Investigation on three-dimensional temperature field of human knee considering anatomical structure

  • Wenzhou Medical University, Wenzhou, China
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Inappropriate heat and mass transfer is an extremely important factor to cause rheumatics of human knee which however receives few attentions up to now. Understanding the thermal behaviors of pathological knee tissues can help diagnose its pathological status and find out the most efficient therapeutical way, which is hard to access otherwise. This paper is dedicated to develop a theoretical model for characterizing the three-dimensional temperature fields of human knee by taking its real anatomical structure into consideration. Based on the classical Pennes bioheat transfer equation, the temperature fields of normal knees and pathological ones under various thermal conditions were numerically simulated and compared, which would help better understand the disease mechanisms causing trouble for human knee. Meanwhile, a medical infrared image system was adopted to map the surface temperature of human knee which qualitatively verifies the theoretical prediction and its diagnostic value. Further, effects of heating from outside on the knee tissue and interventional hyperthermia based on vessel heating were also evaluated. Potential therapeutical strategies were suggested for the thermal rehabilitation of rheumatic knee in the near future.

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... However, experimental measurements of temperature profile in the human body present great difficulties because of its invasive nature, the limited positioning of sensors, the imprecision of the data obtained and ethical issues linked to in vivo experiments (Trobec et al., 2008). Yet, the studies investigating temperature behavior in living tissues (Trobec et al., 2008;Xiao et al.,2010;Silva, 2011;Trobec and Depolli, 2011;Narasimhan and Jha, 2012) have grown steadily since 1948 when Harry Pennes proposed the first model of bio-transfer heat that related the temperature of biological tissues to blood perfusion and the generation of metabolic heat based on his experiments (Pennes, 1948). This model is known as the Pennes bio-transfer heat equation. ...
... For the skin, there is a difference of 8.9% between the results. According to Xiao et al. (2010), the temperature of the skin in the condition of thermal neutrality is between 30.2 and 32.8 ° C. It does not show the temperature of the other tissues. This greater difference found between the temperatures in the skin is due to the different conditions of air temperature and convective coefficient adopted in the three studies: Trobec et al. (2008) considers the ambient temperature at 27 ° C and Xiao et al. (2010) ...
... According to Xiao et al. (2010), the temperature of the skin in the condition of thermal neutrality is between 30.2 and 32.8 ° C. It does not show the temperature of the other tissues. This greater difference found between the temperatures in the skin is due to the different conditions of air temperature and convective coefficient adopted in the three studies: Trobec et al. (2008) considers the ambient temperature at 27 ° C and Xiao et al. (2010) ...
... Theoretical studies of brain hypothermia have been attracted great attention because experimental methods are relatively difficult to perform. Many previous studies have modeled the heat transfer in the brain by using Pennes bioheat equation because of its simplicity, effectiveness, and ease of application; this equation has successfully predicted the temperature distributions in kidney cortexes [17], knees [18], canine prostates [19], feet [20], and brains [5e12]. Solving the Pennes bioheat equation is difficult because of its complicated form for the differential equation and the tissues. ...
... Solving the Pennes bioheat equation is difficult because of its complicated form for the differential equation and the tissues. Various numerical methods [5e12, 18,21e36], including finite difference method [5,6,8,9,21e24], finite volume method [10,18], finite element method [7,9,11,12,25,26], boundary element method [27e32], meshless method [33], control volume method [34] and numerical Green's approach [35], have been widely used to solve the Pennes bioheat equation. Among them, for solving the Pennes bioheat equation for the brain, finite difference method [5,6,8,9], finite volume method [10], and finite element method [7,9,11,12], have been used. ...
... Chua et al. used the Pennes bioheat equation to predict the temperature distribution within the human eye that is subjected to a laser source, and reported that the agreement between the model and experimental data up to 5% [24]. Xiao et al. developed by Pennes bioheat equation a heat transfer model for characterizing the three dimensional temperature fields of human knee, and they qualitatively validated the model by using a medical infrared image system to map the surface temperature of human knee [25]. Chen and Xu investigated the heat transfer in the kidney phantom during water-bath heating [26]. ...
... It is difficult to solve the bioheat equations because of its complicated forms of the differential equation and the tissues. Various numerical methods, including finite difference method [2,8,29], finite volume method [25], finite element method [30], boundary element method [31e33], meshless method [34], and numerical Green's approach [35], have been widely used to solve the Pennes bioheat equation. On the other hand, analytical solutions to the Pennes bioheat equation are also derived by applying the methods of Green's function [36e39], separation of variables [40,41], and Laplace transform [42,43]. ...
... However, the method taking the temperature distribution and temperature difference information of body surface as the basis for diagnosis of diseases has many limitations, because it is ignored that the internal thermal distribution of lesion in human body carries lots of valuable disease information, which is of great importance for the diagnosis of diseases [15][16][17][18]. At present, the medical imaging technologies being commonly used such as magnetic resonance imaging (MRI), X-CT imaging, ultrasonic imaging etc., can provide some related biochemical and pathologic information, nevertheless these technologies have a fundamental constraint, that is they can only display the shape changes of body tissue, but not reflect functional changes of body tissue [19,20]. When the structural lesions emerge in the human body, the qualitative changes of the patient's condition have taken place [21][22][23][24][25]. ...
... In order to mine the valuable 3-dimensional heat distribution data based on temperature distribution of body surface, many research groups have carried out in-depth studies and made a series of achievements [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. This present paper aims to acquire the q-r characteristic curve of the heat intensity varying with depth of tomography based on the temperature distribution characteristics of tumor in different stages. ...
Heat is the product following the metabolism of cells, and the metabolism is closely related with the pathological information of living organism. So, there are strong ties between the heat distribution and the pathological state in living organism. In this paper, the mathematical function δ is introduced in the classical Pennes bio-heat transfer equation as the point heat source. By simplifying the boundary conditions, a novel bio-heat transfer model is established and solved in a spherical coordinate system. Based on the temperature distribution of human body surface, the information of heat source is mined layer by layer, and the corresponding q-r curve of heat intensity varying with depth is acquired combining the fitting method of Lorentz curve. According to a large number of clinical confirmed cases and statistics, the diagnostic criteria judging diseases by q-r curve are proposed. Five typical clinical practices are performed and four of the diagnosis results are very consistent with those of molybdenum target (MT) X-ray, B-ultrasonic images and pathological examination, one gives the result of early stage malignant tumor that MT X-ray and B-ultrasonic can’t check out. It is a radiation-free green method with noninvasive diagnostic procedure and accurate diagnosis result.
... The distribution of heat in the human knee was described by Xiao et al. [24]. Taking into account the anatomical structure of human knee, Xiao et al. developed a theoretical model for three-dimensional temperature Reumatologia 2018; 56/5 fields of the human knee. ...
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Hyperthermia is a method applied in the treatment of many diseases, including rheumatic diseases. There are relatively few reports concerning the role of that method in the treatment of these diseases, and most studies have not been randomised. Hyperthermia includes directed application of thermal energy. The aim of that therapy is to overcome the body's natural thermoregulation mechanism through application of external heat sources such as electromagnetic radiation of various frequencies, or ultrasound. Usually, temperatures are used within the 38.5-43° range. Hyperthermia can be applied as topical, regional, or systemic treatment (the latter is called hyperthermia of the whole body). In rheumatology, mainly the effect of hyperthermia on the immune system of the body is used. That effect depends on the type of hyperthermia and temperatures applied. Best documented are the effects of hyperthermia in fibromyalgia and ankylosing spondylitis.
... However, given the paucity of experimental data for comparison, it is not possible to assess the impact of this consideration on the found studies. Xiao et al. [26] performed numerical simulations to assess the contributions of temperature fields in normal and pathological knees on the effect of heating. The geometric model used for simulation considered only the skin, muscle, bone and blood vessels. ...
Tissue heating is used for the treatment of health disorders. However, the benefits of this therapy depend heavily on the temperature reached in the tissues. Values outside the ideal range recommended for therapeutic effects may result in ineffective or tissue-damaging treatments. Thus, understanding the heat transfer process and knowing the temperature distribution in biological tissues are essential factors for this treatment to be applied safely and effectively. In this context, the numerical simulation becomes an interesting tool to understand the temperature field in the different tissues that make up the joint and, thus, to contribute to a better application of the thermal resources used in the clinical practice of physiotherapy. This study aimed to simulate the transient heat transfer in a canine knee joint during the application of a therapeutic heating feature and to investigate the effects of blood perfusion performed at a constant rate (A1 simulation) and as a function of tissue temperature distribution (A2 simulation). The heat diffusion equation was used to model the heat transfer phenomenon. The simulations were performed using the ANSYS-CFX® program. The results obtained from the simulations were compared with in vivo experimental data. The A1 simulation showed a maximum percentage difference of 25.6% compared to the experimental data. In contrast, the highest percentage difference found for the A2 simulation was 9.8%. In conclusion, the results suggest that simulation can be an important tool to evaluate the temperature behaviour of biological tissues during the application of thermal therapeutic resources.
... In order to obtain the thermal behaviors for the EED/skin system, the bio-heat transfer in human skin tissue is necessarily considered, which has been investigated in many articles [22][23][24][25][26][27]. Human skin can be divided into three layers: epidermis layer, dermis layer and fat layer from outside to inside, whose thermal parameters (e. g. conductivities and diffusivities) are totally different. ...
... Despite the many advantages of numerical simulations, it is known that the considerations included in computational problem solutions can strongly influence the results and generate an incorrect interpretation of the heat transfer process. In the studies found in the literature, boundary conditions and the adopted considerations may have no justification, and numerous simplifications may have been made (XIAO et al., 2011;XUE;LIU, 2013). In addition, the results from the simulations are rarely compared with actual data (experimental in vivo), which leaves doubt about the veracity of the simulated data. ...
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This study aimed to simulate heat transfer in thermal equilibrium in the canine knee joint. We analyzed the impact of different values of blood perfusion available in the literature and considered blood perfusion rates. The geometric models of canine knee joints were created from a photographic record of a cross section of an anatomical part. Two geometric models were developed: one without the epidermis and one with the epidermis. A heat diffusion equation was used to model the heat transfer phenomenon. Numerical simulations of the canine knee in a thermal neutrality condition were performed using the ANSYS-CFX® program. The simulation results were compared with experimental in vivo data. The smaller percentage differences between the experimental and simulated in vivo results were found in simulations that used the blood flow rate as a function of temperature. The computer simulation proved to be a good alternative to evaluate the temperature of biological tissues. © 2016, Universidade Federal de Uberlandia. All rights reserved.
... For an actual hyperthermia or cryosurgery, various composite structures are always encountered. This poses an ever tough issue to compute the reality as could as possible [48]. Modeling such bioheat transfer problem relies on the precise quantification on the desired target (see example (Fig. 7E). ...
... In 1948, Pennes et al. established the well known Pennes bioheat transfer equation that is recognized as the most suitable one in all bioheat transfer models so far. Its typical form can be expressed as follows [6]: ...
The noninvasive detection and reconstruction of 3D temperature field in a biological body have received increasing attention in bio-medical engineering field. Based on the classical Pennes bioheat transfer equation, the heat transfer mathematical model fitting for breast tissue is founded in this paper. Meanwhile, using the large analysis software ANSYS, the modeling and simulating of heat transfer in pork and intravital breast tissue are presented combining with Finite Element Method (FEM). The result shows, the 3D temperature field can be well reconstructed efficiently, which will play a positive role in promoting many research field such as tumor thermotherapy, cryosurgery, cryo-preservation of biomaterial and so on. © 2015 Binary Information Press & Textile Bioengineering and Informatics Society.
... An anatomical CAD model of human knee ( Fig. 1) has been established in our previous work [22]. The tissue structures are composed of skin, large arterial and venous vessels, muscle and bones, which contain femoral, patella, tibia and fibular, respectively. ...
This paper is aimed at investigating the capacity of using combined cryosurgical and hyperthermic modality for treating knee bone tumor with complex shape. An anatomical model for human knee was constructed and a three-dimensional (3D) finite element analysis was developed to determine temperature distribution of the tissues subject to single freezing (SF), single heating (SH) and alternate freezing-heating (AFH), respectively. The heat fluxes of the probes wall and the ablation volume are particularly tracked to comparatively evaluate the ablation ability of different probe configurations with varied diameter, number and active working length. As example, an effective conformal treatment strategy via one time's insertion while cyclic freezing-heating using multiple probes is designed for a predefined knee bone tumor ablation. Both SF and SH could create large enough ablation volume, while it is hard for them to perform a conformal treatment on irregular and slender knee tumor. As an alternative, AFH could form a flexible and controlled shape and volume of the ablation by changing the size and number of the probes and adjusting their insertion depth. In addition, a thermal protection method is considered to reduce cryoinjury of the health tissue.
... Furthermore, in (35) authors analyzed temperature changes in young and elderly subjects during exercise and presented that both groups have similar capacity for heat production and that elderly subjects have a lower resting temperature and slower heat dissipation. Authors in (36) investigate the heat transfer based on the optical flow through a 3D temperature field of a human knee in order to prove diagnostic significance of thermal behavior in determining the pathological status, and propose several therapeutic strategies for the rheumatic knee. Moreover, evaluation of whole body thermal adaptation during physical exercise can help determine ideal conditions for physical activities (37). ...
The dissipation of thermal radiation can be observed using thermal infrared cameras which generate images based on the amount of input radiation belonging to a small part of the electromagnetic spectrum (with wavelengths from 7 μmto 15 μm). Since thermal imaging is a simple, contactless, non-invasive and inexpensive imaging method, it is widely applicable in industry, medicine and research. The most common type of thermal imaging involves taking and analyzing only a single thermal image, and it is thus called static thermal imaging. In cases when a thermal process cannot be approximated as static, dynamic thermal imaging and analysis are applied. The idea of combining thermal imaging with 3D scanning methods has spawned in the last few years. 3D thermal imaging can have many applications and purposes, ranging from thermogram rectification to the creation of standardized 3D thermal models of various subjects that can later be used for comparison and evaluation. Although 3D thermal imaging systems exist, all of the examined ones were targeted on the acquisition and analysis of static 3D thermal models. This paper presents the development of a 4D thermography system through integration of dynamic 3D scanning and thermographic imaging, additionally providing markerless motion analysis, which together enable practical, non-invasive, accurate and automatic monitoring of the temperature changes in the human body, and the characterization of human motion. The workflow of the designed concept is outlined, and the components of the constructed system are thoroughly explained. The process of calibration of the system is described, as well as the methods of motion detection and analysis. Great emphasis is given on the possible medical applications of a 4D thermography system, such as medical diagnostics, human locomotive system rehabilitation and health status monitoring over prolonged time periods.
The thermophysical properties of bone cement are important parameters for its application in the orthopedic treatment. This article focused on the thermal evaluation of the low-melting-point metal (BiInSn alloy), which has been proved to be an excellent bone cement. Firstly, the basic thermophysical properties of BiInSn alloys with different melting points were measured. Secondly, 15 fresh porcine femurs placed in the saline bath, bone cements with different melting points and amounts were injected into the bone cavities, respectively. Thermocouples were used to measure the temperature changes of the bone-cement interface and peripheral bone tissue. The possibility of thermal necrosis was evaluated. Moreover, a three-dimensional human knee model was built to numerically assess the effects of thermal parameters, such as melting point and latent heat on tissue temperature distribution. All the experimental and numerical results implied the heat distribution in the tissue depended on the thermal performances of liquid metal bone cement (LMBC). For LMBC of the same melting point, with increased amounts, the damage to the bone tissue is more severe, while for the same amount of different melting point LMBCs, with the higher melting point, which will lead to more serious damage to the tissue. Also, higher latent heat of LMBC has distinct longer solidification process, which may cause irreversible damage to surrounding tissues. Therefore, in the future, for different clinical surgery needs, the appropriate liquid metal bone cement can be obtained by adjusting the thermal parameters.
Metabolic heat, the product following the metabolism of cells, is closely related to the pathological information of living organisms, which means there are strong connections between the heat distribution and the pathological state of the living organism. The mathematical function δ is introduced in the classical Pennes bioheat transfer equation as a point heat source, and by simplifying the boundary condition, a bioheat transfer model is established. Based on the temperature distribution of the human body surface, the q−r curve of heat intensity q varying with depth r is acquired while combining the fitting method of the Lorentz curve. According to 34,977 clinical confirmed cases and the corresponding classified statistics, diagnostic criteria (for breast diseases) for judging diseases by the q−r curve are proposed. The P -value of our statistics is <0.05 , which means our classified statistics are reliable. Six typical clinical examinations are performed, and the diagnosis results are very consistent with those of B-ultrasonic images, molybdenum target x-ray, and pathological examination, which suggests that the method of diagnosing diseases with a q−r curve has very good prospects for application. It is radiation free and noninvasive to the human body.
Embedding a thermoelectric generator (TEG) in a biological body is a promising way to supply electronic power in the long term for an implantable medical device (IMD). It can resolve the service life mismatch between the IMD and its battery. This paper is dedicated to developing a real prototype, which consists of an implanted TEG and a specified boosted circuit. Two implanted TEG modules were constructed and a boosted circuit with a highly integrated DC/DC converter was fabricated to stabilizing the energy output and improving the voltage output for the implanted TEG. According to the experiments, such a device combination was already capable of supporting a clock circuit in the in vivo rabbit whose power consumption is much higher than an ordinary cardiac pacemaker. Meanwhile, a close to reality theoretical model was established for characterizing the implanted TEG. This study is expected to serve as a valuable reference for future designs of the implanted TEG and its boosted circuit.
Conference Paper
The unique merit of the implantable thermoelectric generator lies in its direct utilization of the temperature difference intrinsically existing throughout the whole biological body. Therefore, it can resolve the service life mismatch between the IMD and its battery. In order to promoting the TEG maximum power, a piece of radioisotope fuel was fixed on the TEG hot junction. Recurring to the thermal energy released during disintegration of radioactive isotope, it can guarantee a marked promotion in the temperature difference across the implanted TEG; consequently apply enough power for the IMDs.
When there exist diseases or functional changes in a certain part of the human body, the speed of blood flow and cell metabolism will change correspondingly, which will lead to the thermal variation in this area. To find out the relation between disease and heat distribution, a suitable bio-heat transfer model is established in this paper. Based on the infrared thermal image of human body surface, the q–r characteristic curve of heat intensity varying with depth is acquired combining the fitting method of Lorentz curve. According to a large number of clinical cases and statistics, the diagnostic criteria judging diseases by q–r characteristic curve are proposed. Several clinical practices are performed and the diagnosis results are very consistent with those of molybdenum target (MT) X-ray and B-ultrasonic images. It is a radiation-free green method with rapid diagnostic procedure and accurate diagnosis result.
In the present paper a description for thermal diffusion and diffusion thermo effect of thixotropic fluid through biological tissues investigated mathematically. The comparison between variational iteration method (VIM) and Homotopy perturbation methods (HPM) for solving system of non linear partial differential equations describing the momentum, energy, mass and bioheat transfer has been discussed. The effects of the model parameters on shear stress of the fluid, tissue temperature, concentrations and fluid temperature have been plotted graphically.
This paper is dedicated to present a comprehensive investigation on the thermal effects of large blood vessels of human knee joint during topical cooling and fomentation treatment. A three-dimensional (3D) finite element analysis by taking full use of the anatomical CAD model of human knee joint was developed to accurately simulate the treatment process. Based on the classical Pennes bio-heat transfer equation, the time evolution of knee joint's temperature distribution and heat flux from large blood vessels was obtained. In addition, we compared several influencing factors and obtained some key conclusions which cannot be easily acquired through clinical experiments. The results indicated that the thermal effects of large blood vessels could remarkably affect the temperature distribution of knee joint during treatment process. Fluctuations of blood flow velocity and metabolic heat production rate affect little on the thermal effects of large blood vessels. Changing the temperature of blood and regimes of treatment could effectively regulate this phenomenon, which is important for many physiological activities. These results provide a guideline to the basic and applied research for the thermally significant large blood vessels in the knee organism.
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Conventional nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a spectrum of toxic effects, notably gastrointestinal (GI) effects, because of inhibition of cyclooxygenase (COX)-1. Whether COX-2-specific inhibitors are associated with fewer clinical GI toxic effects is unknown. To determine whether celecoxib, a COX-2-specific inhibitor, is associated with a lower incidence of significant upper GI toxic effects and other adverse effects compared with conventional NSAIDs. The Celecoxib Long-term Arthritis Safety Study (CLASS), a double-blind, randomized controlled trial conducted from September 1998 to March 2000. Three hundred eighty-six clinical sites in the United States and Canada. A total of 8059 patients (>/=18 years old) with osteoarthritis (OA) or rheumatoid arthritis (RA) were enrolled in the study, and 7968 received at least 1 dose of study drug. A total of 4573 patients (57%) received treatment for 6 months. Patients were randomly assigned to receive celecoxib, 400 mg twice per day (2 and 4 times the maximum RA and OA dosages, respectively; n = 3987); ibuprofen, 800 mg 3 times per day (n = 1985); or diclofenac, 75 mg twice per day (n = 1996). Aspirin use for cardiovascular prophylaxis (</=325 mg/d) was permitted. Incidence of prospectively defined symptomatic upper GI ulcers and ulcer complications (bleeding, perforation, and obstruction) and other adverse effects during the 6-month treatment period. For all patients, the annualized incidence rates of upper GI ulcer complications alone and combined with symptomatic ulcers for celecoxib vs NSAIDs were 0.76% vs 1.45% (P =.09) and 2. 08% vs 3.54% (P =.02), respectively. For patients not taking aspirin, the annualized incidence rates of upper GI ulcer complications alone and combined with symptomatic ulcers for celecoxib vs NSAIDs were 0.44% vs 1.27% (P =.04) and 1.40% vs 2.91% (P =.02). For patients taking aspirin, the annualized incidence rates of upper GI ulcer complications alone and combined with symptomatic ulcers for celecoxib vs NSAIDs were 2.01% vs 2.12% (P =.92) and 4.70% vs 6.00% (P =.49). Fewer celecoxib-treated patients than NSAID-treated patients experienced chronic GI blood loss, GI intolerance, hepatotoxicity, or renal toxicity. No difference was noted in the incidence of cardiovascular events between celecoxib and NSAIDs, irrespective of aspirin use. In this study, celecoxib, at dosages greater than those indicated clinically, was associated with a lower incidence of symptomatic ulcers and ulcer complications combined, as well as other clinically important toxic effects, compared with NSAIDs at standard dosages. The decrease in upper GI toxicity was strongest among patients not taking aspirin concomitantly. JAMA. 2000;284:1247-1255
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To examine the potential usefulness of a novel thermal imaging technique to evaluate and monitor inflammatory arthritis activity in small joints using rat models, and to determine whether thermal changes can be used to detect preclinical stages of synovitis. Three different rat strains were studied in a model of inflammatory arthritis of the ankle induced by an intra-articular (IA) injection of complete Freund's adjuvant (CFA), compared with the contralateral ankle injected with normal saline. Arthritis activity and severity scores, ankle diameters, pain related posture scores, and thermal images were obtained at 10 different times between 0 h (before induction) and day 7. The pristane induced arthritis (PIA) model was used to study preclinical synovitis. Thermal images were obtained at each time point using the TSA ImagIR system and were digitally analysed. Rats developed similar ankle arthritis detected six hours after the IA injection of CFA, which persisted for seven days. All ankle clinical indices, including arthritis activity and severity scores, correlated significantly with ankle thermal imaging changes in the monoarthritis model (p<0.003). No thermal imaging changes were detected in preclinical stages of PIA. However, PIA onset coincided with increased ankle thermal signature. Thermal measurements correlated significantly with arthritis activity and severity indices. The technique was highly sensitive and could measure directly two cardinal signs of inflammation (warmth and oedema, based on ankle diameter) in an area (ankle) that is less than half the size of a human interphalangeal joint, suggesting a potential use in drug trials or clinical practice.
Aim: To analyze the guiding significance to the designing of prosthesis by measuring of the morphologic dimensions data of the distal part of the femur and the proximal part of the tibia of the osteotomied face and the patella. Methods: This clinical trial was carried out in Department of Orthopedic Surgery, General Hospital of Chinese PLA from February to May 2005 in 77 patients (105 knees) included 23 men (32 knees) and 54 women (73 knees). They were measured during total knee arthroplasty (TKA) and the patella was kept in the operation. The morphologic dimensions data of the distal part of the femur and the proximal part of the tibia of the osteotomied face and the patella were measured. All the measured data were involved in the statstical analysis. The different observational index was calculated; mean value and standard deviation of the above were summed up by stats 8.0 software. Coefficient correlation and regression equation among the width of femoral condyle, width of lower femoral codyle, width of femoral condyle (A, B, C) and the width of tibial platform, sagittal length of medial & lateral tibial platform were got at the same time. Results: A total of 105 injured knee joints were involved in the result analysis. The proportion of each parameter of femoral condyle and tibial platform was defined. 1 There was linear correlation between the width of femoral condyle A and C (P < 0.05)coefficient correlation:0.758 3, regression equation: A=-1.523+0.754 C. 2 There was linear correlation between the width of femoral condyle B and C (P < 0.05) coefficient correlation:0.855 5, regression equation:B=5.774 6+0.819 7 C. 3 There was linear correlation between the width of tibial platform and the femoral condyle C (P < 0.05)coefficient correlation:0.859 6, regression equation: M= 24.634 9+0.702 1 C. 4The width of tibial platform and the sagittal length of medial tibial platform correlated to each other (P < 0.05) coefficient correlation: 0.830 6, regression equation: L=-7.801 0+0.772 9 M. 5 The width of tibial platform and sagittal length of lateral tibial platform correlated to each other (P < 0.05) coefficient correlation: 0.728 8, regression equation: N=-1.740 5+0.612 9 M. 6 Sagittal length of lateral tibial platform was shorter than sagittal length of medial tibial platform by 5.76 mm. Conclusion: The study measures and adds up exactly geometrical morphological dimensions of Chinese's knee joint, and provides reference data of distal part of the femur and the proximal part of the tibia of the osteotomied face and the patella of the adult's abnormal knees. The results are close to the Chinese anatomical structure so it can provide more scientific evidence to the designing and manufacturing of knee joint prosthesis. The application of these data will improve the fitness degree of the prosthesis in order to elevate the clinical effect of the TKA.
Local topical cooling with gel-packs or cryo-cuffs is often used after surgery or after knee injuries. Mostly beneficial, but some deleterious effects have been reported in literature. The spatial distribution of heat/cold through different tissues of the knee in time may be responsible for different effects of cooling on the traumatized or inflamed tissue and have yet to be studied. Parallel computer simulation was used to study, non-invasively, temperature changes in the knee during cooling. A 3-D computer model of the knee, with a spatial resolution of 1mm, was derived from cross sections available in the visible human dataset. Heat transfer in a non-homogenous knee tissue was modeled with a diffusion equation, which was solved by the explicit finite difference method. The heat transfer between blood and tissue and tissue metabolism have also been modeled and simulated. Two different simulations were performed: cooling with a liquid at constant temperature (cryo-cuff) and topical cooling with frozen gel-packs. The simulated results were analyzed and compared with relevant measurements.
This work was designed to test the hypothesis that elevations in body temperature of humans induce immunostimulation. Eight healthy volunteers were immersed in a water bath (water temperature 39.5 degrees C) for 2 h, during which their rectal temperature rose to 39.5 degrees C. On a later day they served as their own controls, being immersed into thermoneutral water (34.5 degrees C) for 2 h. Blood samples were collected before immersion, at body temperatures of 38 degree C, 39 degree C and 39.5 degree C, and 2 h after water immersion. The interleukin-2 (IL-2) enhanced natural killer (NK) cell activity (lysis per fixed number of mononuclear cells), as well as the proportion and total number of NK cells (CD16+ cells), increased significantly during hyperthermia compared with control values. The lymphocyte proliferative responses did not differ significantly between hyperthermia and thermoneutral conditions. The proportion of pan-T (CD3+) cells was maximally depressed 2 h after water immersion. The decreased proportion of CD3+ cells was mainly due to a decreased percentage of CD4+ cells (not significant). The proportion of B cells (CD19+ cells) did not fluctuate significantly, while a marked and significant increase in monocyte proportion (CD14+ cells) was found 2 h after hyperthermia. Two hours after hot water immersion the lymphocyte concentration declined while the neutrophil and monocyte concentrations were augmented. Induced hyperthermia causes significantly increased serum cortisol, plasma norepinephrine and plasma epinephrine concentrations compared to controls. It is possible that the altered immune functions induced by elevated body temperature can be ascribed to altered composition and function of blood mononuclear cells induced by elevated levels of stress hormones.
Local deep microwave hyperthermia (LDMWH) may be considered as a therapeutic tool for joint diseases because it has the advantage of heating the target organ e.g. synovium, while sparing the adjacent tissues, as demonstrated in animals. The effect of this new microwave device has been evaluated on seven rheumatoid arthritis patients with knee effusion. The hyperthermia apparatus consists of a 915 MHz power source with a cooling system to the skin. LDMWH was operated for one hour, twice a week for two weeks. Intra-articular knee temperature reached the level of 40.6±1.1 °C within 15 minutes, raised to 41.2±0.7°C after 30 minutes and to 41.3±0.9°C at one hour. The skin temperature over the heated knee joints remained at 24.3±1.1°C during treatment. All patients noted a sensation of warmth in the treated knee. Aspiration of synovial fluid was performed before and immediately after each treatment. Walking time was improved (p=0.04) and significant decrease in pain (p=0.01) was noted following treatment. Synovial fluid leukocyte count and prostaglandin E 2level, knee circumference and range of motion did not change. Severity of pain, walking time, knee circumference and range of motion remained stable in the six weeks following the last hyperthermia application. No adverse reaction could be observed. These results suggest LDMWH to be safe and successful as an adjuvant treatment of chronic inflammatory joint effusions.
This is a review of modalities, mechanism of action, rationale and list of conditions commonly treated by heat and cold. In all conditions, heat and cold therapy are used only as an adjunct to other management; in none can heat or cold therapy be considered as curative.
Though heat has been used for many years for the treatment of painful joints such therapy rarely increases the intra-articular temperature significantly. This pilot study investigated the effect of intra-articular hyperthermia induced by microwaves from a combined heating/cooling instrument on zymosan-induced synovitis in the rabbit. There was histological evidence not only of a reduction in the intensity of the inflammatory response but also in its type with the absence of giant cell formation. However, hyperthermia was not totally without effect on the synovium of control joints and further studies are required to investigate the relevance of this effect.
A two-dimensional mathematical model was developed to estimate the contributions of different mechanisms of brain cooling during cold-water near-drowning. Mechanisms include 1) conductive heat loss through tissue to the water at the head surface and in the upper airway and 2) circulatory cooling to aspirated water via the lung and via venous return from the scalp. The model accounts for changes in boundary conditions, blood circulation, respiratory ventilation of water, and head size. Results indicate that conductive heat loss through the skull surface or the upper airways is minimal, although a small child-sized head will conductively cool faster than a large adult-sized head. However, ventilation of cold water may provide substantial brain cooling through circulatory cooling. Although it seems that water breathing is required for rapid "whole" brain cooling, it is possible that conductive cooling may provide some advantage by cooling the brain cortex peripherally and the brain stem centrally via the upper airway.
In non-invasive thermal diagnostics, accurate correlations between the thermal image on skin surface and interior human pathophysiology are often desired, which require general solutions for the bioheat equation. In this study, the Monte Carlo method was implemented to solve the transient three-dimensional bio-heat transfer problem with non-linear boundary conditions (simultaneously with convection, radiation and evaporation) and space-dependent thermal physiological parameters. Detailed computations indicated that the thermal states of biological bodies, reflecting physiological conditions, could be correlated to the temperature or heat flux mapping recorded at the skin surface. The effect of the skin emissivity and humidity, the convective heat transfer coefficient, the relative humidity and temperature of the surrounding air, the metabolic rate and blood perfusion rate in the tumor, and the tumor size and number on the sensitivity of thermography are comprehensively investigated. Moreover, several thermal criteria for disease diagnostic were proposed based on statistical principles. Implementations of this study for the clinical thermal diagnostics are discussed.
Basic Technology of Vascular Intervention
  • F J Criado
F.J. Criado, Basic Technology of Vascular Intervention, Phoenix Science Press, Nanjing, 2003. in Chinese.
Physical Thermal Method and Application in SARS Medicine
  • J Liu
J. Liu, Physical Thermal Method and Application in SARS Medicine, Science Press, Beijing, 2004. in Chinese.
The effect of hyperthermia (42·5∘C) on zymosan-induced synovitis of the knee, British society for rheumatology 33
  • I Otremski
  • G Erling
  • Z Cohen
  • R J Newman
Geometry of chinese knee and measurement of its parameter, Medical journal of chinese people’s liberation army 27
  • M J Sun
  • Y Wang
  • J Y Chen
  • X G Yang
  • X H Jiang
  • L Liu
  • J Cui