo-ULBDD) for central lumbar spinal stenosis (CLSS) combined with disc herniation (DH). Methods This study includes 39 patients diagnosed with CLSS combined with DH who met the inclusion criteria and underwent surgery for Endo-ULBDD from April 2020 to March 2021. The mean age of the patients, operation time, hospitalization time, time in bed, and complications were recorded. Patients were followed up for at least 12 months. Visual analog scale (VAS) scores for low-back and lower-limb pain and Oswestry Disability Index (ODI) scores were evaluated preoperatively, before discharge, and at 3, 6, and 12 months postoperatively. To evaluate clinical effectiveness 12 months postoperatively, the modified MacNab criteria were used. Results The mean age of the patients was 59.9 years, the mean operation time was 82.1 minutes, the mean hospitalization time was 3.7 days, and the mean time in bed was 20.9 hours. The mean VAS scores of low-back and lower-limb pain improved from 5.9 and 7.2 to 2.0 and 1.6, respectively (P < 0.05). The ODI score improved from 56.0 to 16.7 (P < 0.05). The overall excellent-good rate of the modified MacNab criteria was 89.7%. Two kinds of complications occurred in 4 patients (10.3%), including 1 patient whose inferior articular process was excessively removed and 3 patients who suffered from postoperative dysesthesia. No other severe complications were noted. Conclusion Endo-ULBDD is a safe, feasible, efficient, and minimally invasive approach to treating CLSS combined with DH.
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Affiliation(s)
- Shengwei Meng
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Derong Xu
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Shuo Han
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Guanghui Li
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Yan Wang
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Yanqing Shen
- Operating Room, Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Kai Zhu
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Antao Lin
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Ruiting Wang
- Medical Insurance Audit Department, Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Xuexiao Ma
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
| | - Chuanli Zhou
- Department of Spinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, People's Republic of China
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13
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Tan QC, Huang JF, Bai H, Liu ZX, Huang XY, Zhao X, Yang Z, Du CF, Lei W, Wu ZX. Effects of Revision Rod Position on Spinal Construct Stability in Lumbar Revision Surgery: A Finite Element Study. Front Bioeng Biotechnol 2022; 9:799727. [PMID: 35071208 PMCID: PMC8766337 DOI: 10.3389/fbioe.2021.799727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/03/2021] [Indexed: 11/28/2022] Open
Abstract
Revision surgery (RS) is a necessary surgical intervention in clinical practice to treat spinal instrumentation–related symptomatic complications. Three constructs with different configurations have been applied in RS. One distinguishing characteristic of these configurations is that the revision rods connecting previous segments and revision segments are placed alongside, outside, or inside the previous rods at the level of facetectomy. Whether the position of the revision rod could generate mechanical disparities in revision constructs is unknown. The objective of this study was to assess the influence of the revision rod position on the construct after RS. A validated spinal finite element (FE) model was developed to simulate RS after previous instrumented fusion using a modified dual-rod construct (DRCm), satellite-rod construct (SRC), and cortical bone trajectory construct (CBTC). Thereafter, maximum von Mises stress (VMS) on the annulus fibrosus and cages and the ligament force of the interspinous ligament, supraspinous ligament, and ligamentum flavum under a pure moment load and a follower load in six directions were applied to assess the influence of the revision rod position on the revision construct. An approximately identical overall reducing tendency of VMS was observed among the three constructs. The changing tendency of the maximum VMS on the cages placed at L4-L5 was nearly equal among the three constructs. However, the changing tendency of the maximum VMS on the cage placed at L2-L3 was notable, especially in the CBTC under right bending and left axial rotation. The overall changing tendency of the ligament force in the DRCm, SRC, and CBTC was also approximately equal, while the ligament force of the CBTC was found to be significantly greater than that of the DRCm and SRC at L1-L2. The results indicated that the stiffness associated with the CBTC might be lower than that associated with the DRCm and SRC in RS. The results of the present study indicated that the DRCm, SRC, and CBTC could provide sufficient stabilization in RS. The CBTC was a less rigid construct. Rather than the revision rod position, the method of constructing spinal instrumentation played a role in influencing the biomechanics of revision.
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Affiliation(s)
- Quan-Chang Tan
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China.,Department of Orthopaedics, Air Force Hospital of Eastern Theater Command, Nanjing, China
| | - Jin-Feng Huang
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Hao Bai
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Zi-Xuan Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, China
| | - Xin-Yi Huang
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Xiong Zhao
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Zhao Yang
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Cheng-Fei Du
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, China
| | - Wei Lei
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Zi-Xiang Wu
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
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14
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Jesse CM, Raabe A, Ulrich CT. The Contralateral Approach to intra- and Extraforaminal Lumbar Disk Herniations: Surgical Technique and Review of Surgical Procedures. J Neurol Surg A Cent Eur Neurosurg 2021; 83:511-515. [PMID: 34897627 DOI: 10.1055/s-0041-1739221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Surgery for intra-/extraforaminal disk herniations (IEDH) is technically demanding due to the hidden location of the compressed nerve root section. Ipsilateral approaches (medial and lateral) are accompanied by extended resection of the facet joint and inadequate visualization of the pathology, especially at the L5-S1 level. METHODS We describe a microsurgical interlaminar contralateral approach (MICA) suitable for IEDH at the lumbosacral junction that can also be used at L4-L5 and L3-L4. CONCLUSION The MICA provides access and sufficient intraforaminal visualization for IEDH in the lumbosacral region without resection of stability-relevant structures or manipulation of the nerve root ganglion.
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Affiliation(s)
- Christopher Marvin Jesse
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Andreas Raabe
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Christian T Ulrich
- Department of Neurosurgery, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.,Department of Neurosurgery, Lindenhofspital, Bern, Switzerland
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15
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Shi Y, Xie YZ, Zhou Q, Yu Y, Fan XH. The biomechanical effect of the relevant segments after facet-disectomy in different diameters under posterior lumbar percutaneous endoscopes: a three-dimensional finite element analysis. J Orthop Surg Res 2021; 16:593. [PMID: 34649582 PMCID: PMC8515756 DOI: 10.1186/s13018-021-02733-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/16/2021] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE To evaluate the biomechanical influence after percutaneous endoscopic lumbar facetectomy in different diameters on segmental range of motion (ROM) and intradiscal pressure (IDP) of the relevant segments by establishing three dimensional finite element (FE) model. METHODS An intact L3-5 model was successfully constructed from the CT of a healthy volunteer as Model A (MA). The Model B (MB), Model C (MC) and Model D (MD) were obtained through facetectomy on L4 inferior facet in diameters 7.5 mm, 10 mm and 15 mm on MA for simulation. The ROM and IDP of L3/4 and L4/5 of four models were all compared in forward flexion, backward extension, left and right bending, left and right rotation. RESULTS Compared with MA, the ROM of L4/5 of MB, MC and MD all increased. MD changed more significantly than MB and MC in backward extension, right bending and right rotation. But that of MB and MC on L3/4 had no prominent change, while MD had a slight increase in backward extension. The IDP of MB and MC on L4/5 in six states was similar to MA, yet MD increased obviously in backward extension, right bending, left and right rotation. The IDP on L3/4 of MB and MC was resemble to MA in six conditions, nevertheless MD increased slightly only in backward extension. CONCLUSION Compared with the facetectomy in diameters 7.5 mm and 10 mm, the mechanical effect brought by facetectomy in diameter 15 mm on the operating segment changed more significantly, and had a corresponding effect on the adjacent segments.
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Affiliation(s)
- Yin Shi
- Hospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, Chengdu, 610072 Sichuan Province People’s Republic of China
| | - Yi-Zhou Xie
- Hospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, Chengdu, 610072 Sichuan Province People’s Republic of China
| | - Qun Zhou
- Chengdu University of Traditional Chinese Medicine, No. 1166 Liu-tai Avenue, Chengdu, 611137 Sichuan Province People’s Republic of China
| | - Yang Yu
- Hospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, Chengdu, 610072 Sichuan Province People’s Republic of China
| | - Xiao-Hong Fan
- Hospital of Chengdu University of Traditional Chinese Medicine, No. 39 Shi-er-qiao Road, Chengdu, 610072 Sichuan Province People’s Republic of China
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16
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Yee TJ, Strong MJ, Oppenlander ME. Commentary: Two-Level Minimally Invasive Lumbar Laminectomy and Foraminotomy: 2-Dimensional Operative Video. Oper Neurosurg (Hagerstown) 2021; 21:E238-E239. [PMID: 34131718 DOI: 10.1093/ons/opab200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/03/2021] [Indexed: 11/12/2022] Open
Affiliation(s)
- Timothy J Yee
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, USA
| | - Michael J Strong
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, USA
| | - Mark E Oppenlander
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, USA
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17
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Talukdar RG, Mukhopadhyay KK, Dhara S, Gupta S. Numerical analysis of the mechanical behaviour of intact and implanted lumbar functional spinal units: Effects of loading and boundary conditions. Proc Inst Mech Eng H 2021; 235:792-804. [PMID: 33832355 DOI: 10.1177/09544119211008343] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The objective of this study was to develop an improved finite element (FE) model of a lumbar functional spinal unit (FSU) and to subsequently analyse the deviations in load transfer owing to implantation. The effects of loading and boundary conditions on load transfer in intact and implanted FSUs and its relationship with the potential risk of vertebral fracture were investigated. The FE models of L1-L5 and L3-L4 FSUs, intact and implanted, were developed using patient-specific CT-scan dataset and segmentation of cortical and cancellous bone regions. The effect of submodelling technique, as compared to artificial boundary conditions, on the elastic behaviour of lumbar spine was examined. Applied forces and moments, corresponding to physiologic movements, were used as loading conditions. Results indicated that the loading and boundary conditions considerably affect stress-strain distributions within a FSU. This study, based on an improved FE model of a vertebra, highlights the importance of using the submodelling technique to adequately evaluate the mechanical behaviour of a FSU. In the intact FSU, strains of 200-400 µε were observed in the cancellous bone of vertebral body and pedicles. High equivalent stresses of 10-25 MPa and 1-5 MPa were generated around the pars interarticularis for cortical and cancellous regions, respectively. Implantation caused reductions of 85%-92% in the range of motion for all movements. Insertion of the intervertebral cage resulted in major deviations in load transfer across a FSU for all movements. The cancellous bone around cage experienced pronounced increase in stresses of 10-15 MPa, which indicated potential risk of failure initiation in the vertebra.
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Affiliation(s)
- Rahul Gautam Talukdar
- Advanced Technology and Development Centre, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
| | | | - Santanu Dhara
- School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
| | - Sanjay Gupta
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
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