We report the case of a polyethylene tibial post fracture in a 72-year-old woman 14 months after a Scorpio posterior-stabilized (PS) total knee arthroplasty. The polyethylene wear was found around the fracture site of the post, especially over the anterior aspect of the post base. The failure mechanism of the post fracture in the present case was anterior impingement with excessive wear over the base of the anterior aspect of the tibial post, which became a stress-riser of post and cam articulation. This is the first report of a polyethylene tibial post fracture of a Scorpio PS prosthesis.
Aged ; *Arthroplasty, Replacement, Knee ; Female ; Humans ; Knee Joint/radiography ; Knee Prosthesis/*adverse effects ; Osteoarthritis, Knee/surgery ; *Polyethylenes ; *Prosthesis Failure ; Reoperation

OBJECTIVE: To investigate the effect of tibial coronal curvature on the alignment of tibial prosthesis in patients undergoing total knee arthroplasty (TKA). METHODS: From July 2019 to April 2021, 100 patients with knee osteoarthritis were treated with total knee arthroplasty. Before operation, the full-length films of lower limbs were taken and the tibial bowing angle(TBA) was measured. TBA more than 2° was tibial bending, which was divided into tibial bending group and non bending group. There were 40 cases in tibial bending group, 9 males and 31 females, aged 56 to 84 years old with an average of (69.22±7.10) years. There were 60 cases in the non bending group, 19 males and 41 females, aged from 51 to 87 years old with an average of (70.80±7.21) years. The preoperative tibial length (TL) and medial proximal tibial angle (MPTA) were measured and compared between the two groups. The full-length X-rays of the lower limbs were taken again 3 days to 1 week after operation. The medial angle of the tibial component coronal aligement angle (TCCA) and the outilier rate of force line of the tibial prosthesis were measured and compared between the two groups. Pearson method was used to analyze the correlation between TCCA and age, TCCA and height, TCCA and weight, TCCA and BMI, TCCA and TBA, TCCA and TL, TCCA and MPTA; Spearman method was used to analyze the correlation between TCCA and gender, TCCA and Kellgren-Lawrence(K-L) grade. RESULTS: All 100 patients successfully completed the operation and obtained satisfactory full-length X-rays in standing position. There was no significant difference in TL, MPTA and TCCA between bending group and non bending group(P>0.05). The outilier rate of force line in tibial bending group was 22.5%, and that in non bending group was 6.67%, the difference was statistically significant(P<0.05). The correlation study found that TCCA was strongly correlated with TBA(r=-0.702, P<0.01), weakly correlated with MPTA(r=0.311, P<0.01), and had no correlation with other parameters(P>0.05). CONCLUSION In patients with knee osteoarthritis undergoing total knee arthroplasty, tibial bending will lead to poor force line of tibial prosthesis. During operation, attention should be paid to osteotomy of proximal tibial vertical tibial mechanical axis and correct installation of prosthesis to avoid poor alignment of prosthesis.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/adverse effects* ; Female ; Humans ; Knee Joint/surgery* ; Knee Prosthesis/adverse effects* ; Male ; Middle Aged ; Osteoarthritis, Knee/surgery* ; Retrospective Studies ; Tibia/surgery*

BACKGROUND: The aim of this study was to evaluate causes of unstable total knee arthroplasty and results of revision surgery. METHODS: We retrospectively reviewed 24 knees that underwent a revision arthroplasty for unstable total knee arthroplasty. The average follow-up period was 33.8 months. We classified the instability and analyzed the treatment results according to its cause. Stress radiographs, postoperative component position, and joint level were measured. Clinical outcomes were assessed using the Hospital for Special Surgery (HSS) score and range of motion. RESULTS: Causes of instability included coronal instability with posteromedial polyethylene wear and lateral laxity in 13 knees, coronal instability with posteromedial polyethylene wear in 6 knees and coronal and sagittal instability in 3 knees including post breakage in 1 knee, global instability in 1 knee and flexion instability in 1 knee. Mean preoperative/postoperative varus and valgus angles were 5.8degrees/3.2degrees (p = 0.713) and 22.5degrees/5.6degrees (p = 0.032). Mean postoperative alpha, beta, gamma, delta angle were 5.34degrees, 89.65degrees, 2.74degrees, 6.77degrees. Mean changes of joint levels were from 14.1 mm to 13.6 mm from fibular head (p = 0.82). The mean HSS score improved from 53.4 to 89.2 (p = 0.04). The average range of motion was changed from 123degrees to 122degrees (p = 0.82). CONCLUSIONS: Revision total knee arthroplasty with or without a more constrained prosthesis will be a definite solution for an unstable total knee arthroplasty. The solution according to cause is very important and seems to be helpful to avoid unnecessary over-constrained implant selection in revision surgery for total knee instability.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/*adverse effects ; Female ; Humans ; Joint Instability/*etiology ; Knee Joint/*surgery ; Knee Prosthesis ; Male ; Middle Aged ; *Prosthesis Failure ; Reoperation ; Retrospective Studies

BACKGROUND: This study examined the clinical and radiologic mid-term results of patients treated by Oxford minimally invasive unicompartmental knee arthroplasty. METHODS: One hundred and eighty-eight knees of unicompartmental knee arthroplasties with Oxford Uni(R) in 166 patients (16 males and 150 females), which were performed between 2002 and 2005, were reviewed. The mean age was 65.3 years (range, 44 to 82 years) and the mean follow-up period was 79.8 months (range, 56 to 103 months). The preoperative diagnosis was osteoarthritis in 166 patients, osteonecrosis of the medial femoral condyle in 20 and chondrocalcinosis in 2. RESULTS: The mean Hospital for Special Surgery (HSS) knee score was 67.5 (range, 52 to 75) preoperatively and 89.9 (range, 85 to 100) at the final follow-up. The mean preoperative flexion contracture was 6.5degrees (range, 0 to 15degrees) and 0.8degrees (range, 0 to 5degrees) at the final follow-up. The mean full flexion increased from 135degrees (range, 90 to 150degrees) preoperatively to 150degrees (range, 140 to 165degrees) at the final follow-up. Active full flexion was possible within 2 postoperative months. The squatting and cross-leg postures were possible in 133 patients (80.1%) and 152 patients (91.6%) at the final follow-up. The mean tibiofemoral angle was improved from varus 1.5degrees to valgus 4.8degrees. Complications were encountered in 18 cases (9.5%). A bearing dislocation occurred in 10 cases (5.3%), tibial component loosening in 4 cases (2.1%), femoral loosening in 3 cases (1.6%) and lateral translation in 1 case (0.5%). The mean time for a bearing dislocation was 22.6 months (range, 3 to 70 months) postoperatively. Seven cases returned to the predislocation level of activity with the insertion of a thicker bearing and 3 cases converted to total knee arthroplasty. CONCLUSIONS: Minimally invasive unicompartmental knee arthroplasty with Oxford Uni(R) provided rapid recovery, good pain relief and excellent function suitable for the Korean lifestyle. In contrast, the high complication rates of Oxford Uni(R) encountered in the mid-term results suggested less reliability than total knee arthroplasty.
Adult ; Aged ; Aged, 80 and over ; *Arthroplasty, Replacement, Knee/adverse effects ; Female ; Humans ; Knee Joint/physiopathology/radiography ; *Knee Prosthesis ; Male ; Middle Aged ; Prosthesis Failure ; Range of Motion, Articular

Humans ; Arthroplasty, Replacement, Knee/adverse effects* ; Arthroplasty, Replacement, Hip/adverse effects* ; Reoperation ; Prosthesis-Related Infections ; Retrospective Studies

Periprosthetic joint infection (PJI) is the most difficult complication following total joint arthroplasty. Most of the etiological strains, accounting for over 98% of PJI, are bacterial species, with Staphylococcusaureus and Coagulase-negative staphylococci present in between 50% and 60% of all PJIs. Fungi, though rare, can also cause PJI in 1%-2% of cases and can be challenging to manage. The management of this uncommon but complex condition is challenging due to the absence of a consistent algorithm. Diagnosis of fungal PJI is difficult as isolation of the organisms by traditional culture may take a long time, and some of the culture-negative PJI can be caused by fungal organisms. In recent years, the introduction of next-generation sequencing has provided opportunity for isolation of the infective organisms in culture-negative PJI cases. The suggested treatment is based on consensus and includes operative and non-operative measures. Two-stage revision surgery is the most reliable surgical option for chronic PJI caused by fungi. Pharmacological therapy with antifungal agents is required for a long period of time with antibiotics and included to cover superinfections with bacterial species. The aim of this review article is to report the most up-to-date information on the diagnosis and treatment of fungal PJI with the intention of providing clear guidance to clinicians, researchers and surgeons.
Arthritis, Infectious/etiology* ; Arthroplasty, Replacement, Knee/adverse effects* ; Fungi ; Humans ; Prosthesis-Related Infections/therapy* ; Retrospective Studies

BACKGROUND: The clinical and radiological outcomes of revision total knee arthroplasty with a cemented posterior stabilized (PS), condylar constrained knee (CCK) or a fully constrained rotating hinge knee (RHK) prosthesis were evaluated. METHODS: This study reviewed the clinical and radiological results of 36 revision total knee arthroplasties with a cemented PS, CCK, and RHK prosthesis in 8, 25, and 13 cases, respectively, performed between 1998 and 2006. The mean follow-up period was 30 months (range, 24 to 100 months). The reason for the revision was aseptic loosening of one or both components in 15, an infected total knee in 18 and a periprosthetic fracture in 3 knees. The average age of the patients at the time of the revision was 65 years (range, 58 to 83 years). The original diagnosis for all primary total knee arthroplasties was osteoarthritis except for one case of a Charcot joint. All revision prostheses were fixed with cement. The bone deficiencies were grafted with a cancellous allograft in the contained defect and cortical allograft fixed with a plate and screws in the noncontained defect. A medial gastrocnemius flap was needed to cover the wound dehiscence in 6 of the 18 infected cases. RESULTS: The mean Knee Society knee score improved from 28 (range, 5 to 43) to 83 (range, 55 to 94), (p < 0.001) and the mean Knee Society function score improved from 42 (range, 10 to 66) to 82 (range, 60 to 95), (p < 0.001) at the final follow-up. Good or excellent outcomes were obtained in 82% of knees. There were 5 complications (an extensor mechanism rupture in 3 and recurrence of infection in 2 cases). Three cases of an extensor mechanism defect (two ruptures of ligamentum patellae and one patellectomy) were managed by the RHK prosthesis to provide locking stability in the heel strike and push off phases, and two cases of recurrent infection used an antibiotic impregnated cement spacer. The radiological tibiofemoral alignment improved from 1.7degrees varus to 3.0degrees valgus in average. Radiolucent lines were observed in 18% of the knees without progressive osteolysis. CONCLUSIONS: Revision total knee requires a more constrained prosthesis than primary total knee arthroplasty because of the ligamentous instability and bony defect. This short to midterm follow-up analysis demonstrated that a well planned and precisely executed revision can reduce pain and improve the knee function significantly. Infected cases showed as good a result as those with aseptic loosening through the use of antibiotics-impregnated cement beads and proper soft tissue coverage with a medial gastrocnemius flap.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/adverse effects/*methods ; Bone Transplantation ; Cementation ; Humans ; Knee Joint/radiography ; *Knee Prosthesis ; Middle Aged ; Osteoarthritis, Knee/surgery ; Prosthesis Design ; Prosthesis Failure ; Reoperation

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*

BACKGROUND: The authors report the results of preserving the infrapatellar branch of the saphenous nerve during unicompartmental knee arthroplasty to prevent lateral skin numbness. METHODS: All 100 cases had medial compartmental osteoarthritis and a minimally invasive technique had been used. The mean follow-up duration was two years and eight months (range, 24 to 42 months). RESULTS: The classification according to the location of this nerve was observed as either Mochida Type I with 76 cases (76%), Type II with 16 cases (16%), and unclassified type with 8 cases (8%). In Type I, the nerve was saved in 62 cases (82%), but could not be preserved in Type II because of the surgical procedure. These results showed that the mean distance from the joint line to the nerve of Type I was 9.13 mm (range, 4 to 15 mm) and the nerve passed inferiorly. CONCLUSIONS: This study showed the location of this nerve can be predicted ahead of the procedure, which will help preserve it during the surgery.
Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee/adverse effects/*methods ; Female ; Humans ; Hypesthesia/etiology/*prevention & control ; *Knee Prosthesis ; Male ; Middle Aged ; Osteoarthritis, Knee/surgery ; Skin/*innervation

This paper is aimed to focus on the joint prosthesis failure event, to collect the statistic data about the failure of artificial joints issued by authoritative organizations at home and aboard, and to compare the functions of different types of the artificial joints. We generalized and compared current study analyzing the failure reason and type of joint prosthesis, and categorized the failure events according to the failure occurring time, i. e. short-term, medium-term and long-term. This paper could be helpful for improving and summarizing of artificial joint replacement surgery, and could put forward the requirements for the future artificial joints.
Arthroplasty, Replacement ; adverse effects ; statistics & numerical data ; Arthroplasty, Replacement, Hip ; adverse effects ; statistics & numerical data ; Arthroplasty, Replacement, Knee ; adverse effects ; statistics & numerical data ; Humans ; Joint Prosthesis ; Prosthesis Failure ; etiology