ABSTRACT
BACKGROUND:In recent years,artificial cervical disc replacement surgery as a new method for the treatment of cervical disease has gradualy been accepted and understood,but relevant complications have gradualy attracted attention.OBJECTIVE:To investigate the clinical outcomes of artificial cervical disc replacement in the treatment of cervical disease and the range of motion of the replacement segment.METHODS: A total of 25 patients with artificial cervical disc replacement in the treatment of cervical spondylosis,who were treated in the Department of Orthopedics,Air Force General Hospital of Chinese PLA from August 2006 to April 2012,were enroled in this study,including 15 males and 10 females,aged 31-76 years,averagely 51.04 years.There were 6 cases of double segments and 19 cases of single segment.They were folowed up for 24 to 93 months.Clinical results were assessed using the Japanese Orthopaedic Association score,cervical dysfunction index and pain visual analog scale scores.Imaging was used to observe range of motion,cervical curvature,heterotopic ossification,and degeneration of adjacent segments.RESULTS AND CONCLUSION:Neurological function in al patients was improved to different degrees.One case suffered from mild heterotopic ossification,but no clinical symptoms were found.No significant difference in range of motion of surgical segment,and range of motion of upper and lower adjacent segments was detected between pre-replacement and final folow-up results (P＞0.05).No significant difference in range of motion of C2-C7 was found between pre-replacement and final folow-up results (P＞0.05).Japanese Orthopaedic Association score,cervical dysfunction index and pain visual analog scale scores were significantly improved during final folow-up compared with pre-replacement (P＜0.05).These results indicated that artificial cervical disc replacement in the treatment of cervical disease can achieve better clinical efficacy,can keep the range of motion of replacement segment and avoid the accelerated degeneration of adjacent segments.
ABSTRACT
BACKGROUND: Matrix material for cartilage tissue engineering exhibits too fast or too slow chondrocytes degradation in vivo, affecting tissue regeneration and shaping reconstruction, which has troubled scholars.OBJECTIVE: To amply bone marrow stromal cells (BMSCs) and induce them to chondrocytes in vitro, so as to study the feasibility of repairing articular cartilage defects in rabbits using poly(lactic-co-glycolic acid) (PLGA) loaded with BMSC-derived chondrocytes.DESIGN, TIME AND SETTING: Comparative experiment was performed at the Institute of Orthopaedics in the Fourth Military Medical University of Chinese PLA and the Center Laboratory of the Airforce General Hospital of Chinese PLA between June 2002 and June 2008.MATERIALS: A total of 36 two-month-old New Zealand white rabbits were used, and 4-6 mL bone marrow was aspirated from bilateral femoral trochanters in each animal. Primary culture and subcultures were done. In subcultures, the medium contained bone morphogenetic protein-2 (100 μg/L.), and high polymer hyaluronic acid was spread on bottom of the culture flasks in advance.In this way, the BMSCs were induced into chondrocytes and the third passage of cells at the adjusted density of 2.0×10~(10)/L wereco-cultured with PLGA for 24 hours, then PLGA-cell composites were prepared.METHODS: A defect of 4-mm in diameter and reaching medullary cavity were created in femoral condyles of 36 rabbits, and 36 right knees were treated with PLGA-cell composites, serving as experimental group, while 18 left knees with PLGA only as material group, and the other 18 knees remained untreated, as blank control group.MAIN OUTCOME MEASURES: At 4,8,12, 24 weeks after operation, the animals were euthanized and the newly formed tissues were observed macroscopically and microscopically, graded histologically, and analyzed statistically.RESULTS: Material group and blank control group shared identical outcomes of gross and histological observation, thus assigning into a control group. In the experimental group at 24 weeks, the defects were filled with white translucent cartilage tissue which appeared smooth and tenacious. The color and the luster were similar to that of normal cartilage, and was ill-demarcated from the surrounding normal cartilage. The cells on the surface paralleled to joint surface. Though the cells in the deep layer arranged disorderly, they tended to align vertically. The matrix was extensively stained. The subchondral bone formed.The tide mark basically recovered, and the new cartilage integrated with normal cartilage finely. In the control group, chondrocytes proliferated in the border, but in the bottom, there were mainly fibrous tissues. The histological grade of 12 and 24 weeks was different significantly from that of 4 and 8 weeks (P < 0.01). There were also significant differences between experimental group and control group at each time intervals after operation (P < 0.01).CONCLUSION: BMSCs were successfully induced into chondroncytes by use of bone morphogenetic protein-2 and high polymer hyaluronic acid. PLGA can be degraded and absorbed gradually while new cartilage tissues form. It can be used as a suitable scaffold material for repairing articular cartilage defects in tissue engineering.