Accuracy and Safety of Robot-Assisted Drilling Decompression for Osteonecrosis of the Femoral Head.

OBJECTIVE: To investigate the safety and superiority of robot-assisted femoral head drilling decompression in the treatment of femoral head necrosis. METHODS: A total of 63 patients who underwent borehole decompression of the femoral head in our hospital from January 2016 to March 2019 were recruited. Patients were divided into two groups for comparison according to surgical methods. In the robot-assisted surgery group, there were 30 cases with 41 femoral heads. The conventional group had 33 cases and 46 femoral heads. All patients signed the consent form before the operation. The follow-up time was 6 months. The incision lengths, operation times, intraoperative blood loss, intraoperative fluoroscopies, guide needle punctures, postoperative Harris scores, and postoperative complications of the two groups were compared. RESULTS: The incision length of the robot surgery group was 5.16 ± 0.41 cm, while that of the traditional surgery group was 7.42 ± 0.50 cm. The operation time of the robot surgery group was 46.99 ± 4.94 min, while that of the traditional surgery group was 55.01 ± 6.19 min. The fluoroscopy frequency of the robot surgery group was 10.50 ± 1.78 times, while that of the traditional surgery group was 17.91 ± 2.20 times. The intraoperative blood loss in the robotic surgery group was 20.62 ± 2.52 mL, while that in the conventional surgery group was 52.72 ± 3.39 mL. In the robot operation group, each femoral head guide needle was punctured three times, and the puncture was successful one time. The number of guided needle punctures in the traditional group was 8.02 ± 1.73. The difference between the two groups was statistically significant (P < 0.05). The Harris score was 69.53 ± 7.51 in the robot surgery group and 68.38 ± 7.26 in the traditional surgery group one month after surgery, 78.52 ± 6.49 in the robot surgery group and 76.41 ± 7.95 in the traditional surgery group three months after surgery, and 83.32 ± 8.62 in the robot surgery group and 81.74 ± 6.20 in the traditional surgery group six months after surgery. There was no significant difference between the two groups (P > 0.05). In the traditional group, there was one case of incision infection and one case of femoral head collapse during follow-up. In the robot group, there were no complications, such as incision infection and deep vein thrombosis. No collapse of the femoral head was found in the robot group during follow-up. CONCLUSION: The positioning system of the orthopaedic robot is an ideal method for the treatment of femoral head necrosis. This method has the advantages of simple operation, accurate drilling, a short operation time, less surgical trauma, less radioactivity, and good recovery of hip joint function.

[Preparation of chitosan/strontium-substituted hydroxyapatite films on titanium and its FTIR characteristics].

Chitosan/strontium-substituted hydroxyapatite (CHI/SrHAP) coatings were prepared on titanium substrate by electrochemical deposition technique containing Sr2+, Ca2+, PO4(3-) and Chitosan. The as-prepared coatings were examined by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) tests. The results indicate that the CHI/SrHAP coatings take the morphology of flake-like rather than the needle-like crystal , and the composite coating becomes more compact. The FTIR test indicates that the typical vibration absorption peaks of chitosan (amide I and amide II) emerged, simulated body fluid immersion test proved that the CHI/SrHAP coatings had induced carbonate-apatite formation, indicating that the composite coating possesses excellent biocompatibility. In the electrochemical corrosion testing, that the CHI/SrHAP coatings showed stronger corrosion resistance than pure Ti.

[FTIR spectra investigation of rat tissues exposure to infrared light].

Structure of biological molecules may change when exposure to electromagnetic field, the change can be recognized from the change of the infrared spectrum. The present paper studied microstructure of rat blood, testis and brain after its exposure to infrared light for 30 days via their FTIR characteristics within the 1 700 - 1 000 cm(-1) range, and the authors also analysed biological characteristics of tissue microstructure with infrared light exposure on rat by their second derivative spectra. Mechanisms of biological effects induced by infrared light were further explored through the findings. All the results indicate that the Fourier transform infrared spectroscopy can be used to analyze infrared light exposure for biological tissue microstructure.

[Preparation of fluoridated hydroxyapatite coatings on titanium by electrolytic deposition and its FTIR characteristics].

Fluoridated hydroxyapatite coatings (FHAP) were prepared on titanium substrate by electrochemical deposition technique containing Ca2+, PO4(3-), and F(-) ions. The deposition was all conducted at a constant current of 0.9 mA for 60 min at 60 degrees C. The as-prepared coatings were examined by scanning electron microscope (SEM), energy-dispersive Xray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and Xray diffraction (XRD) tests. The results indicate that the FHAP cryatals take the morphology of nanoscale-rodlike cone rather than the micron-daisy petal, and the composite coating becomes more compact. The FTIR test indicates that the symmetry of stretching and bending vibration modes of hydroxyl changed, simulated body fluid immersion test proved that the FHAP coating had induced carbonate-apatite formation, indicating that the composite coating possesses excellent biocompatibility.

[FTIR spectra investigation of rat sensitive tissues exposure to ELF-EMF].

Nonthermal effects of extremely low frequency electromagnetic fields (ELF-EMF) are related to changes in the microstructure of biological tissues after exposure to electromagnetic radiation. Fourier transform infrared spectroscopy (FTIR) analysis method can effectively study the mechanisms of biological effects of electromagnetic radiation. The present paper studies the characteristics of sensitive tissues of rat after ELF-EMF exposure. FTIR analysis of sensitive tissues of control group and experimental group showed that 50 Hz, 0.75 mT ELF-EMF exposure for 20 days can affect molecular level of the rat testis, blood and brain. Experimental results show that regular changes in absorption peak positions and intensity in the spectra of sensitive tissue may be caused by exposure to ELF-EMF, therefore, Fourier transform infrared spectroscopy is an effective means to study mechanism of biological effects of electromagnetic fields.