The injury of the knee joint is usually accompanied with the generation of hydrops. The volume of hydrops can be used as a reference to evaluate the extent of knee joint injuries. Based on the principle of bioimpedance detection, in this paper, a new method is proposed to detect knee joint hydrops. Firstly, a three-dimensional model of the knee joint was established according to the physiological and anatomical structure of the knee joint. Secondly, a knee impedance detection system was constructed based on the four-electrode theory, and the relationship between the knee impedance change and the volume of hydrops was calculated by linear regression. Finally, the model of rat knee joint hydrops was established, and the knee joint impedance was measured under different hydrops content to deduce the relationship between the fluid content and the knee joint impedance. The fluid volume in the joint was calculated by measuring the knee joint impedance, and the error rate was less than 10%. The experimental results show that the method proposed in this paper can establish the relationship between the impedance of the knee and the volume of fluid and realize the detection of the fluid volume.
ObjectiveTo compare the patient-reported outcomes regarding function, joint amnesia, and the quality of life after unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). Methods The clinical data of patients who received UKA or TKA between September 2017 and June 2018 were retrospectively analyzed. After propensity score matching, 40 patients (40 knees) each in TKA group and UKA group were finally included in the study. There was no significant difference between the two groups in gender, age, body mass index, surgical side, preoperative knee range of motion, Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score, clinical and function scores of knee society score (KSS) (P>0.05). At 2 years after operation, WOMAC score, KSS clinical and function scores were performed on the two groups of patients, and compared with preoperative ones; knee injury and osteoarthritis outcome score-physical function short form (KOOS-PS), short-form 36 health survey scale (SF-36 scale), and forgotten joint score (FJS) were also performed. Results At 2 years after operation, the total score of WOMAC, the clinical and function scores of KSS in the two groups significantly improved when compared with preoperative ones (P<0.05), but there was no significant difference in the total score of WOMAC, the individual score of WOMAC, the clinical and function scores of KSS between the two groups (P>0.05). The total KOOS-PS score in the UKA group was significantly lower than that in the TKA group (t=4.243, P=0.000), and the scores of writhing/knee rotation, kneeling, and squatting in the UKA group were significantly lower than those in the TKA group (P<0.05). The total FJS score in the UKA group was significantly higher than that in the TKA group (t=−6.334, P=0.000). In the UKA group, the scores of 7 items were significantly lower than those of the TKA group (P<0.05) including when walking over 15 minutes, when climbing stairs, when walking on uneven ground, when standing for long periods, when doing housework or gardening, when taking a walk or hiking, and when doing your favorite sport. The SF-36 scales of physiological function, energy, social function, emotional function, and mental health in the UKA group were significantly higher than those in the TKA group (P<0.05). Conclusion Compared with TKA, patients treated with UKA may have better knee function recovery, joint amnesia, and higher quality of life.
A software and hardware platform for gait simulation and system evaluation for lower limb intelligent prosthesis is proposed and designed, in order that the wearable symmetry effect of the intelligent knee prosthesis can be quantitatively analyzed by machine test instead of human wear test. The whole-body three-dimensional gait and motion analysis system instrument, a device to collect gait data such as joint angle and stride of adults, was used for extracting simulated gait characteristic curve. Then, the gait curve was fitted based on the corresponding joint to verify the feasibility of the test platform in the experiment. Finally, the developed artificial knee prosthesis was worn on the prosthetic evaluation system to quantitatively analyze the gait symmetry effect. The results showed that there was no significant difference in gait symmetry between the developed knee joints at different speeds, which could reach more than 88%. The simulation and evaluation of the prosthetic gait have good effects on the functional simulation and evaluation of the lower limb intelligent prosthesis.
摘要:目的:探讨地震伤员中膝关节损伤的机制、类型及处理方法。 方法:对我院收入住院的2728例 5·12汶川特大地震伤员伤情特点进行分析,筛选出有膝关节损伤的病例进行分析。 结果: 膝关节损伤前三位分别是髌骨骨折(42.15%)、胫骨平台骨折(21.05%)、股骨髁骨折(13.16%),这与人们在地震时奔跑摔伤以及被房屋倒塌砸伤有很大关系。结论:地震后膝关节损伤其发病率、受伤机制、损伤类型、合并伤情况及治疗处理均有其特点,总结这些特点和规律将对地震伤膝关节损伤患者的处理产生积极作用。Abstract: Objective: To investigate the knee joint injury mechanisms, types and treatment of the earthquake wounded. Methods: Analysis the characteristics of the 2728 cases of West China Hospital from 5.12 Wenchuan earthquake wound, screen out the cases of knee joint injury. Results: Patellar fracture (42.15%),tibial plateau fracture(21.05%), femoral condyle fracture (13.16%), were the top three of knee joint injuries, which have a great relationship with falling down and (or) injured by collapsed houses when people were running in the earthquake. Conclusion: After the earthquake the knee joint damages its disease incidence rate, is injured the mechanism, the damage type, the merge wound situation and treatment processing has its characteristic, will summarize these characteristics and the rule damages patient’s processing to the earthquake wound knee joint to have the positive role.
Objective To evaluate the surgical skill, cause of revision, compl ications, prosthetic survival and postoperative function in revision of custom-made tumor prosthesis replacement of knee joint. Methods The cl inical data of 33 patients who received prosthetic revision surgery between June 2002 and June 2007 were reviewed. There were 17 malesand 16 females with an average age of 33.1 years (range, 16-67 years). The pathological diagnosis included 17 osteosarcomas, 11 giant cell tumors, 2 mal ignant fibrous histocytomas, 1 chondrosarcoma, 1 synovial sarcoma, and 1 l iposarcoma. The involved locations were distal femur in 22 cases and proximal tibia in 11 cases. The average interval between first prosthetic replacement and revision surgery was 45.3 months (range, 6-180 months). The reason for revision included local recurrence in 2 cases, deep infection in 8 cases, aseptic loosening in 7 cases, peri prosthetic fracture in 1 case, prosthetic stem fracture in 6 cases, and prosthetic hinge failure in 9 cases. Six patients with deep infection received two-stage revision surgery, while the other 27 patients received one-stage revision. Cemented prostheses were used in all patients. Allograft prosthetic composite and revisions were used in 2 patients who had deficit of diaphysis for stem fixation. Results In 17 patients who received both primary prosthetic replacement and revision, the operative time was (149.8 ± 40.5) minutes and (189.9 ± 43.8) minutes, and the blood loss was (605.2 ± 308.0) mL and (834.1 ± 429.9) mL for primary prosthetic replacement and revision, respectively; all showing statistically significant differences (P lt; 0.05). The mean time of follow-up was 45.1 months (range, 12-76 months). Heal ing between allograft and host bone was obtained in 2 patients with allograft prosthetic composite and revision after 1.5 years and 2 years, respectively. After revision surgery, 3 patients died of lung metastasis after 12-24 months, and other 3 patients havinglung metastasis were al ive with disease. Nine (30%) compl ications occurred in 30 patients who were al ive at last follow-up. The compl ications included wound infection in 2 patients, deep infection in 5 patients, mechanical problems in 2 patients. Prosthetic failure occurred in 7 patients (23.3%). The 5-year survival rate of revised prosthesis was 68.6%. The Musculoskeletal Tumor Society (MSTS) score at 6 months after revision (73.6% ± 14.4%) was significantly improved (P lt; 0.01) when compared with before revision (57.1% ± 10.6%). Conclusion The main reasons for revision of custom-made tumor prosthesis of knee joint were mechanical problems and deep infection. Although revision surgery of knee is relatively compl icated and has some compl ications, a functional l imb could be maintained in most tumor patients.
Objective To investigate the surgical planning and the mid-term effectiveness of four major lower extremity arthroplasties (4JA) in patients with rheumatoid arthritis (RA). Methods A clinical data of 25 patients with RA, who received 4JA and were followed up more than 3 years between June 2012 and September 2018, was retrospectively analyzed. There were 3 males and 22 females, with an average age of 48.6 years (range, 27-80 years). The body mass index ranged from 16.0 to 28.4 kg/m2, with an average of 20.48 kg/m2. The duration of RA ranged from 2 to 35 years (median, 21 years). There were 8 cases (12 sides) of knee valgus, 6 cases (12 side) of acetabular retraction, and 5 cases (10 sides) of hip stiffness. Among them, 20 patients underwent hip surgery first, and 5 patients underwent knee surgery first. Hip joint function was evaluated by Harris score, Hip Disability and Osteoarthritis Outcome Score (HOOS), hip range of motion, and Trendelenburg sign; knee joint function was evaluated by American Hospital for Special Surgery (HSS) score, knee range of motion and muscle strength, and a timed up and go (TUG) test was performed at last follow-up. X-ray films were used to observe whether the prosthesis was loose or displaced. Results All 25 patients completed 4JA. Only 1 patient (1 side) had incision infection after operation, 3 patients (3 sides) had proximal femur fractures during operation. All patients were followed up 3.0-8.8 years, with an average of 5.8 years. At last follow-up, the Harris score, HOOS score, and range of motion of flexion, extension, and abduction of the hip joint significantly improved when compared with those before operation, and the patients with positive Trendelenburg sign decreased. The HSS score and range of motion of flexion and extension of the knee joint also significantly improved when compared with those before operation. There were significant differences in all indexes between pre- and post-operation (P<0.05). The muscle strength was grade V. The TUG test ranged from 7.8 to 15.34 seconds (mean,10.79 seconds). X-ray films showed the prosthesis was not loose or displaced. Conclusion When RA patients receive 4JA, adequate preoperative evaluation, rational selection of the timing and sequence of surgery, and maximal restoration of lower limb alignment can achieve good mid-term effectiveness.
OBJECTIVE: Extension stiffness of knee joint is always treated by the quadricepsplasty, but the main deficiency of this method is that patient feels weakness of lower limb and easily kneels down. The aim of this article is to explore the method to resolve the complications after quadricepsplasty. METHODS: Since 1978 to 1997, on the basis of traditional procedures of quadricepsplasty, sartorius muscle was used to reinforce the extension of knee joint. The lower 2/3 of sartorius muscle was fully dissociated only with its insertion intact. A tendon-periosteal-bone flap, about 2 cm in width, was managed on the anterior surface of patella, with its pedicle on the medial edge of patella. The tendon-periosteal-bone flap was used to fix the dissociated sartorious into patella to reinforce the extension of knee joint. The very lower part of sartorius was mainly aponeurosis, with the help of an aponeurosis bundle of iliotibial tract, it was fixed into the insertion of patellar ligament, through a bony tunnel chiseled adjacent to the insertion of patellar ligament. By now the movement of knee joint extension was strengthened by the transferred sartorius muscle. Postoperatively, every patient was required to extend and flex knee joint actively and/or passively. Altogether 12 patients were treated, 9 of them were followed up with an average of 14 months. RESULTS: The average movement was increased from 15 degrees to 102 degrees, and the average myodynamia was improved from grade II to grade IV. CONCLUSION: Traditional quadricepsplasty co-operated with transfer of sartorius muscle can strengthen the myodynamia of knee joint extension. It is simple method and can really achieve good function.
This article introduces the basic principles of finite element analysis in biomechanics, focusing on the basic principles of a variety of finite element analysis software, and their respective characteristics. In addition, it also describes the basic stress analysis of UGNX6.0 NASTRAN analysis for artificial knee process, i.e. the choice of the type, material definition, the set of constants, finite element mesh division and the finite element results of the analysis. Finite element analysis and evaluation of the design of personalized artificial knee were carried out, so that the rationality of the geometric design of the structure of the experimental design of artificial knee has been verified.
ObjectiveTo investigate the effect of body mass index (BMI) on the short- and medium-term effectiveness of unicompartmental knee arthroplasty (UKA) in the treatment of anterior medial compartmental osteoarthritis of knee joint.MethodsThe clinical data of 55 patients (61 knees) with anterior medial compartmental osteoarthritis of knee joint treated with minimally invasive UKA between May 2014 and May 2019 were retrospectively analyzed. According to BMI, the patients were divided into 3 groups: normal body mass group [group A, BMI 18.50-24.99 kg/m2, 23 cases (25 knees)], overweight group [group B, BMI 25.00-29.99 kg/m2, 23 cases (25 knees)], obesity group [group C, BMI 30.00-39.99 kg/m2, 9 cases (11 knees)]. There was no significant difference in gender, age, sides, disease duration, and preoperative American Special Surgery Hospital (HSS) score, pain visual analogue scale (VAS) score, and knee range of motion (ROM) among 3 groups (P>0.05). The operation time, intraoperative dominant blood loss, and the postoperative decreased amount of hemoglobin at 1 week were recorded and compared among 3 groups. The HSS score, VAS score, and ROM were used to evaluate the knee function and pain improvement.ResultsThere was no significant difference in the operation time, the intraoperative dominant blood loss, and the postoperative decreased amount of hemoglobin at 1 week among 3 groups (P>0.05). All the 55 patients were followed up 5-60 months, with an average of 24 months. No complication such as infection, fat embolism, or deep venous thrombosis of lower extremity occurred after operation. The anteroposterior and lateral X-ray films of the knee joint showed that no dislocation or loosening of the prosthesis occurred and the position of the prosthesis was good. At last follow-up, the HSS score, VAS score, and ROM of the 3 groups were significantly improved when compared with preoperative ones (P<0.05); but there was no significant difference among 3 groups (P>0.05).ConclusionFor obese and overweight patients with anterior medial compartmental osteoarthritis of the knee joint, the use of minimally invasive UKA can achieve satisfactory short- and medium-term effectiveness, and the long-term effectiveness needs further follow-up.
Objective To analyze the correlation between the morphology of tibial intercondylar eminence and non-contact anterior cruciate ligament (ACL) injury, and provide a theoretical basis for the prevention and risk identification of ACL injury. Methods A retrospective analysis was conducted on the knee radiographs of 401 patients admitted to the Chengdu Second People’s Hospital between January 2017 and October 2021, including 219 males and 182 females. Non-contact rupture of ACL was observed in 180 patients and confirmed by arthroscopy or surgery, while the remained 221 patients were confirmed to have normal ACL by physical examination and MRI. The heights of medial and lateral tibial intercondylar eminence and the width of tibial intercondylar eminence of the 401 patients were measured, and the risk factors of ACL injury were analyzed. Results The height of medial tibial intercondylar eminence was lower and the width of tibial intercondylar eminence was smaller in male patients with ACL fracture than those in the male control group with statistical significance (P<0.05). Logistic regression analysis showed that a narrow width of tibial intercondylar eminence was a risk factor of ACL injury in males (P<0.05). The receiver operating characteristic (ROC) curve showed that the diagnostic threshold was 11.40 mm, the area under the curve (AUC) was 0.851 [95% confidence interval (CI) (0.797, 0.896)], the sensitivity was 72.81%, and the specificity was 84.76%. The height of medial tibial intercondylar eminence was lower and the width of tibial intercondylar eminence was smaller in female patients than those in the female control group with statistical significance (P<0.05). Logistic regression analysis showed that both a low height of medial tibial intercondylar eminence and a narrow width of tibial intercondylar eminence were risk factors of ACL injury in females (P<0.05). For the width of medial tibial intercondylar eminence, the ROC curve showed that the diagnostic threshold was 8.30 mm, and the AUC was 0.684 [95%CI (0.611, 0.751)], the sensitivity and specificity were 63.64% and 72.41%, respectively; for the height of medial tibial intercondylar eminence, the diagnostic threshold was 11.30 mm, and the AUC was 0.699 [95%CI (0.627, 0.756)], the sensitivity was 89.39%, and the specificity was 47.41%. Conclusions The reduced width of tibial intercondylar eminence is a risk factor and effective predictor of non-contact ACL injury in males. Both the reduced height of the medial tibial intercondylar eminence and the reduced width of tibial intercondylar eminence are risk factors and may be predictors for non-contact ACL injury in females.