Conversion of a Surgically Arthrodesed Knee to a Total Knee Arthroplasty-Is it Worth it? A Meta-Analysis

Outcomes of Second-stage Reimplantation After Modular Knee Arthrodesis for Periprosthetic Joint Infection

Modular knee arthrodesis (MKU) is a salvage treatment for recurrent periprosthetic joint infection (PJI) or PJI associated with notable bone loss. Reimplantation endoprosthetic reconstruction (REI) is an option in patients with MKU who have PJI clearance but are not satisfied with pain or functional outcomes with MKU. The purpose of this study was to evaluate the outcomes of MKU to REI conversion.

A comparative study of total knee arthroplasty outcome for stiff knee with or without sequential antirheumatic drug treatment

BACKGROUND

The aim of this study was to evaluate the influence of antirheumatic drug treatment on knee function of stiff knee patients after total knee arthroplasty (TKA).

METHODS

Twenty-seven patients (44 knees) of active RA (rheumatoid arthritis) or AS (ankylosing spondylitis) with stiff knees were included in this study. And they were divided into two groups according to continue antirheumatic drug treatment or not after TKA: the therapeutic group (16 patients, 27 knees) and the controlled group (11 patients, 17 knees). The outcomes were assessed by Knee Society Score (KSS), Visual Analogue Scale (VAS), range of motion (ROM) (at week 6, month 6, year 1, and year 2), "Forgotten Joint" Scale (FJS), with or without crutch, satisfaction, and revision (at year 2). The knee prosthetic loosening was evaluated by the followed X-ray at each following time.

RESULTS

The mean follow-up time was 51 months (34-69 months). The KSS was higher at week 6 after TKA in the therapeutic group (p < 0.05); however, the functional scores of KSS at month 6, year 1, and year 2 in the controlled group were more points improved. The therapeutic patients preferred the knee more at month 6, year 1, and year 2. The differences of KSS clinical scores (at month 6, year 1, and year 2), VAS, ROM, Crutch and FJS between the two groups were not statistically significant (p > 0.05).

CONCLUSION

For patients with stiff knees, the sequential antirheumatic drug treatment after TKA had no obvious effect on postoperative KSS, but can improve the satisfaction.

LEVEL OF EVIDENCE

Therapeutic level II. See Instructions for Authors for a complete description of levels of evidence.

Classification-Based Management of Stiff/Ankylosed Knees

INTRODUCTION

Stiff knees are defined as those with an arc of motion < 50°. They pose a considerable surgical challenge to the operating surgeon. Based on our experience to deal with these complex cases, we have developed a working classification that outlines a flowchart to manage the stiff/ankylosed knees.

MATERIALS AND METHODS

It was a retrospective study conducted in our department. Out of 570 TKA performed in last 5 years, 57 had stiffness and four had bony ankyloses (total 61 knees). Patients were classified based on the fibrous or bony ankylosis and preoperative ROM.

RESULTS

Patients were followed for an average 2.4 years (1.8-5.5 years). KSS pain scores improved from an av. 32 preop (18-64) to av. 76 postoperatively (61-90). The KSS function scores improved from a preoperative value of 36 (16-56) to an av. 78 (52-90) postoperatively. ROM improved from an average of 35.6° (0°-44°) preoperatively to an average of 95.6° (ROM 73°-118°) postoperatively. Extension lag was an av. 8° (3°-12°) and was seen in 13 patients postoperatively. Residual fixed flexion deformity was an av. 7° (3°-14°) and seen in 17 patients. The stiff knees (type 1 and type 2) fared better than ankylosed knees (type 3) in all aspects. Complication rate was high (24%) in our series.

CONCLUSION

Our classification of stiff/ankylosed knees guides the surgeon to decide upon which approach to take, which implants to keep handy and has a predictive and prognostic value.

Conversion From Knee Arthrodesis Back to Arthroplasty: A Particular Challenge in Combination With Fungal Periprosthetic Joint Infection

A 58-year-old female treated at an outside facility with knee arthrodesis due to persistent periprosthetic joint infection fulfilled all prerequisites for a conversion back to arthroplasty, as part of a 2-stage revision. Owing to the detection of Candida parapsilosis, the treatment concept was converted to a three-stage procedure. A scheduled spacer exchange with additional amphotericin B-loaded polymethylmethacrylate was conducted as an intermediate revision before reimplantation. Conversion in the setting of fungal periprosthetic joint infection presents a challenge, and successful treatment hinges on the use of proper antifungal and antimicrobial protocols, advanced surgical techniques, and a multidisciplinary team approach. At the 3-year follow-up, successful infection eradication as measured by the Delphi-based consensus definition was achieved with a range of motion of 0°-100°.

Conversion Total Knee Arthroplasty: A Distinct Surgical Procedure With Increased Resource Utilization

BACKGROUND

Current Procedural Terminology coding currently makes no distinction between primary total knee arthroplasty (TKA) and conversion TKA, in which periarticular hardware components must be removed prior to or during TKA. We hypothesize that conversion TKA will carry increased operative time, blood loss, postoperative complications, and 90-day emergency department/readmission rate compared to primary TKA.

METHODS

Patients undergoing conversion TKA from 2005 to 2017 were identified from an institutional database and matched to primary TKA patients by age, gender, American Society of Anesthesiologists score, body mass index, and procedure date (±1 year). Intraoperative data and 90-day postoperative complications were compared between groups.

RESULTS

One hundred nine conversion TKA patients with periarticular hardware were removed prior to (n = 51) or during (n = 58) TKA and 109 primary TKA control patients were included. Conversion TKA was associated with increased tourniquet time (91 vs 71 minutes, P < .001), operative time (147 vs 113 minutes, P < .001), blood loss (225 vs 176 mL, P = .010), 90-day readmissions (14.6% vs 4.2%, P = .020), wound complication (5.6% vs 0.0%, P = .025), periprosthetic joint infection (7.9% vs 0.0%, P = .005), irrigation/debridement (9.0% vs 1.1%, P = .016), and a trend toward increased mechanical complication (6.7% vs 1.1%, P = .058). Timing of hardware removal did not affect intraoperative or postoperative outcomes.

CONCLUSION

Conversion TKA is associated with higher operative time, blood loss, readmission rate, and postoperative complications compared to primary TKA. Without a proper billing code and appropriate reimbursement level to match the expected operative and postacute resource utilization by these cases, physicians may be disincentivized to perform these operations.

What are the benefits and risks of total arthroplasty in arthrodesed knees?

INTRODUCTION

The conversion of a previously arthrodesed knee to a total knee arthroplasty is an alternative seldom used. However, arthroplasty would provide greater functionality to the arthrodesed joint. Since it is a technically demanding procedure, not exempt from complications, there is controversy about the role of this intervention.

METHODS

To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS

We identified two systematic reviews including 10 studies overall, none of which corresponded to a randomized trial. We concluded the conversion of knee arthrodesis to total knee arthroplasty could increase the functionality, but it is not clear whether it increases the complications or if it has any impact on pain or patient satisfaction because the certainty of the evidence is very low.

Knee arthrodesis: procedures and perspectives in the US from 1993 to 2011

BACKGROUND

The incidence and prevalence of knee arthrodesis (fusion) in the United States is largely unknown, in spite of numerous case reports and review articles that have called attention to this life altering procedure.

PURPOSE

This study was conducted to determine long-term knee arthrodesis incidence and patient populations, and to characterize the associated healthcare burden.

METHODS

The Nationwide Inpatient Sample was used to evaluate knee arthrodesis procedures performed in the United States between 1993 and 2011. Patient age, sex, and reimbursement method were evaluated along with hospital attributes. Procedural rates for individual demographics were calculated using population data from the US Census. Commonly occurring diagnoses and procedures in knee arthrodesis were compiled.

RESULTS

The annual number of reported knee arthrodesis procedures remained relatively unchanged between 1993 and 2011 (Mean 1014, Standard Deviation 113), but there was a small but significant decrease in the procedure rate when taking population changes into account. Over 80 % of patients were aged 45 or above. Approximately 65 % of patients utilized governmental payers for reimbursement. Nearly all of the procedures were performed in metropolitan area hospitals (92.5 %), and a significant majority performed in teaching hospitals (62 %).

CONCLUSIONS

The low incidence of knee arthrodesis procedures reflects both clinician and patient antipathy for this undesirable surgery. Case studies continue to reflect an interest to improve methodology, but also suggest a significant number of patients that go untreated given the current state of the art. Future work should seek to quantify the prevalence of patients with a severely dysfunctional knee who might otherwise undergo arthrodesis, but opt against it given the significant quality of life issues associated with the procedure.