ABSTRACT
BACKGROUND:At present, the placement of tibial anatomic landmarks has no gold standard during total knee arthroplasty. In order to achieve the most ideal rotation function of the tibial prosthesis, we should do the preparation before surgery, understand tibial rotational alignment to rationaly select and apply the prosthesis. OBJECTIVE:To investigate the effect of tibial rotational alignment technique on patelofemoral joint biomechanics and related mechanisms. METHODS:Ten pairs of human knee joint specimens were colected to prepare experimental platform. Specimens were fixed on the experiment frame, which was fixed on the material testing instrument for mechanics experiment. Weset different knee flexion angles, including 30°, 60°, 90° and 120°. Joint replacement was performed with the knee prosthesis. Samples were randomly assigned to two groups (n=5). Tibial nodule technology and ROM technology were used to identify rotationalalignment of the tibial prosthesis. The medial and lateral patelofemoral joint contact pressure peak and patelofemoral contact area at different knee angles, and the medial and lateral parts of patelofemoral contact area at deep knee angles were observed in both groups. RESULTS AND CONCLUSION:(1) During flexion angle from 30° to 60°, the peak contact pressure of medial patelofemoral joint increased, and decreased gradualy in both groups. At flexion angle of 90°, contact pressure reached the minimum value, then increased gradualy, and reached the maximum value at 120°. No significant difference in peak contact pressure of medial patelofemoral joint at different knee angles was detected between the two groups (alP> 0.05). (2) During flexion angle from 30° to 60°, peak contact pressure of lateral patelofemoral joint decreased constantly, and then gradualy increased. No significant difference in peak contact pressure of lateral patelofemoral joint at different knee angles was detectable between thetwo groups (alP> 0.05). (3) During flexion angle from 30° to 60°, patelofemoral contact area decreased, and then increased gradualy in both groups. No significant difference in patelofemoral contact area at different knee angles was identified between the two groups (alP> 0.05). (4) At 90° and 120°, no significant difference in the area of medial and lateral contact parts was determined between the two groups (alP> 0.05). (5) Experimental results showed that tibial nodule technology and ROM technology for identifying tibial rotational alignment during total knee arthroplasty can obtain considerable biomechanical effects of patelofemoral joint.
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BACKGROUND:In the treatment of primary knee osteoarthritis, total knee arthroplasty is a common treatment, but there are some shortcomings in the traditional operation, which maylead to early failure of the prosthesis. OBJECTIVE:To explore the difference of computer-assisted total knee arthroplasty by vastus medialis approach from the traditional total knee arthroplasty. METHODS:A total of 79 patients with primary knee osteoarthritis were randomly divided into control group (41 cases) and observation group (38 cases), which underwent conventional total knee arthroplasty and computer-assisted total knee arthroplasty by vastus medialis approach. Surgical incision, operation time, total blood loss and drainage volume were recorded and compared in both groups. In 12 months of folow-up, Hospital for Special Surgery knee score was evaluated, and the complications were recorded and compared between the two groups. RESULTS AND CONCLUSION:(1) Operative incision was significantly less in the observation group than in the control group. Operation time was significantly shorter in the observation group than in the control group. Total blood loss and drainage volume were significantly lessin the observation group than in the control group (alP< 0.05). (2) Patients in both groups were folowed up for 12 months. Index score and total score of knee function were significantly higher in the observation group than in the control group (al P< 0.05). (3) No adverse events such as infection, prosthesis loosening or fracture appeared in the observation group. In the control group, four cases affected prosthesis loosening. One case suffered from wound infection. Above events were improved obviously after active treatment. No serious complications occurred. The incidence of complications was significantly lower in the observation group than in the control group (P< 0.05). (4) The results show that, compared with the traditional operation, the choice of the femoral medial approach and the use of computer aided design technology can simulate the knee replacement process, set the cutting position, improve the accuracy and success rate of surgery, have less trauma, and effectively improve knee function, and reduce the incidence of postoperative complications.
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BACKGROUND:The greatest risk of osteoporosis in total knee arthroplastyisperioperative and long-term periprosthetic fractures. However, limited by the traditional concept of osteoarthritis patientswhousualy not associated with osteoporosis, domestic clinical trials have not given enough attention to the osteoporosis before total knee arthroplasty. OBJECTIVE:To analyze the osteoporosis and its relative factors in osteoarthritis patients before total knee arthroplasty. METHODS:Data of 81 cases (81 knees) of knee osteoarthritiswhounderwenttotal knee arthroplasty in the Department of Joint Surgery of Tianjin People’s Hospital from January 2012 to November 2014 were retrospectively analyzed. They received lumbar spine and hip bone mineral density examination before surgery. The correlation of bone mineral density with age, body mass index, knee motion range,and knee deformity was analyzed before surgery. The independent risk factors for osteoporosis before replacement were analyzed. RESULTS AND CONCLUSION:(1) Of 81 patients, there were normal bone mineral density in 25 cases (31%), osteopenia in 35 cases (43%),andosteoporosis in 21 cases (26%). Al 10 males had no osteoporosis and 21 in 71 female cases suffered osteoporosis (30%). Theincidence of osteoporosis in females was significantly higher than in male patients (P=0.046). (2) There was a linear correlation of bone mineral density with age and body mass index (correlation coefficientr=-0.230, 0.225). (3) The age of≥65 years and body mass index≥25 kg/m2were independent risk factors of osteoporosis before replacement (P< 0.05). (4) Patients with knee osteoarthritis had higher incidence of osteopenia and osteoporosis before total knee arthroplasty. The degree of osteoporosis was negatively correlated with age, but positively correlated with body mass index. The age of≥65 years and body mass index < 25 kg/m2were independent risk factors for preoperative osteoporosis. Thus, bone mineral density examination is essential for those patients before total knee arthroplasty.
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BACKGROUND:Total knee arthroplasty had been generaly accepted as the final treatment plan, relieving pain and reconstructing function of knee joint. However, whether drainage tube can be used after replacement is stil controversial. OBJECTIVE:To compare the clinical effects of drainageversusnondrainage after primary unilateral total knee arthroplasty. METHODS:Total 102 patients undergoing primary unilateral total knee arthroplasty were randomly divided into 2 groups. In the drainagegroiup, a drainage tube was used. In the nondrainage group, drainage tube was not used. Total blood loss was calculated by recording the hemoglobin and hematocrit before operation and that after 1, 3, 7 days of operation. The pain visual analogue scale scores, arthrocele, ecchymosis, infection rate, and deep venous thrombosis of lower extremity were examined and analyzed postoperatively. Knee Society Scores were recorded at 1 year postoperatively. Above indexes were compared between the two groups. RESULTS AND CONCLUSION:(1) Total blood loss and blood transfusion rate were significantly higher in the drainage group than in the nondrainage group (P 0.05). (3) No significant difference in Knee Society Scores was detected between the two groups (P> 0.05). (4) Results indicated that the total blood loss and blood transfusion rate may decrease significantly in patients without wound drainage after total knee arthroplasty. Limb sweling and ecchymosis area were not increased. No significant difference in infection, deep venousthrombosis of lower extremity and knee function was detectable between the two groups. Thus, total knee arthroplasty without wound drainage is safe and does not have obvious adverse consequences.
ABSTRACT
BACKGROUND:Knee osteoarthritis is prevalent among the middle-aged and senior people in Asian countries, however, the epidemiology survey of total knee arthroplasty is rarely reported in China. OBJECTIVE: To retrospectively analyze the data of patients undergoing total knee arthroplasty from 2008 to 2013 in Hefei City, and explore the distribution of age and gender of these patients. METHODS: A retrospective analysis among patients undergoing total knee arthroplasty from January 1st 2008 to December 31st 2013 in Hefei City was performed. Data were extracted from the database of Medical Records Room of Relevant Hospitals in Hefei City, including the patient’s gender, age, disease duration, education level, body mass index and surgical site. In addition, more clinical information in one hospital were selected and analyzed, to compare the difference of clinical features between men and women. RESULTS AND CONCLUSION:From 2008 to 2013, totaly 1 146 patients underwent total knee arthroplasty due to knee osteoarthritis. The rate of total knee arthroplasty increased over the 6 years and was much higher in women than in men. The single-centre registry data revealed that there was no difference in age, disease duration, education level, and body mass index and surgical site between men and women. Our findings indicate that, the rate of total knee arthroplasty is increasing steadily from 2008 to 2013 in Hefei City and is higher in women than in men. Risk factors that account for such disparity in total knee arthroplasty utilization need to be further investigated.