Risk factors for manipulation after total knee arthroplasty: a pooled electronic health record database study

Neighborhood socioeconomic disadvantage does not predict need for manipulation under anesthesia or range of motion following total knee arthroplasty

Background

Studies have linked socioeconomic factors including lower income and minority race with worse functional outcomes following total knee arthroplasty (TKA). Arthrofibrosis is a common complication following TKA, and manipulation under anesthesia (MUA) is an effective treatment option for arthrofibrosis. This study aimed to determine if neighborhood-level socioeconomic disadvantage predicts need for MUA and postoperative range of motion (ROM) among patients undergoing primary elective TKA.

Methods

We performed a retrospective cohort study of primary TKAs performed at a single institution over a three-year duration. Area Deprivation Index (ADI) was used to determine each patient's level of socioeconomic disadvantage based on their home address. Patients were allocated into three groups based on ADI: least socioeconomic disadvantage (ADI 1-3), middle socioeconomic disadvantage (ADI 4-6), and most socioeconomic disadvantage (ADI 7-10). Demographic factors and comorbid conditions were recorded. Bivariate analysis was used to evaluate the relationship between degree of socioeconomic disadvantage and need for MUA and postoperative ROM.

Results

In total, 600 patients were included and 26.7 % were categorized as most disadvantaged. In comparison to the middle and least disadvantaged groups, these patients were more likely to be Women (71.2 vs. 67.9 and 58.6 %; p = 0.027), younger (60.7 vs. 62.9 and 66.3 years; p < 0.001) and have higher BMI (34.9 vs. 33 and 31.7; p < 0.001) (most disadvantaged vs. middle and least). Analysis revealed no difference in rate of MUA (6.3 vs. 2.5 vs. 4 %; p = 0.179) or postoperative ROM (98 vs. 98 vs. 100°; p = 0.753) between the three groups (most, middle, and least disadvantaged, respectively).

Conclusion

Neighborhood socioeconomic disadvantage does not predict rate of MUA or postoperative ROM following TKA. Patients residing in neighborhoods with higher ADI who underwent TKA were more likely to be younger, Women, and have higher BMI, consistent with previous literature. Our results support efforts to improve access to orthopaedic care, including TKA, to patients of all socioeconomic levels.

Specific Preoperative Factors Increase Manipulations under Anesthesia Following Primary TKA

Arthrofibrosis following primary total knee arthroplasty (TKA) can result in pain and limit postoperative range of motion (ROM), jeopardizing clinical outcomes and patient satisfaction. This study aims to identify preoperative risk factors associated with necessitating a manipulation under anesthesia (MUA) following primary TKA.We retrospectively reviewed 950 cases of consecutive primary TKAs performed at one institution by three arthroplasty surgeons between May 2017 and May 2019. Recorded preoperative variables included smoking status, race, preoperative ROM, presence of effusion or positive anterior drawer, and medical comorbidities. Demographic characteristics were compared with Student's t-tests or chi-square tests as appropriate. For each preoperative factor, we obtained an odds ratio (OR) for MUA risk using multivariate logistic regression.Twenty (2.3%) patients underwent MUA following their index primary TKA surgery. History of ipsilateral knee surgery (OR: 2.727, p = 0.047) and diagnosed hypertension (OR: 4.764, p = 0.016) were identified as risk factors associated with significantly increased risk of MUA. The greater the preoperative ROM, the higher likelihood needed of MUA (OR: 1.031, p = 0.034).Patients who had diagnosed hypertension or a history of prior ipsilateral knee surgery were associated with increased risk of necessitating an MUA following primary TKA. Additionally, a greater total arc of motion preoperatively increased the odds of needing MUA.Level III of evidence was present.

Nearly 14-Fold Increased Risk of Manipulation Under Anesthesia After Total Knee Arthroplasty When Previous Contralateral Total Knee Arthroplasty Required Manipulation Under Anesthesia

BACKGROUND

Stiffness remains a common complication after primary total knee arthroplasty (TKA). Manipulation under anesthesia (MUA) is the gold standard treatment for early postoperative stiffness; however, there remains a paucity of data on the risk of MUA after primary TKA if a prior contralateral TKA required MUA.

METHODS

We performed a retrospective review of 3,102 patients who had staged primary TKAs between 2016 and 2021. The mean body mass index was 33 (range, 18 to 59) and the mean age was 67 years (range, 24 to 91). The mean preoperative range of motion for the first TKA was 2 to 104°, and for the contralateral TKA was 1 to 107°. The primary outcomes were MUA following first and second primary TKAs. Multivariable Poisson regressions were used to evaluate associations between risk factors and outcomes.

RESULTS

The rate of MUA after the first TKA was 2.6% (n = 83 of 3,102) and 1.3% (n = 40 of 3,102) after the contralateral TKA. After adjustment, there was a nearly 14-fold higher rate of MUA after the second TKA if the patient had an MUA after the first TKA (relative risk, 13.80; 95% CI [confidence interval], 7.14 to 26.66). For the first TKA, increasing age (adjusted risk ratio [ARR], 0.65; 95% CI, 0.50 to 0.83) and increasing body mass index (ARR, 0.65; 95% CI, 0.47 to 0.90) were associated with lower risk for MUA. For the second TKA, increasing age was associated with a lower risk of MUA (ARR, 0.60; 95% CI, 0.45 to 0.80).

CONCLUSIONS

For patients undergoing staged bilateral TKA, patients who undergo MUA following the first primary TKA are nearly 14-fold more likely to undergo an MUA following the contralateral primary TKA than those who did not have an MUA after their first TKA.

Shoulder Adhesive Capsulitis Prior to Total Knee Arthroplasty is Associated With Increased Rates of Postoperative Stiffness Requiring Manipulation Under Anesthesia and Arthroscopic Lysis of Adhesions

BACKGROUND

Arthrofibrosis following total knee arthroplasty (TKA) and adhesive capsulitis (AC) of the shoulder develop via a similar pathologic process. The purpose of this study was to examine the relationship between these two conditions.

METHODS

This was a retrospective cohort study using a large nationwide claims database. Patients who had a history of shoulder AC prior to TKA were compared to TKA patients who did not have AC history comparing rates of postoperative stiffness, manipulation under anesthesia (MUA), arthroscopic lysis of adhesions (LOAs), and revision arthroplasty at postoperative timepoints (3 months, 6 months, 1 year, and 2 years).

RESULTS

Within 3 months, 6 months, 1 year, and 2 years of their TKAs, patients who had a history of AC prior to TKA were significantly more likely to experience stiffness (OR [odds ratio] = 1.29, 1.28, 1.32, and 1.36, respectively) and LOAs (OR = 6.78, 3.65, 2.99, and 2.81, respectively). They also showed increased risk of MUA within 6 months, 1 year, and 2 years (OR = 1.15, 1.15, and 1.16, respectively) of their TKAs. Patients having a preoperative diagnosis of AC did not have an increased risk of undergoing revision surgery 1 year or 2 years after their TKAs (P > .05).

CONCLUSIONS

Patients diagnosed with AC prior to TKA experience higher rates of postoperative stiffness, resulting in additional interventions such as MUA and LOAs. These findings identify a particularly high-risk patient population that may benefit from additional interventions prior to and following TKA.

LEVEL OF EVIDENCE

This is a level III prognostic study.

Hemoglobin A1c Levels >6.6% Are Associated With Higher Postoperative Complications After Anterior Cruciate Ligament Reconstruction

Purpose

To investigate the relation between hemoglobin A1c (HbA1c) levels and postoperative complications after primary anterior cruciate ligament reconstruction (ACLR).

Methods

A retrospective review was performed of consecutive patients with an isolated anterior cruciate ligament tear, preoperative diagnosis of diabetes, and documented HbA1c within 90 days of primary ACLR between 2000 and 2019. Data collected included demographic and surgical characteristics, 90-day medical complications, and subsequent surgeries on the ipsilateral knee. A receiver operating curve was constructed for each HbA1c level in relation to postoperative complications and the optimal cutoff identified via Youden's J statistic. Multivariable logistic regression was performed to assess the relation between postoperative complications and age, sex, graft type, diabetes subtype, and HbA1c.

Results

Nineteen patients (7 females, 12 males) fulfilled inclusion criteria with preoperative HbA1c ranging from 5.5 to 10. Complications included septic knee (n = 1) and cyclops lesions requiring arthroscopic lysis (n = 3). Patients with HbA1c of 6.7% or higher were 25 times more likely to experience any postoperative complication (P = .04) and 16 times more likely to require lysis of adhesions (P = .08). On multivariable regression, HbA1c remained significantly associated with any complication (P = .005) and developing arthrofibrosis (P = .02) independent of age, sex, graft type, and diabetes subtype.

Conclusions

Diabetic patients undergoing primary ACLR with a preoperative HbA1c of 6.7% or higher were 25 times more likely to require repeat surgical intervention for a postoperative complication. These complications included arthrofibrosis and infection. Strict glycemic control may help minimize the risk of postoperative complications after ACLR.

Level of Evidence

Level III, retrospective cohort study.

Utilization of Total Joint Arthroplasty by Rural-Urban Designation in Patients With Osteoarthritis in a Universal Coverage System

BACKGROUND

Utilization of total joint arthroplasty (TJA) is affected by differences linked to sex, race, and socioeconomic status; there is little information about how geographic variation contributes to these differences. We sought to determine whether discrepancies in TJA utilization exist in patients diagnosed with osteoarthritis (OA) based upon urban-rural designation in a universal coverage system.

METHODS

We conducted a cohort study using data from a US-integrated healthcare system (2015 to 2019). Patients aged ≥50 years who had a diagnosis of hip or knee OA were included. Total hip arthroplasty and total knee arthroplasty utilization (in respective OA cohorts) was evaluated by urban-rural designation (urban, mid, and rural). Incidence rate ratios (IRRs) for urban-rural regions were modeled using multivariable Poisson regressions.

RESULTS

The study cohort included 93,642 patients who have hip OA and 275,967 patients who had knee OA. In adjusted analysis, utilization of primary total hip arthroplasty was lower in patients living in urban areas (IRR = 0.87, 95% confidence interval = 0.81 to 0.94) compared to patients in rural regions. Similarly, total knee arthroplasty was used at a lower rate in urban areas (IRR = 0.88, 95% confidence interval = 0.82 to 0.95) compared with rural regions. We found no differences in the hip and knee groups within the mid-region.

CONCLUSIONS

In hip and knee OA patients enrolled in a universal coverage system, we found patients living in urban areas had lower TJA utilization compared to patients living in rural areas. Further research is needed to determine how patient location contributes to differences in elective TJA utilization.

LEVEL OF EVIDENCE

III.

Does interaction occur between risk factors for revision total knee arthroplasty?

INTRODUCTION

Several risk factors for revision TKA have previously been identified, but interactions between risk factors may occur and affect risk of revision. To our knowledge, such interactions have not been previously studied. As patients often exhibit multiple risk factors for revision, knowledge of these interactions can help improve risk stratification and patient education prior to TKA.

MATERIALS AND METHODS

The State Inpatient Databases (SID), part of the Healthcare Cost and Utilization Project (HCUP), were queried to identify patients who underwent TKA between January 1, 2006 and December 31, 2015. Risk factors for revision TKA were identified, and interactions between indication for TKA and other risk factors were analyzed.

RESULTS

Of 958,944 patients who underwent TKA, 33,550 (3.5%) underwent revision. Age, sex, race, length of stay, Elixhauser readmission score, urban/rural designation, and indication for TKA were significantly associated with revision (p < 0.05). Age was the strongest predictor (p  < 0.0001), with younger patients exhibiting higher revision risk. Risks associated with age were modified by an interaction with indication for TKA (p < 0.0001). There was no significant interaction between sex and indication for TKA (p = 0.535) or race and indication for TKA (p = 0.187).

CONCLUSIONS

Age, sex, race, length of stay, Elixhauser readmission score, urban/rural designation, and indication for TKA are significantly associated with revision TKA. Interaction occurs between age and indication.

Manipulation Under Anesthesia and/or Lysis of Adhesions After Anterior Cruciate Ligament Reconstruction in Female Basketball Players: Does Race Play a Role?

BACKGROUND

Arthrofibrosis can limit function and return to sport after anterior cruciate ligament (ACL) reconstruction. Previously reported risk factors for developing arthrofibrosis after ACL reconstruction include female sex, age <18 years, time from injury to surgery <28 days, concomitant meniscal repair, prolonged immobilization, and genetic factors. There is a lack of evidence regarding whether race plays a significant role.

HYPOTHESIS

The risk of undergoing manipulation under anesthesia (MUA) and/or lysis of adhesions (LOA) after primary ACL reconstruction with bone-patellar tendon-bone (BTB) autograft in female basketball players is higher in African American players than in White players.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Using a computerized relational database, the authors identified competitive female basketball players who underwent primary ACL reconstruction with BTB autograft by the senior author over a 13-year period. Data previously entered from examinations and surgical findings were reviewed retrospectively. Univariate statistics and multivariable logistic regression were used to assess the relationship between undergoing subsequent MUA and/or LOA and study predictors.

RESULTS

A total of 186 knees (114 African American knees and 72 White knees) met inclusion criteria. The overall rate of MUA and/or LOA was 8.6%. Thirteen African American knees (11.4%) and 3 White knees (4.2%) underwent MUA and/or LOA for treatment of arthrofibrosis. No study predictor was found to have a statistically significant relationship with the rate of MUA and/or LOA on univariate analysis. However, when controlling for body mass index and previously described risk factors (age <18 years, time from injury to surgery ≤28 days, and concomitant meniscal repair) in the logistic regression model, the authors found that MUA and/or LOA was more likely in African American (odds ratio, 4.01 [95% CI, 1.01-15.92]; P = .049) than in White female players and in patients who underwent ACL reconstruction within 28 days of injury (odds ratio, 4.01 [95% CI, 1.18-13.57]; P = .026) compared with those with surgery delayed beyond 28 days.

CONCLUSION

In female basketball players, the present study found a statistically significantly increased risk for undergoing MUA and/or LOA after primary ACL reconstruction with BTB autograft in African American females compared with White females and in patients who underwent ACL reconstruction within 28 days of injury.

HSP90B1-mediated plasma membrane localization of GLUT1 promotes radioresistance of glioblastomas

Ionizing radiation is a popular and effective treatment option for glioblastoma (GBM). However, resistance to radiation therapy inevitably occurs during treatment. It is urgent to investigate the mechanisms of radioresistance in GBM and to find ways to improve radiosensitivity. Here, we found that heat shock protein 90 beta family member 1 (HSP90B1) was significantly upregulated in radioresistant GBM cell lines. More importantly, HSP90B1 promoted the localization of glucose transporter type 1, a key rate-limiting factor of glycolysis, on the plasma membrane, which in turn enhanced glycolytic activity and subsequently tumor growth and radioresistance of GBM cells. These findings imply that targeting HSP90B1 may effectively improve the efficacy of radiotherapy for GBM patients, a potential new approach to the treatment of glioblastoma.

Manipulation Following Primary Total Knee Arthroplasty is Associated With Increased Rates of Infection and Revision

BACKGROUND

Stiffness following total knee arthroplasty (TKA) is a disabling complication and manipulation under anesthesia (MUA) is often performed as an early intervention. Few studies have focused on the revision risk, infection risk, demographics, and clinical outcomes in Medicare patients undergoing MUA following primary TKA.

METHODS

We reviewed 142,440 patients who had primary TKA from a national database and identified 3,652 patients (2.6%) who underwent MUA. Patient demographics and comorbid conditions were evaluated to identify risk factors. Incidence of revision and periprosthetic joint infection (PJI) at 1-, 2-, and 5-year time points in a cohort of MUA patients was compared to patients who did not undergo MUA. Multivariate Cox regressions were used for statistical analyses.

RESULTS

The incidence of MUA was higher in Black versus White individuals (4.1 versus 2.5%, P < .001). Revision risk was significantly greater in the MUA group at 1-, 2-, and 5-year time points with a hazard ratio (HR) of, 3.81, 3.90, and 3.22 respectively, P < .001. One- and 2-year revision risk was significantly greater when MUA occurred at 6 to 12 months post-TKA when compared to <3 months, P < .05. Risk of PJI was significantly greater in the MUA group with a HR of 2.2, 2.2, and 2.1 at 1, 2, and 5 years, respectively P < .001.

CONCLUSION

The incidence of MUA was 2.6%. There was an increased incidence of revision surgery and PJI in patients undergoing MUA. Patients at increased risk for stiffness following TKA should be closely monitored and treated with early intervention to minimize risk of poor outcomes.

Early manipulation under anaesthesia for stiffness following total knee arthroplasty is associated with a greater gain in knee flexion

PURPOSE

This study aimed to identify the risk factors for manipulation under anaesthesia (MUA) following total knee arthroplasty (TKA) and whether performing an 'early' MUA within 3 months leads to a greater improvement in range of motion.

METHODS

Primary TKAs performed between 2013 and 2018 at three tertiary New Zealand hospitals were reviewed with a minimum follow-up of 1 year. Clinical details of patients who underwent MUA were reviewed to identify the knee flexion angle prior to and following MUA. Multivariate analysis identified the risk factors for undergoing MUA and compared flexion angles between 'early' (< 3 months) and 'late' MUA (> 3 months).

RESULTS

A total of 7386 primary TKAs were analysed in which 131 underwent an MUA (1.8%). Patients aged < 65 years were two times more likely to undergo MUA compared to patients aged ≥ 65 years (2.5 versus 1.3%, p < 0.001; adjusted HR = 2.1, p < 0.001). There was no difference in the final flexion angle post-MUA between early and late MUA (104.7° versus 104.1°, p = 0.819). However, patients who underwent early MUA had poorer pre-MUA flexion (72.3° versus 79.6°, p = 0.012), and subsequently had a greater overall gain in flexion compared to those who underwent late MUA (mean gain 33.1° versus 24.3°, p < 0.001).

CONCLUSION

Younger age was the only patient risk factor for MUA. Patients who underwent early MUA had similar post-MUA flexion, but had poorer pre-MUA flexion compared to those who underwent late MUA. Subsequently, a greater overall gain in flexion was achieved in those who underwent early MUA.

LEVEL OF EVIDENCE

III.

Understanding rates, risk factors, and complications associated with manipulation under anesthesia after total knee arthroplasty (TKA): An analysis of 100,613 TKAs

BACKGROUND

Considering the growing adoption of technology-assisted total knee arthroplasties (TKA), previous database studies evaluating post-operative stiffness may be outdated. The present study aimed to: (1) evaluate the incidence of manipulation under anesthesia (MUA) after primary TKA; (2) determine independent risk factors for MUA; and (3) assess complications after MUA.

METHODS

Primary TKAs, with at least 6-month follow-up, were identified from the Florida State Inpatient Database (January 2016-June 2018) and linked to outpatient records from the Florida State Ambulatory Surgery and Services Database. Multivariable regression analyses were performed to compare patient factors and complications (e.g., mechanical, non-mechanical, infectious) associated with MUA, while adjusting for baseline demographics, comorbidities, use of robotic- and computer-technologies, time to MUA (0-3, 3-12, or >12 months), and need for repeat MUA (one-time vs >1).

RESULTS

The MUA rate was 2.8% (2821 of 100,613). Being younger, a woman, Black or Hispanic; having private or self-pay insurance; and conventional TKA were associated with significantly higher odds of undergoing MUA. Higher rates of mechanical complications and acute posthemorrhagic anemia were observed in the MUA cohort. Time to MUA, repeat MUA, and baseline demographics were not associated with complication rates among the MUA cohort.

CONCLUSION

Overall, 1 in 36 patients underwent MUA after primary TKA. Several non-modifiable patient characteristics, such as Black or Hispanic race, female sex, and younger age were associated with an increased risk of MUA. However, technology-assisted TKA might help to decrease the risk of MUA.

Racial Differences in Manipulation Under Anesthesia Rates Following Total Knee Arthroplasty

BACKGROUND

Despite the extensive literature on racial disparities in care and outcomes after total knee arthroplasty (TKA), data on manipulation under anesthesia (MUA) is lacking. We aimed to determine (1) the relationship between race and rate of (and time to) MUA after TKA, and (2) annual trends in racial differences in MUA from 2013 to 2018.

METHODS

This retrospective cohort study (using 2013-2018 Medicare Limited Data Set claims data) included 836,054 primary TKA patients. The primary outcome was MUA <1 year after TKA; time from TKA to MUA in days was also recorded. A mixed-effects multivariable model measured the association between race (White, Black, Other) and odds of MUA. Odds ratios (OR) and 95% confidence intervals (CI) were reported. A Cochran Armitage Trend test was conducted to assess MUA trends over time, stratified by race.

RESULTS

MUA after TKA occurred in 1.7%, 3.2% and 2.1% of White, Black, and Other race categories, respectively (SMD = 0.07). After adjustment for covariates, (Black vs White) patients had increased odds of requiring an MUA after TKA: odds ratio (OR) 1.97, 95% confidence intervals (CI) 1.86-2.10, P < .0001. Moreover, White (compared to Black) patients had significantly shorter time to MUA after TKA: 60 days (interquartile range [IQR] 46-88) versus 64 days (interquartile range [IQR] 47-96); P < .0001. These disparities persisted from 2013 through 2018.

CONCLUSION

Continued racial differences exist for rates and timing of MUA following TKA signifying the continued need for efforts aimed toward understanding and eliminating inequalities that exist in total joint arthroplasty (TJA) care.

Efficacy of non-operative treatment of patients with knee arthrofibrosis using high-intensity home mechanical therapy: a retrospective review of 11,000+ patients

Background

Recovery from knee surgery or injury can be hindered by knee arthrofibrosis, which can lead to motion limitations, pain and delayed recovery. Surgery or prolonged physical therapy are often treatment options for arthrofibrosis, but they can result in increased costs and decreased quality of life. A treatment option that can regain lost motion without surgery would help minimize risks and costs for the patient. The purpose of this study was to determine treatment efficacy of high-intensity home mechanical stretch therapy in patients with knee arthrofibrosis.

Methods

Records were reviewed for 11,000+ patients who were prescribed a high-intensity stretch device to regain knee flexion. Initial and last recorded knee flexion and days between measurements were available for 9842 patients (Dataset 1). Dataset 2 was a subset of 966 patients from Dataset 1. These 966 patients had separate more rigorous measurements available from physical therapy notes (Dataset 3) in addition to data from the internal database (Dataset 2). Within and between dataset statistics were calculated using t tests for comparison of means and Cohen’s d for determination of effect size.

Results

All dataset showed significant gains in flexion (p < 0.01). Mean initial flexion, last recorded flexion and flexion gain were 79.5°, 108.4°, and 29.9°, respectively in Dataset 1. Differences between Datasets 2 and 3 had small effect sizes (Cohen’s d < 0.17). The were no significant differences when comparing workers’ compensation and non-workers’ compensation patients. The average last recorded flexion for all datasets was above the level required to perform activities of daily living. Motion gains were recorded in under 60 days from device delivery.

Conclusions

High-intensity home mechanical stretch therapy was effective in restoring knee flexion, generally in 2 months or less, and in avoiding additional surgery in severe motion loss patients regardless of sex, age, or workers’ compensation status. We believe high-intensity stretching should be considered in any patient who is at risk for a secondary motion loss surgery, because in over 90% of these patients, the complications and costs associated with surgery can be avoided.

Aspirin Administered for Venous Thromboembolism Prophylaxis May Protect Against Stiffness Following Total Knee Arthroplasty

BACKGROUND

Aspirin has become the main agent for venous thromboembolism (VTE) prophylaxis following total knee arthroplasty (TKA). This study assessed whether aspirin is associated with less knee stiffness compared to warfarin and other chemoprophylaxis agents.

METHODS

This is a retrospective review of all primary and revision TKAs performed between January 2009 and October 2020 at a high volume institution. Demographics, comorbidity data, and operative variables were extracted from medical records. VTE prophylaxis administered during this time period included aspirin, warfarin, and "others" (factor Xa, unfractionated heparin, low-molecular-weight heparin, fondaparinux, adenosine diphosphate receptor inhibitor, and direct thrombin inhibitor). The primary outcome assessed was manipulation under anesthesia (MUA) performed within 6 months of index surgery. Secondary outcome included major bleeding events. Univariate followed by multivariate regression analyses were performed.

RESULTS

A total of 15,903 cases were included in the study, of which 531 (3.3%) patients developed stiffness that required MUA. The rates of MUA were 2.7% (251/9223) for patients receiving aspirin, 4.2% (238/5709) for patients receiving warfarin, and 4.3% (42/971) for all others (P's < .001). Multivariate regression analysis confirmed that aspirin is associated with lower rates of VTE compared to warfarin (adjusted odds ratio 1.423, 95% confidence interval 1.158-1.747, P < .001) and compared to other anticoagulation medications (adjusted odds ratio 1.742, 95% confidence interval 1.122-2.704, P = .013). Major bleeding events were also significantly lower in patients who received aspirin compared to the other 2 groups (P's = .001).

CONCLUSION

Aspirin prophylaxis is associated with lower rates of MUA following TKA compared to warfarin and other VTE chemoprophylactic agents when grouped together.

The Epidemiology of Annular Pancreas in the United States: A Population-based Study

BACKGROUND AND AIMS

Annular pancreas is a rare congenital condition where the second part of the duodenum is encircled by pancreatic tissue. There is a scarcity of data on its natural history therefore, we aimed to evaluate the epidemiology of annular pancreas and identify underlying associations using a large database.

METHODS

A multi-institutional database (Explorys) was surveyed. A cohort of patients with a Systematized Nomenclature of Medicine-Clinical Terms diagnosis of "MRI, CT, EUS and/or ERCP" between April 2015 and April 2020 was identified. Subsequently a cohort of patients with history of "annular pancreas" was identified.

RESULTS

There were a total of 40,075,980 individuals in the database with 6,162,600 (15.38%) who had an magnetic resonance imaging, computed tomography, endoscopic retrograde cholangiopancreatography, and/or endoscopic ultrasound. There were 210 (3.4/100,000) had a diagnosis of annular pancreas. When compared with the control group, patients with annular pancreas were more likely to have a history of alcohol use, smoking, acute pancreatitis, chronic pancreatitis, gastritis, duodenitis, jaundice, and gastrointestinal outlet obstruction.

CONCLUSIONS

This is the largest study evaluating the epidemiology of annular pancreas. We found the estimated prevalence rate of annular pancreas to be 3.4/100,000 in those who had abdominal imaging. Annular pancreas was more likely to be diagnosed in patients with symptoms pertaining to acute or chronic pancreatitis, biliary, and gastric outlet obstruction.

Outcomes of Total Joint Arthroplasty in Black, Asian, Minority Ethnic Groups Versus Local Population: A Retrospective Review

BACKGROUND

 Total hip and knee replacement decrease the disability caused by osteoarthritis of the lower extremities. Although it has been established that racial and ethnic minorities underutilize these procedures, little data on postoperative outcomes exists. The impact of race on postoperative Oxford scores and complications following total joint arthroplasty (TJA) will be investigated in this retrospective review.

METHODS

 A retrospective review of 120 elective primary TJA procedures was undertaken between January 2016 and December 2019 in a single institution. To measure variations between the various groups, t-tests were used on their Oxford scores, and chi-squared bivariate regression was used to classify all categorical variables and the association of ethnicity and surgery type with gender.

RESULTS

 There were 62 (51.6%) White patients and 59 (49.1.0%) Black, Asian, Minority Ethnic (BAME) patients in total. The majority of the patients were females (60.9% vs 39.2%, p = 0.032). Low vitamin D levels were seen in a small percentage of patients in the sample (15.8% vs 84.2%, p = 0.460). There is a statistically important connection (p = 0.001) between the surgery type (total knee replacement [TKR]/total hip replacement [THR]) and gender; 41 females had TKR surgery, and 32 had THR surgery.

CONCLUSION

The study found that the relationships between ethnicity (White/BAME) and gender as well as surgery type (TKR/THR) and gender are statistically important. In all cases with low vitamin D and normal vitamin D levels, White patients had higher overall Oxford hip scores than the BAME patients. To comprehend the differences discovered, further research is needed. To try to eliminate the difference, targeted approaches should be created.

Predicting critical state after COVID-19 diagnosis: model development using a large US electronic health record dataset

As the COVID-19 pandemic is challenging healthcare systems worldwide, early identification of patients with a high risk of complication is crucial. We present a prognostic model predicting critical state within 28 days following COVID-19 diagnosis trained on data from US electronic health records (IBM Explorys), including demographics, comorbidities, symptoms, and hospitalization. Out of 15753 COVID-19 patients, 2050 went into critical state or deceased. Non-random train-test splits by time were repeated 100 times and led to a ROC AUC of 0.861 [0.838, 0.883] and a precision-recall AUC of 0.434 [0.414, 0.485] (median and interquartile range). The interpretability analysis confirmed evidence on major risk factors (e.g., older age, higher BMI, male gender, diabetes, and cardiovascular disease) in an efficient way compared to clinical studies, demonstrating the model validity. Such personalized predictions could enable fine-graded risk stratification for optimized care management.

Angiotensin Receptor Blockers Were Not Associated With Decreased Arthrofibrosis After Total Knee Arthroplasty

Stiffness after total knee arthroplasty (TKA) remains a challenging problem. Angiotensin receptor blockers (ARBs) have been associated with decreased muscle fibrosis. The aim of this study was to evaluate whether perioperative use of ARBs was associated with a reduction in arthrofibrosis and manipulation under anesthesia (MUA) in patients undergoing primary TKA at 90 days and 1 year postoperative. In this retrospective study, the authors used a national database to evaluate patients undergoing TKA for primary osteoarthritis from 2007 to 2017. They evaluated patients with filled prescriptions for ARBs within the study time frame and the specific type of ARB and its association with arthrofibrosis and MUA. After adjusting for age, sex, a comorbidity index, and obesity, any ARB or specific ARBs were not associated with a reduction in the rate of arthrofibrosis or MUA after TKA (P≥.05). Male sex, age 55 years or older, and obesity were associated with a reduction in the rate of arthrofibrosis and MUA after TKA (P≤.05). Studies should be performed to evaluate ARBs to see whether there is a more specific role in preventing joint stiffness in certain patient subpopulations following TKA. [Orthopedics. 2021;44(2):e274-e280.].

Role of real-world digital data for orthopedic implant automated surveillance: a systematic review

INTRODUCTION

Data collection automation through the reuse of real-world digital data from clinical data warehouses (CDW) could represent a great opportunity to improve medical device monitoring. For instance, this approach is starting to be used for the design of automated decision support systems for joint replacement monitoring. However, a number of obstacles remains, such as data quality and interoperability through the use of common and regularly updated terminologies, and the use of a Unique Device Identifier (UDI).

AREAS COVERED

To present the existing models of automated surveillance of orthopedic devices, a systematic review of initiatives using real-world digital health data to monitor joint replacement surgery was performed following the PRISMA 2020 guidelines. The main objective was to identify the data sources, the target populations, the population size, the device location, and the main results of studies on such initiatives.

EXPERT OPINION

Analysis of the identified studies showed that real-world digital data offer many opportunities for improving the automation of monitoring in orthopedics. The contribution of real-world data, especially through natural language processing, UDI use in CDW and the integration of device databases, is needed for automated and more robust health surveillance.

Reduction of Opioid Quantities at Discharge After TKA Did Not Increase the Risk of Manipulation Under Anesthesia: An Institutional Experience

BACKGROUND

In response to the opioid epidemic, our arthroplasty service sequentially reduced the opioid quantities prescribed at primary total knee arthroplasty (TKA) discharge. However, its effect on postdischarge pain control and rehabilitation is unknown. We assessed if this decrease was associated with an increase in the risk of manipulation under anesthesia (MUA).

METHODS

We retrospectively reviewed 8799 patients undergoing primary TKA from 2016 to 2019 at a single institution. There were two institution-wide reductions in the amount of opioids prescribed at discharge; therefore, we divided patients into 3 periods (P1, P2, and P3). The mean discharge morphine milligram equivalents (MMEs) went from 900 MMEs to ~525 MMEs to ~320 MMEs in P1, P2, and P3, respectively. We analyzed MUA rates and if lower discharge MMEs was a risk factor for MUA in a multivariate model. We also compared refill patterns (rates, number, refill MMEs, and total MMEs) between MUA and non-MUA patients.

RESULTS

The rate of MUA did not increase with reduced discharged opioids (5.5% in P1, 5.8% in P2, and 4.6% in P3, P = .74). In a multivariate analysis, discharge MMEs of <450 was not a significant risk factor for MUA. However, a diagnosis of chronic pain (OR = 1.86, P < .001) and an elevated body mass index (OR = 1.02 per unit increase, P < .001) were significant risk factors. We did not find significant differences in any opioid prescription refill patterns in MUA and non-MUA patients.

CONCLUSION

Serial reductions in discharge MMEs after primary TKA did not significantly affect the rate of MUA, a surrogate marker for pain control and the rehabilitative process.

Assessment of Racial Disparities in the Risks of Septic and Aseptic Revision Total Knee Replacements

Importance

Black patients are at higher risk of revision total knee replacement (TKR) than White patients, but whether racial disparities exist for both septic and aseptic revision TKR and the reason for any disparities are unknown.

Objective

To assess the risk of septic and aseptic revision TKR in Black and White patients and to examine interactions among race and socioeconomic and hospital-related variables that are associated with revision TKR risk.

Design, Setting, and Participants

This cohort study included residents of New York, California, and Florida who underwent TKR. Patient-level data were obtained from the New York Statewide Planning and Research Cooperative System, California's Office of Statewide Health Planning and Development Patient Discharge Database, and Florida's Healthcare Utilization Project State Inpatient Database from January 1, 2004, to December 31, 2014. Community characteristics were calculated from the US Census and linked to discharges by patient zip code. American Hospital Association Annual Survey data were linked to discharges using hospital identifiers. The analyses were performed from March 1 to October 30, 2020, with subsequent analyses in April 2021.

Main Outcomes and Measures

Cox proportional hazards regression modeling was used to measure the association of race with septic and aseptic revision TKR.

Results

A total of 722 492 patients underwent primary TKR, of whom 445 616 (61.68%) were female and 61 092 (8.46%) were Black. Black patients were at higher risk of septic (hazard ratio [HR], 1.11; 95% CI, 1.03-1.20) and aseptic (HR, 1.39; 95% CI, 1.33-1.46) revision TKR compared with White patients. Other risk factors for septic revision TKR were diabetes (HR, 1.24; 95% CI, 1.17-1.30), obesity (HR, 1.13; 95% CI, 1.17-1.30), kidney disease (HR, 1.42; 95% CI, 1.29-1.57), chronic obstructive pulmonary disease (HR, 1.22; 95% CI, 1.15-1.30), inflammatory arthritis (HR, 1.53; 95% CI, 1.39-1.69), surgical site complications during the index TKR (HR, 2.19; 95% CI, 1.87-2.56), Medicaid insurance (HR, 1.17; 95% CI, 1.04-1.31), and low annual TKR volume at the hospital where the index TKR was performed (HR, 1.54; 95% CI, 1.41-1.68). Risk factors for aseptic revision TKR were male sex (HR, 1.03; 95% CI, 1.00-1.06), workers' compensation insurance (HR, 1.61; 95% CI, 1.51-1.72), and low hospital TKR volume (HR, 1.14; 95% CI, 1.07-1.22). Patients with obesity had a lower risk of aseptic TKR revision (HR, 0.81; 95% CI, 0.77-0.84). In an analysis within each category of hospital TKR volume, the HR for aseptic revision among Black vs White patients was 1.20 (95% CI, 1.04-1.37) at very-low-volume hospitals (≤89 TKRs annually) compared with 1.68 (95% CI, 1.48-1.90) at very-high-volume hospitals (≥645 TKRs annually).

Conclusions and Relevance

In this cohort study, Black patients were at significantly higher risk of aseptic revision TKR and, to a lesser extent, septic revision TKR compared with White patients. Racial disparities in aseptic revision risk were greatest at hospitals with very high TKR volumes.

Pancreatic manifestations in rheumatoid arthritis: a national population-based study

OBJECTIVES

RA is a systemic autoimmune disease characterized by persistent joint inflammation. Extra-articular manifestations of RA can involve different organs including the gastrointestinal (GI) system. Using a large database, we sought to describe the epidemiology of pancreas involvement in RA.

METHODS

We queried a multicentre database (Explorys Inc, Cleveland, OH, USA), an aggregate of electronic health record data from 26 major integrated US healthcare systems in the US from 1999 to 2019. After excluding patients younger than 18, a cohort of individuals with Systematized Nomenclature of Medicine - Clinical Terms (SNOMED-CT) diagnosis of RA was identified. Within this cohort, patients who developed a SNOMED-CT diagnosis of acute pancreatitis (AP), chronic pancreatitis (CP) and primary pancreatic cancer (PaCa) after at least 30 days of RA diagnosis were identified. Statistical analysis for multivariate model was performed using Statistical Package for Social Sciences (SPSS version 25, IBM Corp) to adjust for several factors.

RESULTS

Of the 56 183 720 individuals in the database, 518 280 patients had a diagnosis of RA (0.92%). Using a multivariate regression model, patients with RA were more likely to develop AP [odds ratio (OR): 2.51; 95% CI: 2.41, 2.60], CP (OR: 2.97; 95% CI: 2.70, 3.26) and PaC (OR: 1.79; 95% CI: 1.52, 2.10).

CONCLUSION

In this large database, we found a modest increased risk of AP and CP among patients with RA after adjusting for the common causes of pancreatitis. Further studies are required to better understand this association and the effect of medications used for RA.

Lower Rates of Colorectal Cancer in Patients With Inflammatory Bowel Disease Using Anti-TNF Therapy

BACKGROUND

Chronic inflammation is a key factor for the development of colorectal cancer (CRC) among patients with inflammatory bowel disease (IBD). Despite the increased use of biologic agents in patients with IBD, their impact on colorectal carcinogenesis remains unclear. With the use of a large database, we sought to describe the effect of biologics on CRC among patients with IBD.

METHODS

We evaluated a multicenter database (Explorys) consisting of electronic medical records from several U.S. hospitals between 1999 and 2020. A cohort of patients with a diagnosis of IBD was identified. We performed a multivariate analysis to adjust for multiple factors including medical and surgical therapies.

RESULTS

There were a total of 62,007,510 patients in the database between 1999 and 2020. Amongst those, 225,090 (0.36%) individuals had Crohn's disease and 188,420 (0.30%) had ulcerative colitis. After adjusting for confounding factors using multivariate analysis, patients with IBD were more likely to develop CRC. Among the IBD cohort, patients treated with anti-TNF agents were less likely to develop CRC; patients with Crohn's disease: odds ratio, 0.69; 95% confidence interval, 0.66-0.73; P < 0.0001 vs patients with ulcerative colitis: odds ratio, 0.78; 95% confidence interval, 0.73-0.83; P < 0.0001.

CONCLUSIONS

Patients with IBD who were treated with anti-tumor necrosis factor agents were less likely to develop CRC. Prospective studies are needed to evaluate whether anti-tumor necrosis factor drugs provide a chemoprotective effect in patients with IBD by inflammation control and mucosal healing.

Manipulation under Anesthesia after Knee Arthroplasty Is Associated with Worse Long-Term Clinical Outcomes and Survivorship

The literature is mixed on the long-term fate of knees that undergo manipulation under anesthesia (MUA). The purpose of this study is to evaluate the long-term outcomes and survivorship of patients who required a MUA after primary total knee arthroplasty (TKA) compared with a cohort of patients who did not undergo a MUA. Between 2003 and 2007, 2,193 patients (2,783 knees) underwent primary TKA with 2-year minimum follow-up; 182 knees (6.5%) had a MUA. Patients who had a manipulation were younger (p < 0.001) and had worse preoperative range of motion (ROM) (p < 0.001). Postoperative ROM, Knee Society clinical (KSC), functional, and pain (KSP) scores, revisions, and survivorship were compared between MUA and no MUA. Mean follow-up was 9.7 years. MUA patients had lower postoperative ROM (p < 0.001), change in ROM (p < 0.001), KSC (p < 0.001), KSP (p < 0.001), and change in KSP scores (0.013). Revisions occurred in 18 knees (9.9%) in the MUA group compared with 77 knees (3%) without a MUA (p < 0.001). Most common reason for revision after MUA was continued stiffness (50%). Relative risk for revision after one MUA was 2.01 (95% confidence interval [CI], 1.1-3.8, p < 0.001) and after three or more MUAs were 27.02 (95% CI, 16.5-44.1, p < 0.001). Ten-year survival after MUA was 89.4% (95% CI, 87.1-91.7%) compared with 97.2% (95% CI, 96.9-97.5%) without a MUA (p < 0.001). Patients who undergo a MUA after primary TKA may have a knee at risk with higher revision rates, worse long-term clinical scores, ROM and survivorship.

Prior Knee Arthroscopy Increases the Failure Rate of Subsequent Unicompartmental Knee Arthroplasty

BACKGROUND

In selected patients, knee arthroscopy is performed prior to unicompartmental knee arthroplasty (UKA) to treat symptomatic mechanical pathology, delay arthroplasty, and assess the knee compartments. The purpose of this study was to determine if knee arthroscopy prior to UKA is associated with increased rates of UKA failure or conversion to total knee arthroplasty (TKA).

METHODS

Data was collected from the Humana insurance database from 2007-2017. Patients who underwent knee arthroscopy within two years prior to UKA were identified and matched with controls based on age, gender, Charlson Comorbidity Index, smoking status, and obesity. Rates of conversion to TKA and failure for various causes were compared between cohorts.

RESULTS

Prior to propensity matching, 8353 UKA patients met inclusion criteria. Of these, 1079 patients (12.9%) underwent knee arthroscopy within two years of UKA and were matched to 1079 patients (controls) who did not undergo knee arthroscopy in the two years preceding UKA. No differences in demographics/comorbidities existed among cohorts. Compared to controls, the knee arthroscopy cohort was more likely to experience failure for aseptic loosening (2.4% vs 1.1%; OR 2.166; P = .044) and significantly more likely to require conversion to TKA (10.4% vs 4.9%; OR 2.113; P < .001) within two years of UKA.

CONCLUSION

Knee arthroscopy within two years of UKA is associated with an increased rate of UKA conversion to TKA and a higher rate of UKA failure from aseptic loosening. Although clinicians should be mindful of this association when performing knee arthroscopy in patients who may be indicated for future UKA, further research is needed to better characterize these findings.

Comparison of Revision Risk Based on Timing of Knee Arthroscopy Prior to Total Knee Arthroplasty

BACKGROUND

Knee arthroscopy may be performed prior to total knee arthroplasty (TKA) in patients with symptomatic degenerative knee changes that do not yet warrant TKA. The purpose of this study was to determine whether the time interval between knee arthroscopy and subsequent primary TKA is associated with increased rates of revision and certain complications following TKA.

METHODS

Data from 2006 to 2017 were collected from a national insurance database. Patients who underwent knee arthroscopy within 1 year prior to primary TKA were identified and stratified into the following cohorts based on stratum-specific likelihood ratio (SSLR) analysis: 0 to 15, 16 to 35, 36 to 43, and 44 to 52 weeks from the time of knee arthroscopy to TKA. Univariate and multivariable analyses were conducted to determine the association between these specific time intervals and rates of revision surgery, periprosthetic joint infection (PJI), aseptic loosening, and manipulation under anesthesia.

RESULTS

In total, 130,128 patients were included in this study; 6,105 (4.7%) of those patients underwent knee arthroscopy within 1 year prior to TKA and 124,023 (95.3%) underwent TKA without any prior knee surgery, including arthroscopy (the control group). Relative to the control group, the likelihood of undergoing revision surgery was significantly greater in patients who underwent knee arthroscopy ≤15 weeks (odds ratio [OR]: 1.79; 95% confidence interval [CI]: 1.43 to 2.22; p < 0.001) or 16 to 35 weeks (OR: 1.20; 95% CI: 1.01 to 1.42; p = 0.035) prior to TKA. Patients were at significantly increased risk for PJI if knee arthroscopy was done ≤35 weeks prior to TKA, and all 4 time groups that underwent knee arthroscopy within 1 year before TKA were at increased risk for manipulation under anesthesia.

CONCLUSIONS

We found a time-dependent relationship between the timing of knee arthroscopy and complications following TKA, with the prevalence of revision surgery and PJI increasing as knee arthroscopy was performed closer to the time of TKA. This study suggests that an interval of at least 36 weeks should be maintained between the 2 procedures to minimize risks of PJI and revision surgery.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Patients undergoing manipulation after total knee arthroplasty are at higher risk of revision within 2 years

BACKGROUND

Total knee arthroplasty (TKA) is a very common orthopedic procedure and stiffness is a common complication following TKA. There is extensive data regarding timing and success of Manipulation under anesthesia (MUA) for stiffness following TKA. However, Studies reporting outcome following MUA have often focused on the improvement in ROM and improvement in functional score with very few studies reporting on the revision risk.

METHODS AND MATERIALS

In this study we retrospectively reviewed PearlDiver insurance database and analyzed the characteristics of the patient undergoing MUA after TKA. We also analyzed the risk of revision at 2 years in a cohort of MUA patients who were matched to patients without MUA.

RESULT

Our study identified 9156 patients who underwent MUA within one year following TKA. MUA was slightly more common in females and risk of manipulation decreases with increasing age. Comparative analysis showed that at two years, patients in the matched MUA cohort (538 patients, 5.99%) were 2.9 times more likely to undergo revision TKA compared to the matched non MUA group (194, 2.16%)OR 2.88 (95% CI-2.44 to 3.41), P < 0.05 CONCLUSION: Retrospective database review showed that the risk of revision is higher in patients undergoing MUA after TKA and hence patient should be counselled about the possibility of revision in the future.

Increasing Prevalence of Anxiety and Depression Disorders After Diagnosis of Chronic Pancreatitis: A 5-Year Population-Based Study

OBJECTIVES

Chronic pancreatitis (CP) is often associated with poor quality of life. Only a few small associative studies have reported the prevalence of mood disorders in CP. Using a large database, we sought to describe the epidemiology and risk association of anxiety and depression in CP and evaluate their outcomes.

METHODS

A multicenter database (Explorys), an aggregate of electronic health record data from 26 US healthcare systems, was surveyed. A cohort of patients with a diagnosis of CP between 2014 and 2019 was identified. Within this cohort, rates of anxiety and depression were calculated. Demographics, comorbidities, and outcomes were described.

RESULTS

Of the 30,276,810 individuals in the database (2014-2019), 67,260 patients had a CP diagnosis (0.22%). When compared with patients with no history of CP, patients with CP were more likely to develop anxiety (odds ratio, 6.94; 95% confidence interval, 6.85-7.04) and depression (odds ratio, 5.09; 95% confidence interval, 5.01-5.17). Chronic pancreatitis patients with depression had an increased risk of suicidal ideation compared with controls.

CONCLUSIONS

Patients with CP are at a higher risk of developing anxiety and depression compared with those without CP, with overall worse outcomes. Clinicians should screen CP patients and make appropriate referral to psychiatry when indicated.

Lysis of Adhesion for Arthrofibrosis After Total Knee Arthroplasty Is Associated With Increased Risk of Subsequent Revision Total Knee Arthroplasty

BACKGROUND

The aim of this study is to determine incidence of lysis of adhesion (LOA) for postoperative arthrofibrosis following primary total knee arthroplasty (TKA), patient factors associated with LOA, and impact of LOA on revision TKA.

METHODS

Patients who underwent primary TKA were identified in the Humana and Medicare databases. Patients who underwent LOA within 1 year after TKA were defined as the "LOA" cohort. Multiple binomial logistic regression analyses were performed to identify patient factors associated with undergoing LOA within 1 year after index TKA, and identify risk factors including LOA on risk for revision TKA within 2 years of index TKA.

RESULTS

In total, 58,538 and 48,336 patients underwent primary TKA in the Medicare and Humana databases, respectively. Incidence of LOA within 1 year after TKA was 0.56% in both databases. Age <75 years was a significant predictor of LOA in both databases (P < .05 for both). Incidence of revision TKA was significantly higher for the "LOA" cohort when compared to the "TKA Only" cohort in both databases (P < .0001 for both). LOA was the strongest predictor of revision TKA within 2 years after index TKA in both databases (P < .0001 for both). Additionally, age <65 years, male gender, obesity, fibromyalgia, smoking, alcohol abuse, and history of anxiety or depression were independently associated with increased odds of revision TKA within 2 years after index TKA (P < .05 for all).

CONCLUSION

Incidence of LOA after primary TKA is low, with younger age being the strongest predictor for requiring LOA. Patients who undergo LOA for arthrofibrosis within 1 year after primary TKA have a substantially high risk for subsequent early revision TKA.

LEVEL OF EVIDENCE

III, Retrospective Cohort Study.

Impact of COVID-19 on clinical outcomes for patients with fractured hip: a multicentre observational cohort study

Aims

There are reports of a marked increase in perioperative mortality in patients admitted to hospital with a fractured hip during the COVID-19 pandemic in the UK, USA, Spain, and Italy. Our study aims to describe the risk of mortality among patients with a fractured neck of femur in England during the early stages of the COVID-19 pandemic.

Methods

We completed a multicentre cohort study across ten hospitals in England. Data were collected from 1 March 2020 to 6 April 2020, during which period the World Health Organization (WHO) declared COVID-19 to be a pandemic. Patients ≥ 60 years of age admitted with hip fracture and a minimum follow-up of 30 days were included for analysis. Primary outcome of interest was mortality at 30 days post-surgery or postadmission in nonoperative patients. Secondary outcomes included length of hospital stay and discharge destination.

Results

In total, 404 patients were included for final analysis with a COVID-19 diagnosis being made in 114 (28.2%) patients. Overall, 30-day mortality stood at 14.4% (n = 58). The COVID-19 cohort experienced a mortality rate of 32.5% (37/114) compared to 7.2% (21/290) in the non-COVID cohort (p < 0.001). In adjusted analysis, 30-day mortality was greatest in patients who were confirmed to have COVID-19 (odds ratio (OR) 5.64, 95% confidence interval (CI) 2.95 to 10.80; p < 0.001) with an adjusted excess risk of 20%, male sex (OR 2.69, 95% CI 1.37 to 5.29; p = 0.004) and in patients with ≥ two comorbidities (OR 4.68, CI 1.5 to 14.61; p = 0.008). Length of stay was also extended in the COVID-19 cohort, on average spending 17.6 days as an inpatient versus 12.04 days in the non-COVID-19 group (p < 0.001).

Conclusion

This study demonstrates that patients who sustain a neck of femur fracture in combination with COVID-19 diagnosis have a significantly higher risk of mortality than would be normally expected.Cite this article: Bone Joint Open 2020;1-11:697-705.

Prior Manipulation under Anesthesia is a Predictor of Contralateral Manipulation in Staged Bilateral Total Knee Arthroplasty

BACKGROUND

There are many risk factors for arthrofibrosis and manipulation under anesthesia (MUA) following total knee arthroplasty (TKA). However, no study has elucidated whether a history of MUA increases the risk of contralateral MUA in patients undergoing staged bilateral TKA.

METHODS

A retrospective review of an institutional database of TKAs was performed. All patients aged ≥18 years who underwent primary staged bilateral TKAs were screened for inclusion. Staged bilateral TKAs were viewed as 2 distinct events based on the temporal order in which they occurred: TKA#1 (occurred first) and TKA#2 (occurred second). Following TKA#1, patients were split into 2 groups: those who underwent MUA (Group MANIP) and those who did not (Group NO MANIP). The subsequent risk of undergoing MUA following TKA#2 was then assessed and compared between the 2 groups. Chi-squared tests were used for comparison.

RESULTS

A total of 5,330 patients who underwent primary uncomplicated staged bilateral TKAs (10,660 knees) during the study period were identified. Overall, 2.1% of patients underwent MUA following TKA#1 and 1.9% of patients underwent MUA following TKA#2. In the MANIP group, 21.4% of patients underwent MUA following TKA#2, while only 1.5% underwent MUA in the NO MANIP group. This 14.3-fold increase in the risk of MUA in the MANIP group following TKA#2 was statistically significant (21.4% vs 1.5%, absolute risk reduction = 19.9%, relative risk reduction = 93.0%, P < .0001).

CONCLUSION

Patients who undergo MUA during the first TKA of a staged bilateral TKA are 14.3 times more likely to undergo a subsequent MUA than those who did not undergo MUA following their first TKA.

The Epidemiology of Pancreatic Cancer and the Association With Acetylsalicylic Acid in the United States: A Population-Based Study

OBJECTIVES

Pancreatic cancer (PaC) is the third leading cause of cancer-related death in the United States. Multiple studies have investigated the epidemiology and the association between PaC and acetylsalicylic acid (ASA) use, revealing mixed results. Using a large database, we sought to investigate the epidemiology of PaC.

METHODS

Using a commercial database (Explorys Inc, Cleveland, Ohio), which includes electronic health record data from 26 major integrated US health care systems, all patients 18 years and older diagnosed with PaC for 5 years were identified based on Systematized Nomenclature Of Medicine-Clinical Terms. We determined the prevalence of PaC and the potential associated factors using univariable and multivariable analysis.

RESULTS

Of the 32,970,850 individuals, we identified 30,250 individuals with PaC with an overall prevalence of 0.08%. Individuals with PaC were more likely to be males, seniors (age, >65 years), and White, compared with patients without PaC. In subgroup analysis of chronic pancreatitis, individuals on ASA, individuals >65 years, White, and White males were less likely to have PaC, and non-White females were more likely to have PaC.

CONCLUSIONS

This is the largest population-based study evaluating the epidemiology of PaC. We observed a protective association of ASA on a subgroup of patients with PaC and chronic pancreatitis.

Manipulation Under Anesthetic After Primary Knee Arthroplasty Is Associated With a Higher Rate of Subsequent Revision Surgery

AIM

To determine the association between manipulation under anesthetic (MUA) after primary knee arthroplasty and subsequent revision surgery.

METHODS

Patients undergoing primary knee arthroplasty from April 2011 to April 2016 with minimum 1-year follow-up to April 2017 were identified from the national hospital episode statistics for England. The first arthroplasty per patient, per side, was included; cases with a record of subsequent infection or periprosthetic fracture were excluded. Patients undergoing MUA within 1 year to the same knee were identified, defining the populations for the MUA and non-MUA cohorts. Mortality-adjusted Kaplan-Meier survival analysis (revision arthroplasty) was performed to a maximum of 6 years. A Cox proportional hazards model was used to determine the hazard for revision, adjusting for type of primary arthroplasty, gender, age group, year, comorbidity index, obesity, regional deprivation, rurality, and ethnicity.

RESULTS

A total of 309,650 primary arthroplasty cases (309,650 patients) were included. MUA within 1 year was recorded in 6882 patients (2.22%; 95% confidence interval [95% CI], 2.17-2.28) defining the MUA cohort; all others were included in the parallel non-MUA cohort. At 6 years, the mortality-adjusted estimated implant survival rate in the MUA cohort was 91.2% (95% CI, 90.0-92.2) in comparison to 98.1% (95% CI, 98.0-98.2) in the non-MUA cohort. In the fully adjusted model, this corresponded to an adjusted hazard for revision of 5.03 (hazard ratio; 95% CI, 4.55-5.57).

CONCLUSION

Patients who underwent MUA within 1 year of primary arthroplasty were at a 5-fold increased risk of subsequent revision even after excluding cases of infection or fracture. Further investigation of the etiology of stiffness after primary knee arthroplasty and the optimal treatment options to improve outcomes is justified.

Manipulation under anesthesia as a therapy option for postoperative knee stiffness: a retrospective matched-pair analysis

INTRODUCTION

Due to demographic changes, total knee arthroplasty (TKA) is one of the most frequently performed orthopedic surgeries. Therapies for associated postoperative complications, such as postoperative knee stiffness (PKS), are becoming increasingly important. The aim of this retrospective matched-pair analysis was to evaluate mid-term-results following manipulation under anesthesia (MUA).

MATERIALS AND METHODS

Fifty-one patients with PKS were evaluated and 51 matched-pair patients without PKS after primary TKA were chosen for the control group. In addition to the range of motion, the functionality was recorded by Knee Society Score (KSS), Western Ontario and Mc Masters Universities Osteoarthritis Index (WOMAC), and Short-Form-12 Questionnaire (SF-12). Experience of pain was mapped using a 10-point Numeric Rating Scale (NRS), and the analgesic requirement was mapped using the WHO step scheme. A final follow-up examination was conducted approximately three years after TKA. To evaluate potential risk factors for the development of PKS, TKA alignment was measured via postoperative X-ray images.

RESULTS

Improvement of the average knee flexion of 35.7° and total flexion of 107.4° was detected in PKS patients after MUA. The flexion of the control group was 112.4°; no significant between-group difference was present regarding prosthesis type, sex, age and BMI. Regarding KSS, WOMAC, and SF-12, the MUA cohort achieved statistically-relevant lower overall scores than the control group, p = 0.006, p = 0.005, p = 0.001, respectively. Significantly higher experiences of pain and a higher need for analgesics in MUA patients were reported (p = 0.001 and p < 0.001, respectively). Radiological evaluation of the prosthesis alignment did not show any differences between the two groups.

CONCLUSIONS

MUA can improve mobility after PKS, whereby MUA seemed to be a functional therapy option for PKS. Compared to the control group, the MUA group showed lower functional values and an increased experience of pain. A correlation between prosthesis malalignment and MUA could not be detected radiologically. Further studies are necessary to investigate the reasons for PKS.

The Association of Race/Ethnicity and Total Knee Arthroplasty Outcomes in a Universally Insured Population

BACKGROUND

Prior studies have documented racial/ethnic disparities in the United States for total knee arthroplasty (TKA) outcomes. One factor cited as a potential mediator is unequal access to care. We sought to assess whether racial/ethnic disparities persist in a universally insured TKA population.

METHODS

A US integrated health system's total joint replacement registry was used to identify elective primary TKA (2000-2016). Racial/ethnic differences in revision and 90-day postoperative events (readmission, emergency department [ED] visit, infection, venous thromboembolism, and mortality) were analyzed using Cox proportional hazard and logistic regression with adjustment for confounders.

RESULTS

Of 129,402 TKA, 68.8% were white, 16.2% were Hispanic, 8.4% were black, and 6.6% were Asian. Compared to white patients, Hispanic patients had lower risks of septic revision (hazard ratio [HR] = 0.69, 95% confidence interval [CI] = 0.57-0.83) and infection (odds ratio [OR] = 0.42, 95% CI = 0.30-0.59), but a higher likelihood of ED visit (OR = 1.28, 95% CI = 1.22-1.34). Black patients had higher risks of aseptic revision (HR = 1.61, 95% CI = 1.42-1.83), readmission (OR = 1.13, 95% CI = 1.02-1.24), and ED visit (OR = 1.31, 95% CI = 1.23-1.39). Asian patients had lower risks of aseptic revision (HR = 0.67, 95% CI = 0.54-0.83), septic revision (HR = 0.78, 95% CI = 0.60-0.99), readmission (OR = 0.89, 95% CI = 0.79-1.00), and venous thromboembolism (OR = 0.59, 95% CI = 0.45-0.78).

CONCLUSION

We observed differences in TKA outcome, even within a universally insured population. While lower risks in some outcomes were observed for Asian and Hispanic patients, the higher risks of aseptic revision and readmission for black patients and ED visit for black and Hispanic patients warrant further research to determine reasons for these findings to mitigate disparities.

LEVEL OF EVIDENCE

Level III.

Racial/Ethnic Disparities in Physical Function Before and After Total Knee Arthroplasty Among Women in the United States

IMPORTANCE

Although racial/ethnic differences in functional outcomes after total knee arthroplasty (TKA) exist, whether such differences are associated with differences in presurgical physical function (PF) has not been thoroughly investigated.

OBJECTIVE

To examine trajectories of PF by race/ethnicity before and after TKA among older women.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted among the prospective Women's Health Initiative with linked Medicare claims data. A total of 10 325 community-dwelling women throughout the United States with Medicare fee-for-service underwent primary TKA between October 1, 1993, and December 31, 2014, and were followed up through March 31, 2017.

EXPOSURES

Race/ethnicity comparisons between Hispanic or Latina women, non-Hispanic black or African American women, and non-Hispanic white women (hereafter referred to as Hispanic, black, and white women, respectively).

MAIN OUTCOMES AND MEASURES

Physical functioning scale scores and self-reported activity limitations with walking 1 block, walking several blocks, and climbing 1 flight of stairs were measured by the RAND 36-Item Health Survey during the decade before and after TKA, with a median of 9 PF measurements collected per participant over time.

RESULTS

In total, 9528 white women (mean [SD] age at surgery, 74.6 [5.5] years), 622 black women (mean [SD] age at surgery, 73.1 [5.3] years), and 175 Hispanic women (mean [SD] age at surgery, 73.1 [5.2] years) underwent TKA. During the decade prior to TKA, black women had lower PF scores than white women (mean difference, -5.8 [95% CI, -8.0 to -3.6]) and higher odds of experiencing difficulty walking a single block (5 years before TKA: odds ratio, 1.86 [95% CI, 1.57-2.21]), walking multiple blocks (odds ratio, 2.14 [95% CI, 1.83-2.50]), and climbing 1 flight of stairs (odds ratio, 1.81 [95% CI, 1.55-2.12]). After TKA, black women continued to have lower PF scores throughout the decade (mean difference 1 year after TKA, -7.8 [95% CI, -10.8 to -4.9]). After adjusting for preoperative PF scores, PF scores after TKA were attenuated (mean difference 1 year after TKA, -3.0 [95% CI, -5.3 to -0.7]), with no statistically significant differences in long-term follow-up. Hispanic women had similar PF scores to white women during the pre-TKA and post-TKA periods.

CONCLUSIONS AND RELEVANCE

This study suggests that black women had significantly poorer PF than white women during the decades before and after TKA. Poorer PF after surgery was associated with poorer preoperative PF. Reducing disparities in post-TKA functional outcomes should target maintenance of function preoperatively in the early stages of arthritic disease and/or reduction of delays to receiving TKA once need arises.

The Risk of Vitamin D Deficiency, Osteoporosis, and Fractures in Acute Pancreatitis

OBJECTIVES

A few past studies have found increased utilization of 25-hydroxyvitamin D and prevalence of osteoporosis in acute pancreatitis (AP). Our aim was to obtain a survey of bone diseases after a sentinel episode of AP.

METHODS

A database (Explorys), an aggregate of electronic health record from 26 integrated United States healthcare systems, was queried. A cohort of patients with a Systematized Nomenclature of Medicine-Clinical Terms diagnosis of AP between 2014 and 2019, after excluding patients with selected medical conditions and medications that are associated with poor bone health, was identified. The prevalence of new diagnoses of vitamin D deficiency (VDD), osteoporosis, and fractures in the study cohort was evaluated. Age-, race-, and sex-based distributions and risk factors were determined through univariate and multivariate analyses.

RESULTS

Of the 36,087,380 individuals in the database, we identified 256,580 (0.71%) with AP. In multivariate analysis, patients with AP were more likely to develop VDD (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.24-1.26; P < 0.0001), osteoporosis (OR, 1.89; CI, 1.81-1.85; P < 0.0001), and fractures (OR, 1.58; 95% CI, 1.57-1.59; P < 0.0001).

CONCLUSIONS

Acute pancreatitis was associated with increased risk of VDD, osteoporosis, and fractures.

Diabetes mellitus does not increase the risk of knee stiffness after total knee arthroplasty: a meta-analysis of 7 studies including 246 053 cases

Purpose

Methods

Results

Conclusion

Level of evidence

Same-Day Surgery Does Not Increase the Manipulation Under Anesthesia and Reoperation Rates for Stiffness Following Bilateral Total Knee Arthroplasty

BACKGROUND

There is a paucity of data on the incidence of stiffness and need for subsequent manipulation under anesthesia (MUA) and reoperation following same-day bilateral total knee arthroplasty (BTKA). We compared the rates of at least 1 MUA, bilateral knee involvement, single and multiple MUA rates, and stiffness-related reoperation rates between patients undergoing same-day, same-admission staged, and staged within 1 year BTKA in a tertiary institution.

METHODS

We analyzed institutional data for 3175 same-day (group A), 153 same-admission staged (group B), and 1226 staged within 1 year BTKA patients (group C) from 1998 to 2009. Several variables, including patient demographics, comorbidity profile, Charlson-Deyo index, and range of motion at different time points, were tabulated. Follow-up was minimum 1 year after first MUA. Univariate analyses were performed using the Wilcoxon rank-sum or Kruskal-Wallis test, and Fisher exact or the chi-square test for continuous and categorical variables, respectively. The Cochran-Armitage trend test was used to check the bilateral knee involvement rate across groups.

RESULTS

Overall, 2.2% (98/4554) of BTKA patients required MUA. The rate of at least 1 MUA was similar across groups but the percentage of bilateral knee involvement was higher in group A. The single MUA rate was comparable among groups. Both no revision and revision reoperation rates were similar among the manipulated groups.

CONCLUSION

Same-day BTKA was not associated with increased incidence of single or multiple MUA and stiffness-related reoperation rates. These findings may facilitate preoperative counseling in patients with symptomatic bilateral knee disease, eligible for same-day BTKA.

Manipulation under anesthesia after primary knee arthroplasty in Sweden: incidence, patient characteristics and risk of revision

Background and purpose - The incidence of manipulation under anesthesia (MUA) after knee arthroplasty surgery has been reported to vary between 0.5% and 10%. We evaluated the incidence of MUA after primary knee arthroplasty in Sweden, the demographics of the patients and the risk of revision. Patients and methods - Between 2009 and 2013, 64,840 primary total and unicompartmental knee arthroplasties (TKA and UKA) were registered in the Swedish Knee Arthroplasty Register (SKAR). MUAs performed between 2009 and 2014 were identified through the in- and outpatient registers of the Swedish National Board of Health and Welfare. Pertinent data were verified through medical records and patient demographics and revisions were obtained from the SKAR. Results - 1,258 MUAs were identified. Of these, 1,078 were 1st-time MUAs, performed within 1 year after the primary knee arthroplasty. The incidence of MUA was 1.7% and the incidence varied between hospitals from 0% to 5%. The majority were performed after TKA (98%), in younger patients (65% < 65 years), women (64%), and relatively healthy persons (88% had ASA ≤ 2). The cumulative risk of revision at 10 years was 10% (95% CI 8.6-12), similar for men and women. Interpretation - In Sweden, MUA is a rather uncommon measure after knee arthroplasty, especially after UKA. The CRR at 10 years was doubled compared to the general knee arthroplasty population. The frequency of the procedure varies between hospitals but in general it is performed more frequently in healthier and younger patients.

Younger age is associated with increased odds of manipulation under anesthesia for joint stiffness after total knee arthroplasty

INTRODUCTION

Limited range of motion (ROM) after total knee replacement (TKR) is associated with low function and might require manipulation under anaesthesia (MUA). In order to identify factors associated with a limited ROM we investigated predictors for MUA. We hypothesized that older age was associated with higher MUA due to limited ROM post TKR.

METHODS

In a case control study we investigated all patients undergoing primary TKR at a University Hospital in Sweden between 2007-2012. We registered background factors and compared those between the group who underwent MUA and those who did not. Odds ratios (OR) were calculated in a univariate analysis and an adjusted regression analysis.

RESULTS

Of the total of 669 TKRs performed, 31 patients who had undergone MUA were identified. The prevalence of MUA was 4.6%. The mean increase in ROM after MUA was 27 degrees at final minimum one-year follow-up. After controlling for confounders, patients with good health and young age had increased OR for MUA. OR decreased 0.93 (CI 0.93-0.97) per increased age year in the multiple regression analysis. Diabetes mellitus, BMI and sex did not have a significant effect on the odds ratio for MUA.

DISCUSSION

Young patients undergoing TKR has earlier been identified as a group with a higher grade of dissatisfaction and complications. We found an association between young age and MUA after TKR indicating an additional, rather unknown complication for this group of patients. The background and reasons for this has to be further investigated.

LEVEL OF EVIDENCE

II, cohort study/case control study (case control is level III).

Self-Directed Home Exercises vs Outpatient Physical Therapy After Total Knee Arthroplasty: Value and Outcomes Following a Protocol Change

BACKGROUND

The need for outpatient physical therapy (OPPT) has been questioned following primary total knee arthroplasty (TKA). Recent studies have suggested that similar outcomes may be possible with self-directed home exercise programs (HEP) compared to OPPT, which can be costly to both the patient and healthcare system. The aim of the present study is to compare the safety, efficacy, and health economics of formal OPPT with self-directed home exercises after TKA following a protocol change.

METHODS

A single-surgeon, retrospective study of 520 consecutive patients undergoing primary unilateral TKA from 2016 to 2018 was performed. All 251 TKAs performed in 2016 were routinely prescribed OPPT, while all 269 TKAs in 2017 completed a self-directed HEP alone for 2 weeks. At their 2-week visit, OPPT was prescribed if patients had less than 90° range of motion or per patient request. Financial data of postdischarge costs were collected for all patients. Multivariate logistic regression evaluated for variables associated with failure of the HEP program.

RESULTS

Overall, 65.8% (177/269) of patients in the HEP group did not require OPPT. There was no significant difference in percentage of patients whose range of motion was less than 90° at 2-week follow-up between OPPT and HEP (14% vs 11.9%, P = .467). Between OPPT and HEP, there were no differences in manipulation under anesthesia (3.2% vs 3%, P = .883). On average, patients who received OPPT incurred an increase in average cost of $1340.87 and $1893.42 for Medicare and private insurer patients, respectively. We did not identify any significant risk factors for failing HEP.

CONCLUSION

Comparable outcomes were demonstrated between patients receiving HEP compared to OPPT with a substantial cost saving. While a portion of patients still require formal OPPT, the majority do not. Surgeons should consider an initial trial of HEP with close follow-up in order to limit unnecessary costs associated with OPPT.

Prediction of the need for manipulation under anesthesia for flexion contracture after total knee arthroplasty in patients of advanced age

Objective

This study was performed to develop a prediction model for requiring manipulation under anesthesia (MUA) for flexion contracture after total knee arthroplasty (TKA) in patients of advanced age.

Methods

We retrospectively reviewed 269 patients of advanced age undergoing primary TKA in one center with a minimum 1-year follow-up. Patients who underwent postoperative MUA had flexion contracture of >10° after 4 weeks of postoperative rehabilitation, and their demographic data and preoperative clinical conditions [knee diagnosis, diabetes mellitus, hypertension, lumbar spinal disorders, hip disorders, ankle disorders, knee deformity (varus/valgus), preoperative flexion contracture (PFC), range of motion (ROM), and Hospital for Special Surgery (HSS) knee score] were compared with those of patients without MUA. All preoperative factors were collected to develop the predictive model.

Results

Thirty patients underwent MUA. Patients who underwent MUA after surgery had significant differences in PFC, higher HSS knee scores before surgery (59.10 ± 7.22 vs. 55.70 ± 13.09), and lower preoperative ROM (81.57 ± 30.86 vs. 95.47 ± 24.36) than those who did not undergo MUA.

Conclusion

A prediction model for MUA in advanced-age patients with flexion contracture was developed and mainly consisted of preoperative risk factors including PFC, HSS scores, and ROM.

Differences in Perioperative Outcomes and Complications Between African American and White Patients After Total Joint Arthroplasty

BACKGROUND

Racial disparities in healthcare utilization and outcomes have been reported and have wide-reaching implications for individual patient and healthcare system; as providers we bear an ethical burden to address this disparity and provide culturally competent care. This study will examine the influence of race on length of stay, discharge disposition, and complications requiring reoperation following total joint arthroplasty (TJA).

METHODS

Single institution retrospective analysis of a consecutive series of 7208 primary TJA procedures performed between July 2013 and June 2017 was conducted. Chi-squared and t-tests were used to quantify differences between the groups and multiple logistic regression was used to identify race as an independent risk factor.

RESULTS

In total, 6182 (84.3%) white and 1026 (14.0%) African American (AA) patients were included. AA patients were younger (63.62 vs 66.84 years, P < .001), more likely female (68.8% vs 57.0%, P < .001), had a longer length of stay (2.19 vs 2.00 days, P < .001), more likely to experience septic complications (1.3% vs 0.5%, P = .002) and manipulation under anesthesia (3.9% vs 1.8%, P < .001), and less likely to discharge home (67.1% vs 81.1%, P < .001). Multiple logistic regression showed that AA patients were more likely to discharge to a facility (adjusted odds ratio 2.63, 95% confidence interval 2.19-3.16, P < .001) and experience a manipulation under anesthesia (adjusted odds ratio 1.90, 95% confidence interval 1.26-2.85, P = .002).

CONCLUSION

AA patients undergoing TJA were younger with longer length of stay and a higher rate of nonhome discharge; AA race was identified as an independent risk factor. Further study is required to understand the differences identified in this study. Targeted interventions should be developed to attempt to eliminate the disparity.

Patient-related Risk Factors for Postoperative Stiffness Requiring Surgical Intervention After Arthroscopic Rotator Cuff Repair

INTRODUCTION

Risk factors for stiffness after arthroscopic rotator cuff repair (RCR) have been limited to studies with small patient numbers. The objective is to determine patient-related risk factors for stiffness after RCR.

METHODS

The PearlDiver database was queried from 2007 to 2015 for patients undergoing isolated arthroscopic RCR. A multivariate binomial logistic regression analysis assessed for risk factors requiring a postoperative manipulation under anesthesia (MUA) or lysis of adhesions (LOA) within 9 months after RCR.

RESULTS

Two hundred thirty-two of 19,229 patients (1.2%) underwent a LOA and/or MUA within 9 months after arthroscopic RCR. Significant risk factors identified were age less than 50 years (odds ratio [OR], 1.9; P < 0.0001), female gender (OR, 2.0; P < 0.0001), diabetes mellitus (DM) type I (OR, 2.7; P < 0.0001), hypothyroidism (OR, 1.3; P = 0.020), and systemic lupus erythematosus (OR, 2.1; P = 0.004). However, tobacco use was associated with a 0.5 risk of developing stiffness (P < 0.0001).

DISCUSSION

Systemic lupus erythematosus, hypothyroidism, and DMI (but not DMII) in addition to young age and female gender were risk factors for LOA/MUA after arthroscopic RCR.

Can We Avoid Implant-selection Errors in Total Joint Arthroplasty?

BACKGROUND

Implant selection in the operating room is a manual process. This manual process combined with complex compatibility rules and inconsistent implant labeling may lead to implant-selection errors. These might be reduced using an automated process; however, little is known about the efficacy of available automated error-reduction systems in the operating room.

QUESTIONS/PURPOSES

(1) How often do implant-selection errors occur at a high-volume institution? (2) What types of implant-selection errors are most common?

METHODS

We retrospectively evaluated our implant log database of 22,847 primary THAs and TKAs to identify selection errors. There were 10,689 THAs and 12,167 TKAs included during the study period from 2012 to 2017; there were no exclusions and we had no missing data in this study. The system provided an output of errors identified, and these errors were then manually confirmed by reviewing implant logs for each case found in the medical records. Only those errors that were identified by the system were manually confirmed. During this time period all errors for all procedures were captured and presented as a proportion. Errors identified by the software were manually confirmed. We then categorized each mismatch to further delineate the nature of these events.

RESULTS

One hundred sixty-nine errors were identified by the software system just before implantation, representing 0.74 of the 22,847 procedures performed. In 15 procedures, the wrong side was selected. Twenty-five procedures had a femoral head selected that did not match the acetabular liner. In one procedure, the femoral head taper differed from the femoral stem taper. There were 46 procedures in which there was a size mismatch between the acetabular shell and the liner. The most common error in TKA that occurred in 46 procedures was a mismatch between the tibia polyethylene insert and the tibial tray. There were 13 procedures in which the tibial insert was not matched to the femoral component according to the manufacturer's guidelines. Selection errors were identified before implantation in all procedures.

CONCLUSIONS

Despite an automated verification process, 0.74% of the arthroplasties performed had an implant-selection error that was identified by the software verification. The prevalence of incorrect/mismatched hip and knee prostheses is unknown but almost certainly underreported. Future studies should investigate the prevalence of these errors in a multicenter evaluation with varying volumes across the involved sites. Based on our results, institutions and management should consider an automated verification process rather than a manual process to help decrease implant-selection errors in the operating room.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Manipulation under anesthesia following total knee arthroplasty: a comprehensive review of literature

INTRODUCTION

The etiology of the stiff knee after total knee arthroplasty (TKA) is largely unknown, although excessive scar tissue due to arthrofibrosis is an important reason for a limited range of motion (ROM) after this procedure. Persistent limited ROM after TKA results in poor patient-reported outcomes and is increasingly becoming a more prominent reason for TKA revision surgery.

METHODS

A narrative review of current literature on manipulation under anesthesia (MUA) after TKA analyzing etiology and risk factors for stiffness after TKA, effectiveness of MUA and what is known about rehabilitation after MUA.

RESULTS

Literature describes numerous risk factors for insufficient knee ROM after TKA, but a comprehensive valid risk model is lacking. MUA is an effective treatment option with evidence suggesting better outcomes if performed within the first 3 months after TKA. The wide variety in both the indication and timing for MUA, and the lack of scientific evidence on how to rehabilitate patients after MUA, complicates the interpretation of available literature. This is even more so the case on the reporting of one versus two or more MUAs after TKA.

CONCLUSION

Future comparative trials, preferably with a randomized study design, should be conducted to elude more clear indications for MUA, to give clinical guidance on correct timing for MUA and on how to rehabilitate patients afterward.

Elevated Venous Thromboembolism Risk Following Colectomy for IBD Is Equal to Those for Colorectal Cancer for Ninety Days After Surgery

BACKGROUND

The risk of postoperative venous thromboembolism is high in patients with colon cancer and IBD. Although The American Society of Colon and Rectal Surgeons suggests posthospital prophylaxis after surgery in patients with colon cancer, there are no such recommendations for patients with IBD.

OBJECTIVE

This study aims to analyze the incidence and risk factors for postoperative venous thromboembolism.

DESIGN

This was a retrospective review using the Explorys platform.

SETTINGS

Aggregated electronic medical records from 26 major health care systems across the United States from 1999 to 2017 were used for this study.

PATIENTS

Patients who underwent colon surgery were included.

MAIN OUTCOME MEASURES

Patients were followed up to 90 days postoperatively for deep vein thrombosis and pulmonary embolism.

RESULTS

A total of 75,620 patients underwent colon resections, including 32,020 patients with colon cancer, 9850 patients with IBD, and 33,750 patients with diverticulitis. The 30-day incidence of venous thromboembolism was higher in patients with cancer and IBD than in patients with diverticulitis (2.9%, 3.1%, and 2.4%, p < 0.001 for both comparisons). The 30-day incidence of venous thromboembolism in patients with ulcerative colitis is greater than in patients with Crohn's disease (4.1% vs 2.1%, p < 0.001). The cumulative incidence of venous thromboembolism increased from 1.2% at 7 days after surgery to 4.3% at 90 days after surgery in patients with cancer, and from 1.3% to 4.3% in patients with IBD. In multivariable analysis, increase in the risk of venous thromboembolism was associated with cancer diagnosis, IBD diagnosis, age ≥60, smoking, and obesity.

LIMITATIONS

This study was limited by its retrospective nature and by the use of the aggregated electronic database, which is based on charted codes and contains only limited collateral clinical data.

CONCLUSIONS

Because of the elevated and sustained risk of postoperative thromboembolism, patients with IBD, especially ulcerative colitis, might benefit from extended thromboembolism prophylaxis similar to that of patients with colon cancer. See Video Abstract at http://links.lww.com/DCR/A544.