The Cost of Stiffness After Total Knee Arthroplasty

BackgroundStiffness after primary total knee arthroplasty (TKA) is debilitating and poorly understood. A heterogenous approach to the treatment is often utilized, including both nonoperative and operative treatment modalities. The purpose of this study was to examine the prevalence of treatments used between stiff and non-stiff TKA groups and their financial impact.MethodsAn observational cohort study was conducted using a large database. A total of 12,942 patients who underwent unilateral primary TKA from January 1, 2017, to December 31, 2017, were included. Stiffness after TKA was defined as manipulation under anesthesia and a diagnosis code of stiffness or ankylosis, and subsequent diagnosis and procedure codes were used to identify the prevalence and financial impact of multiple common treatment options.ResultsThe prevalence of stiffness after TKA was 6.1%. Stiff patients were more likely to undergo physical therapy, medication, bracing, alternative treatment, clinic visits, and reoperation. Revision surgery was the most common reoperation in the stiff TKA group (7.6%). The incidence of both arthroscopy and revision surgery were higher in the stiff TKA population. Dual component revisions were costlier for patients who had stiff TKAs ($65,771 versus $48,287; P < .05). On average, patients who had stiffness after TKA endured costs from 1.5 to 7.5 times higher than the cost of their non-stiff counterparts during the 2 years following index TKA.ConclusionPatients who have stiffness after primary TKA face significantly higher treatment costs for both operative and nonoperative treatments than patients who do not have stiffness.     

Causes of Instability After Total Knee Arthroplasty

The purpose of the present study was to characterize the underlying causes that lead to instability after total knee arthroplasty (TKA). We reviewed 83 revision TKAs (79 patients) performed for instability. After detailed analysis of patient's history, physical examination, operative report and radiographs, we identified six categories: flexion/extension gap mismatch, component malposition, isolated ligament insufficiency, extensor mechanism insufficiency, component loosening, and global instability. Twenty-five knees presented with multi-factorial instability. When these knees were classified according to the most fundamental category, each category above included 24, 12, 11, 10, 10 and 16 knees respectively. The unstable TKA may result from a variety of distinct etiologies which must be identified and treated at the time of revision. The revision TKA could be tailored to the specific causes.     

Stiffness After Revision Total Knee Arthroplasty

Stiffness after a revision total knee arthroplasty (TKA) is a disabling complication that has largely been overlooked in the literature. This study attempts to define the prevalence of stiffness after revision TKA and to determine the risk factors that may lead to its development. Thirty-two knees (4.0%) presented with stiffness that we defined as a range of motion less than 90°. Risk factors were found to be poor preoperative range of motion, stiffness as primary indication for revision, younger age, shorter interval between index primary and revision TKA, presence of well-fixed components at the time of revision, postoperative wound drainage, and lower Charlson index. Because of the challenges of treating stiffness, efforts should be invested in preventing this complication.     

No Major Functional Benefit After Bicompartmental Knee Arthroplasty Compared to Total Knee Arthroplasty at 5-Year Follow-Up

BackgroundIn case of isolated medial and patellofemoral joint arthritis, bicompartmental knee arthroplasty (BCA) is an alternative to total knee arthroplasty (TKA). The purpose of our prospective, randomized study is to compare the clinical outcome of BCA vs TKA.MethodsEighty patients with isolated medial and patellofemoral osteoarthritis were randomly assigned to either BCA or TKA. Patients were evaluated preoperatively, 3, 6, and 12 months, and 2 and 5 years after the procedure. Knee Society Score, Oxford Knee Score, and the University of California,Los Angeles activity scores were calculated at each follow-up; Forgotten Joint Score was assessed at final follow-up.ResultsThere was an improvement in Knee Society Score, Oxford Knee Score, and the University of California,Los Angeles scores in both groups but no significant differences between both groups at any follow-up. The Forgotten Joint Score at 5-year follow-up was not significantly different either. Range of motion was significantly greater in the BCA group from 1-year follow-up onward.ConclusionOur study did not show significant differences in clinical scores between BCA and TKA; only range of motion was significantly greater in BCA. Therefore, it is questionable whether this difference justifies the complexity of BCA associated with higher risk of failure. Maybe staged patellofemoral joint arthroplasty in the presence of a well-functioning UKA is an option for BCA and an alternative to revision to TKA. Long-term studies are needed to explore the potential benefits of BCA.     

Outcomes of a First Total Knee Arthroplasty Are Associated With Outcomes of the Subsequent Contralateral Total Knee Arthroplasty

BackgroundTo determine if preoperative characteristics and postoperative outcomes of a first total knee arthroplasty (TKA) were predictive of characteristics and outcomes of the subsequent contralateral TKA in the same patient.MethodsRetrospective administrative claims data from (SPARCS) database were analyzed for patients who underwent sequential TKAs from September 2015 to September 2017 (n = 5,331). Hierarchical multivariable Poisson regression (length of stay [LOS]) and multivariable logistic regression (all other outcomes), controlling for sex, age, and Elixhauser comorbidity scores were performed.ResultsThe cohort comprised 65% women, with an average age of 66 years and an average duration of 7.3 months between surgeries (SD: 4.7 months). LOS was significantly shorter for the second TKA (2.6 days) than for the first TKA (2.8 days; P < .001). Patients discharged to a facility after their first TKA had a probability of 76% of discharge to facility after the second TKA and were significantly more likely to be discharged to a facility compared with those discharged home after the first TKA (odds ratio [OR]: 63.7; 95% confidence interval [CI]: 52.1-77.8). The probability of a readmission at 30 and 90 days for the second TKA if the patient was readmitted for the first TKA was 1.0% (OR: 3.70; 95% CI: 0.98-14.0) and 6.4% (OR: 9; 95% CI: 5.1-16.0), respectively. Patients with complications after their first TKA had a 27% probability of a complication after the second TKA compared with a 1.6% probability if there was no complication during the first TKA (OR: 14.6; 95% CI: 7.8.1-27.2).ConclusionThe LOS, discharge disposition, 90-day readmission rate, and complication rate for a second contralateral TKA are strongly associated with the patient’s first TKA experience. The second surgery was found to be associated with an overall shorter LOS, fewer readmissions, and higher likelihood of home discharge.Level of EvidenceLevel 3-retrospective cohort study.     

Prior Knee Arthroscopy Is Associated With Increased Risk of Revision After Total Knee Arthroplasty

BackgroundKnee arthroscopy (KA) is frequently performed to provide improved joint function and pain relief. However, outcomes following total knee arthroplasty (TKA) after prior KA are not fully understood. The purpose of this study is to determine the relationship between prior KA within 2 years of TKA on revision rates after TKA.MethodsData were collected from the Humana insurance database using the PearlDiver Patient Records Database from 2006 to 2017. Subjects were identified using Current Procedural Terminology and International Classification of Diseases procedure codes to identify primary TKA. Patients were stratified into 2 groups based upon a history of prior KA. Univariate and multivariate analyses were conducted to determine association between KA and outcomes at 2-year postoperative period.ResultsIn total, 138,019 patients were included in this study, with 3357 (2.4%) patients receiving a KA before TKA and 134,662 (97.6%) patients who did not. The most common reason for KA was osteoarthritis (40.0%), followed by medial tear of the meniscus (26.0%) and chondromalacia (21%.0). After adjustment, prior KA was associated with increased revision rate (odds ratio [OR], 1.392; P = .003), postoperative stiffness (OR, 1.251; P = .012), periprosthetic joint infection (OR, 1.326; P < .001), and aseptic loosening (OR, 1.401; P = .048).ConclusionPrior KA is significantly associated with increased 2-year TKA revision rate. The most common etiology for arthroscopy was osteoarthritis. The results of the study, showing that arthroscopy before TKA substantially increases the rates of revision, PJI, aseptic loosening, and stiffness, lend further credence to the idea that patients may be better served by nonsurgical management of their degenerative pathology until they become candidates for TKA. Subjecting this population to arthroscopy appears to offer limited benefit at the cost of poorer outcomes when they require arthroplasty in the future.Level of EvidenceLevel III therapeutic study.     

Trends in Same-Day Bilateral Total Knee Arthroplasty

Between 2000 and 2009 demographics, comorbidity, complications, and 30-day mortality following same-day BTKA (SBTKA) in two high-volume institutions were obtained. Two 5-year periods were created to facilitate trend analysis. The percentage of SBTKA decreased by 36.2% in the latter period. A decline in mean age reflected mainly by a 50% decrease in patients > 75 years was observed. The average LOS decreased (5.7 vs. 4.5 days). Overall, selected patients were healthier in the second period. The prevalence of CAD and obesity decreased, whereas hypercholesteremia increased. The overall complication rate decreased by 55.5%; reduction in cardiac adverse events and acute posthemorrhagic anemia was observed. The rate of PE and 30-day mortality was unchanged with time. A need for more selective preoperative screening for potential candidates of SBTKAs is indicated.     

Improvements in Sexual Activity After Total Knee Arthroplasty

Background

Sexual limitations in the setting of total knee arthroplasty (TKA) are poorly understood.

Distal Femoral Arthroplasty for the Treatment of Periprosthetic Fractures After Total Knee Arthroplasty

Periprosthetic fractures after total knee arthroplasty present substantial challenge if associated with poor bone stock, fracture comminution, and loose or damaged components. Revision total knee arthroplasty with distal femoral arthroplasty is often necessary in these injuries. We reviewed 20 patients (22 knees) with a mean age of 69.5 years who underwent revision with distal femoral arthroplasty fracture. Patients were followed for an average of 58.6 months. At the latest follow-up, the mean Knee Society knee and functional score were 82.8 and 40, and the Short Form 36 mean physical functioning and mental functioning scores were 55.8 and 65.6, respectively. There were 10 postoperative complications with 5 patients requiring additional surgery. Distal femoral arthroplasty seems to be a viable option for complex periprosthetic femoral fractures after total knee arthroplasty. However, considering the relatively high rate of complications, this procedure should be reserved for patients where alternative treatments are not possible.     

Functional Disabilities and Satisfaction After Total Knee Arthroplasty in Female Asian Patients

This study was conducted to investigate functional disabilities and patient satisfaction in Korean patients after total knee arthroplasty (TKA). Of 372 female patients who had undergone TKA with a follow-up longer than 12 months, 261 patients (70.2%) completed a questionnaire designed to evaluate functional disabilities, perceived importance, and patient satisfaction. The top 5 severe functional disabilities were difficulties in kneeling, squatting, sitting with legs crossed, sexual activity, and recreational activities. The top 5 in order of perceived importance were difficulties in walking, using a bathtub, working, recreation activities, and climbing stairs. Severities of functional disabilities were not found to be correlated with perceived importance. The 23 patients (8.8%) dissatisfied with their replaced knees had more severe functional disabilities than the patients satisfied for most activities. The dissatisfied patients tended to perceive functional disabilities in high-flexion activities to be more important than the satisfied.     

Reconstruction of Disrupted Extensor Mechanism After Total Knee Arthroplasty

Background

Disruption of the extensor mechanism after total knee arthroplasty (TKA) is a debilitating complication that results in extension lag, limited range of motion, difficulty in walking, frequent falls, and chronic pain. This study presents the clinical and radiographic results of reconstruction after extensor mechanism disruption in TKA patients.

Chronic Thrombocytopenia and In-Hospital Outcomes After Primary Total Hip and Knee Arthroplasty

BackgroundThere is a lack of data on the influence of chronic thrombocytopenia (cTCP) on clinical outcomes following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). Limited studies mainly focused on postoperative heparin-induced TCP from single centers with small sample sizes. This study aims to describe the characteristics, trend, and outcomes of cTCP in patients undergoing THA and TKA from a nationally reprehensive perspective.MethodsWe identified THA and TKA patients with and without cTCP from the 2005 to 2015 Nationwide Inpatient Sample. Annual percent changes were calculated to reflect cTCP trends. Multivariable regression and propensity score analyses were conducted to investigate the association of cTCP and mortality, preoperative complications, cost as well as length of stay.ResultsIn total, 578,278 and 1,237,331 patients underwent primary THA and TKA, respectively. Proportion of cTCP annually increased by 6.95% in THA and 6.66% in TKA. Patients with cTCP were associated with higher risk of medical (odds ratio [OR] 2.00, 95% confidence interval [CI] 1.89-2.11) and surgical complications (OR 2.72, 95% CI 2.55-2.90) in THA, and higher risk of mortality (OR 1.68, 95% CI 1.22-2.31), medical (OR 1.94, 95% CI 1.85-2.03) and surgical complications (OR 2.55, 95% CI 2.38-2.73) in TKA. Additionally, higher cost and longer length of stay were observed in patients with cTCP for both surgical procedures.ConclusionPatients with cTCP had higher risk of mortality for TKA, more perioperative complications for both TKA and THA. Further studies are warranted to improve the preoperative management and to prevent worse outcomes associated with cTCP.     

Long-Term Mortality Trends After Revision Total Knee Arthroplasty

Background

Long-term mortality following primary total knee arthroplasty (TKA) is lower than the general population. However, it is unknown whether this is true in the setting of revision TKA. We examined long-term mortality trends following revision TKA.

Knee Arthroscopy After Total Knee Arthroplasty: Not a Benign Procedure

BackgroundOutcomes of knee arthroscopy (KA) after total knee arthroplasty (TKA) have been limited to small case series with short-term follow-up. The purpose of this study is to report the outcomes of patients who undergo a KA after a TKA using a large longitudinal database.MethodsThe PearlDiver Medicare database was queried for patients who underwent a KA procedure after a TKA on the ipsilateral extremity. A randomly selected control group was created by matching controls to cases in a 3:1 ratio based on age, gender, year of procedure, and Elixhauser Comorbidity Index. Revision for infection and all-cause revision were used as end points.ResultsA total of192 TKA patients who underwent a subsequent KA (TKA + KA group) were compared to 571 TKA patients who did not have a subsequent KA (TKA − KA group). The incidence of revision for infection was 6.3% in the TKA + KA group compared to 2.2% in the TKA − KA group (odds ratio, 2.87; P = .009). The incidence of all-cause revision was 18.8% in the TKA + KA group compared to 5.1% in the TKA − KA group (odds ratio, 4.34; P < .001).ConclusionKA after TKA was associated with increased infection-related and all-cause revision. The association between KA and subsequent infection requires further investigation.     

Migration of Polyethylene Fixation Screw After Total Knee Arthroplasty

Duracon (Howmedica, Rutherford, NJ) posterior stabilized total knee system has a snap fit locking mechanism of a tibial polyethylene, including an additional locking screw for further fixation of polyethylene. We report 13 cases of locking screw migration from tibial component after Duracon posterior stabilized primary total knee arthroplasty. Among 13 knees, screw migration in 10 asymptomatic cases was incidentally detected during regular follow-up, and they were just observed in the outpatient clinic. Only 3 knees had moderate pain, swelling, and instability, and revision was done on 2 of 3 knees.     

Biceps Tendinitis as a Cause of Acute Painful Knee After Total Knee Arthroplasty

The case report highlights an unusual case of posterolateral knee pain after total knee arthroplasty. Tendinitis of the patellar tendon or pes anserinus is a common complication after total knee arthroplasty; however, there is no report in the literature regarding the biceps femoris tendinitis causing acute pain in the early postoperative period. In this case, the biceps tendinitis was diagnosed and treated by ultrasound-guided injection into the tendon sheath.