[Correlation between spatial inclination of Blumensaat line and anterior cruciate ligament injury based on EOS biplanar 3D imaging system].

OBJECTIVE: To explore correlation between femoral mechanical axis and Blumensaat line (FMBL) angle of knee joint (angle between Blumensaat line and femoral mechanical axis), α angle (angle between Blumensaat line and axis of distal femur in sagittal plane) on EOS biplane imaging and non-contact anterior cruciate ligament(ACL) injury, and evaluate angle for its accuracy in predicting the populations prone to non-contact ACL injury. METHODS: From February 2018 to October 2020, EOS imaging and clinical data from 88 patients (176 knees) with unilateral non-contact ACL injury were retrospectively analyzed, including 53 males and 35 females, aged from 18 to 45 years old with an average of (30.3±6.2) years old, 48 patients on the left side and 40 patients on the right side. The patients were divided into ACL-affected group and ACL-health group according to side of ACL injuries, and 51 patients (51 knees) with non-ACL identified from EOS database were included in normal control group, including 28 males and 23 females, aged from 20 to 44 years old with an average of (31.6±5.5) years old, 26 patients on the left side and 25 patients on the right side. Full-length EOS imaging of skeleton extremitatis inferioris among three groups were reconstructed to 3D images of skeletal system with EOS software, and then FMBL angle and α angle were measured on the images. Univariate binary Logistic regression analysis was performed to determine the influence of the univariate(FMBL angle or α angle) on ACL status(normal or torn). And the angle cutoff value for univariate was selected based on receiver operating characteristics curve (ROC) to got the best accuracy. RESULTS: There was no statistically significant difference in age, gender and side distribution between ACL-injured group and normal control group(P>0.05). Statistical analyses (one-way ANOVA) indicated no significant difference in FMBL angle between ACL-injured knee group (32.8±2.3)° and ACL-injured contralateral knee group(32.5±2.3)°(P>0.05), but the values between two groups were significantly lower than that in normal control group (37.0±2.0)°(P<0.001). There was no statistically significant difference in α angle among three groups (P>0.05). Univariate binary Logistic regression analysis demonstrated that FMBL angle was risk factor for non-contact ACL injury[OR=0.433, 95%CI(0.330, 0.569), P<0.001]. The area under ROC curve for FMBL angle was 0.909[95%CI(0.861, 0.958), P<0.001], and the sensitivity and specificity were 70.5% and 98.0% respectively, cut-off value was 33.7°. CONCLUSION: FMBL angle formed by Blumensaat line and femoral mechanical axis is one of the risk factors for non-contact ACL injury and has good predictive accuracy. The general population with FMBL angle below 33.7° may be increased risk for ACL injury.

Factors influencing cognitive reactivity among young adults at high risk for depression in China: a cross-sectional study.

BACKGROUND: Understanding the factors influencing cognitive reactivity (CR) may help identify individuals at risk for first episode depression and relapse and facilitate routine access to preventative treatments. However, few studies have examined the relationship between CR and depression in Asian countries. This study was performed to assess the current status of CR among Chinese young adults and explore influencing factors. METHODS: A national cross-sectional online study using convenience sampling was conducted among 1597 healthy young adults in China (response rate: 93.94%) with a mean age of 24.34 (SD = 5.76) years. RESULTS: The mean CR score was 51.36 ± 18.97 (range 0-130). Binary logistic regression showed that a low level of CR was associated with the following factors: high self-compassion, high social support, high resilience, high monthly household income, and living in a rural area, with odds ratios (ORs) ranging from 0.14 to 0.70. Young adults in full-time employment, experiencing poor sleep, with high neuroticism, who reported frequent sad mood, and who had a high intensity of negative life events had increased CR to depression, with ORs ranging from 1.18 to 6.66. The prediction probability of these factors was 75.40%. Causal relationships among the influencing factors and CR could not be explored. CONCLUSIONS: The self-reported CR levels among Chinese young adults were moderate. Enhancing self-compassion, resilience, and social support for young adults and reducing negative life events, neuroticism, and poor sleep may help decrease CR. These findings may help healthcare providers or researchers determine how to cultivate and improve the CR of young adults by establishing documented policies and/or improving intervention efficacies.

[Effect of pelvic rotation on the placement angle of acetabular prosthesis in total hip arthroplasty].

OBJECTIVE: To study the effect of pelvic rotation in three-dimensional direction on the actual placement angle of acetabular prosthesis in total hip arthroplasty. METHODS: Pelvic CT imaging data of normal adults were collected, and three-dimensional reconstruction of pelvic acetabulum was performed with computer software to simulate the rotation of the pelvis around X, Y and Z axes perpendicular to the sagittal, transverse and coronal planes of the human body. Radiographic inclination(RI) and radiographic anteversion (RA) of the acetabular cup were measured when the acetabular prosthesis was implanted at a standard angle. The correlation analysis was used to quantify the relationship between the rotation angle of each axis and the actual angle of acetabulum. RESULTS: The pelvic rotation along the X-axis and Y-axis had little effect on the RA of the acetabulum, but had a great influence on the RI and showed a linear correlation. The regression equations were RA=0.682 4X+10.256(r²=0.308 4) and RA=-0.714 1Y+10.424(r²=0.999 8). The pelvic rotation along the Z-axis had little effect on the RA, but had a linear correlation with the RI, and the regression equation was RI=1.0Z+46(r²=1.0). CONCLUSIONS: The anteroposterior rotation of the pelvis or the longitudinal rotation along the body significantly affected the acetabular anteversion, but had little effect on the abduction angle. On the contrary, the left and right deviation of the pelvis on the coronal plane could significantly affect the acetabular anteversion angle, but did not affect its anteversion angle.

[Introduction of EOS imaging system and its current research status in evaluating clinical value of lower limb force line].

The principle and technical background of EOS imaging system are introduced. Combining with the publicity of this technology and the existing literature reports, it is known that low dose EOS technology can reduce radiation dose by 5 to 10 times in the course of examination, and micro dose EOS can even reduce radiation dose by 45 times. The image quality is only high or low; the system has EOS 2D and 3D workstations, which can help clinicians to measure and evaluate coronal and sagittal force lines of lower limbs easily. The tilt and torsion of limbs can be measured three-dimensional after three-dimensional model reconstruction in the three-dimensional workstation. Using these results, preoperative evaluation can be carried out. It is helpful for clinicians to evaluate and improve preoperative planning and post-operative measurement and evaluation of surgical effect. In terms of measurement accuracy, a large number of literatures reported that the accuracy of EOS 2D measurement is comparable to that of general radiology measurement, while the accuracy of EOS 3D reconstruction measurement is comparable to that of CT and MRI. Based on the technical characteristics and advantages of EOS, this paper reviews the literature reports and research progress of EOS in evaluating the accuracy of lower limb alignment.

Patterns of Compartment Involvement in End-stage Knee Osteoarthritis in a Chinese Orthopedic Center: Implications for Implant Choice.

OBJECTIVES: Knee osteoarthritis (OA) is a prevalent disease in the elderly, causing pain and contributing to poor quality of life. Surgical intervention, such as knee arthroplasty, can be used in those with end-stage knee OA. Total knee arthroplasty (TKA) is one of the most common surgical procedures for end-stage knee OA, with promising clinical outcomes. However, a large proportion of patients with isolated compartment OA can be treated with unicompartmental knee arthroplasty (UKA) instead. UKA has shown better patient-reported functional outcomes, and lower mortality and major complication rates than TKA. The percentage of UKA in knee arthroplasty varied in different orthopedic centers, and we believed that the requirement for UKA was underestimated in many centers. A retrospective study was carried out on our Chinese patient population presenting for knee arthroplasty; it aimed to identify the proportion of patients that might be suitable for UKA. METHODS: A retrospective cross-sectional study of 155 consecutive patients (168 knees) awaiting TKA for end-stage primary OA was performed. The pattern and grade of OA was recorded from preoperative weight-bearing anteroposterior and non-weight-bearing lateral radiographs. The medial, lateral, patellofemoral compartment was given an individual Kellgren-Lawrence grade on the radiographs, and those grade ≥3 were defined as end-stage OA. The compartments involvement was established then. The integrity of the anterior cruciate ligament (ACL) was determined by the modified Keyes classification on lateral radiographs. The applicability for total or partial knee arthroplasty was determined according to the compartments involvement. RESULTS: Medial compartment involvement was found in 154 (91.7%) knees, while the involvement of the lateral compartment and patellofemoral joint was found in 54 (32.1%) and 57 (33.9%) knees, respectively. Eighty-one (48.2%) of the knees showed medial compartment OA with or without patellofemoral joint involvement, and modified Keyes classification grade 1, indicating an intact ACL, and, hence, potential suitability for medial UKA. Isolated lateral OA indicating possible suitability for lateral UKA was identified in 11 knees (6.5%). No patients showed isolated patellofemoral joint OA. The other 76 (45.2%) knees could be treated by TKA. CONCLUSIONS: The medial compartment was the most commonly affected in our Chinese patients indicated for knee arthroplasty. More than half of the patients in this group could be treated by either medial or lateral UKA.

Characteristics of sagittal spine-pelvis-leg alignment in patients with severe hip osteoarthritis.

PURPOSE: The interaction between the sagittal alignment of the spine and pelvis and the compensatory mechanism in patients suffering from spinal disorders has been well documented. However, in patients with hip osteoarthritis (HOA), few studies have explored how the hip joint pathology could affect the sagittal alignment of the hip, pelvis and spine, and no reports have investigated whether these changes are involved in the pathogenesis of low back pain in these patients. The aims of this case-control study were to investigate the sagittal spine-pelvis-leg alignment in patients suffering from severe HOA and to understand whether the alignment was related to the occurrence of low back pain and the health-related quality of life in these patients. METHODS: Fifty-eight patients with severe HOA and 64 asymptomatic controls were studied. Digital lateral X-rays of the spine, pelvis and proximal femur were obtained with the patients placed in upright positions. The following radiographic parameters were measured to examine the sagittal alignment of the pelvis, hip and spine: pelvic incidence (PI), pelvic tilting (PT), sacral slope (SS), pelvic femoral angle (PFA), femoral inclination (FI), lumbar lordosis (LL), spino-sacral angle (SSA), C7 tilt (C7T) and T1 spinal-pelvic inclination (T1-SPI). The global balance patterns of spinal-pelvic alignment were classified as normal balance, slight unbalance and severe unbalance according to the relative position of the C7 plumb line to the sacrum and femoral heads. Short Form-36 questionnaire was carried out in the patients. Comparisons were carried out between the patients with HOA and the controls and between the HOA patients with or without low back pain. Correlation analysis was used to measure relationships between the HOA patients' parameters. RESULTS: There were no significant differences in the age and gender distribution between the HOA patients and control. Compared with the controls, the patients with HOA showed significantly higher SS and lower PT, similar PI in the pelvis, significantly smaller C7T, larger T1-SPI but comparable LL and SSA in the spine, and significantly smaller PFA but larger FI in the hip joint. In addition, the patients with HOA had a significantly greater incidence of severe unbalanced spinal-pelvic alignment than did the controls (22.4 vs 3.1 %, respectively). In patients with HOA, the PFA was significantly correlated with SS, SSA and FI but not with PI, LL or C7T; while the physical component score of short form-36 was significantly correlated with T1-SPI, C7T and FI. A comparison between the HOA patients with or without low back pain, however, showed no significant differences in the radiographic parameters, global sagittal balance patterns and Short Form-36. CONCLUSIONS: The sagittal morphology of the pelvis in patients with severe HOA was normal and might not be involved in the development and progression of this disorder. Although the whole spine was involved in compensating for the flexed hip joint, the poor ability resulted in severely unbalanced spinal-pelvic alignment in these patients. The forward inclined spine and retroverted femur would contribute to the poor physical activities in these patients. However, the abnormal sagittal spine-pelvis-leg alignment in patients with severe HOA might not be involved in the pathogenesis of low back pain.

[Revision total hip arthroplasty using a cementless prosthesis].

OBJECTIVE: To assess the operative technique and results with the usage of cementless prosthesis in hip revision. METHODS: Retrospective study was done on revision of total hip arthroplasty with cementless prosthesis in 72 patients (41 males and 31 females) with an average age of 65.7 years (28-82 years) from January 2004 to December 2009. The reason for revision was 2 infection, 54 aseptic loosening, 4 periprosthetic fractures, 5 fracture of femoral stems and 7 cases of acetabular abrasion after hemi-arthroplasty. The operation time, bleeding loss, complications of infection, dislocation, periprosthetic fractures and loosening were evaluated. The Harris score were used for hip function evaluation. RESULTS: The average operation time was (146±47) minutes (70-280 minutes) and bleeding loss during the operation was (970±540) ml (200-2500 ml). Bacterium cultivation during operation demonstrated infection in 2 patients. Bone windows at the lateral femoral were opened in 4 patients and extend trochanteric osteotomy was done in 7 patients. Fracture of the proximal femur occurred in 8 cases. Twenty-nine patients were treated with bone graft including 18 autografts and 11 allografts. Sixty-seven patients were followed up for an average time of 66 months (20-92 months). Additional revisions were performed in 3 cases including 2 dislocations and 1 infection. There were no death, no damage of major blood vessels and nerves. The bone graft healed during 3-5 months. The survival rates of the femoral prosthesis and the acetabulum prostheses were 95.5% and 98.4%. The mean Harris score was 86±8 (55-95 points). Osteolysis were seen in 13 hips but migration was seen in only 1 patient. CONCLUSIONS: The cementless prosthesis is useful in revision total hip arthroplasty and the perfect clinical results are related to the reliable primary fixation.

[Preoperative analgesia in orthopaedic surgery].

Orthopaedic postoperative pain not only brings a lot of side effects to patients, but also directly affects early rehabilitation after surgery. Effective preoperative pain management mainly includes three-stage individual pattern analgesia, which refers to preoperative, intraoperative and postoperative analgesia. The purpose is to reduce pain in multiple planes and three-dimension, strengthen the effect of analgesics and reduce dosage and side effect of single drug. This paper summaries new progress on individual-multiple-pattern analgesics, pain assessment method and various therapies.

[Metaphase outcome of total hip arthroplasty with Zweymuller system in treating developmental dysplasia of the hip].

OBJECTIVE: To analyze the metaphase outcome of total hip arthroplasty with Zweymuller system and deepening acetabulum technique in treating DDH. METHODS: From Jan.1998 to Dec. 2004,56 patients (62 hips) with DDH (secondary osteoarthritis) were treated with total hip arthroplasty with Zweymuller system. There were 14 males (15 hips) and 42 females (47 hips) with an average age of 48.6 years,ranged from 30 to 67 years. All patients had pain of hip joint and functional disturbance before operation. Observation items included postoperative complications,imaging and function of hip joint. The function of hip joint was analyzed according to Harris scoring. RESULTS: All patients were followed up from 5 to 11 years with an average of 6.5 years. X-rays showed that the acetabular cup was in the position of true acetabulum, which combined tightly with the peripheral bone, the abduction angle of the acetabular cup was from 35 degrees to 45 degrees, introversion and extroversion of the femoral prosthesis was within 3 degrees, operated legs were shorter with a mean of (0.5 +/- 0.2) cm. The complications were as following:deep vein thrombosis in 20 cases,which were improved after thrombolysis;hip dislocation in 1 case,which was treated with reduction and immobilization for 3 weeks; ectopic ossification in 4 patients,all were Brook II type; no found infection or nerve injury. The Harris scoring was 87.4 +/- 3.5 postoperative,which was significant higher than that preoperative (43.2 +/- 6.7). CONCLUSION: The metaphase outcome of total hip arthroplasty with Zweymuller system and deepening acetabulum technique in treating DDH can obtain good result.

[Preliminary clinical outcome of domestic posterior-stabilized total knee arthroplasty].

OBJECTIVE: Total knee arthroplasty (TKA) has been widely used in China. More and more attentions are paid to the development of knee prosthesis that fit for the anatomy of Chinese knee. This study is to summarize the surgical techniques and clinical outcome of domestic posterior-stabilized total knee arthroplasty. METHODS: Fifty-one patients including 19 males and 32 females underwent TKA by using TC-Dynamic from Jan. 2003 to Dec. 2004 were reviewed. The average age at the time of operation was (76.4 +/- 4.1) years (range, 71 to 84 years). Thirty-seven patients suffered from osteoarthritis and 14 patients were rheumatism arthritis. The courses of the disease ranged from 5 to 40 years and the symptoms were pain and limitation of motion. The knee rating score system (HSS) as well as X-rays of the lower extremity was used to evaluate the clinical results. RESULTS: All patients were followed up at the 3rd month after TKA and the duration of follow-up of 32 patients ranged from 48 to 61 months. The HSS scores before TKA was (53.3 +/- 6.7) (40 to 59) points. At the 3rd month and 48th month of follow-up, the HSS scores were (86.1 +/- 7.7) (63 to 95) and (83.5 +/- 8.1) (60 to 95) points respectively. The stress X-rays showed preoperative varus deformities from 9 degrees to 30 degrees with the average of (21.0 +/- 5.8) degrees and normal alignment of the lower extremities postoperative. There were no complications related to TC-Dynamic prosthesis and other complications such as infection, prosthetic loosening and dislocation of patella. CONCLUSION: There is a good mid-term clinical result of TC-Dynamic knee system, which is designed according to anatomical characteristic of Chinese knee joint. More attention should be paid to this knee system about the long term follow-up.

[Study on how much sterile saline should be used for efficient lavage during total knee arthroplasty].

OBJECTIVE: To investigate the volume of pulse lavage sufficient for removal of intraoperative bone and polymethyl methacrylate (PMMA) particles. METHODS: From 2007.11 to 2008.11, 18 patients with osteoarthritis underwent cemented TKA. Among the patients, 6 patients were male and 12 patients were female, ranging in age from 54 to 77 years, with an average of 61.5 years. The course of disease ranged from 3 to 9 years, mean 6.7 years. Pulse lavage with 1 L of sterile saline was performed for 8 times using a pulsatile irrigator after prothesis fixed. During pulse lavage, aspirated fluid was collected in a 1 L aliquot, and the weight of bone and PMMA particles in each fluid were measured. RESULTS: The weight of particles peaked in the first 1 L lavage fluid and gradually decreased until the 8th lavage fluid. Significant differences were found between the first vs second, second vs third, and third vs fourth lavage. However, no significant differences were found beyond the fourth lavage. CONCLUSION: The results of this study indicates that 4 L of pulse lavage is effective for removing the bone and PMMA particles during cemented TKA.

[Leg length discrepancy after total hip arthroplasty: impacts on postoperative function and patients' satisfaction].

OBJECTIVE: To explore the association between the leg length discrepancy and postoperative function after total hip arthroplasty. METHODS: From June 2004 to June 2007, the Leg length in 80 consecutive patients (38 males and 42 females, ranging in age from 56 to 86 years, with an average of 72.3 years) who underwent primary unilateral total hip arthroplasty was measured radiologically. Postoperative hip function and patients' satisfaction was assessed using the Oxford Hip Score (OHS) at three months and one year after surgery. RESULTS: (1) Leg length: 52 operated legs were longer than the other side by a mean of (9.2+/-3.2) mm (1 to 22 mm), in which 29 legs were longer for 1 to 10 mm (mean value 4.9 mm) and 23 legs were longer for 11 to 22 mm (mean value 14.6 mm); 13 operated legs were shorter by a mean of (6.4+/-2.1) mm (3 to 19 mm); 15 operated legs were of the same length as the other side. (2) Oxford hip scores: At three months after operation, the mean Oxford hip scores in patients with lengthened legs (two groups) were significantly higher (i.e., worse) than in the patients with shortened legs or in patients with legs of the same length. Significant difference in Oxford Hip Score was not found between the two groups of lengthened legs (1 to 10 mm vs 11 to 22 mm). Significant difference in Oxford Hip Score was also not found between the patients with shortened leg and the patients with legs of the same length. At one year after operation, the Oxford hip scores were significantly higher (i.e. worse) in the patients with lengthened limbs (11 to 22 mm) than in those of shortened limbs, or with limbs of equal length, or patients with lengthened legs (1 to 10 mm). No significantly differences of the Oxford hip scores were found within the patients with shortened limbs, the patients with limbs of equal length and the patients of lengthened limbs (1 to 10 mm). There was no significant difference between the Oxford hip scores at three months' follow-up and that at one year's follow-up in the lengthened group (11 to 22 mm), shortened group or same length group. The Oxford hip score was improved significantly one year after surgery when compared with that of three months after surgery in the lengthened group (1 to 10 mm). CONCLUSION: Leg length discrepancy, especially for that 11 to 20 mm longer than the healthy side, affects the functional outcome after total hip arthroplasty, and it does not relieve over time. Well planned measures should be taken to minimize leg length discrepancy.

[Rotational alignment in total knee arthroplasty].

Patellofemoral complications are the most common complications after total knee arthroplasty. The rotational alignment of the femoral component during operations is related to the occurrence of the patellofemoral complications, and is extremely important for the clinical outcomes of total knee arthroplasty.

[Observation of the efficacy of local multimodal analgesic drugs injection in total hip arthroplasty].

OBJECTIVE: To study the efficacy of periarticular multimodal analgesic drugs injection in total hip arthroplasty. METHODS: Seventy-six patients undergoing total hip arthroplasty were randomly divided into two groups, 38 patients received periarticular intraoperative injection of multimodal analgesic drugs, and others not do. Pain of patients were evaluated with a visual analog scale postoperatively, and all patients received patient-controlled analgesia for 24 hours after surgery. The consumption of patient-controlled analgesia was recorded at different time-points. RESULTS: Compared to the control group, visual analog scores for pain of the patients of injected group had significantly lower in the post-anesthetic-care unit and four hours after surgery. Patients of the injected group used significantly less patient-controlled analgesia at 6, 12 hours, and over the first 24 hours after surgery than the control group. No adverse effects resulted from the multimodal analgesic drugs were noted in the injected group. CONCLUSION: Periarticular injection of multimodal analgesic drugs in total hip arthroplasty can significantly reduce the postoperative pain of patients and the consumption of patient-controlled analgesia.