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1.
BMC Musculoskelet Disord ; 25(1): 157, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373917

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) rupture is a common orthopedic injury, occurring in roughly 68.6 per 100,000 persons annually, with the primary treatment option being ACL reconstruction. However, debate remains about the appropriate graft type for restoring the native biomechanical properties of the knee. Furthermore, plastic graft elongation may promote increased knee laxity and instability without rupture. This study aims to investigate the plastic properties of common ACL-R graft options. METHODS: Patellar tendon (PT), hamstring tendon (HT), and quadriceps tendon (QT) grafts were harvested from 11 cadaveric knees (6 male and 5 female) with a mean age of 71(range 55-81). All grafts were mechanically tested under uniaxial tension until failure to determine each graft's elastic and plastic biomechanical properties. RESULTS: Mechanically, the QT graft was the weakest, exhibiting the lowest failure force and the lowest failure stress (QT < HT, p = 0.032). The PT was the stiffest of the grafts, having a significantly higher stiffness (PT > QT, p = 0.0002) and Young's modulus (PT > QT, p = 0.001; PT > HT, p = 0.041). The HT graft had the highest plastic elongation at 4.01 ± 1.32 mm (HT > PT, p = 0.002). The post-yield behavior of the HT tendon shows increased energy storage capabilities with the highest plastic energy storage (HT > QT, p = 0.012) and the highest toughness (HT > QT, p = 0.032). CONCLUSION: Our study agrees with prior studies indicating that the failure load of all grafts is above the requirements for everyday activities. However, grafts may be susceptible to yielding before failure during daily activities. This may result in the eventual loss of functionality for the neo-ACL, resulting in increased knee laxity and instability.


Assuntos
Lesões do Ligamento Cruzado Anterior , Ligamento Patelar , Masculino , Humanos , Feminino , Idoso , Ligamento Cruzado Anterior/cirurgia , Autoenxertos/cirurgia , Transplante Autólogo , Articulação do Joelho/cirurgia , Ligamento Patelar/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia
2.
BMC Musculoskelet Disord ; 24(1): 105, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750786

RESUMO

BACKGROUND: The current understanding of glenohumeral joint stability is defined by active restrictions and passive stabilizers including naturally-occurring negative intraarticular pressure. Cadaveric specimens have been used to evaluate the role of intraarticular pressure on joint stability, although, while the shoulder's negative intraarticular pressure is universally acknowledged, it has been inconsistently accounted for. HYPOTHESIS: During continuous, passive humeral abduction, releasing the native intraarticular pressure increases joint translation, and restoring this pressure decreases joint translations. STUDY DESIGN: Descriptive Laboratory Study. METHODS: A validated shoulder testing system was used to passively abduct the humerus in the scapular plane and measure joint translations for seven (n = 7) cadaveric specimens. The pressure within the glenohumeral joint was measured via a 25-gauge needle during passive abduction of the arm, which was released and subsequently restored. During motion, the rotator cuff muscles were loaded using stepper motors in a force feedback loop and electromagnetic sensors were used to continuously measure the position of the humerus and scapula. Joint translation was defined according to the instant center of rotation of the glenohumeral head according to the recommendations by the International Society of Biomechanics. RESULTS: Area under the translation versus abduction angle curve suggests that releasing the pressure within the capsule results in significantly less posterior translation of the glenohumeral head as compared to intact (85-90˚, p < 0.05). Posterior and superior translations were reduced after 70˚ of abduction when the pressure within the joint was restored. CONCLUSION: With our testing system employing a smooth continuous passive motion, we were able to show that releasing intraarticular pressure does not have a major effect on the path of humeral head motion during glenohumeral abduction. However, both violating the capsule and restoring intraarticular pressure after releasing alter glenohumeral translations. Future studies should study the effect of simultaneous external rotation and abduction on the relationship between joint motion and IAP, especially in higher degrees of abduction. CLINICAL RELEVANCE: Thoroughly simulating the glenohumeral joint environment in the cadaveric setting may strengthen the conclusions that can be translated from this setting to the clinic.


Assuntos
Articulação do Ombro , Ombro , Humanos , Fenômenos Biomecânicos , Articulação do Ombro/fisiologia , Cabeça do Úmero , Amplitude de Movimento Articular/fisiologia , Cadáver
3.
Knee Surg Sports Traumatol Arthrosc ; 25(2): 454-458, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28028568

RESUMO

PURPOSE: The purpose of this study was to evaluate and describe the clinical results and outcomes of a novel method for all-inside suture repair of medial meniscus ramp lesions through posteromedial and posterolateral transseptal portals during anterior cruciate ligament (ACL) reconstruction. Further, this investigation compared the posterolateral view to the notch view for diagnosis and repair. METHODS: Between 2011 and 2014, 166 patients had ramp lesions concomitantly with ACL injury; 128 patients (107 men and 21 women) were enrolled in the study after qualification. All patients underwent repair of the posterior horn ramp lesion of the medial meniscus, using a suture hook device with PDS No. 1 through a posteromedial portal while viewing from the posterolateral transseptal portal during ACL reconstruction, with a minimum of a 2-year follow-up. RESULTS: Patients were followed up for a minimum of 2 years (range 24-47 months). Their average Lysholm score increased from 61.7 ± 3.2 preoperatively to 87.8 ± 3.9 at last follow-up (p < 0.001). Moreover, their average IKDC scores also improved from 53.6 ± 2.1 (pre-op) to 82.1 ± 3.5 (at last follow-up) (p < 0.001). The peroneal nerve and the popliteal neurovascular bundle were not damaged in any of the patients. CONCLUSION: This study provides evidence that the posterolateral transseptal technique protects neurovascular structures. This technique may be used safely and easily for repair of the posterior horn ramp lesion of the medial meniscus during ACL reconstruction. LEVEL OF EVIDENCE: IV.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/métodos , Artroscopia/métodos , Meniscos Tibiais/cirurgia , Avaliação de Resultados em Cuidados de Saúde , Técnicas de Sutura , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
4.
Front Bioeng Biotechnol ; 12: 1384280, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770275

RESUMO

Introduction: The trabecular network is perceived as a collection of interconnected plate- (P) and rod-like (R) elements. Previous research has highlighted how these elements and their connectivity influence the mechanical properties of bone, yet further work is required to elucidate better the deeply interconnected nature of the trabecular network with distinct element formations conducting forces per their mechanical boundary conditions. Within this network, forces act through elements: a rod or plate with force applied to one end will transmit this force to a component connected to the other end, defining the boundary conditions for the loading of each element. To that end, this study has two aims: First, to investigate the connectivity of individually segmented elements of trabecular bone with respect to their local boundary conditions as defined by the surrounding trabecular network and linking them directly to the bone's overall mechanical response during loading using a mathematical graph model of the plate and rod (PR) Network. Second, we use this model to quantify side artifacts, a known artifact when testing an excised specimen of trabecular bone, where vertical trabeculae lose their load-bearing capacity due to a loss of connectivity, ultimately resulting in a change of the trabecular network topology. Resuts: Connected elements derived from our model predicted apparent elastic modulus by fitting a linear regression (R 2 = 0.81). In comparison, prediction using conventional bone volume fraction results in a lower accuracy (R 2 = 0.72), demonstrating the ability of the PR Network to estimate compressive elastic modulus independent of specimen size or loading boundary condition. Discussion: PR Network models are a novel approach to describing connectivity within the trabecular network and incorporating mechanical boundary conditions within the morphological analysis, thus enabling the study of intrinsic material properties of trabecular bone. Ultimately, PR Network models may be an early predictor or provide further insights into osteo-degenerative diseases.

5.
Spine J ; 24(9): 1759-1772, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38704096

RESUMO

BACKGROUND CONTEXT: The opioid epidemic is a public health crisis affecting spine care and pain management. Medical marijuana is a potential nonopioid analgesic yet to be studied in the surgical setting since its effects on bone healing are not fully understood. Studies have demonstrated analgesic and potentially osteoinductive properties of cannabinoids with endocannabinoid receptor expression in bone tissue. PURPOSE: We hypothesize that tetrahydrocannabinol (THC) and cannabidiol (CBD) will not decrease bone healing in spinal fusion. STUDY DESIGN: Seventy-eight adult Sprague-Dawley rats were used for this study. Utilizing allogenic bone grafts (6 donor rats), posterolateral inter-transverse lumbar fusion at the L4-L5 level was performed. The animals were equally divided into four treatment groups, each receiving 0.1 ml intraperitoneal injections weekly as follows: placebo (saline), 5 mg/kg THC, 5 mg/kg CBD, and a combination of 5 mg/kg THC and 5mg/kg CBD (Combo). METHODS: Callus tissue was harvested 2- and 8-weeks postsurgery for qPCR assessment to quantify changes in the expression of osteogenic genes. Manual palpation was done to assess the strength of the L4-L5 arthrodesis on all rats. µCT image-based callus analysis and histology were performed. One-way ANOVA followed by post hoc comparisons was performed. RESULTS: µCT demonstrated no significant differences. Treatment groups had slightly increased bone volume and density compared to control. qPCR at 2 weeks indicated downregulated RANKL/OPG ratios skewing towards osteogenesis in the CBD group, with the THC and CBD+THC groups demonstrating a downward trend (p>.05). ALPL, BMP4, and SOST were significantly higher in the CBD group, with CTNNB1 and RUNX2 also showing an upregulating trend. The CBD group showed elevation in Col1A1 and MMP13. Data at eight weeks showed ALPL, RUNX2, BMP4, and SOST were downregulated for all treatment groups. In the CBD+THC group, RANK, RANKL, and OPG were downregulated. OPG downregulation reached significance for the THC and CBD+THC group compared to saline. Interestingly, the RANKL/OPG ratio showed upregulation in the CBD and CBD+THC groups. RANKL showed upregulation in the CBD group. At 2 and 8 weeks, the CBD treatment group showed superior histological progression, increasing between time points. CONCLUSION: This study demonstrates that CBD and THC have no adverse effect on bone healing and the rate of spinal fusion in rats. Osteogenic factors were upregulated in the CBD-treated groups at 2 weeks, which indicates a potential for bone regeneration. In this group, compared to control, the RANKL/OPG ratio at the early healing phase demonstrates the inhibition of osteoclast differentiation, enhancing bone formation. Interestingly, it shows promoted osteoclast differentiation at the later healing phase, enhancing bone remodeling. This aligns with the physiological expectation of a lower ratio in the early phases and a higher ratio in the later remodeling phases. CLINICAL SIGNIFICANCE: CBD and THC showed no inhibitory effects on bone healing in a spinal fusion model. Moreover, histologic and gene expression analysis demonstrated that CBD may, in fact, enhance bone healing. Further research is needed to confirm the safe usage of THC and CBD in the postoperative setting following spinal fusions.


Assuntos
Dronabinol , Vértebras Lombares , Ratos Sprague-Dawley , Fusão Vertebral , Animais , Ratos , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Dronabinol/farmacologia , Dronabinol/administração & dosagem , Canabidiol/farmacologia , Canabidiol/administração & dosagem , Canabinoides/farmacologia , Masculino , Transplante Ósseo/métodos
6.
Arthrosc Sports Med Rehabil ; 6(1): 100815, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38149088

RESUMO

Purpose: This study aims to determine the overall incidence of venous thromboembolism (VTE) following shoulder arthroscopy and to define potential risk factors associated with its development that may help define guidelines for the use of thromboprophylaxis. Methods: A systematic review was performed using PubMed, Embase, Web of Science, CINAHL, and Cochrane databases per PRISMA guidelines. The search terms consisted of variations of "Venous Thromboembolism" and "Shoulder Arthroscopy." Information regarding arthroscopy indication, risk factors, outcomes, and patient demographics was recorded and analyzed, and pooled odds ratios were reported for each variable. Results: Six hundred eighty-five articles were identified in the initial search, and 35 articles reported DVT, PE, or VTE incidence following shoulder arthroscopy. Seventeen nonoverlapping articles with a unique patient population incidence rates. Four articles were then used for subgroup meta-analysis. The incidence rate of VTE was 0.24%, ranging from 0.01% to 5.7%. BMI >30 (OR = 1.46; 95% CI = [1.22, 1.74]; I2 = 0%) and hypertension (OR = 1.64; 95% CI = [1.03, 2.6]; I2 = 75%) were significant risk factors (P < .05) for developing VTE following shoulder arthroscopy. Diabetes (OR = 1.2; 95% CI = [0.97, 1.48]; I2 = 0%), insulin-dependent diabetes (OR = 5.58; 95% CI = [0.12, 260.19]; I2 = 85%), smoking (OR = 1.04; 95% CI = [0.79, 1.37]; I2 = 12%), male sex (OR = 0.95; 95% CI = [0.49, 1.85]; I2 = 86%) and age over 65 (OR = 4.3; 95% CI = [0.25, 72.83]; I2 = 85%) were not associated with higher VTE risk. Conclusion: The VTE incidence following shoulder arthroscopy is low at 0.24%. Patients with BMI >30 and hypertension are at a higher risk for VTE after shoulder arthroscopy. Level of Evidence: Level IV, systematic review and meta-analysis of Level I-IV studies.

7.
Clin Biomech (Bristol, Avon) ; 120: 106346, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39303374

RESUMO

BACKGROUND: Stemless shoulder arthroplasty offers several advantages, such as preserving bone stock and reducing periprosthetic fracture risk. However, implant motion can deter osteointegration and increase bone resorption, where micromotion less than 0.150 mm is crucial for bony ingrowth and vital to the success of the implant. The interaction between the implant and the metaphyseal bone and its effects on stability remains unclear. Therefore, this cadaveric study aims to assess the immediate stability of two stemless prostheses in low bone density specimens. METHODS: Twenty cadaveric shoulders were used to compare the stability of two stemless shoulder implants by Zimmer-Biomet (model A) and Exactech (model B), subjected to loads of 220 N, 520 N, and 820 N to assess strain and micromotion. FINDINGS: Micromotion at 220 N load was 0.061 ± 0.080 mm and 0.053 ± 0.050 mm, and at 520 N load, 0.279 ± 0.37 mm and 0.311 ± 0.35 mm for models A and B, respectively. The estimated mean force required to achieve a 150 µm micromotion was 356 ± 116 N and 315 ± 61 N for models A and B, respectively. Motion analysis revealed distinct movement patterns for each implant, with model B demonstrating better force distribution on the bone despite no significance. INTERPRETATION: Forces over 520 N (high postoperative rehabilitation force) could hinder bone integration with prostheses due to excessive micromotion. Conversely, forces around 220 N (preconditioning loading force) are considered safe for prosthesis stability even with low bone density. These insights may caution against using stemless implants when bone density is low, and help guide clinical decisions on the duration of rehabilitation and sling use after stemless arthroplasty.

8.
Front Bioeng Biotechnol ; 12: 1450611, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39359266

RESUMO

Introduction: Over 6.8 million fractures occur annually in the US, with 10% experiencing delayed- or non-union. Anabolic therapeutics like PTH analogs stimulate fracture repair, and small molecule salt inducible kinase (SIK) inhibitors mimic PTH action. This study tests whether the SIK inhibitor YKL-05-099 accelerates fracture callus osteogenesis. Methods: 126 female mice underwent femoral shaft pinning and midshaft fracture, receiving daily injections of PBS, YKL-05-099, or PTH. Callus tissues were analyzed via RT-qPCR, histology, single-cell RNA-seq, and µCT imaging. Biomechanical testing evaluated tissue rigidity. A hydrogel-based delivery system for PTH and siRNAs targeting SIK2/SIK3 was developed and tested. Results: YKL-05-099 and PTH-treated mice showed higher mineralized callus volume fraction and improved structural rigidity. RNA-seq indicated YKL-05-099 increased osteoblast subsets and reduced chondrocyte precursors. Hydrogel-released siRNAs maintained target knockdown, accelerating callus mineralization. Discussion: YKL-05-099 enhances fracture repair, supporting selective SIK inhibitors' development for clinical use. Hydrogel-based siRNA delivery offers targeted localized treatment at fracture sites.

9.
Pain Res Manag ; 2023: 7054089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36819746

RESUMO

Background: Informed consent is the first step of every medical procedure and is considered a standard of care for patients undergoing medical interventions. Our study seeks to evaluate patients' understanding of the procedure they consented to and the factors affecting the degree of understanding. Methods: In this cross-sectional study, we used an anonymous postprocedural questionnaire to assess our patients' understanding of the procedure being performed and their level of satisfaction. It was conducted between June 2021 and January 2022 on every consenting patient who declined English interpreter services and was undergoing a first elective lumbar epidural steroid injection. Results: The mean age of 201 subjects was 57.3 (23-90) years, with a race distribution of Black (44.3%), White (31.8%), and other races (23.9%). 15.9% of our subjects worked in the medical field. Older age and patients identified as Black and other races had a positive correlation with the propensity to predict a poor understanding of consent. This study failed to demonstrate any difference in understanding of informed consent content between the different subgroups when stratified by assigned sex at birth, level of education, and profession. Patients' expectation from the treatment was classified as desperate (will take any help they can) in 78 patients (38.8%), feeling hopeful (expecting partial improvement in their symptoms) in 52 patients (25.9%), and being optimistic (will obtain full recovery from this injection) in 71 patients (35.3%). 192 patients (95.5%) were very satisfied with the consent process. Seven patients (3.5%) stated that they wanted more information, and 2 patients (1.0%) did not understand the explanation. 180 patients (89.6%) were satisfied with the overall experience, while 21 patients (10.4%) were not. The Wilks test (likelihood-ratio test) resulted in a p value of 0.023 and was deemed statistically significant for a relationship between understanding of consent and the satisfaction of the patient from the procedure. Conclusions: Although patients carry a variable expectation of procedures, most patients in our pain clinic have a high level of satisfaction despite having a poor understanding of the procedure provided via informed consent. Although our patients' level of objective comprehension is low, those with a better understanding of the procedure tend to have a more satisfactory experience.


Assuntos
Compreensão , Consentimento Livre e Esclarecido , Recém-Nascido , Humanos , Estudos Transversais , Inquéritos e Questionários , Dor
10.
Thyroid ; 33(7): 835-848, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37171127

RESUMO

Background: Anaplastic thyroid carcinoma (ATC) is a rapidly fatal cancer with a median survival of a few months. Enhanced therapeutic options for durable management of ATC will rely on an understanding of genetics and the role of the tumor microenvironment. The prognosis for patients with ATC has not improved despite more detailed scrutiny of underlying tumor genetics. Pericytes in the microenvironment play a key evasive role for thyroid carcinoma (TC) cells. Lenvatinib improves outcomes in patients with radioiodine-refractory well-differentiated TC. In addition to the unclear role of pericytes in ATC, the effect and mechanism of lenvatinib efficacy on ATC have not been sufficiently elucidated. Design: We assessed pericyte enrichment in ATC. We determined the effect of lenvatinib on ATC cell growth cocultured with pericytes and in a xenograft mouse model from human BRAFWT/V600E-ATC-derived cells coimplanted with pericytes. Results: ATC samples were significantly enriched in pericytes compared with normal thyroid samples. BRAFWT/V600E-ATC-derived cells were resistant to lenvatinib treatment shown by a lack of suppression of MAPK and Akt pathways. Moreover, lenvatinib increased CD47 protein (thrombospondin-1 [TSP-1] receptor) levels over time vs. vehicle. TSP-1 levels were downregulated upon lenvatinib at late vs. early time points. Critically, ATC cells, when cocultured with pericytes, showed increased sensitivity to this therapy and ultimately decreased number of cells. The coimplantation in vivo of ATC cells with pericytes increased ATC growth and did not downregulate TSP-1 in the microenvironment in vivo. Conclusions and Implications: Pericytes are enriched in ATC samples. Lenvatinib showed inhibitory effects on BRAFWT/V600E-ATC cells in the presence of pericytes. The presence of pericytes could be crucial for effective lenvatinib treatment in patients with ATC. Degree of pericyte abundance may be an attractive prognostic marker in assessing pharmacotherapeutic options. Effective durable management of ATC will rely on an understanding not only of genetics but also on the role of the tumor microenvironment.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Animais , Camundongos , Carcinoma Anaplásico da Tireoide/patologia , Pericitos/metabolismo , Pericitos/patologia , Trombospondina 1/uso terapêutico , Microambiente Tumoral , Proteínas Proto-Oncogênicas B-raf , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Modelos Animais de Doenças
11.
Ann Biomed Eng ; 51(5): 1002-1013, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36469168

RESUMO

Continuum mechanics-based finite element models of the shoulder aim to quantify the mechanical environment of the joint to aid in clinical decision-making for rotator cuff injury and disease. These models allow for the evaluation of the internal loading of the shoulder, which cannot be measured in-vivo. This study uses human cadaveric rotator cuff samples with surface tendon strain estimates, to validate a heterogeneous finite element model of the supraspinatus-infraspinatus complex during various load configurations. The computational model was considered validated when the absolute difference in average maximum principal strain for the articular and bursal sides for each load condition estimated by the model was no greater than 3% compared to that measured in the biomechanical study. The model can predict the strains for varying infraspinatus loads allowing for the study of load sharing between these two tightly coordinated tendons. The future goal is to use the modularity of this validated model to study the initiation and propagation of rotator cuff tear and other rotator cuff pathologies to ultimately improve care for rotator cuff tear patients.


Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Humanos , Manguito Rotador , Análise de Elementos Finitos , Fenômenos Biomecânicos
12.
J Bone Joint Surg Am ; 105(15): 1193-1202, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37339171

RESUMO

➤ Bone healing is commonly evaluated by clinical examination and serial radiographic evaluation. Physicians should be mindful that personal and cultural differences in pain perception may affect the clinical examination. Radiographic assessment, even with the Radiographic Union Score, is qualitative, with limited interobserver agreement.➤ Physicians may use serial clinical and radiographical examinations to assess bone healing in most patients, but in ambiguous and complicated cases, they may require other methods to provide assistance in decision-making.➤ In complicated instances, clinically available biomarkers, ultrasound, and magnetic resonance imaging may determine initial callus development. Quantitative computed tomography and finite element analysis can estimate bone strength in later callus consolidation phases.➤ As a future direction, quantitative rigidity assessments for bone healing may help patients to return to function earlier by increasing a clinician's confidence in successful progressive healing.


Assuntos
Consolidação da Fratura , Padrão de Cuidado , Humanos , Tomografia Computadorizada por Raios X/métodos , Exame Físico , Análise de Elementos Finitos
13.
J Biomech ; 156: 111664, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37302164

RESUMO

Tendinopathy is thought to be caused by repeated overload of the tendon with insufficient recovery time, leading to an inadequate healing response and incomplete recovery of preinjury material strength and function. The etiology of tendinopathy induced by mechanical load is being explored with a variety of mechanical load scenarios in small animals. This study establishes a testing system that applies passive ankle dorsiflexion to a rat hindlimb, estimates the force applied to the tendon during cyclic loading and enables the assessment of subsequent structural and biological changes. We demonstrated that the system had no drift in the applied angle, and the registered maximum angle and torque inputs and outputs were consistent between tests. We showed that cyclic loading decreased hysteresis and loading and unloading moduli with increasing cycles applied to the tendon. Histology showed gross changes to tendon structure. This work establishes a system for passively loading the rat Achilles tendon in-vivo in a physiological manner, facilitating future studies that will explore how mechanics, structure, and biology are altered by mechanical repetitive loading.


Assuntos
Tendão do Calcâneo , Tendinopatia , Ratos , Animais , Tendão do Calcâneo/fisiologia , Tornozelo , Articulação do Tornozelo/fisiologia , Fenômenos Mecânicos
14.
Arch Bone Jt Surg ; 8(3): 426-431, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32766403

RESUMO

BACKGROUND: Although some surgical techniques have been described for the operative treatment of unstable Osteochondritis dissecans (OCD) of the knee, outcomes are variable and are not satisfying totally. The aim of the present study is to evaluate the outcomes of autogenous osteochondral grafting for OCD of the knee. METHODS: In a case series study, from June 2014 to July 2015, 16 patients with stage II-IV OCD (International Cartilage Repair Society (ICRS)) of the femoral condyle were investigated. Surgical intervention considered in cases of stage III (4 cases) and IV (2 cases) and in stage II (10 cases) ones that were nonresponsive to conservative treatment. At the initial and final visits, the IKDC, Lysholm score and Tegner activity scale were evaluated. RESULTS: The mean preoperative IKDC score (53.4) increased significantly following surgery (84.3) (P<0.001). Based on the IKDC grading system, before the operation, the knee status was graded as nearly normal, abnormal, and severely abnormal in 4, 10, and 2 patients, respectively. At final post-surgical follow up, 15 normal and 1 abnormal knee were documented (P<0.001). The mean Lysholm score increased from 44.3 per operatively to 86.3 (P<0.001).Tegner activity score improved from 2.8±1 pre operatively to 5.6±2 (P<0.001). CONCLUSION: Surgical treatment of unstable OCD using autogenous osteochondral graft shows successful outcomes. In addition to reliable fixation, it can enhance healing and convert an uncontained lesion to contained one appropriate for autogenous osteochondral grafting with healthy cartilage.

15.
Arch Bone Jt Surg ; 8(5): 598-604, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33088861

RESUMO

BACKGROUND: The accuracy of reduction of ankle fractures using postoperative plain radiographies (x-ray) remains widely controversial. Some authors have demonstrated that postoperative computed tomography (CT) scan can be useful for these patients. In current study, the efficacy of x-rays after fixation of ankle fractures was investigated based on the CT scan findings. METHODS: A total of 73 patients with ankle fractures who were subjected to open reduction internal fixation (ORIF) were enrolled. After surgery, if the reduction was acceptable based on the x-rays according to standard measurements, the patient was referred for CT scanning. Forty four patients were included in the study. Undesirable CT scan findings including malreduction of fragments or articular surfaces, device malpositioning, missed fractures, and undetected intra-articular fragments were documented. RESULTS: Undesirable CT findings were seen in 25 patients (56.8%). CT scan showed acceptable reduction without device malpositioning in 19 patients. The most prevalent findings in CT images were malreduction and device malpositioning in 17 and 16 patients, respectively. There was no abnormal finding in CT imaging of lateral malleolar fractures. In two thirds of the injured syndesmosis, device malpositioning, and malreduction were detected in CT scan. CONCLUSION: Despite acceptable postoperative x-rays, a considerable number of patients with ankle fractures had inappropriate reduction or undesirable findings in their postoperative CT scan. It seems necessary to use CT scan after ORIF of ankle fractures in order to examine the accuracy of reduction. Further validation of postoperative CT scan in ankle fracture surgery should be investigated.

16.
Foot Ankle Int ; 41(1): 63-68, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31587569

RESUMO

BACKGROUND: The objective of this study was to determine whether the injection of botulinum toxin A (BTA) in the medial head of the gastrocnemius muscle could yield improvements in function and disability in patients with chronic plantar fasciitis with follow-up 12 months after treatment. METHODS: Thirty-two patients with chronic plantar fasciitis were included in the study and randomly allocated to the BTA and placebo groups. The visual analog scale (VAS) and American Orthopaedic Foot & Ankle Society (AOFAS) scores were used to evaluate pain levels pre- and postinjection as well as function of the foot, respectively. Patients were also asked to rate their treatment satisfaction 1 year after injection. The range of dorsiflexion was measured before and 12 months after the injection. RESULTS: At the 12-month follow-up, the mean VAS decreased from 7.8 to 4 in the placebo group and from 8 to 0.33 in the BTA group. Furthermore, the mean AOFAS scores increased from 48.4 to 65.3 in the placebo group and from 45.5 to 90.6 in the BTA group. The postinjection scores in the BTA group were significantly higher than those in the placebo group (P < .001). Patient satisfaction in the BTA group was higher than that in the placebo group at the 12-month follow-up. CONCLUSION: In patients with chronic plantar fasciitis, the use of BTA had a positive effect on improvement in pain and foot function 1 year after treatment. LEVEL OF EVIDENCE: Level I, prospective randomized controlled trial.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Fasciíte Plantar/terapia , Músculo Esquelético/efeitos dos fármacos , Adulto , Fasciíte Plantar/fisiopatologia , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Medição da Dor , Satisfação do Paciente , Estudos Prospectivos , Inquéritos e Questionários , Ultrassonografia de Intervenção
17.
Indian J Orthop ; 54(5): 655-664, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32850030

RESUMO

BACKGROUND: The earlier studies did not assess the associated factors of anterolateral ligament injury, comprehensively. We sought to evaluate the independent predictive factors of anterolateral ligament injury in the patients with anterior cruciate ligament tear. Ultrasound scan has an emerging role in the diagnosis of anterolateral ligament injury. MATERIALS AND METHODS: We included 198 patients with anterior cruciate ligament tear in this study. All the patients underwent knee ultrasound scan to diagnose the anterolateral ligament injury. The potential predictive factors of anterolateral ligament injury were compared between the patients with anterolateral ligament injury and the patients with the intact anterolateral ligament. RESULTS: In all the patients, the anterolateral ligament was seen in the tibial and femoral portions using the ultrasound scan. One hundred and ten patients (55.6%) had anterolateral ligament injury and the anterolateral ligament was intact in 88 patients (44.4%). The lateral collateral ligament injury was significantly associated with the anterolateral ligament injury (p < 0.001). In addition, the iliotibial band injury had a significant relationship with the anterolateral ligament injury (p = 0.001). An increased lateral tibial slope was significantly associated with the anterolateral ligament injury (p = 0.031). Furthermore, the bone contusion of the lateral femoral condyle had a significant relationship with the anterolateral ligament injury (p = 0.004). CONCLUSION: The independent predictors of anterolateral ligament injury included the lateral collateral ligament injury, iliotibial band injury, bone contusion of the lateral femoral condyle, and an increased lateral tibial slope.

19.
Arch Bone Jt Surg ; 7(4): 354-359, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31448313

RESUMO

BACKGROUND: The prevention of surgical site infection is one of the most concerning issues in operating rooms. Surgical gowns are worn as one of the intraoperative strategies for infection prevention. The present study investigated whether the gowns remained sterile during the surgical procedure. Furthermore, this study examined which parts of the surgical gown were more prone to contamination. METHODS: The sterility of the gowns was investigated during eight total joint arthroplasties all of which were performed by four surgeons. The samples were taken from the arms and frontal part of the sterile gowns pre- and postoperatively. In the anterior surface of the gown, the sampling was initiated at a strip with 50 cm height from the ground followed by the strips with 15 cm distances from caudal to cephalad. Furthermore, the frontal part of the gown was divided into three parts in relation to the operating room table. Finally, the contamination rate was evaluated in each part. A semiquantitative method was used for the analysis of bacterial culture. RESULTS: Before the operation, there were four samples tested positive for bacterial culture (1.06%). All of these samples were taken from the most proximal strip near the neckline. After the surgery, the rate of contamination in the strips on the frontal part of the gown was reported as 3.1% to 53%. Based on the operating table, the contamination rate was 35.9%, 8.9%, and 47.3% in the distal, middle, and proximal parts of the gown, respectively. The contamination rate at the elbow crease was 23%, and at 5 and 10 cm above the creases were 24% and 36%, respectively. CONCLUSION: The high rate of gown contamination during the operation is concerning. However, part of the gown that was in contact with the operating room table remained clean most of the time. More safe strategies should be used for infection prevention in operating rooms.

20.
Bull Emerg Trauma ; 7(2): 150-155, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31198804

RESUMO

OBJECTIVE: To compare the efficacy of parasagittal interlaminar (PIL) and midline interlaminar (MIL) approaches for epidural block in patients with lower limb orthopedic surgery. METHODS: This double-blind randomized clinical trial was performed on 40 patients undergoing tibial shaft fracture surgery. In PIL group, an 18-gauge, 3.5 inch, Tuohy needle was placed at the level of L2-3 or L3-4 intervertebral spaces and pushed forward in a posteroanterior (PA) direction vertical to the body surface. After determining the most lateral place for needle arrival in an anteroposterior (AP) view, needle was pushed forward into the epidural space. For the MIL group, needle was pushed forward from the midline interspinous space with the same method. After confirmation of needle position, 1 mL of contrast was injected to confirm the epidural space distribution and then 15 ml lidocaine 2% was injected. The sensory and motor block level, onset, duration, heart rate (HR), mean arterial pressure (MAP), and arterial oxygen saturation (SPO2), and success rate were recorded. RESULTS: Mean patients' baseline characteristics showed no statistically significant difference between the two groups.p>0.05). Outcome measures were statistically different and significantly higher in PIL group (p-values for sensory block level <0.001, motor block level <0.001, duration of sensory block: <0.001 and duration of motor block <0.001 and success rate: <0.001). Hemodynamic variables didn't show statistically significant difference between the two groups (p-values for Systolic pressure: 0.997, diastolic pressure:0.579, MAP:0.585, HR:0.710). CONCLUSION: Epidural anesthesia with parasagittal interlaminar approach provide deep motor block, high sensory level block, and hemodynamic stability. CLINICAL TRIAL REGISTRY: IRCT2017041615515N2.

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