The results at ten years of the Insall-Burstein II total knee replacement

Impact of implant positions in total knee arthroplasty on the postoperative knee kinematics of tibial rotation

Introduction

In total knee arthroplasty (TKA), the implant positions and knee kinematics, as well as the manifestation of medial pivot motion, play pivotal roles in determining postoperative clinical outcomes. The purpose of the current study was to analyze the correlation between knee kinematics, which was measured during TKA and implant positions derived using computed tomography (CT) examination after TKA.

Methods

This study comprised 64 patients (76 knees) who underwent primary TKA between 2015 and 2022. A navigation system was used in TKA procedures, and intraoperative knee kinematics were automatically calculated with it. Utilizing three-dimensional evaluation software, positioning of implants was quantified with CT images taken pre- and post-operatively. Multiple regression analyses were employed to explore the impact of femoral component position (FP) and tibial component position (TP) on knee kinematics, focusing on the extent of tibial rotational motion (TRM) during passive knee motion.

Results

FP affected TRM between knee extension and 90° flexion (p = 0.003, 95 % confidence interval [CI]: 0.315-1.384) and between knee extension and full flexion (p = 0.0002, 95 % CI: 0.654-1.844) after TKA. FP in internal rotation positively affected internal TRM after TKA. TP was not associated with TRM.

Conclusions

Findings of the current study suggest that FP in internal rotation positively impacts knee kinematics after TKA.

Efficacy of Cal-Cemex as bone substitute for tibial plateau fractures

BACKGROUND

Various factors influence treatment and outcomes in tibial plateau fractures. Bone defects are among them. Many materials have been proposed to address this problem: allograft, bone-cements and various bone substitutes (BSM). Cal-Cemex (β-tricalciophosphate and polymethylmethacrylate) is a new hybrid bi-component BSM. A retrospective multicenter study was conducted based on the clinical experience of three European Hospitals, to demonstrate its clinical effectiveness, versatility and safety.

MATERIALS AND METHODS

From December 2016 to March 2022, 45 displaced tibial plateau fractures were treated with internal fixation and augmentation using Cal-Cemex. The average age was 55.9 years. According to Schatzker classification, we included 13 type II, 24 type III, 3 type V and 4 type VI fractures. The postoperative follow-up (FU) consisted of clinical and radiological examinations at 6 and 12 weeks and 1 year after surgery. A CT scan was performed preoperatively and 1 year after surgery. Full weight bearing was permitted after less than 6 weeks. Clinical data were collected from patient charts, while functional data were evaluated using the Rasmussen knee function score, the KOOS score and the Hospital for Special Surgery knee rating score (HSS), to evaluate the range of motion, axis and functionality of the knee.

RESULTS

The average FU was 42.8 months. CT scans taken at 1 year demonstrated a good surface osteointegration without radiolucent lines or osteolysis with good evidence of interdigitation and even bone ingrowth. At 1-year FU, the mean Rasmussen score was 24.7, the mean KOOS score was 90.7 and the mean HSS was 89.9 and the average full weight-bearing period 34.9. No patients had hardware failure or fracture secondary displacement.

DISCUSSION

Cal-Cemex combines biological features and good mechanical performances. It guarantees biocompatibility and osteoconductivity, although it is not fully reabsorbable; β-tricalciophosphate component gives macro- and microporosity that allow fluids to penetrate inside the material, to stimulate bone ingrowth.

CONCLUSIONS

The study suggests that Cal-Cemex is an option for tibial plateau fractures, where augmentation and support are necessary for early full weight bearing. The absence of major complications, ease of application, the possibility to cut and perforate this material support its extensive use in bone augmentation for trauma cases.

Relationship between the Femoral and Tibial Component Positions and Postoperative Knee Range of Motion after Posterior-Stabilized Total Knee Arthroplasty in Varus-Aligned Knees

This study aimed to evaluate the relationship between the femoral and tibial component positions and postoperative knee range of motion after posterior-stabilized total knee arthroplasty (TKA). Forty-four patients (48 knees in total: 9 men, 9 knees; 35 women, 39 knees) who underwent posterior-stabilized TKA using a navigation system were included. The femoral and tibial component positions were measured from the preoperative and postoperative computed tomography data with three-dimensional evaluation software. We investigated the relationship between the knee range of motion, including extension restriction and maximum flexion angles at 2 years postoperatively, and the femoral and tibial component positions. Patients with knee extension restriction of 10° or more at 2 years postoperatively showed greater posterior flexion position of the tibial component than those with knee extension restriction less than 10° (6.2° and 3.9°, respectively, p=0.018). The postoperative knee flexion angle was positively associated with the internal rotational position of the femoral component (p=0.032, 95% confidence interval: 0.105-2.178). Patients with a knee flexion angle more than 120° at 2 years postoperatively had greater internal rotational position of the femoral component than those with 120° or less (5.2° and 1.5°, respectively, p=0.002). In conclusions, after posterior-stabilized TKA, the postoperative knee extension restriction angle was associated with the posterior flexion position of the tibial component, and the knee flexion angle was positively related to the internal rotational position of the femoral component.

Reverse traction with Kirschner wires and bilateral external fixation device combined with minimally invasive plate oseoynthesis technique for tibial plateau fractures of type Schatzker V and VI

PURPOSE

Complex bicondylar tibial plateau fracture (TPF) has always been a tricky problem for surgeons. We created a novel external device used intraoperatively consisting of Kirschner wires, and combined with minimally invasive plate oseoynthesis (MIPO) technique to treat complex bicondylar TPFs, and the clinical effect and feasibility were further evaluated.

METHODS

From March 2016 to February 2021, 49 cases (29 males and 20 females) were identified as bicondylar TPF, the mean age 47.2 (27-69). All patients adopted the device and MIPO technique. A series of score, complications, and radiographs in the follow-up period, from three months, six months, one year, and two years and the last follow-up, were recorded, from visual analogue score (VAS), hospital for special surgery (HSS), and Short-Form 36 (SF-36), containing physical (PCS) and mental (MCS), and Rasmussen score.

RESULTS

Forty-seven patients showed good functional recovery. No patients were lost, mean follow-up time was 28.17 ± 2.81 (24.2-35.4) months. Operation time was 89.80 ± 13.46 (58-110) min. At the last follow-up, VAS was 1.3 ± 0.92 (0-4), HHS was 93.10 ± 2.63 (89-99), PCS was 49.20 ± 7.40 (38-65), and MCS was 50.08 ± 4.77 (43-62). Complications were as follows: cutaneous necrosis (3, 6%), asymptomatic arthritis (3, 6%), symptomatic arthritis (1, 2%), and deep venous thrombosis (1, 2%). Mean fracture healing time was 11.82 ± 1.5 (10-15.4) weeks. All patients got recovery without extra surgery and removed the implants at 12.85 ± 0.76 (11.2-15.4) months.

CONCLUSION

Temporary traction device of bilateral external fixator combined with MIPO technique was simple and convenient, with a smaller soft-tissue damage, an easier operational approach, and its worth being promoted.

Mechanical complications after total knee arthroplasty

INTRODUCTION

With the increasing demand for total knee arthroplasty (TKA) and the burden of revision TKA on the healthcare system, as well as the quality of life implications for patients, it is extremely important for surgeons to be able to anticipate and prevent TKA mechanical complications. Surgeons must be familiar with the different causes and mechanisms of TKA complications so that they can properly treat patients with failed TKAs and better avoid these complications.

AREAS COVERED

This review addresses TKA mechanical complications and provides context for the topic. A detailed review of surgical factors, implant factors, and patient factors that contribute to mechanical complications after TKA is provided. All of the literature cited in this review was gathered from the PubMed online database using different keywords based on the section of the manuscript.

EXPERT OPINION

As surgeons and engineers solve certain issues in TKA, new challenges will inevitably arise. We must continue to push forward and innovate from both a surgical technique and implant design perspective.

Implant survival of 3rd-condyle and post-cam posterior-stabilised total knee arthroplasty are comparable at follow-up > 10 years: a systematic review

PURPOSE

To summarise the literature on 3rd-condyle total knee arthroplasty (TKA) designs and compare their survival rates to those of post-cam TKA designs. The null hypothesis was that 3rd-condyle TKAs would have equivalent survival rates compared to contemporary post-cam TKAs.

METHODS

An electronic literature search for Level I-V studies was independently conducted by two researchers using Medline^® and Web of Science for studies published between January 1984 and October 2020 that specifically reported on rates of implant survival and complications, joint kinematics, clinical outcomes, and radiographic outcomes of 3rd-condyle TKA. The methodological quality of clinical studies was assessed according to the Downs and Black Quality Checklist for Health Care Intervention Studies, and for in vitro and in silico studies according to the Joanna Briggs Institute (JBI) tool for assessing analytical cross-sectional studies. Findings extracted for each TKA design were presented as reported and synthesised narratively. Survival rates at 5, 10 and > 10 years of 3rd-condyle TKA designs were graphically compared to rates of post-cam TKA designs published in joint registries.

RESULTS

A total of 38 studies were identified that reported on kinematics, clinical outcomes, radiographic alignment, and rates of complications and survival. Mean survival rates ranged from 96 to 98% at 5 years, 78-100% at 5-10 years, and 86-99% at > 10 years for 3rd-condyle PS TKAs. Mean survival rates ranged from 93 to 98% at 5 years, 89-99% at 5-10 years, and 88-95% at > 10 years for post-cam PS TKAs.

CONCLUSION

Implant survival rates of 3rd-condyle TKAs are comparable to those of post-cam TKAs at follow-up > 10 years. When compared to post-cam PS TKA, 3rd-condyle designs offer an alternative for younger and more active patients when considering the added benefits of a lowered point-of-contact and larger congruent contact area at the intercondylar tibial sulcus, that reduce risks of loosening and component wear.

LEVEL OF EVIDENCE

V.

A Review of Clinical Pathway Data of 1663 Total Knee Arthroplasties in a Tertiary Institution in Singapore

Introduction and Objectives: A total knee arthroplasty (TKA) clinical pathway database has been used in our institution since the year 2000. The primary aim of this study was to review the patient epidemiology, postoperative complications and factors influencing hospital length of stay following TKA. The clinical outcomes and cost-savings between elective and same day admissions for TKA patients were also reviewed. Materials and Methods: The study cohort retrieved from the database comprised 1371 patients (1663 knees) who underwent total knee replacement over a 6-year time period. The following variables were reviewed: epidemiological data, admission data (elective admission [EA] versus same day admission [SDA]), hospital length of stay (LOS), and complication rates. Results: The mean age of patients undergoing TKA is 65.2 years (range, 22 to 90). Osteoarthritis was the main surgical indication in 96% of the study cohort. Overall, there was a gradual decline in the hospital length of stay for the study cohort for the 6-year time period. The overall complication rate was 2% and the 3 most common complications were deep vein thrombosis, pulmonary embolism and urinary tract infection. Conclusion: With an increasing elderly population there will be an annual increase in the number of TKAs. In our local population TKAs are performed primarily for the Chinese female in the 7th decade. The overall complication rate of TKA remains low with a mortality rate of <1%. Key words: Complications, Epidemiology, Total knee arthroplasty

High incidence of loosening of the femoral component in legacy posterior stabilised-flex total knee replacement

We have examined the results obtained with 72 NexGen legacy posterior stabilised-flex fixed total knee replacements in 47 patients implanted by a single surgeon between March 2003 and September 2004. Aseptic loosening of the femoral component was found in 27 (38%) of the replacements at a mean follow-up of 32 months (30 to 48) and 15 knees (21%) required revision at a mean of 23 months (11 to 45). We compared the radiologically-loose and revised knees with those which had remained well-fixed to identify the factors which had contributed to this high rate of aseptic loosening. Post-operatively, the mean maximum flexion was 136 degrees (110 degrees to 140 degrees) in the loosened group and 125 degrees (95 degrees to 140 degrees) in the well-fixed group (independent t-test, p = 0.022). Squatting, kneeling, or sitting cross-legged could be achieved by 23 (85%) of the loosened knees, but only 22 (49%) of the well-fixed knees (chi-squared test, p = 0.001). The loosened femoral components were found to migrate into a more flexed position, but no migration was detected in the well-fixed group. These implants allowed a high degree of flexion, but showed a marked rate of early loosening of the femoral component, which was associated with weight-bearing in maximum flexion.

The posterior cruciate ligament-preserving total knee replacement: do we 'preserve' it? A radiological study

Our aims were to map the tibial footprint of the posterior cruciate ligament (PCL) using MRI in patients undergoing PCL-preserving total knee replacement, and to document the disruption of this footprint as a result of the tibial cut. In 26 consecutive patients plain radiography and MRI of the knee were performed pre-operatively, and plain radiography post-operatively. The lower margin of the PCL footprint was located a mean of 1 mm (-10 to 8) above the upper aspect of the fibular head. The mean surface area was 83 mm(2) (49 to 142). One-third of patients (8 of 22) had tibial cuts made below the lowest aspect of the PCL footprint (complete removal) and one-third (9 of 22) had cuts extending into the footprint (partial removal). The remaining patients (5 of 22) had footprints unaffected by the cuts, keeping them intact. Our study highlights the wide variation in the location of the tibial PCL footprint when referenced against the fibula. Proximal tibial cuts using conventional jigs resulted in the removal of a significant portion, if not all of the PCL footprint in most of the patients in our study. Our findings suggest that when performing PCL-retaining total knee replacement the tibial attachment of the PCL is often removed.

Ten-year survival analysis of the PFC total knee arthroplasty--a surgeon's first 99 replacements

Ninety-seven patients with 99 total knee arthroplasties were operated on by a surgeon in the first 3 years of his surgical career. Complete survival data were available for all 99 knees. The cases were reviewed at a minimum of 10 years after their initial operation, but as 37 patients had died before reaching 10 years, the average follow-up was 8 years 8 months with a maximum of 12 years 4 months. Ninety-one patients had osteoarthritis, five had rheumatoid arthritis, and three had juvenile chronic arthritis. No patients were lost to follow-up. Four required revision. The 10-year survival rate, using revision for all causes as an end-point, was 94.96%. The survival rate for aseptic loosening was 97.04%. The survival rate for loose joints that had not been revised was 94.13%. Three of the four revisions occurred in the first 6 patients operated upon, suggesting there may be a learning curve for surgeons at this stage in their career.

Total knee replacement in haemophilic arthropathy

The results of primary total knee replacement performed on a group of haemophiliac patients in a single institution by the same surgeon using the same surgical technique and prosthesis are reported.

A total of 35 primary replacements in 30 patients were carried out between 1996 and 2005 and were reviewed retrospectively. The mean age of the patients was 31 years (24 to 42) and the mean follow-up was for 7.5 years (1 to 10). There were 25 patients with haemophilia A and five with haemophilia B. The HIV status and CD4 count were recorded, and Knee Society scores determined. Two patients had inhibitors to the deficient coagulation factor.

There were no early wound infections and only one late deep infection which required a two-stage revision arthroplasty, with a good final result. The incidence of infection in HIV-positive and negative patients was thus similar. One knee in a patient with inhibitor had excessive bleeding due to a pseudoaneurysm which required embolisation. The results were excellent in 27 knees (77%), good in six (17%) and fair in two (6%). The survival rate at 7.5 years taking removal of the prosthesis for loosening or infection as the end-point was 97%.

The mechanical survival of total knee replacements in haemophiliacs is very good. Our results confirm that this is a reproducible procedure in haemophilia, even in HIV-positive patients with a CD4 count > 200 mm3 and those with inhibitors. Our rate of infection was lower than previously reported. This could be due to better control of the HIV status with highly active anti-retroviral therapy and the use of antibiotic-loaded cement.

A hydroxyapatite-coated Insall-Burstein II total knee replacement

We report the clinical and radiographic outcome of a consecutive series of 138 hydroxyapatite-coated total knee replacements with a mean follow-up of 11 years (10 to 13). The patients were entered into a prospective study and all living patients (76 knees) were evaluated. The Hospital for Special Surgery knee score was obtained for comparison with the pre-operative situation. No patient was lost to follow-up. Radiographic assessment revealed no loosening. Seven prostheses have been revised, giving a cumulative survival rate of 93% at 13 years. We believe this to be the longest follow-up report available for an hydroxyapatite-coated knee replacement and the first for this design of Insall-Burstein II knee.

Long-term followup after mobile-bearing total knee replacement

Clinical and radiographic analyses and survivorship were done on the initial cementless series of 309 posterior cruciate-retaining meniscal-bearing and rotating-platform New Jersey LCS total knee replacements followed up for 10 to 20 years (mean, 12.4 years). Clinical results in patients surviving at least 10 years using a strict knee scoring scale were similar for posterior cruciate ligament-retaining and posterior cruciate ligament-sacrificing designs. Good to excellent results were seen in 97.9% of primary posterior cruciate-retaining-bearing prostheses and in 97.9% of primary rotating-platform prostheses. Radiographic analysis of minimum 10-year followup radiographs showed generally stable fixation of all components with gross migration seen in one tibial component (0.6%) in a patient with a failed high tibial osteotomy. Significant osteolysis was present requiring bearing exchange and bone grating in three patients with cementless rotating-platform prostheses (1.8%) who had multiple knee surgeries at an average of 10.2 years from the index surgery. Survivorship of the primary cementless posterior cruciate-retaining meniscal-bearing prostheses with an end point of revision for any mechanical reason was 97.4% at 10 years and 83% at 16 years; using an end point of a poor clinical knee score, the survivorship was 98.9% at 10 and 16 years, respectively. Survivorship of the primary cementless rotating-platform prostheses with end points of revision for any mechanical reason or a poor clinical knee score was 98.3% survivorship at 10 and 18 years, respectively. In the current study, no cementless rotating-bearing patella loosened, fractured, or dissociated in patients without prior knee surgery although one cementless rotating-bearing patella (0.6%) in a patient who had multiple knee surgeries wore through the inferior marker wire after 10.8 years, causing metallosis that required revision.

Detecting bacterial colonization of implanted orthopaedic devices by ultrasonication

Glycocalyx-producing bacteria have been observed on orthopaedic devices that were removed for reasons other than infection. It has been suggested that the bacteria adhere to foreign surfaces within a biofilm and elude standard culture techniques. The authors adapted previously used ultrasonication protocols that disrupt the surface biofilm before culturing removed orthopaedic devices from patients without clinical evidence of infection. Patients having revision total joint arthroplasty of the hip or knee who lacked current or prior clinical evidence of infection were studied prospectively. During surgery, the femoral component and a corresponding control femoral implant were placed in separate sterile bags of saline. The implant and saline combination was placed in an ultrasonication bath for 30 minutes at 60 Hz. The saline solution was passed through a 0.45-microm pore filter, and the filter residue was cultured on sheep blood agar. None of the 21 implants yielded positive culture on routine microbiologic testing. However, using the ultrasonication protocol, a coagulase-negative Staphylococcus grew from one of the removed implants. Numerous total joint implant failures that are attributed to aseptic loosening may be a result of subclinical infection from bacteria within a biofilm. The current study supports the concept that biofilm-protected bacterial colonization of implants may occur without overt signs of infection and ultrasonication can be used to enhance identification of these bacteria.

Scoring systems in total knee arthroplasty

For assessment of total knee arthroplasty outcome, various scoring systems have been introduced. The current study assessed the interobserver correlation of four commonly used total knee arthroplasty outcome scores. One hundred eighteen total knee arthroplasties were investigated by two independent observers, using the Hungerford score, the Hospital for Special Surgery score, the Knee Society score, and the Bristol score. Each score consisted of three subscores: pain, knee, and function. For the highest interobserver correlation was computed for the Bristol score (interobserver correlation coefficient, 0.88). For knee range of motion, flexion contracture, and extension lag there was high interobserver correlation (interobserver correlation coefficient > 0.8 each). For walking distance and walking aids, there also was a high interobserver correlation (interobserver correlation coefficient > 0.7 each). For clinical assessment of total knee arthroplasty, pain should be measured on a four-step system, the knee should be assessed by measurement of range of motion, extension lag, and flexion contracture, and function should be measured on a separate score assessing walking distance and walking aids.

Revision total knee arthroplasty using large distal femoral augments for severe metaphyseal bone deficiency: a preliminary study

Managing severe structural femoral metaphyseal bone loss in revision total knee arthroplasty is a challenging problem facing the revision knee surgeon. This study assesses the use of large (30 mm) metal distal femoral augments to compensate for severe bone deficiencies. Hospital for Special Surgery scores, Knee Society scores, and range of motion improved after implantation of femoral components with 30-mm distal femoral augments. There was no radiographic evidence of loosening, and no implants had been revised at mean 37-month follow-up. This appears to be an acceptable technique based on the intermediate-term results.

Component rotation and anterior knee pain after total knee arthroplasty

All patients undergoing cruciate-retaining primary total knee arthroplasty for degenerative osteoarthritis at one center were studied prospectively. Clinical and radiographic followup was obtained at a minimum 5 years in 102 knees in 73 patients. Patients were asked specifically about the presence of the pain in the anterior aspect of the knee in the vicinity of the patella and rated the severity of the pain on a visual analog scale. Significant anterior knee pain rating at least 3 of 10 on the visual analog scale was present in 16 knees (13 patients). Eleven patients with 14 symptomatic knees agreed to undergo computed tomography scanning to accurately determine the rotation of the tibial and femoral components. The epicondylar axis and tibial tubercle were used as references using a previously validated technique. A control group of 11 asymptomatic patients (14 knees), matched for age, gender, and length of followup also underwent computed tomography scanning. All patients in both groups had normal axial alignment. There was a highly significant difference in tibial component rotation between the two groups with the patients with anterior knee pain averaging 6.2 degrees internal rotation compared with 0.4 degrees external rotation in the control group. There also was a significant difference in combined component rotation with the patients with anterior knee pain averaging 4.7 degrees internal rotation compared with 2.6 degrees external rotation in the control group. There was no significant difference in the degree of radiographic patellar tilt or patellar subluxation between the two groups. Patients with combined component internal rotation were more than five times as likely to experience anterior knee pain after total knee arthroplasty compared with those with combined component external rotation. Component malrotation is a significant factor in the development of anterior knee pain after total knee arthroplasty.

An algorithm for the posterior cruciate ligament in total knee arthroplasty

The fate of the posterior cruciate ligament in primary total knee arthroplasty is controversial. An algorithmic approach is presented that is based on pathologic criteria for evaluating and treating patients with primary total knee arthroplasty that will aid in the posterior cruciate ligament decision-making process, producing more predictable procedures and outcomes. A consecutive series of the first 120 patients (171 knees) who had primary posterior cruciate-retaining arthroplasty and the first 120 patients (180 knees) who had primary posterior-stabilized arthroplasty with a minimum 5-year followup in which the Maxim Complete Total Knee System and the algorithmic approach were used were compared. No statistically significant differences in outcome between the groups were observed. Among the patients who had posterior cruciate-retaining arthroplasty, no revisions attributable to aseptic loosening have been reported at an average followup of 6.39 years. The average followup Knee Society total score was 162.16 points, with 91 (54.8%) knees having excellent outcome ratings. No revisions attributable to aseptic loosening have been reported among the patients who had posterior-stabilized arthroplasty at an average followup of 5.98 years. The average followup Knee Society total score was 158.05 points, with excellent outcome ratings reported in 96 (54.9%) knees. The use of a standardized algorithm has streamlined the treatment of patients having primary total knee arthroplasty, consistently providing excellent clinical results when either retaining or sacrificing the posterior cruciate ligament.

Tibiofemoral conformity and kinematics of rotating-bearing knee prostheses

Increasing tibiofemoral articular conformity theoretically increases articular contact area and reduces contact stresses in total knee arthroplasty. Fixed-bearing knee designs possess relatively low tibiofemoral conformity, in part to allow tibiofemoral rotation without generating excessive stresses at the articulation or the implant-bone interface. This study analyzed knee kinematics of mobile-bearing designs in a closed chain dynamic knee extension model in posterior cruciate-retaining design with high- and low tibiofemoral conformity and posterior cruciate-substituting designs with and without rotational constraint. Overall, for all conditions, the mobile-bearing insert rotated with the femur in the presence of tibiofemoral axial rotation. In addition, the correlation of bearing rotation with femoral rotation was stronger for the high-conformity and rotationally-constrained designs than for the low-conformity designs and strongest for the posterior cruciate-retaining high-conformity condition. Changes in conformity or rotational constraint did not appear to affect femoral roll back, tibiofemoral axial rotation, or varus-valgus angulation. The results suggest that mobile-bearing inserts rotate with the femur and increasing conformity or rotational constraint in mobile-bearing design knee prostheses does not affect knee kinematics adversely, at least under closed chain knee extension conditions in vitro.