Unicompartmental Knee Replacement Combined to Anterior Cruciate Ligament Reconstruction: Midterm Results

Medial Unicompartmental Knee Arthroplasty Combined With Anterior Cruciate Ligament Reconstruction Yields Similar Outcomes Compared to Unicompartmental Knee Arthroplasty Alone

Background: The treatment of unicompartmental knee osteoarthritis (OA) in young, active individuals with anterior cruciate ligament (ACL) insufficiency is a debatable topic. The objective, radiological, and functional results of medial unicompartmental knee arthroplasty (UKA) combined to ACL reconstruction and those of isolated UKA are compared in the present study. Methods: Twelve patients with medial OA and ACL incompetence were suitable for combined UKA and ACL reconstruction (Group A). A control group consisted of 24 patients who underwent isolated UKA within the same time frame and were matched for age, body mass index, and male/female ratio (Group B). The Oxford Knee Score (OKS), the Knee OA Outcome Score (KOOS), the WOMAC index of OA, and standard X-rays were used for clinical and radiologic evaluation. Results: The mean KOOS score, OKS, and WOMAC index improved 10 years after surgery, demonstrating a statistically significant change (p < 0.001). At follow-up, there was no significant between-groups difference concerning KOOS, OKS, or WOMAC scores (p=n.s.). One female patient in Group A underwent revision total knee arthroplasty (TKA) 3 years after the first surgery because OA in the lateral compartment had developed and the patient's discomfort persisted. There were no signs of pathologic radiolucent lines or radiographic signs of implant loosening at the most recent follow-up, which occurred at an average of 7.9 years for Group A and 9.1 years for Group B. Conclusion: Ten years after surgery, UKA combined to ACL reconstruction provides clinical and radiographic results similar to UKA without increasing the incidence of complications.

Novel application of an imageless robotic system in simultaneous unicompartmental knee arthroplasty and anterior cruciate ligament reconstruction

This technical note explores the novel use of an imageless robotic surgical system for simultaneous unicompartmental knee arthroplasty (UKA) and anterior cruciate ligament reconstruction (ACLR). Knee osteoarthritis (OA) and anterior cruciate ligament (ACL) insufficiency are common conditions that traditionally require separate management. The integration of robotic assistance offers enhanced precision in surgical procedures, addressing both medial compartment OA and ACL insufficiency in a single operation. We present a case involving a 47-year-old patient with medial compartment osteoarthritis and complete ACL rupture. The patient underwent a simultaneous robotic-assisted UKA and ACLR using the CORI Surgical System (Smith&Nephew, London, UK). This approach enables accurate tibial tunnel placement and precise soft tissue balancing. The robotic system facilitates real-time gap assessment and balancing, reducing the risk of over- or under-constraint during ACL graft tensioning. The procedure was performed with a standard medial parapatellar approach. Key steps included hamstring autograft harvesting, femoral and tibial tunnel creation, and robotic-assisted implant positioning. Post-operative rehabilitation allowed full weight-bearing by the third week. This case represents the first reported instance of using an imageless robotic system for simultaneous UKA and ACLR, highlighting its potential to standardize and improve results in complex knee surgeries. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Management of Medial Femorotibial Knee Osteoarthritis in Conjunction with Anterior Cruciate Ligament Deficiency: Technical Note and Literature Review

In recent years, there has been increased interest in the management of medial femorotibial knee osteoarthritis (OA) in conjunction with anterior cruciate ligament (ACL) deficiency. Traditional treatment modalities included conservative therapy, high tibial osteotomy with or without ACL reconstruction, and total knee replacement. Since younger patients with higher physical demands are more likely to suffer from this pathological condition, reduced invasiveness, faster recovery time, and improved knee kinematics are preferred to allow for satisfying clinical and functional outcomes. Thus, a new surgical strategy combining medial unicompartmental knee replacement (UKR) and ACL reconstruction has been proposed to allow bone stock preservation, to reduce surgical morbidity and recovery time, and ultimately to improve joint kinematics and clinical outcomes. Based on the data present in the literature, in the setting of unicompartmental OA in association with ACL deficiency, UKR combined with ACL reconstruction provided encouraging early results. Studies evaluating the outcomes of combined ACL reconstruction and UKR demonstrate promising results in select patient populations. Improved knee stability, pain relief, functional recovery, and patient satisfaction improved after surgery. Moreover, the combined approach offered advantages such as reduced surgical trauma, faster rehabilitation, and preservation of native knee anatomy compared with traditional treatment strategies. However, still, high-level studies on this topic are lacking; therefore, more comparative studies reporting long-term outcomes are needed to support the potential of this combined procedure to become mainstream. In this paper, we discuss the relevant features and rationale behind the indications and technique of this combined surgical procedure, to help surgeons choose the correct therapeutic approach for a patient with concomitant medial OA and ACL insufficiency. Continued advancements in surgical techniques, patient selection criteria, and rehabilitation strategies will further enhance the success of this combined approach, offering hope to individuals with concomitant ACL injuries and unicompartmental knee OA.

Unicompartmental knee arthroplasty combined with posterior cruciate ligament reconstruction: a case report

BACKGROUND

In this study, we present the unique case of a patient with knee osteoarthritis (OA) of the medial compartment and posterior cruciate ligament (PCL) deficiency who underwent simultaneous medial unicompartmental knee arthroplasty (UKA) and PCL reconstruction.

CASE PRESENTATION

A 49-year-old male patient presented with a 1-year history of pain and instability in the left knee. The patient had previously experienced a trauma-related injury to the PCL of the left knee that was left untreated. Imaging and physical examination confirmed the presence of left medial knee OA along with PCL rupture. To address these issues, the patient underwent UKA combined with PCL reconstruction. The patient's Lysholm score was 47 before surgery and 81 three months after surgery, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was 29 before surgery and 18 three months after surgery, and the International Knee Documentation Committee (IKDC) subjective score was 56.3 before surgery and 74.7 three months after surgery. Six months after surgery, the patient's gait returned to normal, and he was able to jog.

CONCLUSION

This case report presents the first instance of UKA combined with PCL reconstruction and introduces a novel treatment approach for patients suffering from medial knee OA and ligament injury.

Unicompartmental knee replacement combined with anterior cruciate ligament reconstruction provides comparable results to total knee replacement with no increased risk of complications

INTRODUCTION

There is controversy about the management of unicompartmental knee osteoarthritis (OA) in young, active patients with anterior cruciate ligament (ACL) insufficiency. This study compares the subjective, radiological, and functional results of total knee replacement (TKR) vs. combined medial unicompartmental knee replacement (UKR) with ACL reconstruction.

METHOD

Twelve patients suffering from medial OA and ACL deficiency with varus knee deformity and/or tibial slope <10° and absence of patellofemoral-related problems were eligible for combined UKR and ACL reconstruction (Group A). Twenty-six patients matched for age, male/female ratio and body mass index who received TKR in the same time frame were included as a control group (Group B). Oxford Knee Score (OKS), WOMAC index of osteoarthritis, Knee Osteoarthritis Outcome Score (KOOS), and routine X-rays were used for assessment.

RESULTS

Ten years after surgery, the mean overall KOOS score, OKS, WOMAC index increased from preoperatively, showing a statistically significant difference (p < 0.001). In terms of KOOS, OKS, or WOMAC scores at the most recent follow-up, there was no discernible difference between the groups (p = n.s.). Three years following surgery, one female patient in group A received revision TKR due to the lateral compartment's osteoarthritis developing and the patient's pain persisting. Concerning radiographic assessment, at the most recent follow-up (average 7.9 years in group A and 8.8 years in group B), there were no radiographic indications of implant loosening or proof of pathologic radiolucent lines.

CONCLUSIONS

UKR combined with ACL restoration offers clinical and radiographic outcomes comparable to TKR 10 years following surgery with no elevated risk of complications.

The Impact of Arthroscopy on Surgical Decision-Making and Outcomes in Osteoarthritis Patients Undergoing Unicompartmental Knee Arthroplasty

Background and objective Although unicompartmental knee arthroplasty (UKA) is a minimally invasive procedure, its application is limited due to strict criteria related to indications. In clinical practice, the aid of procedures such as arthroscopy is occasionally required to determine the surgical indication and thereby improve prognosis. In light of this, this study aimed to evaluate the impact of intraoperative arthroscopy on surgical decision-making in osteoarthritis (OA) patients and the prognosis of patients undergoing UKA. Methodology The clinical records of patients diagnosed with knee OA who underwent knee arthroplasty between January 2017 and January 2020 were retrospectively analyzed. The inclusion criteria were as follows: patients with radiographic evidence of single-compartmental Kellgren-Lawrence (KL) grade 3 or 4 knee OA but presenting symptoms of persistent multicompartmental knee pain or locking for at least six months, with a history of anterior cruciate ligament (ACL) injury or meniscus tear. They had undergone either UKA or total knee arthroplasty (TKA). Data on clinical characteristics and outcomes at baseline and during follow-up were collected. Results A total of 429 patients were included in the study. Patients who underwent arthroscopy were more likely to undergo UKA surgery than those who did not (p<0.05). Among patients who underwent UKA, no instances of blood transfusion during hospitalization or postoperative complications were reported, regardless of whether arthroscopy was performed or not. Although the overall Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores and Knee Society Functional Score (KSFS) did not differ between the two groups, the Knee Society Score (KSS) was significantly higher in patients who underwent arthroscopy (88.77 ±5.09) compared to those who did not (85.53 ±5.11). Similarly, the arthroscopy group had a higher overall Forgotten Joint Score (FJS) (44.6 ±4.20) than the UKA-only group (42.05 ±3.58). Conclusion Arthroscopy findings can assist in surgical decision-making for OA patients. Performing arthroscopy and UKA simultaneously is relatively safe and may be associated with favorable outcomes.

Unicompartmental knee arthroplasty: A French multicenteric retrospective descriptive study from 2009 to 2019 with projections to 2050

INTRODUCTION

Unicompartmental knee arthroplasty (UKA) is a reliable and reproducible procedure. While some surgeons have incorporated it into their therapeutic armamentarium, others do not use it routinely, leading to a large disparity in practice. The objective of this study was to investigate in France the epidemiology of UKA from 2009 to 2019 to identify: (1) the evolution of growth trends by sex and age, (2) the evolution of the state of comorbidity of patients during the operation, (3) the evolution of trends according to the regions, (4) the projection best suited to the observations at 2050.

HYPOTHESIS

Our hypothesis was that in France, an increase would be observed over the period studied, differing according to the characteristics of the population.

MATERIALS AND METHOD

The study was conducted in France over the 2009-2019 period for each gender and age group. The data was taken from the NHDS (National Health Data System) database, which includes all the procedures carried out in France. Based on the collection of procedures performed, the incidence rates (per 100,000 inhabitants) and their evolution were deduced, as well as the indirect assessment of the patient's comorbidity status. Using linear, Poisson, and logistic projection models, incidence rates were projected to the years 2030, 2040, and 2050.

RESULTS

Between 2009 and 2019, the incidence rate of UKA increased sharply (from 12.76 to 19.57; +53%), the growth was different in men (from 10.78 to 20.34; +89%) and women (from 14.61 to 18.85; +29%). The male/female sex ratio increased from 0.69 in 2009 to 1.0 in 2019. The increase was greatest among men under 65 (from 4.9 to 9.9; +100%) and lowest among women over 75 (from 41.2 to 40.5; -2%). Over the period studied, the proportion of patients with mild comorbidities (HPG1) increased (from 71.7% to 81.1%) at the expense of the other classes with more severe comorbidities. This dynamic was observed for all age groups: 0-64 years (from 83.3% to 90%), 65-74 years (from 81.4% to 88.4%), 75 years and over (38 .2% to 52.6%) regardless of sex. There was a strong disparity between the regions with a change in the incidence rate ranging from -22% (from 29.8 to 23.1) for Corsica to +251% (from 13.9 to 48.7) for Brittany. The proposed projection models suggested an increase in the incidence rate of +18% in logistic regression, +103% in linear regression by 2050.

DISCUSSION

Our study showed strong growth in the number of UKAs in France over the period studied, being highest in young men. The proportion of patients with fewer comorbidities increased for all age groups. A disparity in inter-regional practice was identified, with indications that remain ambiguous and differ according to the practitioner. We can expect continued growth in the years to come, adding to the care burden.

LEVEL OF EVIDENCE

IV; Descriptive epidemiological study.

Medial unicompartmental knee replacement is a viable treatment option after failed high tibial osteotomy: a systematic review

Purpose

Methods

Results

Conclusions

Unicompartmental vs. total knee replacement in patients with failed high tibial osteotomy

INTRODUCTION

The influence of a previous high tibial osteotomy (HTO) on the outcome and survival of a knee arthroplasty is a debated issue. The purpose of this study is to compare subjective, radiographic, and functional outcomes of unicompartmental knee replacement (UKR) and total knee replacement (TKR) after failed open wedge HTO.

METHODS

26 post-HTO UKRs (group A) with an average follow-up of 7.8 years (range 2-13), and 33 post-HTO TKRs (group B) with an average follow-up of 11.2 years (range 4-16) operated between 2001 and 2017, were retrospectively reviewed. Assessment included Knee Society Score (KSS), University of California at Los Angeles Activity Score (UCLA), and Western Ontario and McMaster University Osteoarthritis Index (WOMAC). Standard knee X-rays, and long-standing X-rays were performed pre-operatively and at follow-up to evaluate prosthesis survival, coronal alignment, and patellar height.

RESULTS

Improvements regarding KSS, UCLA and WOMAC scores were noted at follow-up in both groups compared to pre-operatory status (p < 0.001). No statistically significant differences in clinical and functional postoperative scores were reported between groups (p = n.s.) at follow-up. Group B presented a more neutral mean mechanical axis of 0.5° compared to 2.7° in Group A (p < 0.001).

CONCLUSIONS

Performing UKR after previous failed HTO is a safe and effective procedure which leads to clinical, radiological and functional outcomes comparable to TKR after HTO.

Hybrid Oxford unicompartmental knee arthroplasty has lower residual cement extrusion than cemented arthroplasty in treating end-stage unicompartmental knee osteoarthritis

Background

Hybrid Oxford unicompartmental knee arthroplasty (OUKA) consists of cementless femoral prostheses and cemented tibial prostheses. Although a hybrid OUKA has been used in clinical practice, the clinical outcome has not been reported. The purpose of this study was to compare the short-term clinical outcomes and rate of residual bone cement extrusion between hybrid and cemented prostheses and analyse the possible reasons for differences between outcomes.

Methods

A total of 128 knees (118 patients) with end-stage osteoarthritis were included in this study, of which underwent consecutive operations using unicondylar Oxford phase 3 implants from July 2017 and September 2019 in our centre. Follow-up was performed at 6 weeks, 3 and 6 months, 1 year and every year after operation, and complications and changes in the Oxford knee score (OKS) were recorded. The OKS of the two groups was analysed by the generalized estimating equation approach. Prosthesis-based standard fluoroscopy was performed in a timely manner after each operation, and the rate of residual cement extrusion of the two groups was estimated using T-tests and a multivariate regression analysis.

Results

Excluding the cases that lost follow-up, a total of 120 knees (65 in hybrid group and 55 in cemented group) were included in the analysis. There was no statistically significant difference in patient characteristics between the two groups (p > 0.05). The average follow-up time was 23.4 months (and ranged from 12 to 38 months). As of the last follow-up, there were no complications, such as dislocation, fracture, prosthesis loosening and subsidence, but one patient in the cemented group experienced symptoms caused by residual loose cement. Postoperative OKS in both groups improved significantly (p < 0.001). There was no significant difference in the OKS at any point during the follow-up or in the improvement of the OKS between the two groups (p > 0.05). Residual cement was mainly extruded behind the tibial prosthesis. The rate of hybrid periprosthetic residual cement extrusion was significantly lower in the hybrid group than in the cemented group, and the difference was statistically significant (OR = 3.38; p = 0.014).

Conclusions

Hybrid OUKA is as effective as cemented OUKA in the short term after operation and can significantly reduce the residual cement extrusion rate around the tibial prosthesis.

Results of Simultaneous Unicompartmental Knee Arthroplasty and Anterior Cruciate Ligament Reconstruction: A Systematic Review

This systematic review aimed to investigate the clinical and functional outcomes and complication rate of simultaneous anterior cruciate ligament reconstruction (ACLR) and unicompartmental knee arthroplasty (UKA). A systematic search in PubMed-Medline, Cochrane Library, and Google Scholar was carried out to identify eligible randomized clinical trials, observational studies, or case series that reported on clinical and functional results of combined ACLR and UKA in adults with a unicompartmental knee osteoarthritis and ACL deficiency. Four retrospective studies and three prospective studies were included in this review. A total of 169 patients were included with a mean follow-up of 6.3 years. The Mean Oxford Knee Score improved from 29.4 to 43.9 at the final follow-up. All the other reported scores significantly improved after surgery. The overall revision rate was 3.5%. The MINORS score ranged from 8 to 14. Association analysis of MINORS score and year of publication, through Pearson's coefficient, showed no significant association (p = -0.089). Simultaneous ACLR and UKA is a safe procedure with a significant postoperative improvement of functional and clinical outcomes for patients with ACL injury that complain of knee instability and isolated medial compartment pain.

Biomechanical effect of tibial slope on the stability of medial unicompartmental knee arthroplasty in posterior cruciate ligament-deficient knees

Aims

Unicompartmental knee arthroplasty (UKA) has become a popular method of treating knee localized osteoarthritis (OA). Additionally, the posterior cruciate ligament (PCL) is essential to maintaining the physiological kinematics and functions of the knee joint. Considering these factors, the purpose of this study was to investigate the biomechanical effects on PCL-deficient knees in medial UKA.

Methods

Computational simulations of five subject-specific models were performed for intact and PCL-deficient UKA with tibial slopes. Anteroposterior (AP) kinematics and contact stresses of the patellofemoral (PF) joint and the articular cartilage were evaluated under the deep-knee-bend condition.

Results

As compared to intact UKA, there was no significant difference in AP translation in PCL-deficient UKA with a low flexion angle, but AP translation significantly increased in the PCL-deficient UKA with high flexion angles. Additionally, the increased AP translation became decreased as the posterior tibial slope increased. The contact stress in the PF joint and the articular cartilage significantly increased in the PCL-deficient UKA, as compared to the intact UKA. Additionally, the increased posterior tibial slope resulted in a significant decrease in the contact stress on PF joint but significantly increased the contact stresses on the articular cartilage.

Conclusion

Our results showed that the posterior stability for low flexion activities in PCL-deficient UKA remained unaffected; however, the posterior stability for high flexion activities was affected. This indicates that a functional PCL is required to ensure normal stability in UKA. Additionally, posterior stability and PF joint may reduce the overall risk of progressive OA by increasing the posterior tibial slope. However, the excessive posterior tibial slope must be avoided.

Cite this article: Bone Joint Res 2020;9(9):593–600.