ABSTRACT
BACKGROUND: The femoral intramedul ary guides in total knee arthroplasty require high precision, complex operation, it is very important for prosthesis and joint function to choose more precise positioning method and determine the correct needle point. OBJECTIVE: To study the effect of needle point position on prosthesis arrangement when applying different femoral intramedul ary guides methods in total knee arthroplasty. METHODS: Total y 80 patients who received the treatment of total knee arthroplasty in Changshu No.1 People’s Hospital from January 2012 to July 2015 were selected and divided into test and control groups according to random number table (n=40/group). The patients in the test group accepted CT scan for femoral intramedul ary guides. The theoretical position of femoral intramedul ary guides entry point was marked using radiographic parameters. In the control group, the traditional total knee arthroplasty technology was used to mark the entry point of femoral intramedul ary guides. The needle point position when applying different femoral intramedul ary guide methods was observed. The effect of femoral intramedul ary guides on prosthesis arrangement in total knee arthroplasty was discussed. RESULTS AND CONCLUSION: Compared with the control group, the distance from entry point to femoral anatomic line on positive and lateral X-ray film in the test group was shorter, femoral prosthesis lateral angle and physiological valgus angle were closer to the theoretical value, distance from intersection of femur axis and femoral condyle to block center was shorter; the differences were statistical y significant (P < 0.05). These results demonstrate that compared with the traditional two-dimensional intramedul ary positioning, the needle point position of three-dimensional CT scan stimulative positioning is more accurate. The location more concentrates on within intercondylar fossa 2-5 mm, more front of intercondylar fossa 3-10 mm, three-dimensional CT scan stimulative positioning is a reliable choice for femoral intramedul ary guides.
ABSTRACT
BACKGROUND:Total knee arthroplasty mainly used fixed platform, but more and more movable platform was selected year by year in the clinic. Rotary platform theoretical y can apparently improve the curative effects, but it has not been verified in the clinic. OBJECTIVE:To summarize the design characteristics and clinical results of Gemini MKII (Link, Germany) rotary platform. METHODS:From January 2004 to January 2009, 108 patients (119 knees) including 31 males and 77 females were treated with total knee arthroplasty by using Gemini MKII system. There were 97 unilateral cases and 11 bilateral cases at the first stage of replacement. Preoperative diagnosis:1 case of hemophilic arthritis, 1 case of venereal Charcot’s disease, 8 cases of post-traumatic arthritis, 11 cases of rheumatoid arthritis, and 87 cases of degenerative osteoarthritis. The prosthesis was fixed with bone cement. None received patel ar replacement. RESULTS AND CONCLUSION:None experienced infection, femoral condyle fracture or nerve and vascular damage. Except bilateral replacement, the average operation time of unilateral replacement was (56±13) minutes. Average postoperative hemoglobin decreased (25±5) g/L. After replacement, hemoglobin maintained over 100 g/L in 83 patients (86%), without blood transfusion. Knee joint score and function score recovered to (92.0±4.7) points and (90.3±6.8) points at half years after replacement, and became (94.4±3.2) points and (91.6±5.9) points during final fol ow-up, which was significantly improved as compared with that pre-replacement (P<0.01). No revision surgery should be done for lining prolapse or spin out, osteolysis and prosthesis loosening. These results indicated that the early and midterm results of Gemini MKII rotating-platform prosthesis were satisfactory, but the long-term results remain to be confirmed.