Sol-gel dip-coated TiO2 nanofilms reduce heat production in titanium alloy implants produced by microwave diathermy.

Objective: To verify that the TiO2 nanofilm dip-coated by sol-gel can reduce titanium alloy implants (TAI)'s heat production after microwave diathermy (MD).Methods: The effect of 40 W and 60 W MD on the titanium alloy substrate coated with TiO2 nanofilm (Experimental Group) and the titanium alloy substrate without film (Control Group) were analyzed in vitro and in vivo. Changes in the skeletal muscle around the implant were evaluated in ex vivo by histology.Results: After 20 min of MD, in vitro the temperature rise of the titanium substrate was less in the Experimental Group than in the Control Group (40 W: 1.4 °C vs. 2.6 °C, p < .01, 60 W: 2.5 °C vs. 3.7 °C, p < .01) and in vivo, the temperature rise of the muscle tissue adjacent to TAI was lower in the Experimental Group than in the Control Group (40 W: 3.29 °C vs. 4.8 °C, p < .01, 60 W: 4.16 °C vs. 6.52 °C, p < .01). Skeletal muscle thermal injury can be found in the Control Group but not in the Experimental Group.Conclusion: Sol-gel dip-coated TiO2 nanofilm can reduce the heat production of TAIs under single 40～60 W and continuous 40 W MD and protect the muscle tissue adjacent to the implants against thermal injury caused by irradiation.

Prevention of muscle atrophy in ICU patients without nerve injury by neuromuscular electrical stimulation: a randomized controlled study.

BACKGROUND: Extensive muscle atrophy is a common occurrence in orthopaedics patients who are bedridden or immobilized. The incidence is higher in intensive care unit (ICU) inpatients. There is still controversy about how to use neuromuscular electrical stimulation (NMES) in ICU patients. We aim to compare the effectiveness and safety of NMES to prevent muscle atrophy in intensive care unit (ICU) patients without nerve injury. METHODS: ICU patients without central and peripheral nerve injury were randomized into experimental group I (Exp I: active and passive activity training (APAT) + NMES treatment on the gastrocnemius and tibialis anterior muscle), experimental group II (Exp II: APAT + NMES treatment on gastrocnemius alone), and control group (Ctl: APAT alone). Changes in the strength of gastrocnemius, the ankle range of motion, and the muscle cross-section area of the lower leg were evaluated before and after the intervention. Also, changes in prothrombin time, lactic acid, and C-reactive protein were monitored during the treatment. RESULTS: The gastrocnemius muscle strength, ankle joint range of motion, and cross-sectional muscle area of the lower leg in the three groups showed a downward trend, indicating that the overall trend of muscle atrophy in ICU patients was irreversible. The decrease in gastrocnemius muscle strength in Exp I and Exp II was smaller than that in the control group (P < 0.05), but there was no difference between Exp I and Exp II. The decrease in active ankle range of motion and cross-sectional area of the lower leg Exp I and Exp II was smaller than that in the control group (P < 0.05), and the decrease in Exp I was smaller than that of Exp II (all P < 0.05). The curative effect in Exp I was better than in Exp II. There were no significant differences in the dynamic changes of prothrombin time, lactic acid, and C-reactive protein during the three groups (P > 0.05). CONCLUSION: In addition to early exercise training, NMES should be applied to prevent muscle atrophy for patients without nerve injury in ICU. Also, simultaneous NMES treatment on agonist/antagonist muscle can enhance the effect of preventing muscle atrophy. TRIAL REGISTRATION: This study was prospectively registered in China Clinical Trial Registry ( www.chictr.org.cn ) on 16/05/2020 as ChiCTR2000032950.

Study on TiO2 Nanofilm That Reduces the Heat Production of Titanium Alloy Implant in Microwave Irradiation and Does Not Affect Fracture Healing.

Background: Metal implants can produce heat and damage adjacent tissues under microwave irradiation, which makes local metal implants in the body a contraindication for microwave therapy. However, with the wide application of titanium alloy implants which have low permeability and low conductivity, this concept has been challenged. Our team members have confirmed through previous research that continuous low-power microwave irradiation does not cause thermal damage to the surrounding tissues of the titanium alloy. Is there any other way to further increase the dose of microwave irradiation while reducing the heat production of titanium alloy implants? In this study, the effect of TiO2 nanofilm on reducing the heat production of titanium alloy implants in microwave field was verified by animal experiments, and the effect of TiO2 nanofilm on fracture healing was observed. Methods: 30 rabbits were selected. In the experiment of temperature measurement, 10 rabbits were randomly divided into experimental group (n = 5) and control group (n = 5), and the contralateral lower limb of the rabbits in experimental group was set as the sham operation group. The right femurs in the experimental group were implanted with Ti6Al4V plates coated with TiO2 nanofilm, and the right femurs in the control group were implanted with common titanium alloy plates without TiO2 nanofilm. The same surgical procedure was used in the sham operation group, but no plate was implanted. The temperature of the deep tissue above the metal implant was measured with an anti-interference thermocouple thermometer during 20 minutes of microwave irradiation. The other 20 rabbits were randomly divided into two groups, experimental group (n = 10) and control group (n = 10). The femoral shaft fracture models were established again. Ti6Al4V plates coated with TiO2 nanofilm and common titanium alloy plates were implanted in the two groups, respectively, and both groups were exposed to continuous microwave irradiation with a power of 40 W or 60 W for 30 days after operation. The fracture healing was evaluated by X-ray at 0 day, 14 days, and 30 days after microwave irradiation, respectively. The animals were sacrificed at 30 days after operation for histopathological assessment. Results: The temperature in the experimental group, control group, and sham operation group increased significantly after 40 W and 60 W microwave irradiation (2.18 ± 0.15°C~6.02 ± 0.38°C). When exposed to 40 W microwave, the temperature rise of the control group was 4.0 ± 0.34°C, which was significantly higher than that of the experimental group 2.82 ± 0.15°C (P < 0.01) and the sham operation group 2.18 ± 0.33°C (P < 0.01). There was no significant difference in temperature rise between the experimental group and the sham operation group (P = 0.21). When exposed to 60 W microwave, the temperature rise of the control group was 6.02 ± 0.38°C, which was significantly higher than that of the experimental group 3.66 ± 0.14°C (P < 0.01) and sham operation group 2.96 ± 0.22°C (P < 0.01), and there was no significant difference between the experimental group and the sham operation group (P = 0.32). X-ray evaluation showed that there was no significant difference in callus maturity between the experimental group and the control group at 14 days (P = 0.554), but there was significant difference in callus maturity between the two groups at 30 days (P = 0.041). The analysis of bone histologic and histomorphometric data at 30 days was also consistent with this. Conclusion: Under the animal experimental condition, compared with the common titanium alloy implant, the TiO2 nanofilm can reduce the heat production of the titanium alloy implant in the 2450 MHz microwave field and has no adverse effect on fracture healing. This study opens up a promising new idea for the application of microwave therapy to metal implants in human body.

Comparative study of the proliferative ability of skeletal muscle satellite cells under microwave irradiation in fractures with titanium alloy internal fixation in rabbits.

The aim of the present study was to investigate the proliferation of skeletal muscle satellite cells (MSCs) under different amounts of microwave irradiation in fractures with titanium alloy internal fixation. A total of 45 male New Zealand adult white rabbits were used to establish a femoral shaft fracture and titanium alloy internal fixation model. The rabbits were randomly divided into the control group (group A) and the experimental groups (groups B and C). For 15 days, groups B and C were exposed to microwave treatment (25 or 50 W, respectively) for 10 min per day. The quadriceps femoris muscle was used for the isolation and culture of MSCs in vitro. The cultured cells were identified using cellular immunohistochemical staining. Transmission electron microscopy was used to observe mitochondrial ultrastructure damage, MTT assays were used to detect cell viability and cell cycle phases were analyzed by flow cytometry. The results revealed that, following 48 or 72 h of culture, cell viability was significantly greater in group B compared with group A, and was significantly lower in group C compared with group A (P<0.05). Compared with group A, the percentage of the cell population in the G0/G1 phase in group B was significantly decreased (P<0.05) and the proportion in the S and G2/M phases was increased (P<0.05). These results were reversed in group C; the percentage of cells in the S and G2/M phases was significantly lower (P<0.05) and in the G0/G1 phase was significantly higher (P<0.05) than in group A. These results suggested that in the healing of fractures with titanium, the proliferation of MSCs is significantly affected by microwave radiation in a dose-dependent manner.

[Information Management System for Rehabilitation Medicine Department of General Hospital].

OBJECTIVES: To develop a common information management system for rehabilitation medicine department of general hospital. METHODS: Based on the investigation of information requirement of several different levels hospitals, the medical information management system was designed, and it has been applied in several hospitals. RESULTS: In addition to rehabilitation treatment informatization for inpatient and outpatient, the system has highly customizable, assistant research, teaching and management features. CONCLUSIONS: The system can simplify the process of medical treatment, improve the efficiency of diagnosis and treatment, increase patient satisfaction, improve the management level. It worths popularizing.

Enhancement of Apoptosis by Titanium Alloy Internal Fixations during Microwave Treatments for Fractures: An Animal Study.

OBJECTIVE: Microwaves are used in one method of physical therapy and can increase muscle tissue temperature which is useful for improving muscle, tendon and bone injuries. In the study, we sought to determine whether titanium alloy internal fixations influence apoptosis in tissues subjected to microwave treatments at 2,450 MHz and 40 W during the healing of fractures because this issue is not yet fully understood. METHODS: In this study, titanium alloy internal fixations were used to treat 3.0-mm transverse osteotomies in the middle of New Zealand rabbits' femurs. After the operation, 30-day microwave treatments were applied to the 3.0 mm transverse osteotomies 3 days after the operation. The changes in the temperatures of the muscle tissues in front of the implants or the 3.0 mm transverse osteotomies were measured during the microwave treatments. To characterize the effects of titanium alloy internal fixations on apoptosis in the muscles after microwave treatment, we performed TUNEL assays, fluorescent real-time (quantitative) PCR, western blotting analyses, reactive oxygen species (ROS) detection and transmission electron microscopy examinations. RESULTS: The temperatures were markedly increased in the animals with the titanium alloy implants. Apoptosis in the muscle cells of the implanted group was significantly more extensive than that in the non-implanted control group at different time points. Transmission electron microscopy examinations of the skeletal muscles of the implanted groups revealed muscular mitochondrial swelling, vacuolization. ROS, Bax and Hsp70 were up-regulated, and Bcl-2 was down-regulated in the implanted group. CONCLUSION: Our results suggest that titanium alloy internal fixations caused greater muscular tissue cell apoptosis following 2,450 MHz, 40 W microwave treatments in this rabbit femur fracture models.

Thermal effects of 2450 MHz microwave exposure near a titanium alloy plate implanted in rabbit limbs.

This study aimed to examine the safety profile of microwave therapy on limbs with metal implants. New Zealand white rabbits were implanted with titanium alloy internal fixation plates. Femurs were exposed to 20, 40, 60, or 80 W of microwave radiation for 30 min (microwave applicator at 2450 MHz), and temperatures of the implants and muscles adjacent to implants were recorded. To evaluate thermal damage, nerves were electrodiagnostically assessed immediately after radiation, and histologic studies performed on nerve and muscle sections. As expected, implant temperature was highest in the exposure field. Temperatures of limbs with titanium alloy implants increased significantly at 60 and 80 W, with a significant decline in the nerve conduction velocity and acute thermal injuries in nerves and muscles adjacent to implants. However, temperature remained unchanged and no adverse effects were observed in nerves and muscles at 20 and 40 W. These findings are inconsistent with the current notion that surgical metal implants in the treatment field are contraindications for microwave therapy. Hence, we believe that a lower dose of continuous wave microwave irradiation is safe for limbs with titanium alloy implants.

Carpal tunnel syndrome assessment with ultrasonography: value of inlet-to-outlet median nerve area ratio in patients versus healthy volunteers.

OBJECTIVE: To evaluate the diagnostic value of the Inlet-to-outlet median nerve area ratio (IOR) in patients with clinically and electrophysiologically confirmed carpal tunnel syndrome (CTS). METHODS: Forty-six wrists in 46 consecutive patients with clinical and electrodiagnostic evidence of CTS and forty-four wrists in 44 healthy volunteers were examined with ultrasonography. The cross-sectional area (CSA) of the median nerve was measured at the carpal tunnel inlet (the level of scaphoid-pisiform) and outlet (the level of the hook of the hamate), and the IOR was calculated for each wrist. Ultrasonography and electrodiagnostic tests were performed under blinded conditions. Electrodiagnostic testing combined with clinical symptoms were considered to be the gold standard test. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic value between the inlet CSA and IOR. RESULTS: The study population included 16 men and 30 women (mean age, 45.3 years; range, 18-83 years). The control population included 18 men and 26 women (mean age, 50.4 years; range, 18-79 years). The mean inlet CSA was 8.7 mm2 in healthy controls and 14.6mm2 in CTS group (P<0.001). The mean IOR in healthy volunteers (1.0) was smaller than that in patients (1.6, P<0.001). Receiver operating characteristic analysis revealed a diagnostic advantage to using the IOR rather than the inlet CSA (P<0.01). An IOR cutoff value of ≥ 1.3 would yield 93% specificity and 91% sensitivity in the diagnosis of CTS. CONCLUSION: The IOR of median nerve area promises to be an effective means in the diagnosis of CTS. A large-scale, randomized controlled trial is required to determine how and when this parameter will be used.

Low dose of continuous-wave microwave irradiation did not cause temperature increase in muscles tissue adjacent to titanium alloy implants--an animal study.

BACKGROUND: Research studies on the influence of radiofrequency electromagnetic radiation on implants in vitro have failed to investigate temperature changes in the tissues adjacent to the implants under microwave therapy. We therefore, used a rabbit model in an effort to determine the impact of microwave therapy on temperature changes in tissues adjacent to the titanium alloy implants and the safety profile thereof. METHODS: Titanium alloy internal fixation plates were implanted in New Zealand rabbits in the middle of femur. Microwave therapy was performed by a 2450 MHz microwave generator 3 days after the surgery. Temperature changes of muscles adjacent to the implants were recorded under exposure to dose-gradient microwave radiation from 20w to 60w. RESULTS: Significant difference between control and microwave treatment group at peak temperatures (T(peak)) and temperature gap (T(gap) = T(peak)-T(vally)) were observed in deep muscles (T(peak), 41.63 ± 0.21°C vs. 44.40 ± 0.17°C, P < 0.01; T(gap), 5.33 ± 0.21°C vs. 8.10 ± 0.36°C, P < 0.01) and superficial muscles (T(peak), 41.53 ± 0.15°C vs. 42.03 ± 0.23°C, P = 0.04; T(gap), 5.23 ± 0.21°C vs. 5.80 ± 0.17°C, P = 0.013) under 60 w, and deep muscles (T(peak), 40.93 ± 0.25°C vs. 41.87 ± 0.23°C, P = 0.01; T(gap), 4.73 ± 0.20°C vs. 5.63 ± 0.35°C, P = 0.037) under 50w, but not under 20, 30 and 40w. CONCLUSION: Our results suggest that low-dose (20w-40w) continuous-wave microwave irradiation delivered by a 2450 MHz microwave generator might be a promising treatment for patients with titanium alloy internal fixation, as it did not raise temperature in muscle tissues adjacent to the titanium alloy implant.

Effects of low-dose microwave on healing of fractures with titanium alloy internal fixation: an experimental study in a rabbit model.

BACKGROUND: Microwave is a method for improving fracture repair. However, one of the contraindications for microwave treatment listed in the literature is surgically implanted metal plates in the treatment field. The reason is that the reflection of electromagnetic waves and the eddy current stimulated by microwave would increase the temperature of magnetic implants and cause heat damage in tissues. Comparing with traditional medical stainless steel, titanium alloy is a kind of medical implants with low magnetic permeability and electric conductivity. But the effects of microwave treatment on fracture with titanium alloy internal fixation in vivo were not reported. The aim of this article was to evaluate the security and effects of microwave on healing of a fracture with titanium alloy internal fixation. METHODS: Titanium alloy internal fixation systems were implanted in New Zealand rabbits with a 3.0 mm bone defect in the middle of femur. We applied a 30-day microwave treatment (2,450MHz, 25W, 10 min per day) to the fracture 3 days after operation. Temperature changes of muscle tissues around implants were measured during the irradiation. Normalized radiographic density of the fracture gap was measured on the 10th day and 30th day of the microwave treatment. All of the animals were killed after 10 and 30 days microwave treatment with histologic and histomorphometric examinations performed on the harvested tissues. FINDINGS: The temperatures did not increase significantly in animals with titanium alloy implants. The security of microwave treatment was also supported by histology of muscles, nerve and bone around the implants. Radiographic assessment, histologic and histomorphometric examinations revealed significant improvement in the healing bone. CONCLUSION: Our results suggest that, in the healing of fracture with titanium alloy internal fixation, a low dose of microwave treatment may be a promising method.

Comparative study of microRNA profiling in keloid fibroblast and annotation of differential expressed microRNAs.

Keloids are tumor-like skin scars that grow as a result of the aberrant healing of skin injuries, with no effective treatment. The molecular mechanism underlying keloid pathogenesis is still largely unknown. In this study, we compared microRNA (miRNA) expression profiles between keloid-derived fibroblasts and normal fibroblasts (including fetal and adult dermal fibroblasts) by miRNA microarray analysis. We found that the miRNA profiles in keloid-derived fibroblasts are different with those in normal fibroblasts. Nine miRNAs were differentially expressed, six of which were significantly up-regulated in keloid fibroblasts (KFs), including miR-152, miR-23b-3p, miR-31-5p, miR-320c, miR-30a-5p, and hsv1-miR-H7, and three of which were significantly down-regulated, including miR-4328, miR-145-5p, and miR-143-3p. Functional annotations of differentially expressed miRNA targets revealed that they were enriched in several signaling pathways important for scar wound healing. In conclusion, we demonstrate that the miRNA expression profile is altered in KFs compared with in fetal and adult dermal fibroblasts, and the expression profile may provide a useful clue for exploring the pathogenesis of keloids. miRNAs might partially contribute to the etiology of keloids by affecting several signaling pathways relevant to scar wound healing.

[Design & development of the stroke rehabilitation evaluation system].

The stroke rehabilitation evaluation system has been designed and developed in view of the present practice status of clinical rehabilitation medicine. The system not only implements patient information collection and rehabilitation evaluation, but also outputs individual rehabilitation program automatically according to evaluation outcome.

[Design & development progress of the computer rehabilitation evaluation system].

This review paper presents the current design & development progress and challenges of computer rehabilitation evaluation system.

[Experimental study on regeneration of sciatic nerve injury with physical therapy].

OBJECTIVE: Peripheral nerve injury is a common clinical disease, to study the effects of the physical therapy on the regeneration of the injured sciatic nerve, and provide a reference for clinical treatment. METHODS: Sixty-four female adult Wistar rats (weighing 252-365 g) were chosen and randomly divided into 4 groups (n = 16): group A, group B, group C, and group D. The experimental model of sciatic nerve defect was established by crushing the right sciatic nerve in groups B, C, and D; group A served as the control group without crushing. At 2 days after injury, no treatment was given in group B, electrical stimulation in group C, and combined physical therapies (decimeter and infrared ray) in group D. At 0, 7, 14, and 30 days after treatment, the sciatic nerve function index (SFI) and the motor nerve conduction velocity (MNCV) were measured, and morphological and transmission electron microscopy (TEM) examinations were done; at 30 days after treatment, the morphological evaluation analysis of axons was performed. RESULTS: At 0 and 7 days after treatment, the SFI values of groups B, C, and D were significantly higher than that of group A (P < 0.05); at 14 and 30 days after treatment, the SFI value of group D decreased significantly, no significant difference was observed between group D and group A (P > 0.05) at 30 days; whereas the SFI values of groups B and C decreased, showing significant difference when compared with the value of group A (P < 0.05). At 0, 7, and 14 days after treatment, the MNCV values of groups B, C, and D were significantly lower than that of group A (P < 0.05), and there were significantly differences between group B and groups C, D (P < 0.05); at 14 days, the MNCV value of group D was significantly higher than that of group C (P < 0.05); and at 30 days, the MNCV values of groups B and C were significantly lower than that of group A (P < 0.05), but there was no significant difference between group D and group A (P > 0.05). At 0 and 7 days, only collagen and lipid were observed by TEM; at 14 and 30 days, many Schwann cells and perineurial cells in regeneration axon were observed in groups B, C, and D, especially in group D. Automated image analysis of axons showed that there was no significant difference in the number of myelinated nerve fibers, axon diameter, and myelin sheath thickness between group D and group A (P > 0.05), and the number of myelinated nerve fibers and axon diameter of group D were significantly higher than those of groups B and C (P < 0.05). CONCLUSION: Physical therapy can improve the regeneration of the injured sciatic nerve of rats.

Autografting satellite cells to repair damaged muscle induced by repeated compression: an animal model.

BACKGROUND: Repeated elevation of intramuscular pressure (IMP) causes skeletal-muscles damage. The purpose of this paper was to investigate the regenerative effect of satellite cells autografted to the damaged muscle in a rabbit model. MATERIALS AND METHODS: Twenty-four adult rabbits were randomized into three groups: 1) experimental group, 2) non-graft group, and 3) control group. The model of limb interval compression for 2 hours twice a day for 14 days was established in the experimental and non-graft group. Transplantation was performed in the experimental group and control group. Satellite cells from a half of soleus muscles in the experimental group and control group were isolated and then expanded in vitro. DAPI-tag satellite cells were transplanted back to the remaining half of the soleus muscle. The number of satellite cells with DAPI-tag was determined by fluorescence after grafts. The histological changes were compared at the time of the last compression and at the end of the 28th day after grafting. RESULTS: At the time period of 28 days following grafting of satellite cells into the soleus muscle, the satellite cells from the compressed soleus muscle increased significantly predominantly experimental group (p = 0.013), whereas those in the control group remained the same (p = 0.076). In HE staining, a large cluster of myofibers and interstitial fibers was present in compressed muscle in both the experimental group and non-graft group, while the skeletal muscle fibers and interstitial fibers were in continuity in the control group. After grafting, the muscle showed a great repair but the non-graft muscle exhibited dominant fibrosis. CONCLUSION: Autografting satellite cells by means of a small amount of expansion in vitro could improve the regenerative efficiency to repair large clusters of the damaged myofibers induced by repeated compression. CLINICAL RELEVANCE: This technique may be applicable in human compartment syndrome.

Experimental study of prognosis of chronic compartment syndrome.

There is little in the literature concerning the pathobiology and repair processes of impaired skeletal muscle after decompressive operation for chronic compartment syndrome (CCS), which would be valuable for prognosis. Repeated tourniquet compression through cuff inflation on rabbits' claves was performed daily for 2 hr, then stopped for 30 min, and applied for another 2 hr. The contralateral hindlimb, which was not compressed, served as a control. Rabbits were allocated to four groups: groups I and II were pressured with 80 and 120 mmHg for 3 days, and groups III and IV were pressured with 80 and 120 mmHg for 14 days. Skeletal muscle specimens from each group were obtained for histological and ultrastructural observation at day 1, 7, 14, and 28 post-compression. In groups I and II, a few necrotic fibers were observed and basal lamina was intact at 1 day after compression. Seven days after compression, there was an observable increase in the proliferation of satellite cells and development of myotube structures. Fourteen days after compression, regeneration of muscles was complete, and there was no significant difference compared with the control group. In groups III and IV, 1 day post-compression examination revealed a large area of necrotic fibers, fibrotic interstitium, and disintegratin basal lamina. Seven days later, proliferation of satellite cells was observed around the surviving basal lamina, and 28 days after compression we could see a large area of fibrosis. The degree of recovery of impaired muscle in rabbit's CCS-induced tissues is related to pressure and duration of compression. Complete recovery of the impaired muscle is determined by survival of basal lamina.

[Kinetic changes of canine's hindlimbs after fixation of one forelimb].

OBJECTIVE: To establish a three-foot weight-bearing canine model to imitate the biomechanical loading environment of the human's hip joint. To observe and compare the kinetic changes of hind limbs between normal and three-foot weight bearing canines. METHODS: Using 10 beagles, three-foot weight-bearing canine models were made by fixing unilateral wrist joints at 90 epsilon flexionally. The changes of ground reaction forces and the time of standing phases (Ts) of the hind limbs were compared by 3-D gait analysis pre- and postoperatively. RESULTS: Canines could walk well with three limbs after the fixation of one fore limb. However, the gait pattern changed tremendously. The canine walked jumpily by raising its head and neck, and the bilateral hind limbs kept contacting ground alternately. Ts of ipsilateral hind limb was (0.48+/-0.04)s, and Ts of contralateral hind limb was (0.46+/-0.06)s. Although, the time durations were increased a little, but there were no significant differences when compared with that of normal canines (0.43+/-0.05)s (P > 0.05). The vertical ground reaction force (Fz) of ipsilateral hind limb was (4.63+/-0.85) body weight, and the Fz of contralateral hind limb was (4.78+/-0.49) body weight. There were significant increases when compared with the Fz of normal canines (3.26+/-0.48) body weight (P < 0.05). The peak acceleration force of the ipsilateral hind limb was (0.80+/-0.30) body weight. There was significant increase compared with that of normal canines (0.72+/-0.13) body weight (P < 0.05). The peak acceleration force of the contralateral hind limbs was (0.68+/-0.22) body weight, there was no difference compared with that of normal canines (P > 0.05). The peak deceleration forces of the ipsilateral and contralateral hind limbs were--(0.26+/-0.14) body weight and--(0.13+/-0.05) body weight separately. They decreased significantly when compared with that of normal canines--(0.43+/-0.13) body weight (P < 0.05). In normal canines, the upper limbs were main load bearing limbs, they could bear 62.8%+/-2.4% of body weight. However, the hind limbs could bear only 37.2%+/-1.8% of body weight. On the contrary, in three-foot weight-bearing canines, the hind limbs became the main load bearing limbs, they could bear 59.1%+/-6.7% of body weight. CONCLUSION: Three-foot weight-bearing canine model can be used as a candidate animal model to research the effects of biomechanical loading on the progression of hip joint diseases.