Primary TKA in patients with major deformities and ligament laxities: promising results of an intermediate constrained implant at mid-term follow-up

Excellent 2-Year Outcomes of a Midlevel Constrained Liner Used in Stemless Primary TKA

Introduction

Instability after total knee arthroplasty (TKA) remains a leading cause of revision TKA and can lead to patient dissatisfaction. While many companies have developed midlevel constrained (MLC) polyethylene inserts in primary TKAs, there is little data on their outcomes.

Purpose

We sought to analyze short-term outcomes including survivorship, rates of manipulation under anesthesia (MUA), and improvements in patient-reported outcome measures (PROMs) preoperatively to postoperatively in one design of MLC TKA.

Methods

We prospectively followed consecutive primary TKA patients who received constrained inserts (Journey II or Legion Genesis II, Smith and Nephew) from 5 surgeons, 2019 to 2020, at a single academic institution. We analyzed revision-free survivorship, MUA rates, and PROMs, preoperatively to postoperatively.

Results

A total of 356 patients were included with a mean age of 64 years; 49% were male and the mean body mass index (BMI) was 31 kg/m2. Sixteen patients (4.5%) underwent MUA and 3 patients (0.8%) underwent revision. Two patients underwent polyethylene exchange and patellar resection for patellar loosening. One patient underwent liner exchange for instability. The 2-year revision-free survivorship was 98.5% (95% confidence interval [CI]: 96.6%-100%). Survivorship free from revision for tibial or femoral aseptic loosening was 100% at 2 years. The 2-year survivorship free from MUA was 92.3% (95% CI: 88.6%-96.1%). The mean Knee Osteoarthritis and Injury Outcomes Score Joint Replacement (KOOS JR) was 81 at 2 years follow-up, while the Lower Extremity Activity Score (LEAS) score was 10.5.

Conclusion

At a mean of 3 years follow-up, 2 types of MLCs used in primary TKA were associated with a low rate of early revision, low rate of MUA, and reliable improvement in functional outcomes. These MLCs were not associated with early loosening or unique failure modes.

The use of an imageless robotic system in revision of unicompartmental knee arthroplasty

PURPOSE

The application of robotics in revision arthroplasty particularly from unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA), is underexplored. The purpose of this study is to describe the surgical technique of an imageless robotic system used in the revision of UKA to TKA and to evaluate short- to mid-term outcomes.

METHODS

This prospective study includes 35 patients treated from May 2020 to July 2023. Demographic data of the patients were gathered and the reasons for needing revision surgery were assessed. All patients were clinically evaluated preoperatively and at the final follow-up of 31.3 ± 12.1 months, using the Western Ontario and McMaster Universities Arthritis Index (WOMAC), Oxford Knee Score (OKS), Forgotten Joint Score (FJS-12), Numerical Rating Scale (NRS) and range of motion (ROM). Additionally, a radiographic evaluation was performed, and implant survival was assessed by analyzing complications at final follow-up.

RESULTS

In 88.6% of the patients, a primary Posterior Stabilized (PS) or Constrained Posterior Stabilized prosthetic implant was used, with 11.4% of patients requiring a varus-valgus constraint implant. In 71.4% of the cases, a thinnest size liner of 10 mm was used. The use of the robotic system was never aborted for any reason. At final follow-up, the implant survival rate was 97.14%. Average OKS increased from 31.4 ± 9.4 to 41.5 ± 4.3, FJS-12 from 47.3 ± 19.3 to 80.7 ± 8.9; WOMAC at final follow-up was 17.8 ± 8.7, from 53.5 ± 21.3 preoperatively. Analyzing ROM, NRS and patient-reported outcome measures, there were significant differences in each parameter between prerevision surgery and final follow-up.

CONCLUSIONS

This study highlights that in a cohort of patients undergoing robotic-assisted conversion from UKA to TKA, the use of an imageless procedure incorporating intraoperative bone morphing and alignment based on a functional philosophy has proven to be safe and has yielded excellent clinical and radiographic outcomes.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

A novel grid-assisted pie-crusting technique for achieving soft tissue balance in total knee arthroplasty

Background

To evaluate the effectiveness of a novel grid-based pie-crusting technique for soft tissue release at different locations of the medial collateral ligament (MCL) during total knee arthroplasty (TKA).

Methods

Twelve fresh-frozen cadaveric knee joints were dissected. A novel grid was designed to cover the entire surface of the MCL. The specimens were divided into two groups: Group A, where only the central portion of the ligament underwent pie-crusting release, and Group B, where selective release targeted the femoral and tibial attachment points of the MCL. Mechanical testing was conducted via a Shimadzu AG-X precision instrument. Each group underwent twelve punctures, and data were collected to calculate deformation and stiffness metrics. The mean elongation and stiffness values were analyzed, and regression analysis was performed to evaluate correlations between the number of punctures and changes in elongation and stiffness.

Results

No significant differences in initial stiffness were observed between the two groups (P = 0.42). Following 12 punctures, the stiffness decreased by 6.47 ± 4.06 N/mm in Group A and 1.08 ± 1.32 N/mm in Group B (P = 0.006). Despite this disparity in stiffness reduction, no significant differences in MCL elongation were observed between the groups. Group A demonstrated an elongation of 0.171 ± 0.180 mm, whereas Group B exhibited an elongation of 0.164 ± 0.123 mm (P = 0.47). A linear relationship was identified between stiffness reduction and the number of punctures (R 2 = 0.61 ± 0.29), as well as between ligament elongation and the number of punctures (R 2 = 0.89 ± 0.09).

Conclusion

The grid-assisted pie-crusting technique, which uniformly covers the MCL, enables precise and controlled soft tissue release. This approach provides valuable insights for clinicians performing MCL release during TKA, facilitating improved soft tissue balance and potentially enhancing surgical outcomes.

International, consensus-based, indications and treatment options for knee arthroplasty in acute fractures around the knee

BACKGROUND

In the landscape of knee-related health issues there has been a notable shift in treatment protocols. Nowadays, there is a growing trend toward primary total knee arthroplasty (TKA) in the event of periarticular knee fractures. A review of the literature on TKA in acute knee fractures has been done in order to provide scientific evidence to the four statements submitted for voting to the members of the European Knee Society (EKS).

MATERIALS AND METHODS

A literature review has been performed around four topics of TKA in acute knee fractures, specifically: 1) The indications for TKA in acute knee fractures are undoubtful and clear; 2) Pre-existing osteoarthritis is not mandatory for the indication of TKA in acute fractures, while age, co-morbidities and type of fracture are; 3) A series of established criteria with scores to give indication for TKA (approved algorithm) is needed; and 4) This (complex) surgery must be performed in referral centers with all technical options and specific peri-operative management and post-operative care.

RESULTS

The panel of experts therefore believes that the indications cannot be considered undoubtful and clear. According to the literature up to the time of the consensus vote, there was no objective method for deciding on the treatment to offer the patient (Agree: 34.1%, Disagree: 61%, Abstain: 4.9%). It emerges that there are no mandatory conditions for the treatment of acute knee fractures with TKA (Agree: 32.3%, Disagree: 51.6%, Abstain: 16.1%). However, there are several characteristics to consider for a multifactorial evaluation rather than being limited to a single condition. While the consensus has highlighted a need for a scoring system to guide surgical decisions in periarticular knee fractures (Agree: 88.24%, Disagree: 8.82%, Abstain: 2.94%), research in the literature has confirmed that, to date, no validated algorithm exists. After the vote, a score was proposed, which requires validation. Although the panel of experts does not deem it necessary for this surgery to be reserved for reference centers (Agree: 32.35%, Disagree: 50%, Abstain: 17.65%), literature suggests that it is crucial that before undertaking knee arthroplasty in the setting of an acute fracture around the knee, the orthopedic surgeon is confident with all the necessary skills for a complex intervention that requires advanced knowledge and practical competence in osteosynthesis and revision TKA.

CONCLUSION

This discussion on the questions voted by the panel of experts has allowed for an in-depth exploration of a topic of interest, assessing indications, contraindications, types of possible treatment, and the critical aspects to consider when treating an acute fracture around the knee with a prosthesis. It is important to consider that the choice must be carefully weighed, evaluating the risks and benefits, with an increasingly need for a scoring system for selecting the most appropriate treatment.

Long term outcomes following tibial plateau fracture fixation and risk factors for progression to total knee arthroplasty

INTRODUCTION

Tibial plateau fractures are complex, peri-articular fractures that can have poor outcomes resulting in conversion to total knee arthroplasty (TKA). This study evaluates the 10-year survival of tibial plateau fractures treated with open reduction and internal fixation and identifies risk factors associated with conversion to TKA.

METHODS

This retrospective cohort study evaluates the outcomes of 126 patients undergoing tibial plateau ORIF from January 2011 to December 2012 at Glasgow Royal Infirmary. As well as patient factors, radiographic assessments were analysed including the degree of articular depression, medial proximal tibial angle, and femoral width ratio pre-operatively, peri-operatively and at the time of union. Patients requiring further surgical intervention, including TKA, were evaluated further.

RESULTS

A bell-shaped distribution of patient age was observed. Schatzker II fractures were most prevalent (48%). Pre-operative articular depression averaged 6.9 mm ranging from 0.0 - 36.0 mm. Operative reduction was generally satisfactory (mean articular depression 1.3 mm, femoral width 0.96, mPTA 89.6⁰), with 82% achieving an anatomical reduction. 12 patients (9.3%) required TKA during follow-up with Kaplan-Meier calculated as 91.9% at 5 years and 87.4% at 10 years. Articular depression > 4 mm (HR = 16.2), femoral width ratio > 1.05 (HR = 14.7) and age > 50 years (HR = 4.2) at time for fracture union were independently associated with progression to TKA.

CONCLUSION

9.3% of patients required TKA within 10 years of tibial plateau ORIF, Kaplan Meier 10-year survivorship was 87.4%. Joint depression and increased tibial width at time of union and age were independent risk factors associated with need for TKA. Particular care must be taken during operative intervention to ensure adequate reduction to lower this risk.

Isolated aseptic loosening in total knee arthroplasty: a comprehensive 10-year review of partial vs. total component revisions

BACKGROUND

In total knee arthroplasty (TKA), isolated aseptic loosening (IAL) requires the replacement of prosthetic components, with ongoing debate regarding the effectiveness of partial component revision (PCR) compared to total component revision (TCR). This study aims to compare implant survival and surgical outcomes between PCR and TCR in the context of IAL.

METHODS

This retrospective study analyzed data from 285 patients who underwent revision TKA for IAL between January 2000 and December 2013. After applying exclusion criteria, 112 patients were included in the analysis-60 undergoing TCR and 52 undergoing PCR.

RESULTS

PCR was associated with shorter operative times and hospital stays compared to TCR, alongside significant differences in the choice of revision prostheses. Although the prosthesis failure rates were comparable between the groups (13.6% for TCR and 18.33% for PCR), significant risk factors for failure were identified, including a canal filling ratio (CFR) below 0.8 and a discrepancy over 0.2 between CFR views. However, no significant differences in overall survivorship were observed between the groups.

CONCLUSIONS

Both PCR and TCR provide similar survival rates and clinical outcomes for managing IAL in TKA. PCR provides advantages in terms of surgical efficiency and patient recovery, while reducing the need for more constrained prosthetic solutions. The study identifies CFR as a critical predictor of prosthesis failure, highlighting the importance of detailed preoperative planning and implant selection. These findings contribute valuable insights for improving revision strategies in IAL, enhancing surgical outcomes in TKA.

LEVEL OF EVIDENCE

III.

Comparison of early curative effects of lateral unicompartmental knee arthroplasty with total knee arthroplasty and the legacy constrained condylar knee arthroplasty in the treatment of isolated lateral osteoarthritis: a single-center retrospective study

BACKGROUND

Aims of this study were to compare the functional and radiographic results, perioperative complication after lateral unicompartmental knee arthroplasty (LUKA) with total knee arthroplasty (TKA) and the legacy constrained condylar knee (LCCK) arthroplasty for the treatment of lateral compartmental knee osteoarthritis (LCKOA), and to provide a basis for the treatment of LCKOA.

METHODS

From January 2021 to January 2024, analyzed retrospectively clinical data of 74 patients with LCKOA treated with LUKA, TKA and LCCK arthroplasty. According to the operation plan, the patients were divided into three groups: LUKA group (23 cases), TKA group (23 cases) and LCCK group (28 cases). The changes of hip-knee-ankle (HKA) angle of the affected knee before and after operation were measured. All patients were assessed using the operation time, blood loss during operation, incision length, visual analogue scale (VAS) score before operation and after operation, Hospital for Special Surgery score (HSS), Oxford Knee Score (OKS), range of motion (ROM).

RESULTS

All 74 patients were followed up for (2.38 ± 0.33) years. The operation time, blood loss during operation, incision length and VAS score after operation in the LUKA group were significantly less than those in the TKA group and LCCK group (P < 0.05); HKA valgus angle, ROM, HSS score and OKS score of the three groups after operation were significantly better than those before operation (P < 0.05); There was no significant difference among the three groups in HSS score and OKS score (P > 0.05).

CONCLUSION

LUKA, TKA and LCCK arthroplasty have good clinical effect in the treatment of LCKOA; Compared with TKA and LCCK arthroplasty, LUKA has the advantages of less trauma, less bleeding, less pain and quick recovery. The short-term effect is satisfactory, and the long-term effect remains to be observed.

Fractures around the knee in elderly patients: Balancing fixation and arthroplasty approaches, a multicenter experience.. Injury 2024;55 Suppl 4:111347. [PMID: 39542571 DOI: 10.1016/j.injury.2024.111347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

INTRODUCTION

In recent years, a discernible shift has occurred in the approach to knee pathologies, specifically in the management of acute fractures. Traditionally, fractures were primarily treated through osteosynthesis, whereas prosthesis replacement was primarily reserved for degenerative issues. Outcomes of this investigation aim to elucidate the potential indications and contraindications for the use of prosthetic interventions in the management of such fractures and to propose a scoring system that can be adopted for the choice between the two different approaches.

METHODS

A retrospective observational study was conducted on patients treated for periarticular knee fractures, with a focus on elderly patients. Patients aged older than 65 years treated in three Italian centers were recruited. Inclusion criteria comprised fractures around the knee, including distal femur types 33-A, 33-B, and 33-C, and proximal tibia types 41-A, 41-B, and 41-C, in accordance with the AO/OTA classification. Surgical treatment with osteosynthesis or arthroplasty was required and investigated.

RESULTS

Between August 2017 and October 2022, 91 patients with periarticular knee fractures underwent surgical treatment, 23.1 % males and 76.9 % females, with 78 % undergoing osteosynthesis and 22 % acute total knee replacement. Distal femoral fractures constituted 37.4 %, while 62.6 % were proximal tibial fractures. Average age at surgery was 76.4 years. Patient outcomes were assessed using PROMs, revealing generally positive results, including survivorship of 95 % at the final follow-up for both groups using the Kaplan Meier survival estimate. The study introduces a novel Total Knee Replacement Indication Scoring System (TKRISS) based on the AO Classification.

CONCLUSIONS

Nowadays osteosynthesis remains the main treatment for fractures around the knee. In a geriatric patient's population and in carefully selected patients replacement can be a valid option for early weight bearing and quicker recovery comparing to fixation. The Total Knee Replacement Indication Scoring System provides a useful tool for healthcare to assess the potential indication for TKR in the context of knee fractures. It integrates a range of relevant factors, acknowledging the complex nature of patient care. Further clinical research and validation are essential to refine and optimize this scoring system.

The use of a modern robotic system for the treatment of severe knee deformities

BACKGROUND

Robotic-assisted total knee arthroplasty (TKA) have shown promising results in recent years with improved clinical outcomes using standard primary implants.

OBJECTIVE

The purpose of this study was to assess the experience of a single center in correcting severe coronal deformities with the use of a robotic-assisted TKA system and an increased constrained implant.

METHODS

Between July 2020 and December 2022, 30 knees in 28 patients with a major deformity and an associated ligament laxity requiring an increased constrained implant treated using an imageless robotic-assisted TKA were prospectively enrolled. Patients included in the study showed a minimum 15 degrees varus or 10 degrees valgus deviation.

RESULTS

20 cases were varus knees and 10 cases were valgus knees. Postoperative neutral alignment was defined as 0∘± 2.5∘. A CCK implant was used in 20 cases while a Constrained Posterior Stabilized implant was used in 10 cases. A neutral alignment was achieved in all patients. At a minimum 6 months follow up (f-u 6-30 months) clinical outcomes including ROM, KSS, HSS, OKS and WOMAC showed significant improvement and no major complications were registered.

CONCLUSIONS

The robotic system showed the achievement of a mechanical alignment with reliable radiographic outcomes and clinical results in the treatment of major deformities of the lower limb with the use of higher constrained implants at short term follow up. Further follow up and studies are necessary to confirm and verify these promising outcomes.