3D Printing as a Way of Integrating Mathematical Models in Arthroscopic Knee Surgery

2018 ◽  
Vol 69 (9) ◽  
pp. 2501-2507
Author(s):  
Anca Plavitu ◽  
Mark Edward Pogarasteanu ◽  
Marius Moga ◽  
Mircea Lupusoru ◽  
Florentina Ionita Radu ◽  
...  
Keyword(s):  
Knee Joint ◽  
Osteochondral Defect ◽  
Surgical Intervention ◽  
Operating Time ◽  
Vascular Pathology ◽  
Osteochondral Lesions ◽  
Joint Surfaces ◽  
Novel Method ◽  
Technological Means ◽  
Arthroscopic Knee

Our objective is to develop a novel method of approaching the arthroscopic treatment of osteochondral lesions within the knee joint by using mathematics as a way of understanding the geometry involved in the knee, both in normal and degenerated knee joint surfaces. Bone and cartilage lesions are frequent, whether as a result of trauma, degenerative pathology, vascular pathology (osteocondritis dissecans) or tumoral. In all cases, a defect can be repaired arthroscopically, if it has manageable dimensions and if the surgeon has the technological means and the necessary skills, through the use of grafts (autografts or allografts). Alternatively, a lesion that may be approached arthroscopically initially could prove to be too great for repair and may need a second intervention for reconstruction with an endoprosthesis. We aim to further deepen the surgeon�s understanding of this pathology, through the use of 3D technology as a way of representing the osteochondral defect. Thus, its dimensions and position may be better understood, and the surgical intervention may be better planned out, potentially resulting in a shorter operating time and an overall superior outcome for the patient, and even potentially diminishing the number of unnecessary surgeries performed.

scholarly journals A novel method for the assessment of knee joint space width and subchondral bone micro architecture

2016 ◽  
Vol 24 ◽  
pp. S379
Author(s):  
R. Ljuhar ◽  
B. Norman ◽  
D. Ljuhar ◽  
T. Haftner ◽  
J. Hladuvka ◽  
...  
Keyword(s):  
Knee Joint ◽  
Subchondral Bone ◽  
Joint Space Width ◽  
Joint Space ◽  
Novel Method ◽  
Space Width

scholarly journals The Assessment of the Condition of Knee Joint Surfaces with Acoustic Emission Analysis

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6495
Author(s):  
Bartłomiej Sawaryn ◽  
Natalia Piaseczna ◽  
Szymon Sieciński ◽  
Rafał Doniec ◽  
Konrad Duraj ◽  
...  
Keyword(s):  
Knee Joint ◽  
Knee Injury ◽  
Knee Joints ◽  
Resonance Imaging ◽  
Emission Analysis ◽  
X Ray ◽  
Joint Surfaces ◽  
Magnetic Resonance Imaging Mri ◽  
Leg Movements ◽  
Acoustic Emission Analysis

The knee joint, being the largest joint in the human body, is responsible for a great percentage of leg movements. The diagnosis of the state of knee joints is usually based on X-ray scan, ultrasound imaging, computerized tomography (CT), magnetic resonance imaging (MRI), or arthroscopy. In this study, we aimed to create an inexpensive, portable device for recording the sound produced by the knee joint, and a dedicated application for its analysis. During the study, we examined fourteen volunteers of different ages, including those who had a knee injury. The device effectively enables the recording of the sounds produced by the knee joint, and the spectral analysis used in the application proved its reliability in evaluating the knee joint condition.

Diagnostic Value of MRI and Radiographs of the Knee to Identify Osteochondral Lesions in Acute Patellar Instability

2021 ◽  
Author(s):  
Hayden Baker ◽  
Jason Dickherber ◽  
Manoj Reddy ◽  
Andrew Rizzi ◽  
Adam Kahn ◽  
...  
Keyword(s):  
Patellar Instability ◽  
Osteochondral Defect ◽  
Knee Arthroscopy ◽  
Cruciate Ligament ◽  
Diagnostic Value ◽  
Mpfl Reconstruction ◽  
Osteochondral Lesions ◽  
Loose Bodies ◽  
Plain Radiographs ◽  
Diagnostic Arthroscopy

AbstractThe purpose of this study was to define the diagnostic value of magnetic resonance imaging (MRI) and plain radiographs (X-ray [XR]) in identifying an osteochondral defect or loose body in patients undergoing operative treatment for patellar instability. A total of 87 patients treated operatively for patellar instability with medial patellofemoral ligament (MPFL) reconstruction between 2015 and 2019 were identified. Inclusion criteria were evidence of clinical patellar instability, preoperative XR and MRI studies, and concomitant diagnostic knee arthroscopy and MPFL reconstruction performed to address patellar instability. Patients were excluded if they had a history of prior procedure for patellar instability on the surgical knee, underwent MPFL reconstruction without concomitant diagnostic knee arthroscopy, or had an anterior cruciate ligament or posterior cruciate ligament deficient knee. Operative notes and arthroscopic images were reviewed to identify osteochondral or chondral injuries and loose bodies noted during diagnostic arthroscopy. The primary outcome was the identification of intra-articular loose bodies, chondral injury, or osteochondral defect on preoperative plain radiographs and MRI in patients with patellar instability. All MRIs were performed on a 3T MRI. The sensitivity and specificity of identifying loose bodies on MRI were 0.52 and 0.92 and on XR were 0.23 and 0.98, respectively. The sensitivity and specificity of identifying osteochondral lesions on MRI were 0.43 and 0.81 and on XR were 0.08 and 0.97, respectively. Of the 87 available reports, 45 (51%) described performing chondroplasty for Outerbridge grade II/III chondral lesions on diagnostic arthroscopy. In conclusion, MRI and XR are poorly sensitive at identifying loose bodies or osteochondral defects after patellar dislocations. The poor sensitivity of imaging studies must be considered when determining whether or not to recommend operative management to a patient with patellar instability. This is a Level IV, diagnostic study.

Autogenous Osteochondral Grafting for Treating Osteochondral Defect of the Femoral Condyle of the Knee Joint

2009 ◽  
Vol 44 (3) ◽  
pp. 301 ◽  
Author(s):  
Seung Suk Seo ◽  
Chang Wan Kim ◽  
Dong Jun Ha ◽  
Jang Seok Choi ◽  
Ho Jun Kim ◽  
...  
Keyword(s):  
Knee Joint ◽  
Osteochondral Defect ◽  
Femoral Condyle ◽  
Osteochondral Grafting

P164. Adjacent Level Effects: A Novel Method for Assessing Kinematic Changes of the Entire Thoracolumbar Spine Following Surgical Intervention

2009 ◽  
Vol 9 (10) ◽  
pp. 198S-199S
Author(s):  
Erin Campbell ◽  
Kyle Elsabee ◽  
John Wason ◽  
John Wen ◽  
Allen Carl ◽  
...  
Keyword(s):  
Surgical Intervention ◽  
Thoracolumbar Spine ◽  
Adjacent Level ◽  
Novel Method ◽  
Adjacent Level Effects

scholarly journals How does intraarticular dexmedetomidine injection effect articular cartilage and synovium? An animal study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Başak Akça ◽  
Aysun Ankay Yılbaş ◽  
Filiz Üzümcügil ◽  
Berkem Büyükakkuş ◽  
Elham Bahador Zırh ◽  
...  
Keyword(s):  
Pain Relief ◽  
Knee Joint ◽  
Animal Study ◽  
Left Knee ◽  
Control Group ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Arthroscopic Knee ◽  
The Right

Abstract Background Intraarticular injections are widely used to provide pain relief after arthroscopic procedures and minimize the use of opioids. Dexmedetomidine has been proven to potentiate pain relief and postpone the demand for the first analgesic drug when it is used intraarticularly following arthroscopic knee procedures. However, the effects of dexmedetomidine on articular structures have not yet been evaluated. Our aim was to determine the effects of intraarticular dexmedetomidine injection on articular structures such as cartilage and synovium. Design Animal study. Methods Twenty adult rats (Sprague-Dawley) were enrolled in the study. Following appropriate aseptic and anesthetic conditions, dexmedetomidine (100 mcg/ml) (0.25 ml) was injected into the right knee joint (the study group) and normal saline solution (0.25 ml) into the left knee joint (the control group) of the rats. Four rats were sacrificed from each group on days 1, 2, 7, 14, and 21, and knee joint samples were obtained. Histologists evaluated the articular and periarticular regions and the synovium using histological sections, and a five-point scale was used to grade the inflammatory changes in a blinded manner. Results The groups were found to be similar in terms of median congestion scores, edema and inflammation scores, subintimal fibrosis, neutrophil activation and cartilage structure at each of the time intervals. Conclusion In our placebo-controlled, in vivo trial, the intraarticular use of dexmedetomidine seemed to be safe with respect to the studied histopathological parameters. However, complementary studies investigating the histopathological effects, analgesic dosage and adverse effects of dexmedetomidine on damaged articular structure models are needed.

scholarly journals Successful laparoscopic surgery combined with selective arterial embolization for bleeding due to jejunal angiodysplasia: a case report

BMC Surgery ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Hitoshi Hara ◽  
Soji Ozawa ◽  
Kazuhito Nabeshima ◽  
Jun Koizumi
Keyword(s):  
Small Intestine ◽  
Small Bowel ◽  
Contrast Agents ◽  
Surgical Intervention ◽  
Treatment Plan ◽  
Indigo Carmine ◽  
Arterial Embolization ◽  
Vascular Pathology ◽  
Selective Arterial Embolization ◽  
Small Bowel Bleeding

Abstract Background Angiodysplasia of the gastrointestinal tract is a rare vascular pathology that sometimes causes massive hemorrhage. Angiodysplasias are particularly difficult to find in the small intestine for anatomical reasons, often impeding their diagnosis and treatment. Lesion localization is a major challenge in cases of small bowel bleeding requiring surgical intervention. Case presentation The present case was a 52-year-old woman who was urgently hospitalized with repeated tarry stools. Surgical intervention was chosen after conservative treatment failed to improve her condition. The source of bleeding was suspected to be a vascular lesion discovered in the small intestine during a past double-balloon endoscopy. Abdominal contrast computed tomography revealed a jejunal hemorrhage. We chose selective arterial embolization to stabilize her hemodynamics followed by surgical intervention as her treatment plan. Several embolic and contrast agents (cyanoacrylate, indigo carmine, and Lipiodol) were combined to help identify the location of the lesion during surgery. This multi-pronged approach allowed us to localize the lesion under laparoscopic guidance with high confidence and accuracy, and to excise a 6-cm segment of the small intestine. The lesion was histologically diagnosed as angiodysplasia. No re-bleeding has been observed since the operation. Conclusion We report our experience with a case of jejunal angiodysplasia, which was localized with selective arterial embolization using an array of embolic and contrast agents, and then excised laparoscopically. Selective arterial embolization with indigo carmine dye to treat small bowel bleeding preoperatively not only makes the surgery safer by stabilizing the patient’s hemodynamics, but is also very useful for localizing the lesion intraoperatively.

SYNCHRONOUS-TO-ASYNCHRONOUS CONVERSION OF CRYPTOGRAPHIC CIRCUITS

2009 ◽  
Vol 18 (02) ◽  
pp. 271-282 ◽  
Author(s):  
RICARDO F. CASSIA ◽  
VLADIMIR C. ALVES ◽  
FEDERICO G.-D. BESNARD ◽  
FELIPE M. G. FRANÇA
Keyword(s):  
Functional Unit ◽  
Operating Time ◽  
New Method ◽  
Clock Tree ◽  
Standard Cells ◽  
Synchronization Algorithm ◽  
Asynchronous Scheduling ◽  
Novel Method

This paper introduces a novel method for the conversion of synchronous cryptographic circuits into equivalent asynchronous ones. The new method is based on ASERT (Asynchronous Scheduling by Edge Reversal Timing), a fully decentralized timing signaling and synchronization algorithm. From a synthesizable HDL code, an asynchronous timing network, made from standard cells libraries, is generated in order to replace the clock tree of the target circuit. ASERT works with matched delays, local clocks or any equivalent way of determining, statically or dynamically, the operating time of each functional unit. Synchronous to asynchronous conversion of three different cryptographic circuits, including the fully synthesized netlists of AES, Reed-Solomon decoder, and RSA cipher cores, are presented.

Bone necrosis due to decompression

1984 ◽  
Vol 304 (1118) ◽  
pp. 185-191 ◽  
Keyword(s):  
Knee Joint ◽  
Compressed Air ◽  
Long Bone ◽  
Miniature Pig ◽  
Bone Necrosis ◽  
Joint Surfaces ◽  
Bone Damage ◽  
Specialist Knowledge ◽  
Detection And Diagnosis

Death of areas of long bone has been known to be associated with work in compressed air and diving for many years. Detection and diagnosis require specialist knowledge, but familiarity with the condition has increased markedly over the last 20 years. Most of it is symptomless and causes no disability, but if areas adjacent to the joint surfaces of the upper end of the humerus and the upper end of the femur are affected, the joint may be seriously damaged and disability ensue. This problem has been defined by surveys of groups of workers using compressed air and divers in an attempt to establish prevalence. In general the more diving undertaken and the deeper the dives, the more probability there is of acquiring bone damage. The commonest area to be affected is the lower end of the femur, but the knee joint is never involved. The cause of bone damage is far from clear. None of the various explanations that have been offered are satisfactory, but research continues into the problem both in humans and in animals, particularly the miniature pig. At present it is difficult to quantify the risk taken by commercial divers in relation to changing technology either in terms of depth or duration of pressure.

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