Outcomes of Total Knee Arthroplasty Revisions in Obese and Morbidly Obese Patient Populations

BackgroundThe obese population is at higher risk for complications following primary total knee arthroplasty (TKA), but little data is available regarding revision outcomes. This study aimed to investigate the role of body mass index (BMI) in the cause for revision TKA and whether BMI classification is predictive of outcomes.MethodsA multi-institutional database was generated, including revision TKAs from 2012 to 2019. Data collection included demographics, comorbidities, surgery types (primary revision, repeat revision), reasons for revision, lengths of hospital stay, and surgical times. Patients were compared using 3 BMI categories: nonobese (18.5 to 29.9), obese (30 to 39.9), and morbidly obese (≥40). Categorical and continuous variables were analyzed using chi-square and 1-way analysis of variance tests, respectively. Regression analyses were used to compare reasons for revision among weight classes.ResultsObese and morbidly obese patients showed significant risk for repeat revision surgery in comparison to normal weight patients. Obese patients were at higher risk for primary revision due to stiffness/fibrosis and repeat revision due to malposition. In comparison to the obese population, morbidly obese patients were more likely to require primary revision for dislocation and implant loosening.ConclusionSignificant differences in primary and repeat revision etiologies exist among weight classes. Furthermore, obese and morbidly obese patients have a greater risk of requiring repeat revision surgery. These patients should be informed of their risk for multiple operations, and surgeons should be aware of the differences in revision etiologies when anticipating complications following primary TKA.     

The Association of Metabolic Syndrome on Complications and Implant Survivorship in Primary Total Knee Arthroplasty in Morbidly Obese Patients

BackgroundMetabolic syndrome (MetS) includes interrelated conditions such as insulin resistance, abdominal obesity, hypertension, and dyslipidemia. This study sought to determine the association of MetS in morbidly obese patients (body mass index >40) on complications and clinical outcomes after primary total knee arthroplasty (TKA).MethodsA retrospective review was performed to include all morbidly obese patients who underwent primary elective TKA for osteoarthritis at a single academic institution. Patients who did and did not have MetS were propensity-matched 1:1 based on baseline characteristics. A total of 391 patients who did and 935 who did not have MetS were included having a mean body mass index of 44.2 (range, 40.0 to 68.9).ResultsThe MetS patients had longer lengths of stay (LOS) (3.5 ± 2.4 versus 3.0 ± 1.5 days, P = .001) and were more likely to be discharged to skilled nursing facilities (23.8 versus 15.3%, P = .007). At 90 days postoperatively, major (P = .756) and minor (P = .652) complication rates and readmissions (P = .359) were similar. Revision rates as well as improvements in KOOS-JR, and VR-12 mental and physical component scores from preoperative to 1 year (P = .856, P = .524, and P = .727, respectively) postoperatively did not significantly differ between groups. MetS and non-MetS patients had similar 5-year freedom from all-cause revision (90.2 versus 94.2%, P = .791).ConclusionMorbidly obese patients who have MetS had longer LOS and higher discharges to skilled nursing facilities. The 90-day complications, readmissions, revision rates, and patient-reported outcomes were similar, suggesting that resource allocation should be focused on perioperative protocols that can help optimize LOS and discharge dispositions in morbidly obese MetS patients undergoing TKA.Level of evidenceIII.     

Postoperative Complications of Total Joint Arthroplasty in Obese Patients Stratified by BMI

Background

High body mass index (BMI) is associated with significant complications in patients undergoing total joint arthroplasty. Many studies have evaluated this trend, but few have looked at the rates of complications based on BMI as a continuous variable. The purpose of this study was to stratify obese patients into 3 BMI categories and evaluate their rates of complications and gauge whether transitioning from higher to lower BMI category lowers complication.

Robotic-Assisted Laparoscopic Hysterectomy: Outcomes in Obese and Morbidly Obese Patients

Objective:

To describe patient characteristics and perioperative outcomes among women undergoing robotic-assisted laparoscopic hysterectomy and to evaluate the characteristics of nonobese, obese, and morbidly obese patients.

Methods:

A retrospective review was conducted of 442 cases of women who underwent robotic-assisted laparoscopic hysterectomy for benign and malignant conditions over a 4-y period at an academic and community teaching hospital. Patient demographics, surgical indications, operative outcomes, and complications were evaluated for patients with a body mass index (BMI) <30 kg/m², 30 kg/m² to 39.9 kg/m², and ≥40 kg/m².

Results:

Of the 442 patients, 257 (58%) were obese or morbidly obese, with a BMI of ≥30 kg/m². Overall, the median estimated blood loss was 100 mL (range, 10 to 800), the operative time was 135 min (range, 40 to 436), and the length of stay was 1 d (range, 0 to 22). These did not differ significantly by BMI group. Overall, 11.9% of patients experienced complications (7.9% minor, 4.1% major), and this did not differ significantly across BMI groups.

Conclusion:

Robotic hysterectomy can be performed safely in obese and morbidly obese patients, with surgical outcomes and complications similar to those in nonobese patients.     

Weight Gain After Primary Total Knee Arthroplasty Is Associated With Accelerated Time to Revision for Aseptic Loosening

BackgroundObesity is a major health problem worldwide and is associated with complications after total knee arthroplasty (TKA). It remains unknown whether a change in body mass index (BMI) after primary TKA affects the reasons for revision TKA or the time to revision TKA.MethodsA total of 160 primary TKAs referred to an academic tertiary center for revision TKA were retrospectively stratified according to change in BMI from the time of their primary TKA to revision TKA. The association between change in BMI and time to revision was also analyzed according to indication for revision of TKA using Pearson's chi-square test.ResultsThe mean change in BMI from primary to revision TKA was 0.82 ± 3.5 kg/m². Maintaining a stable weight after primary TKA was protective against late revision TKA for any reason (P = .004). Patients who failed to reduce their BMI were revised for aseptic loosening earlier, at less than 5 years (P = .020), whereas those who reduced their BMI were revised later, at over 10 years (P = .004).ConclusionMaintaining weight after primary TKA is protective against later revision TKA for any reason but failure to reduce weight after primary TKA is a risk factor for early revision TKA for aseptic loosening and osteolysis. Orthopedic surgeons should recommend against weight gain after primary TKA to reduce the risk of an earlier revision TKA in the event that a revision TKA is indicated.     

Braking Time Following Total Knee Arthroplasty: A Systematic Review

Background

Currently, no guidelines exist to assist surgeons in providing recommendations to patients undergoing total knee arthroplasty (TKA) on when it is safe to return to driving. The purpose of this systematic review is to analyze the best available literature to assist surgeons in providing evidence-based recommendations on when it is safe to return to driving after TKA.

Catastrophic Varus Collapse of the Tibia in Obese Total Knee Arthroplasty

Background

Mechanical complications have been underemphasized in reports on total knee arthroplasty (TKA) in obese patients. Noticing an increased prevalence of varus collapse of the tibia in obese total knee patients, we sought to determine if variability in proximal tibial cancellous bone strength played a role in failure. We attempted to define a cancellous threshold above which alternative methods of fixation should be used.

Cost-Effectiveness of Total Hip Arthroplasty Versus Nonoperative Management in Normal,Overweight, Obese,Severely Obese,Morbidly Obese,and Super Obese Patients: A Markov Model

Background

We estimated the cost-effectiveness of performing total hip arthroplasty (THA) vs nonoperative management (NM) among 6 body mass index (BMI) cohorts.

Patterns of Weight Change and Their Effects on Clinical Outcomes Following Total Knee Arthroplasty in an Asian Population

BackgroundThis prospective cohort study was designed to evaluate weight change patterns and their effects on clinical outcomes following total knee arthroplasty (TKA) in the Asian population. We hypothesized that Asian patients will have a different pattern of weight change following TKA compared to Western patients and that weight loss following TKA will be associated with better clinical outcomes.MethodsA cohort of consecutive patients who underwent TKA from 2004 to 2015 was included. All patients received a conventional posterior-stabilized TKA implant and underwent a standard perioperative care pathway. Assessments were done preoperatively, at 6 months, and 2 years after surgery. The range of motion, Knee Society Score, Oxford Knee Score, and the Short-Form 36 questionnaire were used to assess outcomes. Height and weight of patients were recorded for body mass index (BMI) calculation. Patterns of weight loss following TKA in this cohort were charted. Clinical outcomes were then analyzed against the change in BMI.ResultsA total of 602 patients (602 knees) were reviewed. Mean age was 66.39 ± 7.27 years. Mean BMI was 27.75 ± 4.51 kg/m². Overall, 63.12% of all our patients gained weight following TKA. Moreover, weight loss did not influence patients’ odds for better clinical outcomes. Furthermore, patients who were in the preoperative BMI category of obese class I were more likely to gain weight as compared to those in the normal category (odds ratio 0.35, 95% confidence interval 0.2-0.61, P < .001). Moreover, older people were more likely to gain more weight compared to younger people. We also showed that the mean 2-year Knee Society Knee Score was significantly higher in the patients who gained weight while the patients who lost weight had the highest mean 2-year Oxford Knee Score and the lowest mean 2-year Knee Society Function Score.ConclusionAsians tend to gain weight following TKA. However, this weight change following TKA does not affect clinical outcomes, which remain good across all BMI groups.Level of EvidenceTherapeutic Level III.     

Higher Body Mass Index Leads to Longer Operative Time in Total Knee Arthroplasty

Obesity has been shown to be a risk factor for degenerative knee arthritis and its incidence is increasing in epidemic proportions. Obesity has also been shown to be a risk factor for surgical complications associated with total knee replacement (TKR) surgery. There have been no prior investigations examining the relationship between body mass index (BMI) and surgical time during TKR. Two hundred and seventy three patients were evaluated and stratified by BMI. There was a direct linear relationship between BMI and operative time. In addition, the higher the BMI group, the younger the age at surgery, and obese class III patients experienced a higher rate of early post-operative complication. Therefore, patients should be counseled that obesity prior to TKR surgery might lead to a longer operative time and any sequelae associated with further exposure of the operative wound, especially with regard to higher rates of prosthetic joint infection (PJI).     

All-Cause In-Hospital Complications and Urinary Tract Infections Increased in Obese Patients Undergoing Total Knee Arthroplasty

The aims of this study were to determine the rates of in-hospital complications, discharge disposition, and length of stay for patients with varying degrees of obesity. We identified 4718 patients who underwent TKA between 2007 and 2010. After adjusting for age, sex, race, education, Deyo–Charlson comorbidity index, insurance, and discharge disposition, obese patients were more likely to develop any in-hospital complication (6.4% vs. 4.8%, respectively; P = 0.0097; OR = 1.5). When analyzing specific in-hospital complications, obese patients were more likely to suffer urinary tract infections (P = 0.0029). They were also more likely to be discharged to a rehabilitation facility (P = 0.001). There was no significant difference in other postoperative complications. In summary, obese patients undergoing primary TKA are at increased risk for all-cause in-hospital complications and urinary tract infections and are more likely to be discharged to a rehabilitation facility.     

Association Between Body Mass Index and Thirty-Day Complications After Total Knee Arthroplasty

Background

Although previous studies have evaluated the effect of obesity on the outcomes of total knee arthroplasty (TKA), most considered obesity as a binary variable. It is important to compare different weight categories and consider body mass index (BMI) as a continuous variable to understand the effects of obesity across the entire range of BMI. Therefore, the objective of this study is to analyze the effect of BMI on 30-day readmissions and complications after TKA, considering BMI as both a categorical and a continuous variable.

High Failure Rates for Unicompartmental Knee Arthroplasty in Morbidly Obese Patients: A Two-Year Minimum Follow-Up Study

BackgroundSeveral recent studies have recommended offering unicompartmental knee arthroplasty (UKA) to all patients regardless of body mass index (BMI). The aim of this investigation was to evaluate the proposition that UKA can indeed be offered to the morbidly-obese and super-obese (morbidly-obese, BMI ≥ 40 kg/m²) without compromising results or survivorship.MethodsWe retrospectively reviewed mobile-bearing medial UKA procedures performed at our facility from January 2012 to May 2015 with a minimum of 2-year follow-up. The study cohort was divided into patients with morbid obesity (BMI ≥ 40 kg/m²) and those without morbid obesity (BMI < 40 kg/m²). A detailed medical record review was performed. Extracted outcome data included the frequency of (1) major revision procedures (components revised), (2) minor secondary procedures (components not revised), (3) infection procedures, and (4) recommendations for revision.ResultsWe found 152 patients (190 knees) who met criteria for inclusion. Mean follow-up duration was 3.4 years (range: 2.0-6.8 years). Major revision surgery occurred more frequently in the morbid-obesity UKA group (15.7% vs 3.0%, P < .01). Rates of minor secondary surgery and infection were comparable for both groups. Most failures in the morbid-obesity UKA group (85.7%) were due to disease progression involving other compartments or mobile-bearing instability.ConclusionWe found the rate of early major revision surgery in morbidly-obese patients undergoing UKA to be over 5-times greater than that of other patients. Failure was predominantly due to disease progression in other compartments or mobile-bearing instability. Further study is warranted and needed before expanding UKA indications to the morbidly-obese population.     

The Increased Utilization of Operating Room Time in Patients with Increased BMI during Primary Total Hip Arthroplasty

While obesity is associated with increased need for total hip arthroplasty (THA), the relationship between body mass index (BMI) and operative duration is unknown. We reviewed a series of 425 primary THAs implanted by one surgeon from 2004 to 2010. Patients were grouped by BMI based on the World Health Organization's categorization. Intraoperative time measurements (Total Room Time, Anesthesia Induction Time, Surgery Time) were compared across groups. Mean times were analyzed using a one-way ANOVA with post-hoc least squares difference test. Operating time increased progressively with increasing BMI category. Significant differences were found between normal weight patients and all 3 obesity groups in total room and surgery times. Obese patients spend more time in the OR during THA, reflecting the burden obesity poses to surgeons and hospitals.     

人工膝关节置换术治疗重症膝关节疾病92例临床分析

目的探讨人工膝关节置换术(TKA)治疗重症膝关节疾病的临床疗效。方法1999年6月~2006年1月,对92例重症膝关节疾病(106膝)使用后稳定型TKA。其中10例(11膝)为类风湿性关节炎,2例(2膝)为创伤性关节炎,80例(93膝)为严重骨性关节炎,5例(5膝)合并外翻畸形,40例(50膝)并内翻畸形。所有患者进行10个月~6年(平均30个月)的随访,并应用HSS膝关节评分系统进行分析。结果手术优良率为94.2%,患者术后在疼痛、功能及关节活动度等方面都有明显改善,各种并发症的发生率低。结论TKA是治疗重症膝关节疾病的有效方法。     

Total Knee Replacement Arthroplasty with Buechel and Pappas Knee: Minimum 2-Year Follow-up

BackgroundClinical and radiologic evaluation and analyses of the surgeries using Buechel and Pappas (B-P) knee implants.MethodsThe study was conducted on 60 patients who underwent 94 total knee replacement arthroplasty with B-P knee implants from May 2009 to December 2010. The results were compared to the results of 41 patients who underwent 60 knee joint surgeries using NexGen-LPS implants from January 2008 to August 2009.ResultsThe American Knee Society score of the B-P knee group increased from an average of 66.9 (clinical score) and 65.5 (functional score) to 93.4 and 90.3, respectively; while those for the NexGen-LPS group increased from an average of 68.8 (clinical score) and 62.4 (functional score) to 86.3 and 76, respectively. The average ranges of motion of the B-P knee group and the NexGen-LPS group were 119.1° and 114.8°, respectively, before surgery and improved to 121.0° and 123.0° at final follow-up after the surgery. The visual analogue scale scores for the B-P knee group and the NexGen-LPS group improved from 4.7 and 4.6 to 1.4 and 1.8, respectively. The flexion contracture also improved from 5.1° and 6.3° to 0.64° and 1.72°. The tibio-femoral angle for the B-P knee group and the NexGen-LPS group also improved greatly after the surgery, from varus 0.34° and 0.73° each to valgus 6.7° and 6.9°, respectively.ConclusionsThe evaluation of more than 2 years of total knee replacement arthroplasty using B-P knee implants showed good results. B-P knee implants showed a relatively higher degree of satisfaction in clinical knee score and less intraoperative bone mass removal than NexGen-LPS implants.     

TKA is More Durable Than UKA for Morbidly Obese Patients: A Two-Year Minimum Follow-Up Study

BackgroundUnicompartmental knee arthroplasty (UKA) indications have expanded during the past two decades to include some morbidly obese patients (body mass index (BMI) > 40 kg/m²). Few published studies have compared UKA and total knee arthroplasty (TKA) in this unique patient subgroup with conflicting observations.MethodsWe retrospectively compared 89 mobile bearing UKA (71 patients) and 201 TKA (175 patients) performed at a single institution with a minimum 2-year follow-up (mean 3.4 years). Demographic characteristics were similar for both patient cohorts. A detailed medical record review was performed to assess the frequency of component revision, revision indications, minor secondary procedures (components retained), and infections.ResultsUKA was more frequently associated with clinical failure (29.2% vs 2.5%, P < .001) and component revision (15.7% vs 2.5%, P < .001), TKA was more frequently associated with extensor mechanism complications or knee manipulation (5.5% vs 0.0%, P = .02), and there was no difference in the infection rate (3.0% vs 2.2%, P = 1.0).ConclusionEarly complications were lower following UKA but were outweighed by higher component revision rates for arthritis progression and implant failure. The study findings suggest that TKA provides a more predictable mid-term outcome for morbidly obese patients considering knee arthroplasty surgery.