Primary modular total knee replacement in severe and unstable osteoarthritis. Predictive factors for failure

Patient-Reported Outcomes and Range of Motion Following Knee Arthroplasty Using a Megaprosthesis in Non-Oncological Patients: A Systematic Review

BACKGROUND

This review aimed to determine outcomes following megaprostheses in non-oncological indications for knee arthroplasty, including range of motion (ROM) and patient-reported outcome measures of function, pain, and quality of life (QoL).

METHODS

A search of MEDLINE, Embase, and Cochrane via Ovid and PubMed between January 2003 and June 2023 was conducted. Studies reporting function, pain, ROM, and/or QoL in non-oncological patients who have received knee megaprostheses were included. Studies with sample sizes (n ≤ 5) were excluded. The risk of bias was assessed using the Downs and Black Quality Checklist for Health Care Intervention Studies. Central tendency measures (mean or median) were reported at each time point, and dispersion measures were extracted and reported whenever data were available.

RESULTS

A total of 30 studies (involving 1,294 megaprostheses) were included. Of which, 14 of 30 studies reviewed patients who had mixed indications; 14 of 30 looked at fracture only; 1 of 30 focused on distal femur nonunion; and 1 of 30 focused on patients who had periprosthetic infections. The average patient follow-up time was 40.1 months (range, 1.0 to 93.5). Most studies presented a high risk of bias (27 of 30), while a few (3 of 30) presented a low risk of bias. Improvements from preoperative baseline were observed in 85.7% of studies that reported baseline and follow-up data for function (12 of 14), 100.0% pain (4 of 4), 90.9% ROM (10 of 11), and 66.6% QoL (2 of 3).

CONCLUSIONS

Favorable function, pain, ROM, and QoL outcomes following knee megaprostheses in non-oncological patients were observed. Heterogeneity in outcome measures and follow-up periods prevented the pooling of data. Future comparative studies are warranted to enhance the body of evidence relating to knee megaprostheses in non-oncological patients.

Long-term results (after a mean 11.3years, and up to 22years, of follow-up) of the Legacy Constrained Condylar Knee (LCCK™) in primary total knee arthroplasty

INTRODUCTION

The use of a sliding prosthesis in total knee arthroplasty (TKA) with increased stress is an intermediate solution in primary surgery, between posteriorly stabilized prostheses and hinged prostheses, in cases of ligamentous laxity and/or loss of bone substance. Favorable results have been reported in the medium term but to our knowledge, this type of prosthesis has not been evaluated in Europe beyond 10 years of follow-up. We therefore conducted a retrospective study in order to carry out: 1) the study of the survival of the Legacy Constrained Condylar Knee (LCCK™) prosthesis in primary surgery, 2) the analysis of complications, functional scores and radiographic data, 3) the analysis of the link between the diaphyseal filling rate and prosthetic loosening.

HYPOTHESIS

The LCCK™ sliding prosthesis with increased constraint has equivalent long-term survival and clinical results to standard posteriorly stabilized TKA and superior to hinged TKA.

MATERIAL AND METHOD

A retrospective series of 141 LCCK™ implanted in 134 patients between 1997 and 2010 was analyzed. Survival was assessed with censoring through an evaluation of partial or total revision of the implants. The functional results were evaluated using the IKS and Oxford 12 scores. Data regarding the Canal Fill Ratio (CFR) and the presence of pathological periprosthetic lines were also collected.

RESULTS

The average follow-up was 11.3±5.3years with a maximum follow-up of 22.7years. Survival at 20years was 90.8% [95% CI: 83.7-95.7]. The rate of early complications was 13.5% (19/141), predominantly comprised of venous thrombosis (6/141), hematomas (3/141 including two requiring surgical drainage), stiffness (3/141) and early infections (3/141). The rate of late complications was 17% (24/141), led by stiffness (4.4%; 6/141), infections (2.9%; 4/141) and hardware failure (2. 2%; 3/141). Ten of the 141 patients (7.1%) had LCCK failure, including 3 (2.1%) for stiffness, 3 (2.1%) for hardware failure, 2 (1.4%) for infection, 1 (0.7%) for laxity and 1 (0.7%) for a periprosthetic fracture. No aseptic loosening was found. The total IKS score went from 65 [0-116] to 143 [79-200] at follow-up, the IKS knee score went from 30 [0-66] to 85 [44-100], and the IKS function score went from 35 [0-70] to 57 [0-100]. The Oxford score went from 14 [2-25] to 34 [15-48] at follow-up. Only two patients (1.4%) presented with a partial periprosthetic line. The tibial CFR was 0.81 and the femoral CFR was 0.76. The influence of the CFR could not be analyzed due to the absence of loosening.

DISCUSSION

The LCCK™ prosthesis in primary surgery has good medium-term survival, a significant improvement in functional scores and a complication rate comparable to posteriorly stabilized prostheses. The complication rate is lower than that of hinged prostheses.

LEVEL OF EVIDENCE

IV; single-center retrospective study.

Good to excellent long-term survival of a single-design condylar constrained knee arthroplasty for primary and revision surgery

PURPOSE

The purpose of the study was to determine the long-term survivorship, functional outcomes of a single-design condylar constrained (CCK) TKA in primary and revision cases as well as to assess specific risk factors for failure. It was hypothesized that primary CCK TKA had a better survival than revision knees.

METHODS

One hundred and forty three patients who underwent revision TKA (n = 119) or complex primary TKA (n = 24) using a single-design condylar constrained knee system (Genesis CCK, Smith & Nephew) performed at a single institution between 1999 and 2008 were retrospectively included. The median follow-up amounted to 11.8 years (IQR 10.3-14.4). Implant survivorship was analyzed using Kaplan-Meier survival estimates and multivariate Cox regression analysis to identify risk factors for failure. Function was determined using the Oxford Knee Score (OKS).

RESULTS

The implant survival was 86.4% after five, 85.5% after ten and 79.8% at 15 years. A reduced implant survivorship was found in males (HR 5.16, p = 0.001), smokers (HR 6.53, p = 0.004) and in obese patients (HR 2.26, p = 0.095). Patients who underwent primary TKA had a higher revision-free implant survivorship compared to revision TKA at 15 years (100% vs. 76%, p = 0.036). The main cause for re-revision was infection in 10% of all revision TKA performed with the CCK design included, while no case was revised for instability. The median OKS was 39 (IQR 35-44) in 102 patients available for long-term functional outcome.

CONCLUSION

CCK implants are associated with excellent long-term survival when used in primary TKA; however, survival was worse when used during revision TKA. Males, smokers, obese patients and are at higher risk for revision. While instability and aseptic loosening were rare, infection remains a major concern.

LEVEL OF EVIDENCE

Level IV, retrospective observational study.

A Comparison Between Unstemmed and Stemmed Constrained Condylar Knee Prostheses in Primary Total Knee Arthroplasty: A Propensity Score-Matched Analysis

Objective

To compare and analyze the clinical outcomes between unstemmed and stemmed constrained condylar knees (CCK) in complex primary total knee arthroplasty (TKA) in terms of implant survivorship, change in outcome evaluations, and complications.

Methods

We reviewed 156 consecutive patients who received primary TKA using PFC®SIGMA®TC3 (TC3) of constrained condylar design between January 2009 and January 2017 at our institution. After removing patients who met exclusion criteria, 25 patients were identified as unstemmed TC3 cases and 81 as stemmed TC3 cases. Propensity score matching was used to select 25 stemmed cases as a control group for the unstemmed group with comparable preoperative conditions including preoperative demographics, preoperative diagnosis, preoperative range of motion, main reason to use TC3, ASA score (American Society of Anesthesiologists), and follow‐up duration. Preoperative and postoperative clinical evaluations including Knee Society Score (KSS), Hospital for Special Surgery (HSS) score, the 12‐Item Short‐Form Health Survey (SF‐12), and the range of motion (ROM) were obtained and compared. The instability, periprosthetic fracture, radiolucent lines, polyethylene wear, and heterotrophic ossification were assessed according to the anteroposterior and lateral radiographs of the knee. The complications and implant survivorship between the two groups were also recorded and compared.

Results

3After the index surgery, both groups showed substantial improvement in KSS (knee and function), HSS score, SF‐12, and ROM compared with baseline. There was no significant difference in the mean KSS scores (knee and function), HSS score, SF‐12, and ROM between the unstemmed and stemmed group postoperatively. No statistically significant difference was found in the overall complication rate between the two groups. The overall Kaplan–Meier survivorship was 98.0% (95% confidence interval 94.1%–100.0%) at 7 years. No significant difference was found in the survival rate between the unstemmed group (100.0%) and the stemmed group (96.0%) at 7 years (log rank, P = 0.317). The mean duration of follow‐up was 7.0 years for unstemmed group and 7.7 years for stemmed group.

Conclusions

In patients with adequate bone stock receiving complex primary TKA, unstemmed CCK could achieve similar clinical outcomes at mid‐term follow‐up as stemmed CCK.

Is varus-valgus constraint a reliable option in complex primary total knee arthroplasty? A systematic review

Purpose

Knee instability is considered one of the most frequent cause of failure after primary total knee arthroplasty (TKA). In order to address intraoperative instability, varus-valgus constrained knee implants (VVC) are increasingly utilized in primary TKA. Despite an increased risk of mechanical failure, short to mid-term results seem to be encouraging, but long-term results are still lacking.

Methods

A systematic review of prospective and retrospective studies that reported clinical outcomes of patients with VVC systems in primary TKAs between 1990 and 2020 was performed.

Results

In all, 28 articles met our inclusion criteria. A total of 2798 VVC implants were used in primary TKA. The all-cause revision-free survivorship was 95.2% at a mean follow-up of 7 years. Infection and aseptic loosening were the most common reasons for reoperation with an incidence of 1.8% and 1.7%, respectively. Overall complication rate was 9.6%, the most common complications were knee stiffness and infection with an incidence of 2.8% and 2.5%, respectively.

Conclusions

VVC implants in primary TKA are associated with improved functional outcomes and good mid-term survivorship, comparable to lower level of constraint implants. Non-modular stemless seem to be reliable implants at mid-term follow-up. However, given the lack data coming from long-term studies, VVC implants should be used cautiously in primary TKA.

When to Use a Condylar Constrained Insert in Non-Stemmed Posterior-Stabilized Total Knee Arthroplasty

Backgroud

The constrained insert with non-stemmed tibial and femoral components can be used in the modern total knee arthroplasty (TKA) when soft-tissue balance and adequate stability from a posterior-stabilized (PS) insert cannot be achieved. This study aimed to identify the prevalence and predictive factors associated with the constrained insert use during primary TKA for varus deformity.

Methods

From August 2016 to March 2019, 554 primary TKAs were consecutively performed by one surgeon. The choice of using a conventional PS polyethylene insert versus a constrained insert was made by the surgeon, depending on the stability detected after an attempt to balance the soft tissue. The decision to convert to a constrained liner was made if the ligament could not be balanced, if flexion-extension gaps were mismatched, or if the varus-valgus opening was 3 mm or more when varus and valgus stress tests at 0° were applied. We retrospectively investigated the preoperative, intraoperative, and postoperative factors associated with the constrained insert use. Multiple logistic regression analysis was used to identify predictive factors of constrained insert use, and a receiver operating characteristic curve analysis was used to pinpoint a cutoff value of tibiofemoral varus angle.

Results

Constrained inserts were used in 130 of 497 varus knees (26.1%). A multivariate analysis revealed that the factors associated with an increased adjusted risk of constrained insert use included preoperative severe varus deformity (odds ratio [OR], 5.78; 95% confidence interval [CI], 2.75–12.16; p < 0.001) and severe release of soft tissue through the superficial medial collateral ligament (OR, 6.38; 95% CI, 2.94–13.85; p < 0.001). A preoperative anatomic tibiofemoral varus angle of > 19.8° was associated with the use of a constrained articulation with an area under the curve of 0.7 (95% CI, 0.4–0.8).

Conclusions

Prevalence of 26.1% for constrained insert use was found in this study. Preoperative anatomic tibiofemoral varus angle of > 19.8° and severe release of soft tissue through the superficial medial collateral ligament were associated with the use of a constrained articulation. The findings from this study will help surgeons to improve efficiency of surgical sequence planning and provide counseling to patients regarding the associated cost.

Satisfactory mid-term outcomes of condylar-constrained knee implants in primary total knee arthroplasty: clinical and radiological follow-up

Background

The purpose of this study was to evaluate (1) the reoperation rates and survivorship for septic and aseptic causes, (2) radiographic outcomes, and (3) clinical outcomes of condylar-constrained knee (CCK) implants used in primary total knee arthroplasty (TKA) with severe coronal deformity and/or intraoperative instability.

Materials and methods

A consecutive series of CCK implants in primary TKA was retrospectively evaluated in patients with severe coronal deformities. Forty-nine patients (54 knees) were included with a mean follow-up of 9 years (range 6–12). All patients were treated with a single-design, second-generation CCK implant. The primary diagnosis was osteoarthritis in 36 knees, post-traumatic arthritis in 7 knees, and rheumatoid arthritis in 4 knees. Preoperatively, standing femorotibial alignment was varus in 22 knees and valgus in 20 knees.

Results

At a mean follow-up of 9 years, overall survivorship was 93.6%. Two knees (4.3%) required revision for periprosthetic joint infection. One knee (2.1%) required subsequent arthroscopy due to patellar clunk syndrome. At final follow-up, no evidence of loosening or migration of any implant was reported, and the mean Knee Society knee scores improved from 43 to 86 points (p < 0.001). The mean Knee Society function scores improved to 59 points (p < 0.001). The average flexion contracture improved from 7° preoperatively to 2° postoperatively and the average flexion from 98° to 110°. No knees reported varus–valgus instability in flexion or extension.

Conclusion

CCK implants in primary TKA with major coronal deformities and/or intraoperative instability provide good midterm survivorship, comparable with less constrained implants. In specific cases, CCK implants can be considered a viable option with good clinical and radiographic outcomes. However, a higher degree of constraint should be used cautiously, leaving the first choice to less constrained implants.

Level of evidence Therapeutic study, level IV.

Abnormally high dislocation rate following constrained condylar knee arthroplasty for valgus knee: a case-control study

Background

With the use of constrained condylar knee (CCK) prostheses, dislocation of the knee following total knee arthroplasty (TKA) with valgus deformity is rare. In our practice with such patients, however, an abnormally high dislocation rate was noted. It appeared to be associated with the extent of soft-tissue release which varied among surgeons following different sequences of release. We asked in CCK TKA with valgus deformity is releasing both the lateral collateral ligament (LCL) and popliteus tendon (PT) associated with the occurrence of dislocation.

Methods

This is a case-control study of consecutive patients with valgus deformity who underwent primary CCK TKA between July 2008 and October 2015. The cases and controls were patients with and without postoperative dislocation of the knee, respectively. The extent of the release of lateral soft-tissue structures was compared between the two groups. Other patient characteristics including age, body mass index, pre- and post-operative valgus deformity, preoperative flexion-contracture, and height of the polyethylene insert were compared as well to reduce confounding.

Results

Forty-three consecutive patients with a minimum 2-year follow-up were enrolled. 9.3% (4/43) of the patients had postoperative dislocation of the knee. While the dislocated patients did not significantly differ from the controls on most characteristics, they were more likely to have both the LCL and PT released together during the surgery [100% (4/4) vs. 2.6% (1/39), P < 0.001].

Conclusion

Releasing both LCL and PT in CCK TKA with valgus deformity may increase the risk of dislocation, and need to be performed with some caution.

Outcomes after knee arthroplasty in extra-articular deformity

PURPOSE

To assess functional outcomes in patients undergoing total knee arthroplasty (TKA) without previous corrective osteotomy for treatment of knee osteoarthritis associated with extra-articular deformity.

METHODS

From January to December 2016, patients with knee osteoarthritis with extra-articular deformities who presented for preoperative assessment before TKA were evaluated prospectively. Physical and radiological characteristics were documented pre- and postoperatively.

RESULTS

TKA was performed in 33 knees; 25 were considered for analysis. The mean age was 65.2 years (range, 48-79 years). Sixteen deformities were secondary to fractures and nine to failed osteotomies. The mean Knee Society Score (KSS) improved from 27.1 pre-operatively to 68.7 post-operatively (p = 0.000). Pre-operative mechanical axis ranged from 32° varus (negative) to 26° valgus. After correction, 20 knees were within 3° (varus or valgus) of mechanical alignment.

CONCLUSION

In patients with extra-articular deformities, TKA with asymmetric intra-articular resection and ligament balancing can relieve pain and realign the mechanical axis of the lower limb.

[Effectiveness of condylar constrained knee prosthesis for destructive hemophilic arthritis]

Objective

To investigate the clinical outcomes of total knee arthroplasty (TKA) by using the condylar constrained knee prosthesis in the treatment of destructive hemophilic arthritis.

Methods

Between September 2007 and July 2015, 8 cases (8 knees) of destructive hemophilic arthritis accepted TKA by using condylar constrained knee prosthesis. All patients were male, aged 22 to 56 years, with an average age of 35 years. The disease course of hemophilia A was 3-30 years (mean, 17.3 years). Preoperative range of motion (ROM) was (68.1±32.6)°; the flexion deformity was (14.38±16.13)°. Six patients had valgus of 7-35° (mean, 17.3°), of whom, one had fixed dislocation of patella; and one had varus of 15°. Hospital for Special Surgery (HSS) knee score was 52.5±12.9. Pre-operative X-ray film examination demonstrated narrowing of the knee gap and cystic degeneration of articular cartilage and subchondral bone.

Results

All patients achieved primary wound healing, and were followed up 1-9 years (mean, 5 years). Tense blister with common peroneal nerve damage and extension penetrating into distal tibial cortex occurred in 1 case respectively, which were cured corresponding treatment. At last follow-up, the knee ROM and the flexion deformity were significantly improved to (98.1±8.9)° and (0.63±1.77)° ( t=-2.527, P=0.036; t=2.396, P=0.047). At 2 weeks after operation and last follow-up, the HSS scores were significantly increased to 77.3±11.0 and 85.0±9.0 ( P<0.05). X-ray film showed that lower extremity alignment returned to normal in patients with varus and valgus.

Conclusion

Good curative effect can be get by using condylar constrained knee prosthesis in TKA for the treatment of destructive hemophilic arthritis.