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1.
PLoS One ; 17(8): e0272336, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35913954

RESUMO

Atlantoaxial instability (AAI) in dogs refers to abnormal motion at the C1-C2 articulation due to congenital or developmental anomalies. Surgical treatment options for AAI include dorsal and ventral stabilization techniques. Ventral stabilization techniques commonly utilize transarticular and vertebral body screws or pins. However, accurate screw insertion into the vertebrae of C1 and C2 is difficult because of the narrow safety corridors. This study included 10 mixed dogs, 1 Pomeranian, and 1 Shih-Tzu cadaver. All dogs weighed <10 kg. Each specimen was scanned using computed tomography (CT) from the head to the 7th cervical vertebrae. This study used 12 bone models and 6 patient-specific drill guides. Bone models were made using CT images and drill guides were created through a CAD (computer-aided design) program. A total of six cortical screws were used for each specimen. Two screws were placed at each of the C1, C2 cranial, and C2 caudal positions. Postoperative CT images of the cervical region were obtained. The degree of cortex breaching and angle and bicortical status of each screw was evaluated. The number of screws that did not penetrate the vertebral canal was higher in the guided group (33/36, 92%) than in the control group (20/36, 56%) (P = 0.003). The screw angles were more similar to the reference angle compared to the control group. The number of bicortically applied screws in the control group was 28/36 (78%) compared to 34/36 (94%) in the guided group. Differences between the preoperative plan and the length of the applied screw at the C1 and C2 caudal positions were determined by comparing the screw lengths in the guide group. The study results demonstrated that the use of a patient-specific 3D-printed drill guide for AAI ventral stabilization can improve the accuracy of the surgery. The use of rehearsal using bone models and a drilling guide may improve screw insertion accuracy.


Assuntos
Instabilidade Articular , Parafusos Pediculares , Fusão Vertebral , Animais , Parafusos Ósseos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Cães , Fixadores Internos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/cirurgia , Impressão Tridimensional , Fusão Vertebral/métodos
2.
Biomed Res Int ; 2022: 8273853, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845942

RESUMO

Biomechanical performance of longitudinal component in dynamic hybrid devices was evaluated to display the load-transfer effects of Dynesys cord spacer or Isobar damper-joint dynamic stabilizer on junctional problem based on various disc degenerations. The dynamic component was adapted at the mildly degenerative L3-L4 segment, and the static component was fixed at the moderately degenerative L4-L5 segment under a displacement-controlled mode for the finite element study. Furthermore, an intersegmental motion behavior was analyzed experimentally on the synthetic model under a load-controlled mode. Isobar or DTO hybrid fixator could reduce stress/motion at transition segment, but compensation was affected at the cephalic adjacent segment more than the caudal one. Within the trade-off region (as a motion-preserving balance between the transition and adjacent segments), the stiffness-related problem was reduced mostly in flexion by a flexible Dynesys cord. In contrast, Isobar damper afforded the effect of maximal allowable displacement (more than peak axial stiffness) to reduce stress within the pedicle and at facet joint. Pedicle-screw travel at transition level was related to the extent of disc degeneration in Isobar damper-joint (more than Dynesys cord spacer) attributing to the design effect of axial displacement and angular rotation under motion. In biomechanical characteristics relevant to clinical use, longitudinal cord/damper of dynamic hybrid lumbar fixators should be designed with less interface stress occurring at the screw-vertebral junction and facet joint to decrease pedicle screw loosening/breakage under various disc degenerations.


Assuntos
Degeneração do Disco Intervertebral , Parafusos Pediculares , Fusão Vertebral , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Fixadores Internos , Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Amplitude de Movimento Articular
3.
Iowa Orthop J ; 42(1): 249-254, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35821912

RESUMO

Background: As overall cancer survival continues to improve, the incidence of metastatic lesions to the bone continues to increase. The subsequent skeletal related events that can occur with osseous metastasis can be debilitating. Complete and impending pathologic femur fractures are common with patients often requiring operative fixation. However, the efficacy of an intramedullary nail construct, on providing stability, continue to be debated. Therefore, the purpose of this study was to utilize a synthetic femur model to determine 1) how proximal femur defect size and cortical breach impact femur load to failure (strength) and stiffness, and 2) and how the utilization of an IMN, in a prophylactic fashion, subsequently alters the overall strength and stiffness of the proximal femur. Methods: A total of 21 synthetic femur models were divided into four groups: 1) intact (no defect), 2) 2 cm defect, 3) 2.5 cm defect, and 4) 4 cm defect. An IMN was inserted in half of the femur specimens that had a defect present. This procedure was performed using standard antegrade technique. Specimens were mechanically tested in offset torsion. Force-displacement curves were utilized to determine each constructs load to failure and overall torsional stiffness. The ultimate load to failure and construct stiffness of the synthetic femurs with defects were compared to the intact synthetic femur, while the femurs with the placement of the IMN were directly compared to the synthetic femurs with matching defect size. Results: The size of the defect invertedly correlated with the load the failure and overall stiffness. There was no difference in load to failure or overall stiffness when comparing intact models with no defect and the 2 cm defect group (p=0.98, p=0.43). The 2.5 cm, and 4.5 cm defect groups demonstrated significant difference in both load to failure and overall stiffness when compared to intact models with results demonstrating 1313 N (95% CI: 874-1752 N; p<0.001) and 104 N/mm (95% CI: 98-110 N/mm; p=0.03) in the 2.5 cm defect models, and 512 N (95% CI: 390-634 N, p<0.001) and 21 N/mm (95% CI: 9-33 N/mm, p<0.001) in the models with a 4 cm defect. Compared to the groups with defects, the placement an IMN increased overall stiffness in the 2.5 cm defect group (125 N/mm; 95% CI:114-136 N/mm; p=0.003), but not load to failure (p=0.91). In the 4 cm defect group, there was a significant increase in load to failure (1067 N; 95% CI: 835-1300 N; p=0.002) and overall stiffness (57 N/mm; 95% CI:46-69 N/mm; p=0.001). Conclusion: Prophylactic IMN fixation significantly improved failure load and overall stiffness in the group with the largest cortical defects, but still demonstrated a failure loads less than 50% of the intact model. This investigation suggests that a cortical breach causes a loss of strength that is not completely restored by intramedullary fixation. Level of Evidence: II.


Assuntos
Fraturas do Fêmur , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/cirurgia , Fêmur/cirurgia , Humanos , Fixadores Internos/efeitos adversos , Extremidade Inferior
4.
Jt Dis Relat Surg ; 33(2): 294-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35852187

RESUMO

OBJECTIVES: The aim of this study was to simulate different entry points and investigate potential angulation errors of the intramedullary device and resulting changes in the distal femoral cut using a computer-aided design (CAD) approach. MATERIALS AND METHODS: We used a CAD approach to simulate various distal femoral entry points for intramedullary instrumentation. Simulations were performed on (i) a commercially available three-dimensional (3D) CAD model of a human femur (DigitalFemur) and (ii) a digital 3D model of an analogue large femur model produced using a coordinate measuring machine (FaroFemur). Divergent insertion points medial, lateral, anterior and posterior to the ideal position were simulated. Angulation deviations of the resulting positions of the intramedullary rod were measured and changes in the anatomical-mechanical axis angle were calculated. Differences between the two simulation models were quantified. RESULTS: The ideal entry point in the FaroFemur was 9.9 mm anterior and 4.3 mm medial to the apex of the intercondylar notch, and 9.2 mm anterior and 3.6 mm medial in the DigitalFemur. A medial entry point increased the angle between the anatomical femoral axis and the alignment rod in the FaroFemur and DigitalFemur (with 5 mm displacement 2.510° and 2.363°, respectively; with 10 mm displacement 3.239° and 3.283°, respectively). In contrast, a lateral entry point decreased the angle between the anatomical femoral axis and the alignment rod (with 5 mm displacement 2.267° and 2.262°, respectively; with 10 mm displacement 3.158° and 3.731°, respectively). An anterior entry point changed the angle between the anatomical femoral axis and the alignment rod towards extension (1.802° in the FaroFemur; 2.142° in the DigitalFemur), while a posterior entry point generated a deviation toward flexion (2.045° in the FaroFemur; 2.055° in the DigitalFemur). The mean difference between the two models was 0.108±0.121° with the highest difference for anterior displacement. CONCLUSION: Minor deviations of the entry point for intramedullary instrumentation during total knee arthroplasty can result in malalignment of several degrees.


Assuntos
Artroplastia do Joelho , Artroplastia do Joelho/métodos , Desenho Assistido por Computador , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Humanos , Fixadores Internos , Amplitude de Movimento Articular
5.
Acta Orthop ; 93: 547-553, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35700048

RESUMO

BACKGROUND AND PURPOSE: In younger patients with a femoral neck fracture (FNF), internal fixation is the recommended treatment regardless of displacement. Healing complications are often treated with arthroplasty. We determined the rate of conversion to arthroplasty up to 5 years after fixation of either undisplaced FNFs (uFNFs) or displaced FNFs (dFNFs). PATIENTS AND METHODS: The study was based on prospectively collected data from the Swedish Fracture Register (SFR) and the Swedish Arthroplasty Register (SAR). FNFs in patients aged < 60 treated with parallel pins/screws or sliding hip screws (SHS) registered in SFR 2012-2018 were cross-referenced with conversions to arthroplasty registered in SAR until 2019. The cumulative conversion and mortality rates were determined by Kaplan-Meier analyses and patient- and surgery-dependent risk factors for conversion by Cox regression analyses. RESULTS: We included 407 uFNFs and 389 dFNFs (median age 52, 59% men). The 1-year conversion rate was 3% (95% CI 1-5) for uFNFs and 9% (CI 6-12) for dFNFs. Corresponding results at 5 years were 8% (CI 5-11) and 25% (CI 20-30). Besides a displaced fracture, age 50-59 was associated with an increased rate of conversion in uFNFs. This older group also had a higher mortality rate, compared with patients aged < 50. There was no sex difference for mortality. INTERPRETATION: Adults aged under 60 with uFNFs and dFNFs face an 8-25% risk, respectively, of conversion to arthroplasty within 5 years after internal fixation. This is new and pertinent information for surgeons as well as patients.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Adulto , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Feminino , Fraturas do Colo Femoral/epidemiologia , Fraturas do Colo Femoral/etiologia , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Suécia/epidemiologia , Resultado do Tratamento
6.
Orthop Surg ; 14(5): 824-830, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35343060

RESUMO

The treatment of infected bone nonunion and bone defects is a considerable challenge in the orthopedics field. The standard clinical therapy methods include local free bone transplantation, vascularized bone graft, and the Ilizarov technique; the first two are controversial due to the iatrogenic self-injury. The Ilizarov bone transport technique has been widely used to treat infected bone nonunion and bone defects, and good clinical effect has been demonstrated. Yet, it brings many related complications, which exerts additional suffering to the patient. The best treatment is to combine bone defect rehabilitation with infection control, intramedullary nail fixation, appropriate time for bone grafts, beaded type scaffold slippage and new Taylor fixation, reducing the external fixation time and the incidence of complications, thereby reducing the occurrence of patients' physical and psychological problems. This review focuses on the induction, summary and analysis of the Ilizarov bone transport technique in the treatment of infected long bone nonunion with or without bone defects, providing new ideas and methods for orthopedic disease prevention and treatment by the Ilizarov technique, which is following the development direction of digital orthopedics.


Assuntos
Fraturas não Consolidadas , Técnica de Ilizarov , Fraturas da Tíbia , Transplante Ósseo , Fraturas não Consolidadas/cirurgia , Humanos , Fixadores Internos , Fraturas da Tíbia/cirurgia , Resultado do Tratamento
7.
Comput Math Methods Med ; 2022: 2008668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154357

RESUMO

Memory alloy patella claws for treating patella fractures have been used for more than 30 years with many desirable features including fast healing, quick recovery, and avoidance of top abrasion of Kirschner wires and other complications. However, there are many models and it is difficult to choose the accurate claw for the patient. In this study, a finite element model of the butterfly-shaped patellar claw made of shape memory alloy was established, its mechanical structure was analyzed, and its clinical application was monitored. We used Solidworks Simulation software for modeling and mainly analyzed the force of the compression ring of the butterfly-shaped patellar claw. Clinically, we chose a closed fresh patella fracture case. After finite element analysis, the maximum stress that the compression ring of the butterfly-shaped patellar claw can withstand is 568.1 MPa. In this range, it always has elastic deformation resistance. The butterfly-shaped patella claw is fixed on the patella and will not break when subjected to a maximum force of 150 N on the encircling arm, and at the same time, there will be no pressure failure due to plastic deformation. A total of 27 cases were clinically used for the assessment of the clinical efficacy of the newly designed butterfly-shaped patella claws. The average follow-up time was 15.5 months, and the average fracture healing time was 8-12 weeks. All patients can get out of bed with crutches within 2 to 3 days after surgery. Among them, there were 15 cases with excellent functional ratings, 10 cases with good ratings, 2 cases with acceptable ratings, and no cases with poor ratings. The designed butterfly-shaped patella claws can provide an effective method for the treatment of patella fractures.


Assuntos
Fixação Interna de Fraturas/instrumentação , Fixadores Internos , Fraturas Intra-Articulares/cirurgia , Patela/lesões , Patela/cirurgia , Adolescente , Adulto , Fenômenos Biomecânicos , Biologia Computacional , Simulação por Computador , Desenho Assistido por Computador/estatística & dados numéricos , Módulo de Elasticidade , Feminino , Análise de Elementos Finitos , Fixação Interna de Fraturas/estatística & dados numéricos , Humanos , Fixadores Internos/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Níquel , Desenho de Prótese , Ligas de Memória da Forma , Software , Estresse Mecânico , Resistência à Tração , Titânio , Resultado do Tratamento , Adulto Jovem
8.
Bone Joint J ; 104-B(2): 257-264, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35094579

RESUMO

AIMS: The aim of this study was to compare the clinical and radiological outcomes of patients with early-onset scoliosis (EOS), who had undergone spinal fusion after distraction-based spinal growth modulation using either traditional growing rods (TGRs) or magnetically controlled growing rods (MCGRs). METHODS: We undertook a retrospective review of skeletally mature patients who had undergone fusion for an EOS, which had been previously treated using either TGRs or MCGRs. Measured outcomes included sequential coronal T1 to S1 height and major curve (Cobb) angle on plain radiographs and any complications requiring unplanned surgery before final fusion. RESULTS: We reviewed 43 patients (63% female) with a mean age of 6.4 years (SD 2.6) at the index procedure, and 12.2 years (SD 2.2) at final fusion. Their mean follow-up was 8.1 years (SD 3.4). A total of 16 patients were treated with MCGRs and 27 with TGRs. The mean number of distractions was 7.5 in the MCGR group and ten in the TGR group (p = 0.471). The mean interval between distractions was 3.4 months in the MCGR group and 8.6 months in the TGR group (p < 0.001). The mean Cobb angle had improved by 25.1° in the MCGR group and 23.2° in TGR group (p = 0.664) at final follow-up. The mean coronal T1 to S1 height had increased by 16% in the MCGR group and 32.9% in TGR group (p = 0.001), although the mean T1 to S1 height achieved at final follow-up was similar in both. Unplanned operations were needed in 43.8% of the MCGR group and 51.2% of TGR group (p = 0.422). CONCLUSION: In this retrospective, single-centre review, there were no significant differences in major curve correction or gain in spinal height at fusion. Although the number of planned procedures were fewer in patients with MCGRs, the rates of implant-related complications needing unplanned revision surgery were similar in the two groups. Cite this article: Bone Joint J 2022;104-B(2):257-264.


Assuntos
Fixadores Internos , Imãs , Osteogênese por Distração/instrumentação , Escoliose/cirurgia , Fusão Vertebral , Adolescente , Idade de Início , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Osteogênese por Distração/métodos , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Resultado do Tratamento
9.
J Pediatr Orthop ; 42(3): e301-e308, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034037

RESUMO

BACKGROUND: Osteogenesis imperfecta is a collagen mutation-related disease characterized by bone fragility and other extraskeletal manifestations. Intramedullary fixation for deformity correction or fracture is the standard care. Elongating rods are designed to accommodate growth, with the aim of preventing additional operations and/or complications associated with nonelongating rods. Although elongating rods have been in use for many years, estimates of the clinical outcomes vary. We conducted a systematic review and meta-analysis to synthesize the literature on outcomes of elongating rods and nonelongating rods. Meta-analysis was used to compare the complication rates and reoperation rates. METHODS: We conducted the literature search, systematic review, and meta-analysis in accordance with Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. Comparative cohort studies and large case series detailing complication rates and reoperation rates of elongating and nonelongating rods were included. Random effect models were used to summarize the complication rates and reoperation rates of intramedullary rod procedures. RESULTS: A total of 397 studies were identified and 24 studies were included in the final cohort. Compared with rates from nonelongating rods, osteogenesis imperfecta Patients using elongating rods had a complication rate of 61% and a reoperation rate of 78%. Reoperation rates dropped with succeeding generations of elongating rods. Pooling data from 600 patients, we identified a 9% complication rate per rod per follow up year and 5% reoperation rate per rod and per follow up year in the cohort of elongating rod fixation. The Bailey-Dubow rod had the highest complication rate per rod per follow up year (12%), largely because of its T piece relate problems. The most popular fixator Fassier-Duval rod had a complication rate per rod per follow up year of 9%. About 68% of complications were mechanical-biological related. CONCLUSION: Pooling data from published literature demonstrates the advantage of elongating rods over nonelongating rods. However, as high as 9% complication rate per rod per follow up year was associated with elongating fixation. Notably, most complications are both mechanical and biological related. LEVEL OF EVIDENCE: Level III.


Assuntos
Fixação Intramedular de Fraturas , Osteogênese Imperfeita , Fixação Intramedular de Fraturas/efeitos adversos , Humanos , Fixadores Internos , Extremidade Inferior , Osteogênese Imperfeita/cirurgia , Reoperação
11.
J Pediatr Orthop B ; 31(3): 224-231, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34050119

RESUMO

This study compares clinical, radiographic and patient-reported outcomes among telescoping and traditional screws for the treatment of slipped capital femoral epiphysis (SCFE). We hypothesized that telescoping screws would prevent slip progression and result in preserved femoral neck growth and improved patient-reported outcomes. Traditional screws were compared to telescoping screws in a 2:1 matched cohort based on age at initial surgery, length of radiographic follow-up and whether or not the hip was pinned prophylactically or as a treatment for SCFE. Neck length and telescoping screw length were measured. The patient-reported outcomes were obtained at routine clinic visits. Total 42 hips were included with a mean follow-up of 24.5 ± 3.3 months. No patients developed avascular necrosis, chondrolysis or needed revision surgical procedures. Telescoping screws increased in length for the entire cohort by a mean of 6.0 ± 4.3 mm. Neck length change was not different in SCFE hips when treated with traditional screws vs. telescoping screws (P = 0.527). However, there was a difference in neck length change between the two groups when comparing prophylactically treated hips (P = 0.001). There were no significant differences in patient-reported outcomes among hips treated with telescoping screws compared to traditional screws. Traditional and telescoping screws are both effective for the treatment of SCFE. Telescoping screws have an advantage when prophylactically treating hips that are at risk of slipping as they don't lead to the coxa breva that is seen with traditional screws. However, both treatment methods had similar patient-reported outcomes.


Assuntos
Escorregamento das Epífises Proximais do Fêmur , Parafusos Ósseos , Colo do Fêmur , Humanos , Fixadores Internos , Medidas de Resultados Relatados pelo Paciente , Escorregamento das Epífises Proximais do Fêmur/diagnóstico por imagem , Escorregamento das Epífises Proximais do Fêmur/cirurgia
12.
J Neurosurg Spine ; 36(1): 62-70, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34479187

RESUMO

OBJECTIVE: In corrective spinal surgery for adult spinal deformity (ASD), the focus has been on achieving optimal spinopelvic alignment. However, the correction of coronal spinal alignment is equally important. The conventional intraoperative measurement methods currently used for coronal alignment are not ideal. Here, the authors have developed a new intraoperative coronal alignment measurement technique using a navigational tool for a 3D spinal rod bending system (CAMNBS). The purpose of this study was to test the feasibility of using the CAMNBS for coronal spinal alignment and to evaluate its usefulness in corrective spinal surgery for ASD. METHODS: In this retrospective cohort study, patients with degenerative lumbar kyphoscoliosis, a Cobb angle ≥ 20°, and lumbar lordosis ≤ 20° who had undergone corrective surgery (n = 67) were included. The pelvic teardrops on both sides, the S1 spinous process, the central point of the apex, a point on the 30-mm cranial (or caudal) side of the apex, and the central point of the upper instrumented vertebra (UIV) and C7 vertebra were registered using the CAMNBS. The positional information of all registered points was displayed as 2D figures on a monitor. Deviation of the UIV plumb line from the central sacral vertical line (UIV-CSVL) and deviation of the C7 plumb line from the CSVL (C7-CSVL) were measured using the 2D figures. Nineteen patients evaluated using the CAMNBS (BS group) were compared with 48 patients evaluated using conventional intraoperative radiography (XR group). The UIV-CSVL measured intraoperatively using the CAMNBS was compared with that measured using postoperative radiography. The prevalence of postoperative coronal malalignment (CM) and the absolute value of postoperative C7-CSVL were compared between the groups on radiographs obtained in the standing position within 4 weeks after surgery. Postoperative CM was defined as the absolute value of C7-CSVL ≥ 30 mm. Further, the measurement time and amount of radiation exposure were measured. RESULTS: No significant differences in demographic, sagittal, and coronal parameters were observed between the two groups. UIV-CSVL was 2.3 ± 9.5 mm with the CAMNBS and 1.8 ± 16.6 mm with the radiographs, showing no significant difference between the two methods (p = 0.92). The prevalence of CM was 2/19 (10.5%) in the BS group and 18/48 (37.5%) in the XR group, and absolute values of C7-CSVL were 15.2 ± 13.1 mm in the BS group and 25.0 ± 18.0 mm in the XR group, showing statistically significant differences in both comparisons (p = 0.04 and 0.03, respectively). The CAMNBS method required 3.5 ± 0.9 minutes, while the conventional radiograph method required 13.3 ± 1.5 minutes; radiation exposure was 2.1 ± 1.1 mGy in the BS group and 2.9 ± 0.6 mGy in the XR group. Statistically significant differences were demonstrated in both comparisons (p = 0.0002 and 0.03, respectively). CONCLUSIONS: From this study, it was evident that the CAMNBS did not increase postoperative CM compared with that seen using the conventional radiographic method, and hence can be used in clinical practice.


Assuntos
Cuidados Intraoperatórios/métodos , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Curvaturas da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Sistemas de Navegação Cirúrgica , Idoso , Estudos de Viabilidade , Feminino , Humanos , Fixadores Internos , Cuidados Intraoperatórios/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fusão Vertebral/instrumentação , Resultado do Tratamento
13.
Comput Methods Biomech Biomed Engin ; 25(5): 536-542, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34392764

RESUMO

The objective was to compare L4/5 range of motions of fusion constructs using anchored cages. Twelve human cadaveric spine were tested in intact condition, and divided into TLIF and PLIF groups. Testing consisted in applying pure moments in flexion-extension, lateral bending and axial rotation. The computation of intersegmental motion was assessed using 3 D biplanar radiographs. In TLIF group, the addition of contralateral transfacet decreased flexion-extension motion (39%; p = 0.036) but without difference with the ipsilateral pedicle screw construction (53%; p = 0.2). In PLIF group, the addition of interspinous anchor reduced flexion-extension motion (12%; p = 0.036) but without difference with the bilateral pedicle screw construction (17%; p = 0.8).


Assuntos
Parafusos Pediculares , Fusão Vertebral , Fenômenos Biomecânicos , Cadáver , Humanos , Fixadores Internos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Amplitude de Movimento Articular , Rotação , Raios X
14.
J Neurosurg Spine ; 36(1): 86-92, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34507297

RESUMO

OBJECTIVE: Pelvic fixation enhances long constructs during deformity surgery. Subsequent loosening of iliac screws and pain at the pelvis occur in as many as 29% of patients. Concomitant sacroiliac (SI) fusion may prevent potential pain and failure. The objective of this study was to describe a novel surgical technique and a single institution's experience using bilateral SI fusion during adult deformity surgery with S2-alar-iliac (S2AI) screws and triangular titanium rods (TTRs) placed with navigation. METHODS: The authors reviewed open SI joint fusions with TTR performed between August 2019 and March 2020. All patients underwent lumbosacral fusion through a midline approach and bilateral S2AI pelvic fixation in the caudal teardrop, followed by TTR placement just proximal and cephalad to the S2AI screws using intraoperative CT imaging guidance. RESULTS: Twenty-one patients were identified who received 42 TTRs, ranging in size from 7.0 × 65 mm to 7.0 × 90 mm. Three TTRs (7%) were malpositioned intraoperatively, and each was successfully repositioned during index surgery without negative sequelae. All breaches occurred in a medial and cephalad direction into the pelvis. Incremental operative time for adding TTR averaged 8 minutes and 33 seconds per implant. CONCLUSIONS: Image-guided open SI joint fusion with TTR during lumbosacral fusion is technically feasible. The bony corridor for implant placement is narrower cephalad, and implants tend to deviate medially into the pelvis. Detection of malpositioned implant is aided with intraoperative CT, but this can be salvaged. A prospective randomized clinical trial is underway that will better inform the impact of this technique on patient outcomes.


Assuntos
Fixadores Internos , Articulação Sacroilíaca/cirurgia , Curvaturas da Coluna Vertebral/cirurgia , Fusão Vertebral/instrumentação , Titânio , Adulto , Idoso , Estudos de Coortes , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Fusão Vertebral/métodos
15.
Clin Orthop Relat Res ; 480(1): 163-188, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34324459

RESUMO

BACKGROUND: A major complication of lateral lumbar interbody fusion (LLIF) is cage subsidence, which may lead to clinical problems, including loss of disc height correction, altered spinal alignment, recurrent pain, and vertebral body fracture. A thorough review of the current knowledge about the risk factors for the two types of cage subsidence after LLIF-intraoperative endplate injury and late-onset cage subsidence-could bring attention to well-established risk factors for clinical consideration while identifying any incompletely characterized factors that require further research to clarify. QUESTIONS/PURPOSES: We performed a systematic review to answer the following questions: (1) Are bone quality and surrogates for bone quality, such as patient age and sex, associated with an increased likelihood of cage subsidence? (2) Are implant-related factors associated with an increased likelihood of cage subsidence? METHODS: Two independent reviewers comprehensively searched Medline, Embase, Cochrane Library, PubMed, and Web of Science from 1997 to 2020 to identify all potential risk factors for cage subsidence after LLIF. Discrepancies were settled through discussion during full-text screening. Search terms included "lateral" AND "interbody fusion" AND "subsidence" OR "settling" OR "endplate injury" OR "endplate violation" WITHOUT "cervical" OR "transforaminal" OR "biomechanical." Eligible studies were retrospective or prospective comparative studies, randomized controlled trials, and case series with sample sizes of 10 patients or more reporting risk factors for cage subsidence or endplate injury after LLIF. Studies that involved cervical interbody fusions and biomechanical and cadaveric experiments were excluded. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the studies' quality of evidence. The initial database review found 400 articles. Thirty-four articles with moderate- to very-low-quality evidence met the inclusion criteria for analysis. A total of 3233 patients (58% [1860] of whom were female) were included in this review. Two types of cage subsidence were reviewed: late-onset cage subsidence, which occurs gradually postoperatively, and intraoperative endplate injury, which is derived from iatrogenic endplate violation during endplate preparation or cage insertion. Among 20 studies with moderate quality of evidence according to the GRADE criteria, eight studies reported risk factors for cage subsidence related to bone mineral density and its surrogates and 12 studies focused on risk factors regarding implant factors, including cage dimension, cage material, construct length, and supplementary instrumentation. RESULTS: Patients with a dual x-ray absorptiometry T-score of -1.0 or less, age older than 65 years, and female sex were considered to have a high risk of both types of cage subsidence. Regarding cage size, cage width ≥ 22 mm helped to avoid late-onset cage subsidence, and cage height ≤ 11 mm was recommended by some studies to avoid intraoperative endplate injuries. Studies recommended that multilevel LLIF should be conducted with extra caution because of a high risk of losing the effect of indirect decompression. Studies found that standalone LLIF might be sufficient for patients without osteoporosis or obesity, and supplementary instrumentation should be considered to maintain the postoperative disc height and prevent subsidence progression in patients with multiple risk factors. The effect of the bone graft, cage material, endplate condition, and supplementary instrumentation on cage subsidence remained vague or controversial. CONCLUSION: Patients with poor bone density, patients who are older than 65 years, and female patients should be counseled about their high risk of developing cage subsidence. Surgeons should avoid narrow cages when performing LLIF to minimize the risk of late-onset cage subsidence, while being cautious of an aggressive attempt to restore disc height with a tall cage as it may lead to intraoperative endplate injury. For multilevel constructs, direct decompression approaches, such as posterior and transforaminal LIF, should be considered before LLIF, since the effect of indirect decompression may be difficult to maintain in multilevel LLIF because of high risks of cage subsidence. The effect of the cage material and supplementary instrumentation require stronger evidence from prospectively designed studies with larger sample size that randomly assign patients to polyetheretherketone (PEEK) or titanium cages and different fixation types. Future research on intraoperative endplate injuries should focus on the specific timing of when endplate violation occurs with the help of intraoperative imaging so that attempts can be made to minimize its occurrence. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Fixadores Internos , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/etiologia , Fusão Vertebral/métodos , Fatores Etários , Densidade Óssea , Humanos , Fatores de Risco , Fatores Sexuais , Fusão Vertebral/instrumentação
16.
World Neurosurg ; 157: 56-63, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648988

RESUMO

OBJECTIVE: This study aimed to demonstrate the utility of power tools and intraoperative neuromonitoring of percutaneous pedicle screw (PPS) insertion (so-called PPS monitoring) by SINGLE-position surgery (SPS) after lateral lumbar interbody fusion. METHODS: A retrospective analysis of medical records from a single center was performed to identify patients who underwent SPS for lateral lumbar interbody fusion and posterior fixation using PPS during intraoperative computed tomography navigation from 2020 to 2021. We investigated the PPS insertion time and screw positional accuracy of patients who underwent SPS involving power tools and PPS monitoring during this period. In this technical note, we report on this surgical technique. RESULTS: Twenty-four patients (mean age 72.0 ± 8.5 years, range 53-81 years) were included in this study. There were no intraoperative complications in all cases. Posterior fixation using PPS was added in all cases, and a total of 106 PPSs were inserted. It took an average of 6.2 ± 2.4 seconds to insert the PPS from the PPS insertion point to the end using a power tool and PPS monitoring. Moreover, there were no cases of pedicle breaches. CONCLUSIONS: Similar to previous reports related to power tools in the prone position, the lateral decubitus SPS technique can also use power tools to save PPS insertion time. Furthermore, we suggest that the use of PPS monitoring may prevent erroneous PPS insertions by using intraoperative computed tomography navigation in advance.


Assuntos
Monitorização Neurofisiológica Intraoperatória , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Parafusos Pediculares , Instrumentos Cirúrgicos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente , Estudos Retrospectivos , Fusão Vertebral , Tomografia Computadorizada por Raios X , Resultado do Tratamento
17.
J Craniofac Surg ; 33(1): 187-191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34643602

RESUMO

BACKGROUND: The purpose of this study was to develop a methodology for quantifying linear forces of distraction osteogenesis, and thereafter apply this methodology to measure and compare distraction force magnitudes between cranial vault distraction osteogenesis (CVDO) and mandibular distraction osteogenesis (MDO). METHODS: Patients undergoing CVDO or MDO as inpatients had distraction forces acquired with a digital torque-measuring screwdriver. Torque measurements were then converted into linear distraction force values, which were then compared across distraction types and protocols with appropriate statistics. RESULTS: CVDO was performed on 7 patients (41.2%), and MDO was performed on 10 patients (58.8%). Across the entire cohort, the average maximum force per activation was 27.0 N, and the average elastic force was 10.7 N. Maximum force (CVDO: 52.9 N versus MDO: 12.9 N; P < 0.001) and elastic force (CVDO: 22.0 N versus MDO: 4.5 N; P < 0.001) were significantly higher in patients undergoing CVDO than MDO. Multivariate regression demonstrated that maximum activation force was significantly associated with sequential days of distraction (B= + 1.1 N/day; P < 0.001), distraction rate (B= + 8.9 N/mm/day; P = 0.016), distractor hardware failure (B= + 10.3 N if failure; P = 0.004), and distraction type (B= + 41.4 N if CVDO; P < 0.001). CONCLUSIONS: Cranial vault distraction requires significantly more linear distraction force than mandibular distraction. Maximum forces increase with each day of distraction, as well as with increased distraction rates. Linear distraction force methodology from this study may provide the foundation for future development of optimized procedure-specific or patient-specific distraction protocols.


Assuntos
Osteogênese por Distração , Humanos , Fixadores Internos , Mandíbula/cirurgia , Estudos Retrospectivos , Crânio/cirurgia , Torque , Resultado do Tratamento
18.
Turk Neurosurg ; 32(2): 292-297, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34936079

RESUMO

AIM: To evaluate whether adding an extra anchoring point to the construct by passing the crosslink through a hole in the spinous process (trans-spinous crosslink technique), may prevent screw loosening by increasing the pull-out strength. MATERIAL AND METHODS: Twenty-four fresh-frozen single lumbar sheep vertebrae were instrumented with pedicle screws bilaterally, and they are connected to each other with a crosslink. All vertebrae were assigned randomly to either the experiment (trans-spinous crosslink) group or the control group. In the experiment group, the crosslink was passed through a hole within the spinous process. In the control group, the posterior part of the hole was removed. The pull-out force of the construct was determined using a mechanical testing machine. RESULTS: The mean pull-out forces of the experiment group and the control group were 1949 ± 361.55 N and 1338.57 ± 220.26 N, respectively. The pull-out force of the experiment group was significantly higher than those of the control group with 99.9% confidence (p < 0.001). CONCLUSION: The pedicle screws rigidly anchor the internal fixation devices to the vertebral colon. In classical construct design, pedicle screws share the load. Adding extra anchoring points decreases screw share and may prevent construct pull-out. This study shows that the trans-spinous crosslink can serve as an anchoring point and increases the construct pull-out strength.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Animais , Fenômenos Biomecânicos , Fixadores Internos , Vértebras Lombares/cirurgia , Ovinos , Fusão Vertebral/métodos
19.
J Orthop Surg Res ; 16(1): 715, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34906168

RESUMO

BACKGROUND: How to perform minimally invasive surgery for Tile C pelvic fracture is a major problem in clinical practice. We performed minimally invasive surgery for Tile C pelvic fracture using anterior ring internal fixator systems combined with sacroiliac screw fixation. OBJECTIVE: To investigate the advantages and efficacy of anterior ring internal fixator systems combined with sacroiliac screw fixation in the treatment of Tile C pelvic fracture. METHODS: From May 2017 to May 2020, 27 patients with Tile C pelvic fracture who underwent anterior ring internal fixator system combined with sacroiliac screw fixation (group A) and 21 patients with Tile C pelvic fracture who underwent plate-screw system combined with sacroiliac screw fixation (group B) were retrospectively analyzed. RESULTS: All 48 patients were followed up for more than 12 months, all fractures healed within 3-6 months. The operative time, intraoperative bleeding volume, blood transfusion volume, incision length, hospital stay, complication rate and Majeed score were 63.5 ± 10.7 min, 48.3 ± 27.9 ml, 0 ml, 4.5 ± 0.8 cm, 10.2 ± 2.7 d, 3.7% and 89.7 ± 4.6 points, respectively, in group A and 114.8 ± 19.1 min, 375 ± 315.8 ml, 266.7 ± 326.6 ml, 9.2 ± 3.9 cm, 20.9 ± 5.7 d, 23.8% and 88.7 ± 4.9 points, respectively, in group B. Combined excellent and good rates of the Matta evaluation and Majeed score were 100% in both groups. There were no significant differences in the Matta evaluation or Majeed score between the two groups (both P > 0.05), whereas the operative time, intraoperative bleeding volume, blood transfusion volume, incision length and hospital stay were significantly less in group A (all P < 0.05). CONCLUSION: An anterior ring internal fixator system combined with sacroiliac screw fixation can effectively treat Tile C pelvic fracture, and has advantages, including minimal invasiveness, simple operation, short operative time, safe and reliable features, fewer complications, short hospital stay and a good curative effect.


Assuntos
Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Fixadores Internos , Ossos Pélvicos/lesões , Adulto , Idoso , Feminino , Fixação Interna de Fraturas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
20.
Acta Chir Orthop Traumatol Cech ; 88(5): 333-338, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34738891

RESUMO

PURPOSE OF THE STUDY Vertically unstable transforaminal sacral fractures can be stabilized with several types of transiliac internal fixators (TIFI): the classical one (TIFI-C), the supraacetabular one (TIFI-A) and by dual application of TIFI (DTIFI). MATERIAL AND METHODS Pelvic models made of solid foam (Sawbones 1301) were used in the study. Mechanical loading tests were performed in order to assess the stiffness of the studied pelvic structures. The stiffness of the intact model was approximated as the slope of load/displacement curve. Then vertically unstable right-sided linear transforaminal fracture was created and subsequently fixed by TIFI-C, TIFI-A and DTIFI (each fixator for a separate model). The fixation techniques were compared based on the ratio between the stiffness of the treated and of the intact pelvis. Motion of the posterior pelvic structures and their deformations were measured using a photogrammetric system with four synchronous cameras. Loads applied at the base of sacrum and sacral base displacements were recorded by the testing device and used to assess the stiffness of the model structure. A dedicated load cell and a monoaxial extensometer were utilised. Every measurement was repeated at least 10 times. Obtained data were analysed by one way ANOVA test with post hoc comparison by Tukey HSD test. RESULTS Mean stiffness ratio (±1SD) of pelvic structure was 0.638 ± 0.005 for TIFI-C, 0.722 ± 0.014 for TIFI-A and 0.720 ± 0.008 for DTIFI. Dual transiliac internal fixation and supraacetabular fixation were superior to the classical one (p < 0.0001), but DTIFI and TIFI-A stiffness ratios were statistically equivalent (p = 0.9112). CONCLUSIONS Results of the mechanical analysis using pelvic models indicate that for linear vertical transforaminal sacral fracture without comminuted zone, an application of either TIFI-A or DTIFI provides significantly higher stiffness of the lateral pelvic segment than application of TIFI-C. Key words: transforaminal sacral fracture, transiliac internal fixator, dual TIFI, stability, biomechanics, digital image correlation.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Fenômenos Biomecânicos , Parafusos Ósseos , Fixação Interna de Fraturas , Humanos , Fixadores Internos , Testes Mecânicos , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/cirurgia , Pelve , Sacro/cirurgia
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