ObjectiveTo investigate the effect of phosphorylatable short peptide (pSP) conjugated chitosan (CS) (pSP-CS) mediated insul in-l ike growth factor 1 (IGF-1) gene and human interleukin 1 receptor antagonist (IL-1Ra) gene local transfection on the repair of articular cartilage defect. MethodsCo-expression plasmid pBudCE4.1-IL-1Ra+IGF-1, single gene expression plasmid pBudCE4.1-IL-1Ra and pBudCE4.1-IGF-1 were constructed and combined with pSP-CS to form pSP-CS/ pDNA complexes. Thirty 3-month-old healthy male New Zealand white rabbits, weighing 2.0-2.5 kg, double legs were randomly divided into 5 groups (n=12). Lateral femoral condyle articular surface was only exposed in sham-operated group (group A); full-thickness cartilage defects were created in the articular surface of the lateral femoral condyle of the knee in 4 intervention groups: pSP-CS/pBudCE4.1 (group B), pSP-CS/pBudCE4.1-IL-1Ra (group C), pSP-CS/pBudCE4.1-IGF-1(group D), and pSPCS/ pBudCE4.1-IL-1Ra+IGF-1 (group E). At 1 week after operation, intra-articular injection of pSP-CS/pDNA complexes was administrated 2 times a week for 7 weeks in each intervention group, the same volume normal sal ine in group A. The general condition of animal was observed after operation, and rabbits were sacrificed at 8 weeks. Knee joint synovial fluid was collected to measure the concentrations of the IL-1Ra and IGF-1 by ELISA; mRNA expressions of Aggrecan, matrix metalloproteinase 3 (MMP-3), and MMP inhibitor 1 (TIMP-1) were detected by real-time fluorescent quantitative PCR; the chondrogenic phenotype of nascent cells in the damage zone was identified by alcian blue-periodic acid/schiff (AB-PAS) histochemistry and Aggrecan immunohistochemistry staining. ResultsThirty experimental rabbits all survived to the end of experiment, without infection and death. Large amounts of exogenous proteins of IGF-1 and IL-1Ra were detected in the synovial fluid of 4 intervention groups. There were significant differences between groups D, E and group A in IGF-1 protein expression, and between goups C, E and group A in IL-1Ra protein expression (P < 0.05). Aggrecan and TIMP-1 mRNA expressions were significantly up-regulated in group E, simultaneously MMP-3 mRNA expression was significantly down-regulated when compared with groups C and D (P < 0.05). Varying degrees of cartilage repair appeared in groups C, D, and E, showing positive staining of AB-PAS and Aggrecan, and group E had better results than groups C and D (P < 0.05); inflammatory cell infiltration and fibrous tissue prol iferation were seen in the defect region of group B, without significant cartilage repairing. ConclusionpSP-CS is an ideal gene del ivery system for cartilage defect gene therapy; IL-1Ra and IGF-1 double gene transfection has better biologic effect on cartilage defect repair.
ObjectiveTo evaluate the effectiveness of anatomic femoral component prosthesis for severe development dysplasia of the hip (DDH) in total hip arthroplasty (THA). MethodsBetween September 2009 and September 2013, 48 patients (51 hips) with severe DDH underwent THA with cementless anatomic femoral component prosthesis. There were 5 males (5 hips) and 43 females (46 hips) with an average age of 51 years (range, 28-67 years). The left hip was involved in 25 cases, the right hip in 20 cases, and bilateral hips in 3 cases. There were 39 cases (44 hips) of Crowe type Ⅲ and 9 cases (7 hips) of Crowe type ⅠV. The visual analogue scale (VAS) score was 5.72±1.84, and Harris score was 41.66±4.87 at preoperation. All patients had leg discrepancy with a length difference of (4.31±0.84) cm. ResultsThe duration of surgery was 59-110 minutes (mean, 78.6 minutes), and the hospitalization days were 6-20 days (mean, 12.3 days). All patients obtained primary healing of incision without wound related complications of swelling, effusion, and infection. Two patients were found to have intramuscular venous thrombosis. All patients were followed up 10-54 months (mean, 29 months). Limp was observed at the early stage after operation in 9 patients and disappeared after 1 year, the other patients had normal gait. The VAS score 1.46±0.47, Harris score 88.66±3.48, and the leg length difference (1.15±0.33) cm at last follow-up all showed significant differences when compared with the preoperative values (P<0.05). No prosthesis loosening or subsidence, heterotopic ossification, dislocation, and infection occurred. ConclusionAnatomic femoral component prosthesis for severe DDH in THA can relieve pain, and improve the hip joint function and limb discrepancy. Short-term effectiveness was satisfactory, but the long-term effectiveness should still be observed in future.