OBJECTIVE: To investigate the surgical technique and the short-term effectivenss of lateral unicompartmental knee arthroplasty (LUKA) through lateral approach in the treatment of valgus knee and to calculate the maximum value of the theoretical correction of knee valgus deformity. METHODS: A retrospective analysis was performed on 16 patients (20 knees) who underwent LUKA and met the selection criteria between April 2021 and July 2022. There were 2 males and 14 females, aged 57-85 years (mean, 71.5 years). The disease duration ranged from 1 to 18 years, with an average of 11.9 years. Knee valgus was staged according to Ranawat classification, there were 6 knees of type Ⅰ, 13 knees of type Ⅱ, and 1 knee of type Ⅲ. All patients were assigned the expected correction value of genu valgus deformity by preoperative planning, including the correction value of lateral approach, intra-articular correction value, and residual knee valgus deformity value. The actual postoperative corrected values of the above indicators were recorded and the theoretical maximum correctable knee valgus deformity values were extrapolated. The operation time, intraoperative blood loss, incision length, hospital stay, hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibia angle (mMPTA), joint line convergence angle (JLCA), posterior tibial slope (PTS), range of motion (ROM), Hospital for Special Surgery (HSS) score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score were also recorded for effectiveness evaluation. RESULTS: The patients' incision length averaged 13.83 cm, operation time averaged 85.8 minutes, intraoperative blood loss averaged 74.9 mL, and hospital stay averaged 6.7 days. None of the patients suffered any significant intraoperative neurological or vascular injuries. All patients were followed up 10-27 months, with a mean of 17.9 months. One patient with bilateral knee valgus deformities had intra-articular infection in the left knee at 1 month after operation and the remaining patients had no complication such as prosthesis loosening, dislocation, and infection. The ROM, HSS score, and WOMAC score of knee joint significantly improved at each time point after operation when compared to those before operation, and the indicators further improved with time after operation, the differences were all significant ( P<0.05). Imaging measurement showed that HKA, mLDFA, JLCA, and PTS significantly improved at 3 days after operation ( P<0.05) except for mMPTA ( P>0.05). Postoperative evaluation of the knee valgus deformity correction values showed that the actual intra-articular correction values ranged from 0.54° to 10.97°, with a mean of 3.84°. The postoperative residual knee valgus deformity values ranged from 0.42° to 5.30°, with a mean of 3.59°. The actual correction values of lateral approach ranged from 0.21° to 12.73°, with a mean of 4.26°. CONCLUSION LUKA through lateral approach for knee valgus deformity can achieve good early effectiveness. Preoperative planning can help surgeons rationally allocate the correction value of knee valgus deformity, provide corresponding treatment strategies, and the maximum theoretical correction value of knee valgus deformity can reach 25°.
Male ; Female ; Humans ; Arthroplasty, Replacement, Knee/methods* ; Retrospective Studies ; Blood Loss, Surgical ; Osteoarthritis, Knee/surgery* ; Knee Joint/surgery*

OBJECTIVE: To investigate the accuracy, safety, and short-term effectiveness of a domestic robot-assisted system in total knee arthroplasty (TKA) by a multicenter randomized controlled trial. METHODS: Between December 2021 and February 2023, 138 patients with knee osteoarthritis who received TKA in 5 clinical centers were prospectively collected, and 134 patients met the inclusion criteria were randomly assigned to either a trial group ( n=68) or a control group ( n=66). Seven patients had lost follow-up and missing data, so they were excluded and the remaining 127 patients were included for analysis, including 66 patients in the trial group and 61 patients in the control group. There was no significant difference ( P>0.05) in gender, age, body mass index, side, duration of osteoarthritis, Kellgren-Lawrence grading, preoperative Knee Society Score (KSS) and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score between the two groups. The trial group completed the TKA by domestic robot-assisted osteotomy according to the preoperative CT-based surgical planning. The control group was performed by traditional osteotomy plate combined with soft tissue release. Total operation time, osteotomy time of femoral/tibial side, intraoperative blood loss, and postoperative complications were recorded and compared between the two groups. The radiographs were taken at 5 and 90 days after operation, and hip-knee-ankle angle (HKA), lateral distal angle of femur (LDFA), and posterior tibial slope (PTS) were measured. The difference between the measured values of the above indexes at two time points after operation and the preoperative planning target values was calculated, and the absolute value (absolute error) was taken for comparison between the two groups. The postoperative recovery of lower limb alignment was judged and the accuracy was calculated. KSS score and WOMAC score were used to evaluate the knee joint function of patients before operation and at 90 days after operation. The improvement rates of KSS score and WOMAC score were calculated. The function, stability, and convenience of the robot-assisted system were evaluated by the surgeons. RESULTS: The total operation time and femoral osteotomy time of the trial group were significantly longer than those of the control group ( P<0.05). There was no significant difference in the tibial osteotomy time and the amount of intraoperative blood loss between the two groups ( P>0.05). The incisions of both groups healed by first intention after operation, and there was no infection around the prosthesis. Nine patients in the trial group and 8 in the control group developed lower extremity vascular thrombosis, all of which were calf intermuscular venous thrombosis, and there was no significant difference in the incidence of complications ( P>0.05). All patients were followed up 90 days. There was no significant difference in KSS score and WOMAC score between the two groups at 90 days after operation ( P>0.05). There was significant difference in the improvement rate of KSS score between the two groups ( P<0.05), while there was no significant difference in the improvement rate of WOMAC score between the two groups ( P>0.05). Radiological results showed that the absolute errors of HKA and LDFA in the trial group were significantly smaller than those in the control group at 5 and 90 days after operation ( P<0.05), and the recovery accuracy of lower limb alignment was significantly higher than that in control group ( P<0.05). The absolute error of PTS in the trial group was significantly smaller than that in the control group at 5 days after operation ( P<0.05), but there was no significant difference at 90 days between the two groups ( P>0.05). The functional satisfaction rate of the robot-assisted system was 98.5% (65/66), and the satisfaction rates of stability and convenience were 100% (66/66). CONCLUSION Domestic robot-assisted TKA is a safe and effective surgical treatment for knee osteoarthritis, which can achieve favorable lower limb alignment reconstruction, precise implant of prosthesis, and satisfactory functional recovery.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Osteoarthritis, Knee/surgery* ; Blood Loss, Surgical ; Robotics ; Knee Joint/surgery* ; Knee Prosthesis ; Retrospective Studies

The correct alignment of the knee joint is considered to be one of the most influential factors in determining the long-term prognosis after total knee arthroplasty(TKA). In order to achieve the correct alignment goal, many different alignment concepts and surgical techniques have been established. For example, mechanical alignment(MA), kinematic alignment(KA) and functional alignment(FA) have their own characteristics. MA focuses on achieving neutral alignment of the limbs, parallel and equal bone gaps during stretching and flexion. KA aims to restore the patient 's natural joint line, make the joint level and angle normal and improve the physiological soft tissue balance, and strive to reproduce the normal knee function;among them, functional alignment(FA) developed with robot-assisted surgery technology is a relatively new alignment concept. It not only considers the alignment of the body, but also aims to achieve flexion and extension balance, while respecting the native soft tissue capsule. It not only restores the plane and slope of the in situ joint line accurately during the operation, but also takes into account the balance of soft tissue, which is a better alignment method. Therefore, it is of great significance to correctly construct the lower limb force line of patients, which is helpful to restore knee joint function, relieve pain symptoms and prolong the service life of prosthesi. However, compared with traditional TKA, the operation time of robot-assisted FA-TKA is prolonged, which means that the probability of postoperative infection will be greater. At present, most studies of FA technology report short-term results, and the long-term efficacy of patients is not clear. Therefore, long-term research results are needed to support the application of this technology. Therefore, the author makes a review on the research status of functional alignment.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Robotics ; Knee Joint/surgery* ; Osteoarthritis, Knee/surgery* ; Knee ; Knee Prosthesis ; Biomechanical Phenomena

BACKGROUND: Synovectomy has been introduced into total knee arthroplasty (TKA) with the aim of relieving pain and inflammation of the synovium. However, there are no long-term, comparative data to evaluate the effect of synovectomy in TKA. This study was aimed at assessing pain, function, and complications in patients undergoing synovectomy during TKA for osteoarthritis (OA) at long-term follow-up. METHODS: This was a prospective randomized controlled trial of 42 consecutive patients who underwent staged bilateral TKA. Patients undergoing the first-side TKA were allocated to receive TKA with or without synovectomy followed by a 3-month washout period and crossover to the other strategy for the opposite-side TKA. The overall efficacy of both strategies was evaluated by determination of blood loss, the Knee Society score (KSS), and knee inflammation conditions during a 3-month postoperative period. The postoperative pain, range of motion (ROM), and complications were sequentially evaluated to compare the two groups until 10 years after surgery. RESULTS: At the 10-year follow-up, both groups had a similarly significantly improved ROM (114.88 ± 9.84° vs. 114.02 ± 9.43°, t  = 0.221, P  = 0.815) and pain relief with no differences between the two groups (1.0 [1.0] vs. 1.0 [1.5], U  = 789.500, P  = 0.613). Similar changes in total blood loss, KSS, and knee inflammation were found in both groups during 3 months postoperatively ( P  > 0.05). Additionally, there was no significant difference regarding complications and satisfaction between the two groups ( P  > 0.05). CONCLUSIONS: Synovectomy in conjunction with TKA for primary OA does not seem to provide any benefit regarding postoperative pain, ROM, and satisfaction during a 10-year follow-up. In addition, it may not result in more blood loss and increased incidence of long-term complications. Based on our long-term findings, it should not be performed routinely. TRIAL REGISTRATION Chinese Clinical Trial Registry, ChiCTR-INR-16008245; https://www.chictr.org.cn/showproj.aspx?proj=13334 .
Humans ; Arthroplasty, Replacement, Knee/methods* ; Synovectomy/methods* ; Osteoarthritis, Knee/surgery* ; Prospective Studies ; Pain, Postoperative ; Inflammation/etiology* ; Range of Motion, Articular ; Knee Joint/surgery* ; Treatment Outcome ; Knee Prosthesis/adverse effects*

OBJECTIVE: To investigate the early efficacy of Mako robot-assisted total knee arthroplasty (TKA) in the treatment of knee osteoarthritis (KOA) and summarize the initial application experience. METHODS: Retrospective analysis of 73 patients with KOA treated with Mako robot-assisted TKA from June 2021 to December 2021. There were 16 males and 57 females, aged from 54 to 81 years old with an average of (67.8±6.6) years old. The hip knee and ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), lateral femoral component angle (LFCA) and lateral tibial component angle (LTCA) were recorded and analyzed. WOMAC score and KSS were used to compare the functional recovery of patients preoperatively, 3 and 6 months postoperatively. RESULTS: All the 73 patients were successfully treated without serious complications such as vascular and nerve injury, and all the incisions healed well at stageⅠwithout infection. The patients were followed up from 4 to 11 months with an average of (7.0±2.7) months, and the satisfaction rate of the last follow-up was 90.41% (66/73). WOMAC scores were (23.1±5.4) at 3 months and (14.8±4.1) at 6 months postoperatively. KSS clinical scores were ( 76.1±4.0) at 3 months and (82.1±3.7) at 6 months postoperatively;KSS functional scores were (74.3±3.1) at 3 months and (78.6±2.1) at 6 months after operation. Postoperative imaging showed good position of the prosthesis, HKA angle was (178.5±2.1)°, LDFA was (91.2±1.8)°, MPTA was(89.9±1.5) °, LFCA was (7.6±3.1)°, LTCA was (88.2±1.1)°. The mechanical axis within ±3° in sixty cases(82.2%), and the mechanical axis within ±6° in all the patients. CONCLUSION Mako robot-assisted TKA is a safe and effective surgery in the treatment of knee osteoarthritis, which exhibited good efficacy in the correction of lower limb alignment, soft tissue balance and improvement of knee function. The long-term efficacy needs further follow-up observation.
Male ; Female ; Humans ; Middle Aged ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/methods* ; Osteoarthritis, Knee/surgery* ; Retrospective Studies ; Robotics ; Knee Joint/surgery*

OBJECTIVE: To investigate the clinical efficacy of unicompartmental knee arthroplasty (UKA) in the treatment of knee osteoarthritis in patients over 75 years old. METHODS: The clinical efficacy of primary fixed platform UKA in patients with osteoarthritis, was retrospectively analyzed from October 2014 to November 2020. Age, body mass index (BMI), range of motion (ROM), preoperative joint function score, the quality of life score and other preoperative indicators were measured by propensity score matching (PSM). The patients were divided into elderly group (≥75 years old) and control group (<75 years old). Oxford knee score(OKS), Western Ontario McMaster Universities osteoarthritis index(WOMAC), Short Form-12 including physical component summary (PCS), mental component summary(MCS), minimal clinically important difference(MCID ) and clinical complications were evaluated preoperatively and postoperatively. RESULTS: A total of 514 patients were analyzed, 428 patients fulfilled the inclusion criteria. A propensity-score matching study was conducted to eliminate confounding factors. After 1∶2 propensity match, there were 84 patients in elderly group (≥75 years), age ranged from 75 to 88 years old, with an average of (78.79±3.08) years old, and 168 patients in control group (<75 years), age ranged from 47 to 74 years old, with an average of (64.10±5.96)years old. The follow-up duration of two groups ranged from 12 to 84 months with an average of (29.35±16.52) months in elderly group, and 12 to 85 months with an average of (31.83±17.34) months in control group. There was only significant difference in age between the elderly and control groups preoperatively (P<0.01). Postoperatively, the elderly group showed significantly higher WOMAC (P<0.01) and lower SF-12 PCS scores (P<0.01) as compared to the control group. There was no significant difference between the elderly group and the control group in knee range of motion, OKS and the proportion of each scoring system reaching the minimum clinical difference value (P>0.05). In the aspect of preperative complications, the elderly group exhibited more surgical site complications and postoperative delirium compared to control group(P<0.05). The differences in other indicators including deep vein thrombosis, acute urinary retention, cardiovascular events, cerebrovascular events and radiolucent lines around prothesis were not statistically significant(P>0.05). CONCLUSION UKA in the treatment of elderly patients over 75 years old with knee osteoarthritis was safe and feasible, and could obtain satisfactory short-term efficacy.
Humans ; Aged ; Aged, 80 and over ; Middle Aged ; Osteoarthritis, Knee/surgery* ; Knee Prosthesis ; Retrospective Studies ; Propensity Score ; Quality of Life ; Knee Joint/surgery* ; Arthroplasty, Replacement, Knee/methods* ; Treatment Outcome

OBJECTIVE: To compare the short-term effectiveness of "SkyWalker" robot-assisted total knee arthroplasty (TKA) and traditional TKA. METHODS: A clinical data of 54 patients (54 knees) with TKA who met the selection criteria between January 2022 and March 2022 was retrospectively analyzed. Among them, 27 cases underwent traditional TKA (traditional operation group) and 27 cases underwent "SkyWalker" robot-assisted TKA (robot-assisted operation group). There was no significant difference between the two groups ( P>0.05) in terms of gender, age, body mass index, osteoarthritis side, disease duration, and preoperative Knee Society Score (KSS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), visual analogue scale (VAS) score, hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), and posterior proximal tibial angle (PPTA). The operative time, intraoperative bleeding volume, surgery-related complications, the KSS, WOMAC, and VAS scores before operation and at 6 months after operation, and Forgotten Joint Score (FJS) at 6 months after operation were recorded. X-ray films were taken to review the prosthesis position and measure HKA, LDFA, MPTA, and PPTA. The differences of the clinical and imaging indicators between before and after operation were calculated and statistically analyzed. RESULTS: The operations were completed successfully in both groups. There was no significant difference in the operative time and intraoperative bleeding volume between the two groups ( P>0.05). After operation, 1 case of incision nonunion and 1 case of heart failure occurred in the traditional operation group, while no surgery-related complications occurred in the robotic-assisted operation group. The incidences of surgical complications were 7.4% (2/27) in the traditional operation group and 0 (0/27) in the robotic-assisted operation group, with no significant difference ( P=0.491). Patients in both groups were followed up 6 months. KSS score, WOMAC score, VAS score, and ROM significantly improved in both groups at 6 months after operation when compared with preoperative ones ( P<0.05). There was no significant difference between the two groups ( P>0.05) in the differences between the pre- and post-operative values of the clinical indicators and FJS scores at 6 months after operation. X-ray films showed that the lower extremity force lines of the patients improved and the knee prostheses were in good position. Except for LDFA in the robot-assisted operation group, HKA, LDFA, MPTA, and PPTA significantly improved in both groups at 6 months after operation when compared with the preoperative ones ( P<0.05). There was no significant difference between the two groups in the differences between the pre- and post-operative values of the radiological indicators ( P>0.05). CONCLUSION The "SkyWalker" robot-assisted TKA is one of the effective methods for the treatment of knee osteoarthritis and had good short-term effectiveness. But the long-term effectiveness needs to be further studied.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Knee Joint/surgery* ; Knee Prosthesis ; Osteoarthritis, Knee/surgery* ; Retrospective Studies ; Robotics ; Treatment Outcome

OBJECTIVE: To review the research progress of injection sites of local infiltration analgesia (LIA) in total knee arthroplasty (TKA). METHODS: The relevant domestic and foreign literature in recent years was extensively reviewed. The neuroanatomy of the knee, and the research progress of the selection and the difference of effectiveness between different injection sites of LIA in clinical studies were summarized. RESULTS: Large concentrations of nociceptors are present throughout the various tissues of the knee joint. Patellar tendon, subpatellar fat pad, lateral collateral ligament insertions, iliotibial band insertions, suprapatellar capsule, and posterior capsule were more sensitive to pain. Most current studies support injections into the lateral capsule, collateral ligament, retinaculum, quadriceps tendon, fat pad, and subcutaneous tissue. Whether to inject into the back of the knee and subperiosteum is controversial. CONCLUSION The relative difference of knee tissue sensitivity to pain has guiding significance for the selection of LIA injection site after TKA. Although researchers have conducted clinical trials on injection site and technique of LIA in TKA, there are certain limitations. The optimal scheme has not been determined yet, and further studies are needed.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Pain, Postoperative/prevention & control* ; Pain Management/methods* ; Analgesia/methods* ; Knee Joint/anatomy & histology* ; Anesthesia, Local/methods*

Periprosthetic gout flare is a rare arthritic condition after total knee arthroplasty, but the symptoms of gout may have often been mistaken as acute periprosthetic infection given their similarity. Misdiagnosis as periprosthetic infection can lead to unnecessary surgery, long-term dependence on anti-biotics, and even malfunction of the involved knee joint. Here, we report a case study of a patient with immunodeficiency condition of long-term oral glucocorticoid and diabetes mellitus, who had undergone a knee replacement 8 weeks before. The initial symptoms of fever and joint pain together with the dysfunction of her right knee with elevated inflammatory markers, such as increased serum leukocytes, erythrocyte sedimentation rate, C-reactive protein, and synovial cell counts led to a diagnosis of acute periprosthetic infection. Arthrocentesis and bacterial culture were performed preoperatively. According to the current Musculoskeletal Infection Society (MSIS) criteria for diagnosis of periprosthetic infection, the case was classified as periprosthetic infection and a prosthesis retained debridement surgery was performed. However we got negative culture results in all the pre-operative and intro-operative samples. The symptoms as well as the laboratory inflammatory markers improved shortly after the debridement surgery until the 11th day when all the similar systemic and local symptoms recurred. With a remedial crystal analysis of synovial fluid from the patient, gouty flare was found to be the cause of acute arthritis finally. Accor-dingly, after anti-gout medications were administrated, the symptoms associated with acute arthritis gra- dually subsided, and there was no recurrence during a 24-month follow-up. This article described the cli-nical manifestation, diagnosis and differential diagnosis, treatment of a case of periprosthetic gout. Although relatively rare, gout should be considered as a differential diagnosis in suspected periprosthetic infection. Current criteria for periprosthetic infection can not exclude the diagnosis of periprosthetic gout flare, it is therefore imperative that the analysis of joint aspirate for crystals be conducted to determine the correct course of treatment, or unnecessary surgical procedure may be performed in periprosthetic gout case.
Humans ; Female ; Arthroplasty, Replacement, Knee/methods* ; Gout/complications* ; Prosthesis-Related Infections/surgery* ; Symptom Flare Up ; C-Reactive Protein/analysis* ; Biomarkers/analysis*

BACKGROUND: Total knee arthroplasty (TKA) can reduce severe joint pain and improve functional disability in hemophilia. However, the long-term outcomes have rarely been reported in China. Therefore, this study aimed to evaluate the long-term outcomes and complications of TKA in Chinese patients with hemophilic arthropathy. METHODS: We retrospectively reviewed patients with hemophilia who underwent TKA between 2003 and 2020, with at least 10 years of follow-up. The clinical results, patellar scores, patients' overall satisfaction ratings, and radiological findings were evaluated. Revision surgery for implants during the follow-up period was recorded. RESULTS: Twenty-six patients with 36 TKAs were successfully followed up for an average of 12.4 years. Their Hospital for Special Surgery Knee Score improved from an average of 45.8 to 85.9. The average flexion contracture statistically significantly decreased from 18.1° to 4.2°. The range of motion (ROM) improved from 60.6° to 84.8°. All the patients accepted patelloplasty, and the patients' patellar score improved from 7.8 preoperatively to 24.9 at the last follow-up. There was no statistically significant difference in clinical outcomes between the unilateral and bilateral procedures, except for a better ROM at follow-up in the unilateral group. Mild and enduring anterior knee pain was reported in seven knees (19%). The annual bleeding event was 2.7 times/year at the last follow-up. A total of 25 patients with 35 TKAs were satisfied with the procedure (97%). Revision surgery was performed in seven knees, with 10- and 15-year prosthesis survival rates of 85.8% and 75.7%, respectively. CONCLUSIONS TKA is an effective procedure for patients with end-stage hemophilic arthropathy, which relieves pain, improves knee functions, decreases flexion contracture, and provides a high rate of satisfaction after more than ten years of follow-up.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Hemophilia A/surgery* ; Follow-Up Studies ; Retrospective Studies ; Treatment Outcome ; Knee Joint/surgery* ; Range of Motion, Articular ; Arthritis/complications* ; Pain ; Contracture/surgery* ; Surgeons ; Knee Prosthesis