Objective To measure the included angle between tibia anatomical axis and anterior cortex, and to define the relative position of them in order to give direction in placement of tibia extra-medullary alignment bar during total knee arthroplasty. Methods A total of 100 healthy volunteers were included (49 left knees and 51 right knees). There were 52 males and 48 females, aged 20-86 years with an average age of 45.2 years (20-35 years in 29 cases, 35-50 years in 32 cases, and over 50 years in 39 cases). The tibiofibular lateral X-ray films were taken to measure the included angle between tibia anatomical axis and anterior cortex with AutoCAD2004 system. The samples were grouped according to gender, age, and side. Results The included angles between tibia anatomical axis and anterior cortex ranged from 3.007 to 3.021° with an average of 3.001°; the angles were (2.965 ± 0.361)° in male and (3.041 ± 0.311)° in female; the angles were (2.996 ± 0.332)° in the left knee and (3.006 ± 0.347)° in the right knee; and the angles were (2.918 ± 0.346)° in 20-35 years age group, (3.060 ± 0.330)° in 35-50 years age group, and (3.014 ± 0.336)° in over 50 years age group. No significant difference was found in the included angle between tibia anatomical axis and anterior cortex between male and female, among different ages, and between left and right knees (P gt; 0.05). Conclusion The included angle between tibia anatomical axis and anterior cortex is about 3°, so tibia extra-medullary alignment bar should be placed at the angle of 3° with anterior cortex during total knee arthroplasty.
ObjectiveTo explore the imaging features of intramedullary guide rod and its influence on the alignment of the femoral prosthesis in unicompartmental knee arthroplasty (UKA). MethodsBetween August 2016 and November 2016, 50 patients (50 knees) with primary anteromedial osteoarthritis were treated with UKA by Oxford MicroPlasty minimally invasive replacement system. There were 10 males and 40 females. The age ranged from 62 to 77 years with an average of 68.8 years. Preoperative varus and flexion deformity angles were (5.22±3.46)° and (7.42±2.65)°, respectively. The knee range of motion (ROM) was (106.85±7.62)°. The Hospital for Special Surgery (HSS) score was 68.26±4.65. The angles between the femoral intramedullary guide rod and the anatomical axis of femur on the coronal and sagittal planes, the femoral component valgus/varus angle (FCVA), the femoral component posterior slope angle (FCPSA), knee varus deformity angle, and knee flexion deformity angle were measured by intra- and post-operative X-ray films. The postoperative ROM and HSS score were measured. ResultsIntraoperative X-ray films measurement showed that the lateral side angles between femoral intramedullary guide rod and femoral anatomical axis were observed on coronal plane, and the angles ranged from 0.28 to 2.06° with an average of 0.96°. While the posterior side angles were observed on sagittal plane, and the angles ranged from 0.09 to 0.48° with an average of 0.23°. The angulations (>1°) between femoral intramedullary part guide rod and outside part of the rod were confirmed in 12 cases (24%) on coronal plane. Postoperative femoral prosthesis were mild varus in 38 patients (76%). The FCVA ranged from –1.76 to 4.08° with an average of 2.21°. The FCPSA ranged from 7.12 to 13.86° with an average of 9.16°. All patients were followed up 22-26 months, with an average of 24.5 months. The incisions healed by first intention. At last follow-up, the varus and flexion deformity angles were (1.82±1.05) and (2.54 ± 1.86)°, respectively. ROM was (124.62±5.85)° and HSS score was 91.58±3.65. There were significant differences between pre- and post-operative parameters (P<0.05). No complication such as dislocation or aseptic loosening of the prosthesis occurred during the follow-up. ConclusionUKA by Oxford MicroPlasty minimally invasive replacement system can obtain accurate femoral prosthesis position with the help of intramedullary guide system, and the effectiveness is excellent.
Objective To observe the posterior condylar offset (PCO) changes and anteroposterior femorotibial translation, to investigate the influence of them on the maximum knee range of flexion (ROF) in patients with posterior cruciatesacrificingself al ignment bearing total knee arthroplasty (TKA). Methods The cl inical data were analyzed retrospectively from 40 patients (40 knees) undergoing primary unilateral TC-PLUSTM SB posterior cruciate-sacrificing self al ignment andbearing TKA for osteoarthritis between January 2007 and June 2009. There were 18 males and 22 females with an average age of 70.6 years (range, 56-87 years). The disease duration was 5-14 years (mean, 9.1 years). The locations were the left side in 11 cases and the right side in 29 cases. Preoperative knee society score (KSS) and ROF were 48.0 ± 5.5 and (77.9 ± 9.0)°, respectively. The X-ray films were taken to measure PCO and anteroposterior femorotibial translation. Multi ple regression analysis was performed based on both the anteroposterior femorotibial translation and PCO changes as the independent variable, and maximum knee flexion as the dependent variable. Results All incisions healed by first intention. The patients were followed up 12-19 months (mean, 14.7 months). At last follow-up, there were significant differences in the KSS (91.9 ± 3.7, t=— 77.600, P=0.000), the ROF [(102.0 ± 9.3)°, t=— 23.105, P=0.000] when compared with preoperative values. Significant difference was observed in PCO (t=3.565, P=0.001) between before operation [(31.6 ± 5.5) mm] and at last follow-up [(30.6 ± 5.9) mm]. At ast follow-up, the anteroposterior femorotibial translation was (— 1.2 ± 2.1) mm (95%CI: — 1.9 mm to — 0.6 mm); femoral roll forward occurred in 27 cases (67.5%), no roll in 1 case (2.5%), and femoral roll back in 12 cases (30.0%). By multiple regression analysis (Stepwise method), the regression equation was establ ished (R=0.785, R2=0.617, F=61.128, P=0.000). Anteroposterior femorotibial translation could be introducted into the equation (t=7.818, P=0.000), but PCO changes were removed from the equation (t=1.471, P=0.150). Regression equation was y=25.587+2.349x. Conclusion Kinematics after TC-PLUSTM SB posterior cruciate-sacrificing self al ignment bearing TKA with posterior cruciate l igament-sacrificing show mostly roll forwardof the femur relative to the tibia, which have a negative effect on postoperative range of motion. There is no correlation between PCO changes and postoperative change in ROF in TC-PLUSTM SB posterior cruciate-sacrificing self al ignment bearing TKA.
Objective To review the progress of total ankle arthroplasty (TAA) in treatment of end-stage ankle osteoarthritis (AOA). Methods The domestic and foreign literatures about TAA in recent years were reviewed. The current status and progress of TAA were summarized from the results of traditional and computer-assisted TAA clinical outcomes. Results End-stage AOA often leads to severe pain and dysfunction, and arthrodesis is still the main selective treatment option. In recent years, with the advancement of surgical techniques and prosthesis design, TAA which can remain joint mobility has increased gradually, and the surgical results also have significant progress. Accurate prosthesis implant and mechanical alignment restoration are critical factors for TAA, and surgery-related malalignment is correlative to the prosthesis failure. Computer assisted patient-specific guide can simplify the TAA procedures and obtain the accuracy of tibia and talus osteotomy. Conclusion The clinical efficiency of preoperative CT based patient-specific guide technology for TAA needs further clinical follow-up. Meanwhile, it is necessary to further develop intraoperative navigation and robotic surgery system suitable for TAA.
Objective To review the advance in the researchand clinical application of the tibial rotational alignment technique in the total knee arthroplasty in China and abroad. Methods The recent literature concerned with the tibial rotational alignment technique in the totalknee arthroplasty was extensively reviewed and briefly summarized. Results According to the literature reviewed, the traditional tibial rotational references for the total knee arthroplasty were affected by many factors, so that the references were not accurate enough. There have been no unified references.ConclusionChoosing the range from the medial border of the tibial tubercle to the medial 1/3 of the tibial tubercle, decided by the degrees of the varus deformities and the valgus deformities, to determine the rotaional alignment of the tibial component will create an optimal tibiofemoral rotational alignment.
ObjectiveTo investigate the effect of preoperative valgus or varus deformity on the prosthesis installation and alignment restoration in total knee arthroplasty (TKA). MethodsBetween January 2012 and December 2013, 198 patients (245 knees) with osteoarthritis underwent primary TKA, and the clinical data were retrospectively analyzed. There were 23 males and 175 females, with the average age of 67 years (range, 43-90 years). Single knee and double knees were involved in 151 and 47 cases respectively. The disease duration was from 1 month to 30 years (mean, 8.99 years). The anteroposterior X-ray films of whole lower limbs were taken, and the femorotibial angle (FT) was measured before operation and at 1 week after operation; the mechanical femoral angle (MF) and the anatomical tibial angle (AT) at 1 week after operation were measured. The correlation analysis was made for pre-and post-operative FT, MF, and AT. According to the valgus or varus deformity before operation, all patients were divided into 5 groups:≥20° varus (group A), 10-20° varus (group B), ≤10° varus (group C), < 10° valgus (group D), and≥10° valgus (group E), and the above indicators were compared between groups. And the rate of the good limb alignment was recorded after operation. ResultsThe pre-and post-operative FT were (171.53±9.12) and (177.38±3.57)° respectively, and postoperative MF and AT were (89.00±2.68) and (88.62±2.16)° respectively. Preoperative FT was associated with postoperative FT and MF (r=0.375, P=0.000; r=0.386, P=0.000), but it was not correlated with AT (r=0.024, P=0.710). Postoperative FT was associated with MF and AT (r=0.707, P=0.000; r=0.582, P=0.000). Postoperative FT was significantly increased when compared with preoperative FT in each group (P < 0.05). There were significant differences in preoperative FT between groups (P < 0.05). There were significant differences in postoperative FT when compared group A with groups B, C, D, and E (P < 0.05), and when compared groups B and C with groups D and E (P < 0.05), but there was no significant difference between groups B and C, and between groups D and E (P>0.05). The rate of good alignment was 70.2% (172/245); it was 27.8% (5/18), 66.0% (62/94), 74.4% (67/90), 88.9% (32/36), and 85.7% (6/7) in groups A, B, C, D, and E respectively, showing significant differences between groups (P < 0.05). There was no significant difference in postoperative AT between groups (P>0.05). Except for between group D and group E (P>0.05), significant difference in MF was shown between the other groups (P < 0.05). ConclusionThe more severe deformity of lower limb before TKA, the higher risk of deviation for prosthesis installation and poor alignment in TKA.
ObjectiveTo observe the character of spino-pelvic sagittal alignment in patients with high-grade L5 isthmic spondylolisthesis, and to analyze the sagittal alignment alteration after operation. MethodBetween January 2009 and June 2014, 25 patients with high-grade L5 isthmic spondylolisthesis underwent posterior surgery, and the clinical data were retrospectively analyzed as study group. There were 14 males and 11 females with a mean age of 42.5 years (range, 20-65 years). The mean disease duration was 6 months (range, 3-12 months). According to the Meyerding evaluating system, 15 cases were rated as degree III, and 10 cases as degree IV. Eighty healthy adult volunteers were recruited simultaneously as control group. The lumbar sacral angle (LSA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), and sagittal vertical axis (SVA) were measured on preoperative and last follow-up standing full length lateral X-ray films. And these parameters were compared between study group (preoperative parameters) and control group. Then the patients in study group were divided into 2 subgroups according to Hresko's method:the balanced pelvis subgroup (n=14) and unbalanced pelvis subgroup (n=11) . The sagittal parameters were compared between 2 subgroups, and the alteration of sagittal parameters before surgery and at last follow-up was analyzed in each subgroup respectively. ResultsAll patients in study group were followed up 18 months on average (range, 6-48 months). After surgery, spondylolisthesis was reduced from degree III to degree 0 in 12 cases and to degree I in 3 cases, and from degree IV to degree 0 in 6 cases and to degree I in 4 cases. Bone fusion was obtained in all patients at last follow-up. The preoperative PI, SS, PT, and SVA of study group were significantly greater than those of control group (P<0.05) , while the TK was significantly smaller than that of control group (P<0.05) . In the balanced pelvis subgroup, LSA, LL, and SVA at last follow-up significantly decreased while TK significantly increased when compared with preoperative ones (P<0.05) . In the unbalanced pelvis subgroup, LSA, PT, and SVA at last follow-up significantly decreased while SS, LL, and TK significantly increased when compared with preoperative ones (P<0.05) . The preoperative LSA and PT in the unbalanced pelvis subgroup were significantly greater, while SS, LL, and TK were significantly smaller than those of balanced pelvis subgroup (P<0.05) ; while at last follow-up, significant differentce was found only in LSA between 2 subgroups (P<0.05) . ConclusionsThe LSA should be paid more attention in surgery to assure recovery of the sagittal balance because patients with high-grade L5 isthmic spondylolisthesis have greater PI, abnormal lumbosacral kyphosis, and sagittal imbalance.
ObjectiveTo summarize the methods of tibial prosthesis rotation alignment in total knee arthroplasty, and provide reference for clinicians to select and further study the methods of tibial prosthesis rotation alignment.MethodsThe advantages and disadvantages of various tibial prosthesis rotation alignment methods were analyzed and summarized by referring to the relevant literature at home and abroad in recent years.ResultsThere are many methods for tibial prosthesis rotation alignment, including reference to relevant anatomical landmarks, range of motion (ROM) technique, computer-assisted navigation, and personalized osteotomy. The inner one-third of the tibial tuberosity is a more accurate reference anatomical landmark, but the obesity, severe knee deformity and dysplasia have impacts on the precise placement of the tibial prosthesis. ROM technique do not need to refer to the anatomical landmark of the tibia, and aren’t affected by landmark variation. It can be used for severe knee valgus deformity and the landmarks that are difficult to identify. However, it may cause internal rotation of tibial prosthesis. Computer- assisted navigation and personalized osteotomy can achieve more accurate alignment in sagittal, coronal, and rotational alignment of femoral prosthesis. However, due to the lack of reliable anatomical landmarkers related to tibia fixation, it is still controversial whether it can help the alignment of tibial prosthesis rotation.ConclusionThe surgeon should master the methods of rotation and alignment of tibial prosthesis, make preoperative plans, select appropriate alignment methods for different patients, and achieve individualization. Meanwhile, several anatomical landmarkers should be referred to properly during the operation, which can be used to detect the correct placement of tibial prosthesis and avoid large rotation error.
ObjectiveTo investigate the improvement of femoral rotation alignment in total knee arthroplasty (TKA) by robotic-arm assisted positioning and osteotomy and its short-term effectiveness.MethodsBetween June 2020 and November 2020, 60 patients (60 knees) with advanced osteoarthritis of the knee, who met the selection criteria, were selected as the study subjects. Patients were randomly divided into two groups according to the random number table method, with 30 patients in each group. Patients were treated with robotic-arm assisted TKA (RATKA) in trial group, and with conventional TKA in control group. There was no significant difference in gender, age, side and course of osteoarthritis, body mass index, and the preoperative hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), posterior condylar angle (PCA), knee society score-knee (KSS-K) and KSS-function (KSS-F) scores between the two groups (P>0.05). The clinical (KSS-K, KSS-F scores) and imaging (HKA, LDFA, MPTA, PCA) evaluation indexes of the knee joints were compared between the two groups at 3 months after operation.ResultsAll patients were successfully operated. The incisions in the two groups healed by first intention, with no complications related to the operation. Patients in the two groups were followed up 3-6 months, with an average of 3.9 months. KSS-K and KSS-F scores of the two groups at 3 months after operation were significantly higher than those before operation (P<0.05), but there was no significant difference between the two groups (P>0.05). X-ray re-examination showed that the prosthesis was in good position, and no prosthesis loosening or sinking occurred. HKA, MPTA, and PCA significantly improved in both groups at 3 months after operation (P<0.05) except LDFA. There was no significant difference in HKA, LDFA, and MPTA between the two groups (P>0.05). PCA in trial group was significantly smaller than that in control group (t=2.635, P=0.010).ConclusionRATKA can not only correct knee deformity, relieve pain, improve the quality of life, but also achieve the goal of restoring accurate femoral rotation alignment. There was no adverse event after short-term follow-up and the effectiveness was satisfactory.
Objective To evaluate the early effectiveness of navigation-free robot-assisted total knee arthroplasty (TKA) compared to traditional TKA in the treatment of knee osteoarthritis combined with extra-articular deformities. Methods The clinical data of 30 patients with knee osteoarthritis combined with extra-articular deformities who met the selection criteria between June 2019 and January 2024 were retrospectively analyzed. Fifteen patients underwent CORI navigation-free robot-assisted TKA and intra-articular osteotomy (robot group) and 15 patients underwent traditional TKA and intra-articular osteotomy (traditional group). There was no significant difference in age, gender, body mass index, affected knee side, extra-articular deformity angle, deformity position, deformity type, and preoperative knee range of motion, American Knee Society (KSS) knee score and KSS function score, and lower limb alignment deviation between the two groups (P>0.05). The operation time, intraoperative blood loss, and complications of the two groups were recorded and compared. The knee range of motion and lower limb alignment deviation were recorded before operation and at 6 months after operation, and the knee joint function was evaluated by KSS knee score and function score. Results There was no significant difference in operation time between the two groups (P>0.05); the intraoperative blood loss in the robot group was significantly less than that in the traditional group (P<0.05). Patients in both groups were followed up 6-12 months, with an average of 8.7 months. The incisions of all patients healed well, and there was no postoperative complication such as thrombosis or infection. At 6 months after operation, X-ray examination showed that the position of the prosthesis was good in both groups, and there was no loosening or dislocation of the prosthesis. The knee joint range of motion, the lower limb alignment deviation, and the KSS knee score and KSS function score significantly improved in both groups (P<0.05) compared to preoperative ones. The changes of lower limb alignment deviation and KSS function score between pre- and post-operation in the robot group were significantly better than those in the traditional group (P<0.05), while the changes of other indicators between pre- and post-operation in the two groups were not significant (P>0.05). Conclusion Compared to traditional TKA, navigation-free robot-assisted TKA for knee osteoarthritis with extra-articular deformities results in less intraoperative blood loss, more precise reconstruction of lower limb alignment, and better early effectiveness. However, long-term effectiveness require further investigation.