Risk Factors for Short-term Complications of Anterior Cruciate Ligament Reconstruction in the United States

Characteristics of early complications in isolated primary anterior cruciate ligament reconstruction surgery

PURPOSE

The early complications of isolated anterior cruciate ligament reconstruction surgery (ACLR) have not been well characterized using large databases. This study aims to characterize incidence, impact, and risk factors for short-term operative complications following elective, isolated ACLR surgery. We hypothesize that demographic and perioperative factors may predict 30-day complications after isolated ACLR.

METHODS

This case-control analysis of the American College of Surgeons National Surgical Quality Improvement Program Database (2005-2017) used Current Procedural Terminology codes to identify elective, isolated ACLR patients. Patients undergoing concomitant procedures were excluded. Complications were analyzed using bivariate analysis against demographic variables. Multiple stepwise logistic regression was used to identify independent risk factors for morbidity after ACLR.

RESULTS

A total 12,790 patients (37.0% female, p = 0.674) were included with a mean age of 32.2 years old (SD 10.7 years, p < 0.001). Mean BMI was 27.8 kg/m2 (6.5) where 28.9% of patients had a BMI > 30 (p = 0.064). The most common complications were wound-related (0.57%). In cases with complications, there were higher rates of (1.3% vs 0.8%, p = 0.004) prolonged operation (> 1.5 h), higher rate (2.9% vs 1.8%, p = 0.004) of extended length of stay (≥ 1 day), unplanned reoperation (15.8% vs 0.3%, p < 0.001), and unplanned readmission (17.5% vs 0.3%, p < 0.001). Multivariate analysis showed prolonged operative time (p = 0.001), dyspnea (p = 0.008), and non-ambulatory surgery (p = 0.034) to be predictive of any complication. Dependent functional status (p = 0.091), mFI-5 > 0.2 (= 0.173), female sex (p = 0.191), obesity (p = 0.101), and smoking (p = 0.113) were not risk factors for complications.

CONCLUSION

ACLR is associated with low rates of morbidity and readmissions. The most common comorbidities, complications, and predictors of morbidities were identified to aid surgeons in further reducing adverse outcomes of ACLR. Operative time > 1.5 h, dyspnea, and non-ambulatory surgery are predictive of complications.

Factors associated with increased 30-day re-operation risk in anterior cruciate ligament reconstruction

BACKGROUND

Revision surgery following isolated anterior cruciate ligament reconstruction (ACLR) has often focused on mid- to long-term revisions due to re-rupture, while short-term 30-day revision is a rare, but underappreciated entity. This study aims to characterize incidence and risk factors for reoperations following isolated ACLR.

METHODS

This is a retrospective case-control analysis of the American College of Surgeons National Surgical Quality Improvement Program Database (NSQIP) database from 2005 to 2017. Current Procedural Terminology codes were used to identify elective isolated ACLR patients. Patients undergoing reoperations were analyzed using bivariate analysis against their respective perioperative variables. Multivariate stepwise logistic regression was used to identify independent risk factors for reoperations after ACLR.

RESULTS

12,790 patients were included in the study. 37.0% of patients were female. Mean age was 32.2+/-10.7 years and mean body mass index (BMI) was 27.8+/-6.5 kg/m2, with 28.9% of patients with BMI > 30. The most frequently reported reason for reoperation based on CPT and ICD-9/10 codes was postoperative infection (0.5%). Overall reoperation rate was approximately 0.5%. Multivariate analysis identified operative time >1.5 h (OR 2.6 [95% CI; 1.5-4.4]), dependent functional status (OR 14.0 [1.4-141.6]), and adjunctive anesthesia (OR 2.4 [95% CI; 1.1-5.0]) as independent risk factors for reoperation. Female sex was a protective factor against reoperations (OR 0.6 [0.3-0.98]).

CONCLUSION

Primary, isolated ACLR is associated with extremely low rates of short-term reoperations. Operative time >1.5 h, dependent functional status, and adjunctive anesthesia were independent risk factors for reoperation and female sex was a protective factor against reoperation.

LEVEL OF EVIDENCE

Level III. Retrospective cohort study.

Comparison of surgical or non-surgical management for non-acute anterior cruciate ligament injury: the ACL SNNAP RCT

Background

Anterior cruciate ligament injury of the knee is common and leads to decreased activity and risk of secondary osteoarthritis of the knee. Management of patients with a non-acute anterior cruciate ligament injury can be non-surgical (rehabilitation) or surgical (reconstruction). However, insufficient evidence exists to guide treatment.

Objective(s)

To determine in patients with non-acute anterior cruciate ligament injury and symptoms of instability whether a strategy of surgical management (reconstruction) without prior rehabilitation was more clinically and cost-effective than non-surgical management (rehabilitation).

Design

A pragmatic, multicentre, superiority, randomised controlled trial with two-arm parallel groups and 1:1 allocation. Due to the nature of the interventions, no blinding could be carried out.

Setting

Twenty-nine NHS orthopaedic units in the United Kingdom.

Participants

Participants with a symptomatic (instability) non-acute anterior cruciate ligament-injured knee.

Interventions

Patients in the surgical management arm underwent surgical anterior cruciate ligament reconstruction as soon as possible and without any further rehabilitation. Patients in the rehabilitation arm attended physiotherapy sessions and only were listed for reconstructive surgery on continued instability following rehabilitation. Surgery following initial rehabilitation was an expected outcome for many patients and within protocol.

Main outcome measures

The primary outcome was the Knee Injury and Osteoarthritis Outcome Score 4 at 18 months post randomisation. Secondary outcomes included return to sport/activity, intervention-related complications, patient satisfaction, expectations of activity, generic health quality of life, knee-specific quality of life and resource usage.

Results

Three hundred and sixteen participants were recruited between February 2017 and April 2020 with 156 randomised to surgical management and 160 to rehabilitation. Forty-one per cent (n = 65) of those allocated to rehabilitation underwent subsequent reconstruction within 18 months with 38% (n = 61) completing rehabilitation and not undergoing surgery. Seventy-two per cent (n = 113) of those allocated to surgery underwent reconstruction within 18 months. Follow-up at the primary outcome time point was 78% (n = 248; surgical, n = 128; rehabilitation, n = 120). Both groups improved over time. Adjusted mean Knee Injury and Osteoarthritis Outcome Score 4 scores at 18 months had increased to 73.0 in the surgical arm and to 64.6 in the rehabilitation arm. The adjusted mean difference was 7.9 (95% confidence interval 2.5 to 13.2; p = 0.005) in favour of surgical management. The per-protocol analyses supported the intention-to-treat results, with all treatment effects favouring surgical management at a level reaching statistical significance. There was a significant difference in Tegner Activity Score at 18 months. Sixty-eight per cent (n = 65) of surgery patients did not reach their expected activity level compared to 73% (n = 63) in the rehabilitation arm. There were no differences between groups in surgical complications (n = 1 surgery, n = 2 rehab) or clinical events (n = 11 surgery, n = 12 rehab). Of surgery patients, 82.9% were satisfied compared to 68.1% of rehabilitation patients. Health economic analysis found that surgical management led to improved health-related quality of life compared to non-surgical management (0.052 quality-adjusted life-years, p = 0.177), but with higher NHS healthcare costs (£1107, p < 0.001). The incremental cost-effectiveness ratio for the surgical management programme versus rehabilitation was £19,346 per quality-adjusted life-year gained. Using £20,000-30,000 per quality-adjusted life-year thresholds, surgical management is cost-effective in the UK setting with a probability of being the most cost-effective option at 51% and 72%, respectively.

Limitations

Not all surgical patients underwent reconstruction, but this did not affect trial interpretation. The adherence to physiotherapy was patchy, but the trial was designed as pragmatic.

Conclusions

Surgical management (reconstruction) for non-acute anterior cruciate ligament-injured patients was superior to non-surgical management (rehabilitation). Although physiotherapy can still provide benefit, later-presenting non-acute anterior cruciate ligament-injured patients benefit more from surgical reconstruction without delaying for a prior period of rehabilitation.

Future work

Confirmatory studies and those to explore the influence of fidelity and compliance will be useful.

Trial registration

This trial is registered as Current Controlled Trials ISRCTN10110685; ClinicalTrials.gov Identifier: NCT02980367.

Funding

This award was funded by the National Institute of Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 14/140/63) and is published in full in Health Technology Assessment; Vol. 28, No. 27. See the NIHR Funding and Awards website for further award information.

Incidence, Common Pathogens, and Risk Factors for Infection after Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review

We sought to assess the current literature to present a comprehensive summary of the incidence, common pathogens, and risk factors for infection after anterior cruciate ligament (ACL) reconstruction. PubMed, CINAHL, EMBASE, and Scopus databases were searched for relevant studies reporting on infection after ACL reconstruction. Two reviewers independently screened the extracted studies for adherence to inclusion and exclusion criteria. Studies were selected if they reported on the incidence of infection, pathogens cultured from infected knees, or risk factors for infection after primary ACL reconstruction. Exclusion criteria consisted of studies with fewer than 100 patients or studies that included revision ACL reconstruction. Fifty studies met the inclusion and exclusion criteria, reporting on a total of 316,214 ACL reconstructions. Included studies evaluated between 123 and 104,255 patients. The overall incidence of infection was 0.60% (0.15-2.44%). The most common pathogens were Staphylococcus aureus, S. epidermidis, and coagulase-negative Staphylococci. Five studies reported that the use of hamstring autograft was a statistically significant risk factor for infection after ACL reconstruction, thus making hamstring autograft the most commonly reported risk factor. Other reported risk factors included male sex, use of immuno-suppressive medications or intraarticular steroid injections, prior knee surgery, and diabetes. Systematic review of the literature revealed that infection after ACL reconstruction remains an infrequent event with an incidence of 0.60% (0.15-2.44%). Furthermore, the most common pathogens are from the Staphylococcus genus of bacteria, comprising 84% of all culture-positive infections. Multiple risk factors have been reported for ACL reconstruction; however, statistical significance varied across studies. Together, these findings may help guide physicians in the prevention and treatment of infection after ACL reconstruction.

Anterior Cruciate Ligament Reconstruction in Patients Over 40 Years Old Shows Low Failure Rates: A Systematic Review

Purpose

To review the literature reporting on complications and failure rates after primary anterior cruciate ligament reconstruction (ACLR) in patients ≥40 years.

Methods

This was a secondary analysis from a prior systematic review of the MEDLINE, CINAHL, SportDiscus, Embase, Web of Science, and Cochrane databases on studies evaluating clinical outcomes in ACLR patients ≥40 years. Studies were included based on the following criteria: English-language studies reporting on postoperative complications and/or ACLR failure rates in patients ≥40 years. Case reports, technical notes, studies with duplicate reporting of patient cohorts, or studies using publicly available registry data were excluded. ACLR failure definitions, failure rates, graft rupture rates, revision ACLR and non-ACLR revision rates, and complication rates were recorded.

Results

Twenty-one studies were included following full-text review. Autografts were used in 89.0% of cases. Definitions for ACLR failure varied, ranging from (1) revision ACLR, (2) graft rupture, (3) clinical examination of increased knee laxity, and (4) postoperative arthrofibrosis requiring an additional surgery. The median ACLR failure rate was 5.0% (range, 0%-12.1%) among the 9 studies reporting this outcome, with only 4 of the studies providing explicit definitions of failure. The median ACLR revision surgery, graft rupture, and non-ACLR revision surgery rates were 0% (range, 0%-7.7%), 2.7% (range, 0%-9.1%), and 7.2% (range 0%-34.4%), respectively. Commonly reported complications included pain (range, 0%-14.0%), stiffness (range, 0%-12.7%), hematoma (range, 2.5%-8.8%), neurovascular (range, 0%-41.7%), and undefined (range, 0%-13.8%).

Conclusions

ACLR in patients over 40 years old shows low failure rates.

Level of Evidence

Level IV, systematic review of Level II-IV studies.

Graft failure within 2 years of isolated anterior cruciate ligament reconstruction is associated with increased risk of secondary meniscus tears

PURPOSE

A debilitating complication following anterior cruciate ligament reconstruction is a secondary meniscus tear. Currently, the literature is mixed regarding the risk factors associated with the incidence of secondary meniscus tears. The aim of this study was to investigate risk factors associated with meniscus tears following an isolated primary anterior cruciate ligament reconstruction. ACL graft failure was hypothesized to be the strongest risk factor for secondary meniscal injury occurrence.

METHODS

A retrospective cohort analysis was performed using the PearlDiver Database. Patients with a primary anterior cruciate ligament reconstruction were identified in the database. Patients with concomitant knee ligament injury or meniscus injury present at the time the index procedure were excluded. Patients were grouped to those who had a secondary meniscus tear within 2 years following anterior cruciate ligament reconstruction and those who did not. Univariate analysis and multivariable regression analysis was conducted to identify significant risk factors for a secondary meniscus tear.

RESULTS

There were 25,622 patients meeting criteria for inclusion in this study. Within 2 years from the primary anterior cruciate ligament reconstruction, there were 1,781 patients (7.0%) that experienced a meniscus tear. Graft failure had the highest odds of having a postoperative meniscus tear within 2 years (OR: 4.1; CI 3.5-4.8; p < 0.002). Additional significant risk factors included tobacco use (OR: 2.0; CI 1.0-3.1; p < 0.001), increased Charlson Comorbidity Index (OR: 1.2; CI 1.1-1.4), male gender (OR: 1.1; CI 1.1-1.2; p < 0.001), obesity (OR: 1.1; CI 1.1-1.2; p < 0.001), delayed surgery (OR:1.1; CI 1.1-1.2; p < 0.002), and patients age 30 and older (OR: 1.0; CI 1.0-1.0; p < 0.001).

CONCLUSIONS

This study found that anterior cruciate ligament graft failure is the strongest predictor of post-operative meniscus tears. Other risk factors, including tobacco use, increased CCI, male gender, obesity, delayed surgery, and age 30 and older, were established, with several being modifiable. Therefore, targeted preoperative optimization of modifiable risk factors and postoperative protocols may reduce the risk of secondary meniscus tears.

LEVEL OF EVIDENCE

Level III, prognostic trial.

The effect of obesity on complications following isolated posterior cruciate ligament reconstruction

BACKGROUND

This study assessed the risk of 30-day complications for obese patients compared to non-obese patients undergoing isolated posterior cruciate ligament (PCL) reconstruction.

METHODS

From 2006 to 2019, the National Surgical Quality Improvement Program database was queried for patients undergoing isolated PCL reconstruction. Two patient cohorts were defined: patients with obesity (BMI ≥ 30.0 kg/m²) and patients without obesity (BMI < 30 kg/m²). Patients' baseline demographics and medical comorbidities were collected and compared between the cohorts. Postoperative outcomes were assessed using bivariate and multivariate analyses.

RESULTS

414 patients underwent PCL reconstruction. 258 patients (62.3%) were non-obese and 156 patients (37.7%) were obese. Obese patients were more likely to be older, have a higher American Society of Anesthesiologists classification, and have hypertension compared to non-obese patients (p < 0.05 for all). The rates of superficial surgical site infections, wound dehiscence, transfusion necessity, deep vein thrombosis, and re-operation were not significant between obese and non-obese patients. Following adjustment on multivariate analyses, relative to patients without obesity, those with obesity had an increased risk of admission to the hospital overnight (OR 1.66; p = 0.048).

CONCLUSIONS

To our knowledge, this is the first study to evaluate obesity on complications in isolated PCL reconstruction. Our results and the heterogeneity in the literature indicate that obesity significantly impacts the rates of hospital readmission for PCL reconstruction. Therefore, surgeons should carefully weigh the risks and benefits of operating on obese patients and plan accordingly as obese patients may require postoperative hospital admission after PCL reconstruction.

LEVEL OF EVIDENCE

III.

Anterior cruciate ligament tear increases the risk of venous thromboembolism: a population-based cohort study

PURPOSE

Previous studies highlighted an increased risk of venous thromboembolism (VTE) among patients with anterior cruciate ligament reconstruction (ACLR); however, the risk for those with ACL tear but without undergoing ACLR has not been reported yet. The aim of this study was to evaluate the risk of VTE among ACL tear individuals with or without ACLR derived from the general population.

METHODS

A cohort study was conducted using data from the IQVIA Medical Research Database of the United Kingdom. Up to five non-ACL tear individuals (n = 22,235) were matched to each case of ACL tear (n = 4474) by age, sex, body mass index and entry-time. The relation of ACL tear to VTE [pulmonary embolism (PE) and deep vein thrombosis (DVT)] was examined using a multivariable Cox proportional hazard model. A sub-cohort analysis, in which the ACL tear individuals were stratified into those with ACLR and those without ACLR, was also conducted.

RESULTS

VTE developed in 13 individuals with ACL tear and nine individuals without ACL tear (incidence rates: 3.1 vs. 0.4/1000 person-years), with multivariable-adjusted hazard ratio (HR) being 6.59 (95% CI 2.28-19.08) in 1-year follow-up. For ACL tear individuals with ACLR, the HR was 11.44 (95% CI 2.71-48.28), and for those without ACLR, the HR was 6.02 (95% CI 1.44-24.25), compared with individuals without ACL tear.

CONCLUSION

This large-sample population-based cohort study provides the first evidence on an increased risk of VTE in ACL tear individuals regardless of subsequent ACLR, which supports the necessity for monitoring venous-thromboembolic complications in the target population, including those without ACLR.

LEVEL OF EVIDENCE

III.

Operative Time Less Than 1.5 Hours, Male Sex, Dependent Functional Status, Presence of Dyspnea, and Reoperations Within 30 days Are Independent Risk Factors for Readmission After ACLR

Purpose

The purposes of this study are to use a large, patient-centered database to describe the 30-day readmission rate and to identify predictive risk factors for readmission after elective isolated ACLR.

Methods

The National Surgical Quality Improvement Program Database was retrospectively queried for isolated ACLR procedures between 2011 and 2017. Current Procedural Terminology (CPT) codes were used to identify isolated ACLR patients. Those undergoing additional procedures such as meniscectomy or multi-ligamentous reconstruction were excluded. Readmissions were analyzed against demographic variables with bivariate analysis. Multivariate logistic regression was used to find independent risk factors for 30-day readmissions after ACLR.

Results

A total of 11,060 patients (37.2% female) were included with an average age of 32.2 ± 10.6 years and mean body mass index (BMI) of 27.9 ± 6.5 kg/m² (29.2% were >30). The overall readmission rate was 0.59%. The most reported reason for readmission was infection 0.22 (24 out of 11,060). The following variables were associated with significantly higher readmission rates: male sex (P = .001), history of severe chronic obstructive pulmonary disease (COPD) (P = .025), cardiac comorbidity (P = .034), operative time >1.5 hours (P <.001), partially dependent functional health status (P = .002), high preoperative creatinine (P = .009), normal preoperative albumin (P = .020), hypertension (P = .034), and reoperations (P < .001). Operative time >1.5 hours, male sex, dependent functional status, the presence of dyspnea, and undergoing a reoperation were identified as independent risk factors for 30-day readmissions (P < .05 for all).

Conclusions

Isolated ACLR is associated with low 30-day readmission rates. Operative time >1.5 hours, male sex, dependent functional status, the presence of dyspnea, and 30-day reoperations are independent risk factors for readmission that should be considered in patient selection and addressed with preoperative counseling.

Level of Evidence

Level III, retrospective cohort study.

Incidence and risk factors for symptomatic venous thromboembolism following anterior cruciate ligament reconstruction

PURPOSE

To determine the incidence of symptomatic venous thromboembolism (VTE) following anterior cruciate ligament (ACL) reconstruction using a large national database and to identify corresponding independent risk factors.

METHODS

The Humana administrative claims database was reviewed for patients undergoing ACL reconstruction from 2007 to 2017. Patient demographics, medical comorbidities, as well as concurrent procedures were recorded. Postoperative incidence of VTE was measured by identifying symptomatic deep vein thrombosis (DVT) and pulmonary embolism (PE) at 30 days, 90 days, and 1 year postoperatively. Univariate analysis and binary logistic regression were performed to determine independent risk factors for VTE following surgery.

RESULTS

A total of 11,977 patients were included in the study. The incidence of VTE was 1.01% (n = 120) and 1.22% (n = 146) at 30 and 90 days, respectively. Analysis of VTE events within the first postoperative year revealed that 69.6% and 84.3% of VTEs occurred within 30 and 90 days of surgery, respectively. Logistic regression identified age ≥ 45 (odds ratio [OR] = 1.88; 95% confidence interval [CI] 1.32-2.68; p < 0.001), inpatient surgery (OR = 2.07; 95% CI 1.01-4.24; p = 0.045), COPD (OR = 1.51; 95% CI 1.02-2.24; p = 0.041), and tobacco use (OR = 1.75; 95% CI 1.17-2.62; p = 0.007), as well as concurrent PCL reconstruction (OR = 3.85; 95% CI 1.71-8.67; p = 0.001), meniscal transplant (OR = 17.68; 95% CI 3.63-85.97; p < 0.001) or osteochondral allograft (OR = 15.73; 95% CI 1.79-138.43; p = 0.013) as independent risk factors for VTE after ACL reconstruction.

CONCLUSIONS

The incidence of symptomatic postoperative VTE is low following ACL reconstruction, with the majority of cases occurring within 90 days of surgery. Risk factors include age ≥ 45, inpatient surgery, COPD, tobacco use and concurrent PCL reconstruction, meniscal transplant or osteochondral allograft.

LEVEL OF EVIDENCE

III.

Artificial Intelligence Predicts Cost After Ambulatory Anterior Cruciate Ligament Reconstruction

Purpose

To develop and internally validate a machine-learning algorithm to reliably predict cost after anterior cruciate ligament reconstruction (ACLR).

Methods

A retrospective review of the New York State Ambulatory Surgery and Services database was performed to identify patients who underwent elective ACLR from 2015 to 2016. Features included in initial models consisted of patient characteristics (age, sex, insurance status, income, medical comorbidities as classified by the Clinical Classifications Software diagnosis code) as well as intraoperative variables (type of anesthesia and procedure-specific factors). Models were generated to predict total charges using 4 algorithms: random forest, extreme gradient boost, elastic net penalized regression, and support vector machines with radial kernels. Training was performed with 10-fold cross-validation followed by internal validation via 0.632 bootstrapping. Model discriminative performance was assessed by area under the receiver operating characteristic curve, calibration, and the Brier score. Decision curve analysis was performed to demonstrate the net benefit of using the final model in practice.

Results

In total, 7,311 patients undergoing ambulatory ACLR were included. The random forest model demonstrated the best performance assessed via internal validation (area under the curve = 0.85), calibration, and the Brier score (0.208). Cost incurred was influenced by anesthesia type, operating room time, and number of chronic comorbidities. Decision curve analysis revealed a net benefit for use of the random forest model and the model was integrated into a web-based open-access application.

Conclusions

The random forest model predicted cost after ambulatory ACLR using a large, statewide database with good performance. The top variables found to predict increased charges were general anesthesia, operating room time, meniscal repair, self-pay insurance, patient neighborhood characteristics, and number of chronic conditions.

Level of Evidence

III, retrospective cohort study.

Multi-ligament reconstructions as a risk factor for adverse outcomes in arthroscopic surgery

PURPOSE

Multi-ligament knee injuries are a serious consequence of knee dislocation with a poorly evaluated post-operative complication profile due to low incidence. The aim of this study is to assess the risk of adverse post-operative events associated with operative management of multi-ligament knee injuries.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients undergoing surgical procedures for multi-ligament knee injuries from 2006 to 2016 using Current Procedural Terminology codes. We evaluated data on patient demographics and used a propensity score algorithm to adjust for baseline differences in these patients and developed univariate and multivariate logistic regression models to assess effects on minor and severe 30-day post-operative complications.

RESULTS

We identified 444 patients in this database who underwent multi-ligament knee reconstructions between 2006 and 2016. After propensity matching, minor and major adverse post-operative events were more frequent in patients with multi-ligament knee injuries (1.4% vs 0.2%, p < 0.001 and 2.7% vs 1.1%, p = 0.002, respectively). Patients with multi-ligament knee injuries experienced a 55-fold increase risk of need for transfusion (p < 0.001) and a fivefold increased risk of pulmonary embolism (p = 0.025), with most occurring in bicruciate reconstructions (Schenck Classification KD-III and KD-IV injuries).

CONCLUSION

The surgical management of multi-ligament knee injuries confers significant increased risk of 30-day post-operative minor or severe adverse event over arthroscopic ACL reconstruction. These patients are most at risk for post-operative blood transfusion requirement, and pulmonary embolism, with patient's undergoing surgery for bicruciate ligament injuries at particularly high risk of complication.

LEVEL OF EVIDENCE

IV.

Increased hip arthroscopy operative duration is an independent risk factor for overnight hospital admission

PURPOSE

The purpose of this study was to determine the association between operative duration and short-term complications as well as overnight hospital admission following hip arthroscopy.

METHODS

Hip arthroscopy cases from 2006 to 2016 were retrieved from the National Surgical Quality Improvement Program registry, which prospectively collects 30-day postoperative complications. Patients were stratified into the following groups based on procedure length: group 1 (< 60 min), group 2 (60-120 min), and group 3 (> 120 min). Preoperative characteristics were compared across the cohorts. Multivariate regressions were used to compare complication rates and overnight hospital admission between the three groups. Independent risk factors for overnight hospital admission were characterized.

RESULTS

A total of 2129 hip arthroscopy cases were identified. Average operative duration was 99.3 ± 55.7 min. As operative time increased, patients were more likely to be younger, male, and had lower American Society of Anesthesiologists (ASA) class (p < 0.001). Body mass index and comorbidity profiles were similar across the patient cohorts, with the exception of hypertension being more prevalent in the shorter operative time cohort (p < 0.001). Patients in group 3 were more likely to stay overnight in the hospital (26.0%) compared to patients in groups 1 (7.7%) and 2 (10.9%), p < 0.001). All postoperative complication rates were otherwise similar between the cohorts. Independent risk factors for overnight hospital admission included increasing operative time (most notably > 120 min relative to < 60 min, relative risk [RR] = 3.53, 95% CI 2.50-5.00, p < 0.001) and increasing ASA classification (most notably ASA III or IV relative to ASA I, RR = 1.64, 95% CI 1.18-2.27; p = 0.013).

CONCLUSIONS

Increasing operative duration was not associated with increased postoperative complications following hip arthroscopy. However, patients were more than three times likely to stay in the hospital overnight if their surgery was longer than 120 min, relative to cases that were less than 60 min.

LEVEL OF EVIDENCE

III.

Pharmacologic Thromboprophylaxis Other Than Aspirin Is Associated With Increased Risk for Procedural Intervention for Arthrofibrosis After Anterior Cruciate Ligament Reconstruction

PURPOSE

To compare rates of procedural intervention for arthrofibrosis following anterior cruciate ligament reconstruction (ACLR) among patients who were not prescribed any pharmacologic thromboprophylaxis compared with patients who were prescribed aspirin and to patients who were prescribed other agents.

METHODS

A search of a national insurance claims database was performed to identify all patients who underwent ACLR from 2007 to 2017 who were active within the database at a minimum of 6 months before and 18 months after their surgery. The primary outcome studied was a subsequent procedure for arthrofibrosis, manipulation under anesthesia, and lysis of adhesions (MUA/LOA). Patients who filled a prescription for aspirin, low-molecular weight heparin, direct factor Xa inhibitors, fondaparinux, and warfarin within 2 days after their surgery were included and those who filled a prescription within 3 months before surgery were excluded. Thromboprophylaxis status was defined as no thromboprophylaxis, aspirin, and any agent other than aspirin. Logistic regression analysis was performed to determine the association between prophylaxis status and MUA/LOA.

RESULTS

Of the 14,081 patients in our final surgical population, 191 patients had MUA/LOA and 13,890 patients did not. In total, 499 patients were prescribed pharmacologic prophylaxis. Rates of MUA/LOA across groups were 1.3% in the group with no thromboprophylaxis, 1.9% in the group prescribed aspirin, and 4.3% in the group prescribed any agent other than aspirin. Only the group prescribed an agent other than aspirin was significantly associated with subsequent procedure for arthrofibrosis (odds ratio 2.6, 95% confidence interval 1.3-4.8, P = .004).

CONCLUSIONS

Patients who were prescribed a pharmacologic agent other than aspirin had a 2.6 times greater likelihood of requiring a procedural intervention for arthrofibrosis following ACLR compared with patients who were not prescribed a thromboprophylaxis agent LEVEL OF EVIDENCE: III, Retrospective Cohort Study.

The impact of age on 30-day complications following shoulder instability surgery

HYPOTHESIS

The purpose of this study was to evaluate short-term outcomes including medical complications, overnight admission, and 30-day readmission with regard to patient age at the time of shoulder instability surgery.

METHODS

Patients undergoing surgery for glenohumeral instability were collected from the National Surgical Quality Improvement Program between the years of 2005 and 2016. These patients were separated into cohorts of younger than 25 years, 25-34 years, and older than 34 years. Medical complications, hospital admission, and 30-day readmission were compared using multivariate analysis.

RESULTS

Of the 5449 patients included, there were 2035 (37.0%) patients younger than 25 years, 1815 (33.0%) between 25 and 34 years, and 1649 (30.0%) 35 and older. Overall, 81.7% of patients underwent an arthroscopic Bankart repair, 12.6% of patients underwent an open Bankart repair, and 5.7% of patients underwent a Latarjet-Bristow procedure. The risk of 30-day readmission increased with age, ranging from 0.24% for <25 years old to 0.92% for 35 years and older (P = .040). Operative duration greater than 60 minutes (odds ratio [OR] 1.76; P = .001), duration greater than 90 minutes (OR 3.58; P < .001), and American Society of Anesthesiologists class III and IV (OR 1.80; P = .001) were associated with increased risk of overnight hospital stay. Compared with arthroscopic Bankart repair, the Latarjet-Bristow procedure was associated with increased total complications (OR 3.30; P = .021), overnight hospital stay (OR 4.64; P < .001), and 30-day readmission (OR 3.39; P = .013).

CONCLUSION

This study demonstrates that even in the relatively young and healthy shoulder instability patient cohort, patients older than 25 years are almost 4 times more likely to experience a complication. Additionally, Latarjet-Bristow procedures are 3-4 times more likely to experience a complication or readmission than other shoulder instability procedures.

Decline in Racial Disparities for United States Hospital Admissions After Anterior Cruciate Ligament Reconstruction From 2007 to 2015

Background

Racial disparities in perioperative complications have been shown to exist for many procedures in orthopaedic surgery. Although anterior cruciate ligament reconstruction (ACLR) is commonly performed as an outpatient procedure, the rate of admission to the hospital postoperatively is not insignificant. Hispanic patients have been shown to have higher odds of admission compared with non-Hispanic patients.

Hypothesis

We hypothesized that racial disparities would decrease from 2007 to 2015, resulting in lower rates of hospital admission for Black and Hispanic patients.

Study Design

Descriptive epidemiology study.

Methods

This study represents a retrospective analysis of the National Surgical Quality Improvement Program (NSQIP) database for patients undergoing ACLR between 2007 and 2015. We performed bivariate analysis as well as binary logistic regression, with postoperative admission as the primary outcome. Previously identified risk factors for admission were used as predictors in addition to a term for the statistical interaction between year of surgery and ethnicity.

Results

A total of 7542 patients undergoing ACLR were assessed. The logistic regression model showed that Hispanic patients had higher overall odds of admission (odds ratio [OR], 3.320; P < .001) than White patients; Black patients also had higher odds compared with White patients (OR, 1.929; P = .009). However, there was a significant interaction between year of surgery and both Black ethnicity (OR, 0.907; P = .026) and Hispanic ethnicity (OR, 0.835; P = .002), indicating a significant decrease in the admission rates for these minority patients compared with White patients over time. Other risk factors for admission were the use of regional anesthesia (OR, 3.482; P < .001), bleeding disorders (OR, 5.064; P = .002), a higher body mass index (OR, 1.029; P < .001), and longer operative times (OR, 1.012; P < .001). More recent surgery was associated with lower odds of admission (OR, 0.826; P < .001).

Conclusion

Admission rates after ACLR declined from 2007 to 2015. Black and Hispanic patients were more likely to be admitted overall, but they also saw a greater decrease in the odds of admission than White patients. This represents a reduction in disparity between the 2 groups and is a reassuring improvement in racial disparity trends after a common sports procedure.

Risk factors for hospital admission in patients undergoing outpatient anterior cruciate ligament reconstruction: A national database study

INTRODUCTION

Anterior Cruciate Ligament Reconstructions (ACLR) are routinely performed in an outpatient setting with low 90-day readmission rates (2.3%); however, admissions rates in the immediate perioperative period have been previously reported as high as 13.1%. Despite the surprisingly high number of patients requiring immediate perioperative admission, there has been a lack of recent literature specifically examining the associated risk factors for admission.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database, a query for patients who underwent ACLR from 2011 through 2018 was performed using Current Procedural Terminology codes. The following concomitant procedures were included: meniscectomy, meniscal repair, diagnostic arthroscopy, loose body removal, synovectomy, chondroplasty, abrasion chondroplasty, drilling for osteochondritis dissecans. Demographics including age, sex, race, body mass index (BMI) and comorbidities were collected. Perioperative factors collected were anesthesia type and operative times. Patient demographic and perioperative data were compared using Fisher's exact test and Pearson's chi-square test. Multivariate logistic regressions were used to calculate odds ratios (OR) and 95% confidence intervals (CI) of independent risk factors for postoperative admission. Holm-Bonferroni method yielded adjusted p-value thresholds for significance.

RESULTS

Of the 20,819 patients undergoing ACLR with and without concomitant procedures, 3.8% of patients were admitted to the hospital in the immediate postoperative period. Following multivariate regression analysis, increased odds of admission were demonstrated with the use of regional anesthesia alone (OR = 2.77, 95%CI: 2.22-3.44; p < 0.001), increasing concurrent procedures (Table 1), and obesity classes II (OR = 1.62, 95%CI: 1.26-2.10; p < 0.001) and III (OR = 1.81, 95%CI: 1.33-2.47; p < 0.001). Subsequent subgroup analysis of the isolated ACLR procedures (N = 9,423) demonstrated a 3.3% postoperative admission rate. Multivariate regressions demonstrated increased odds of admission with regional anesthesia use only (OR = 2.62, 95%CI: 1.90-3.60; p < 0.001), obesity class II (OR = 2.22, 95%CI: 1.51-3.26; p < 0.001), and increasing minutes of operative time (OR = 1.01, 95%CI: 1.01-1.01; p < 0.001). Table 2 demonstrates increasing rates and odds of admission with increasing operative time in hours.

CONCLUSION

Anterior Cruciate Ligament Reconstructions are routinely performed in an outpatient setting; nevertheless, a subset of ACLR patients is admitted postoperatively. We found an increased risk of admission with the use of regional anesthesia alone, increasing concurrent procedures and obesity classes II and III. A further understanding of patient risk factors for those undergoing ACLR allows orthopedic surgeons to better develop a preoperative plan and discuss patient expectations, which will lead to more efficient resource allocation and improved patient satisfaction.

Comparison of the clinical and cost effectiveness of two management strategies (rehabilitation versus surgical reconstruction) for non-acute anterior cruciate ligament (ACL) injury: study protocol for the ACL SNNAP randomised controlled trial

Background

Anterior cruciate ligament (ACL) rupture is a common knee injury that can lead to poor quality of life, decreased activity and increased risk of secondary osteoarthritis of the knee. Management of patients with a non-acute ACL injury can include a non-surgical (rehabilitation) or surgical (reconstruction) approach. However, insufficient evidence to guide treatment selection has led to high variation in treatment choice for patients with non-acute presentation of ACL injury.

The objective of the ACL SNNAP trial is to determine in patients with non-acute anterior cruciate ligament deficiency (ACLD) whether a strategy of non-surgical management (rehabilitation) (with option for later ACL reconstruction only if required) is more clinically effective and cost effective than a strategy of surgical management (reconstruction) without prior rehabilitation with all patients followed up at 18 months.

Methods

The study is a pragmatic, multi-centre, superiority, randomised controlled trial with two-arm parallel groups and 1:1 allocation. Patients with a symptomatic non-acute ACL deficient knee will be randomised to either non-surgical management (rehabilitation) or surgical management (reconstruction). We aim to recruit 320 patients from approximately 30 secondary care orthopaedic units from across the United Kingdom. Randomisation will occur using a web-based randomisation system. Blinding of patients and clinicians to treatment allocation will not be possible because of the nature of the interventions. Participants will be followed up via self-reported questionnaires at 6, 12 and 18 months. The primary outcome is the Knee injury and Osteoarthritis Outcome Score (KOOS) at 18 months post randomisation. Secondary outcomes will include a return to sport/activity, intervention-related complications, patient satisfaction, expectations of activity, generic health quality of life, knee specific quality of life and resource usage.

Discussion

At present, no evidence-based treatment of non-acute ACL deficiency exists, particularly in the NHS. Moreover, little consensus exists on the management approach for these patients. The proposed trial will address this gap in knowledge regarding the clinical and cost effectiveness of ACL treatment and inform future standards of care for this condition.

Trial registration

ISRCTN: 10110685. Registered on 16 November 2016. ClinicalTrials.gov: NCT02980367. Registered in December 2016.

Procedure length is independently associated with overnight hospital stay and 30-day readmission following anterior cruciate ligament reconstruction

PURPOSE

The purpose was to characterize the independent effect of procedure length on the rates of 30-day perioperative complications, hospital readmissions, and overnight hospital stay in patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR). We hypothesized that longer procedure length in primary ACLR increases the risk for post-operative complications.

METHODS

Primary ACLR cases from 2005 to 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program registry. Patients were categorized into two cohorts based on procedure length, either less than or greater than 90 min. Two equal-sized propensity-matched cohorts were generated to account for differences in baseline and operative characteristics. Thirty-day clinical outcomes were compared using bivariate analyses between propensity-matched groups that controlled for patient-specific factors and concurrent meniscal repair. Multivariate logistic regression models were used to identify independent predictors of hospital readmission and overnight hospital stay.

RESULTS

In total, 12,077 ACLR cases were identified. The rate of any 30-day complication was increased in longer procedures relative to shorter procedures (1.6% vs 0.9%, p = 0.006), as were the rates of returning to the operating room (0.6% vs 0.3%, p = 0.03), hospital readmission (1.0% vs 0.3%, p = 0.001), and overnight hospital stay (16.2% vs 6.0%, p < 0.001). Obesity was a risk factor for both hospital readmission and overnight hospital stay, while hypertension, diabetes, chronic obstructive pulmonary disease, and a smoking history were associated with increased rates of overnight hospital stay. The most common reasons for hospital readmission were deep vein thrombosis or pulmonary embolism (25.0% of all readmitted patients), surgical site infection (25.0%), and post-operative pain (14.1%).

CONCLUSIONS

In this propensity-matched analysis adjusting for baseline patient characteristics and operative factors, procedure length of greater than or equal to 90 min in ACLR was independently associated with an increased risk of hospital readmission and overnight hospital stay. As a surrogate measure of surgical complexity, operative time may be a useful perioperative variable for post-operative risk stratification and patient counseling.

LEVEL OF EVIDENCE

III.

Increased Surgical Duration Associated With Prolonged Hospital Stay After Isolated Posterior Cruciate Ligament Reconstruction

Purpose

Although often performed using a variety of reconstructive techniques and strategies, no clinically significant differences presently exist between the approaches available for isolated PCL reconstructions. Given the operatively challenging nature of these procedures, there lies a potentially increased risk of postoperative complications and healthcare expenditures. Our investigation sought to identify patient and surgical risk factors associated with prolonged hospital stays following isolated PCL reconstruction and determine the incidence of 30-day complications after PCL reconstruction using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

Method

Patients undergoing isolated PCL reconstructions between 2005 and 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database using Current Procedural Terminology codes. Baseline patient and operative characteristics were evaluated as possible risk factors for overnight hospital admissions following PCL reconstruction and analyzed using multivariate analyses.

Results

A total of 249 patients were identified. Multivariate analyses demonstrated that increased operative duration >120 mins (OR 5.04, CI 2.44–10.40; p <0.001) was associated with an increased risk of overnight hospital stay. Major complications occurred in 0.4% (N=1), and minor complications occurred in 0.8% (N=2) with overall complications occurring in 1.2% (N=3) of all patients. Wound dehiscence was the only major complication while superficial surgical site infection and deep vein thrombosis were the only minor complications. 34.1% (N=85) of patients required an overnight hospital stay postoperatively.

Conclusion

Surgical duration >120 mins carried an increased risk of overnight hospital stay after isolated PCL reconstructions. As there are presently minimal significant clinical differences between current PCL reconstruction techniques, improved surgeon familiarity and comfort with a single technique is recommended to decrease operative time and avoid prolonged hospital stays and healthcare expenditures.

Level of evidence

III, retrospective comparative study.

Rates of Adverse Outcomes and Revision Surgery After Anterior Cruciate Ligament Reconstruction: A Study of 104,255 Procedures Using the National Hospital Episode Statistics Database for England, UK

BACKGROUND

After an anterior cruciate ligament (ACL) injury, ACL reconstruction is an elective procedure, and therefore, an understanding of the attributable risk from undergoing ACL reconstruction is necessary for patients to make a fully informed treatment decision.

PURPOSE

To determine the absolute risk of adverse outcomes including reoperation after ACL reconstruction with comparison, where possible, to the rate of adverse events reported in the general population.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

National hospital data on all ACL reconstructions performed in England between April 1, 1997, and March 31, 2017, were analyzed. Revision cases, bilateral procedures within 6 months, and cases with concurrent cartilage or multiple ligament surgery were excluded. The primary outcome was the occurrence of at least 1 serious complication (myocardial infarction, stroke, pulmonary embolism, infection requiring surgery, fasciotomy, neurovascular injury, or death) within 90 days. Additionally, 5-year rates of revision ACL reconstruction, contralateral ACL reconstruction, and meniscal surgery were investigated.

RESULTS

There were 133,270 ACL reconstructions performed, of which 104,255 were eligible for analysis. Within 90 days, serious complications occurred in 675 (0.65% [95% CI, 0.60-0.70]), including 494 reoperations for infections (0.47% [95% CI, 0.43-0.52]) and 129 for pulmonary embolism (0.12% [95% CI, 0.10-0.15]). Of 54,275 procedures with at least 5 years' follow-up, 1746 (3.22% [95% CI, 3.07-3.37]) underwent revision ACL reconstruction in the same knee, 1553 underwent contralateral ACL reconstruction (2.86% [95% CI, 2.72-3.01]), and 340 underwent meniscal surgery (0.63% [95% CI, 0.56-0.70]). The overall risk of serious complications fell over time (adjusted odds ratio [OR], 0.96 per year [95% CI, 0.95-0.98]); however, older patients (adjusted OR, 1.11 per 5 years [95% CI, 1.07-1.16]) and patients with a greater modified Charlson Comorbidity Index (adjusted OR, 2.41 per 10 units [95% CI, 1.65-3.51]) were at a higher risk. For every 850 (95% CI, 720-1039) ACL reconstructions, 1 pulmonary embolism could be provoked. For every 213 (95% CI, 195-233), 1 native knee joint infection could be provoked.

CONCLUSION

The overall risk of adverse events after ACL reconstruction is low; however, some rare but serious complications, including infections or pulmonary embolism, may occur. Around 3% of patients undergo further ipsilateral or contralateral ACL reconstruction within 5 years. These data will inform shared decision making between clinicians and patients considering their treatment options.

Should We Question the External Validity of Database Studies? A Comparative Analysis of Demographics

PURPOSE

To define the external validity of national and institutional databases for common sports medicine procedures.

METHODS

Patient demographic data including age, sex, body mass index (BMI), and 4 racial categories were aggregated between 2007 and 2016 across 2 databases for 4 common sports medicine procedures: anterior cruciate ligament reconstruction, arthroscopic rotator cuff repair (RCR), partial meniscectomy (PMx), and both arthroscopic and open shoulder stabilization. The first database of interest was a prospectively collected institutional database. The second was the National Surgical Quality Improvement Program (NSQIP) database. Two-sample t tests were performed to examine mean differences (MDs) in age and BMI, and χ² testing was used to test differences in sex and race.

RESULTS

A total of 7,019 institutional and 108,881 NSQIP patients were examined. The NSQIP cohort was significantly older (MD, 1.40 years), included more female patients (42.60% female patients vs 35.67% female patients), and showed a different racial distribution compared with the institutional data (all P < .0001). The NSQIP PMx cohort (MD, 7.38 years) was significantly older and the NSQIP RCR cohort (MD, 1.97 years) was significantly younger than their institutional counterparts (all P < .0001). The NSQIP anterior cruciate ligament reconstruction cohort (MD, 2.53) showed a greater average BMI (P < .0001). The NSQIP RCR cohort (41.8% female patients vs 33.3% female patients) and PMx cohort (46.0% female patients vs 37.9% female patients) also included more female patients. Race was distributed variably between databases for each procedure code (all P < .0001).

CONCLUSIONS

Significant differences in age, BMI, sex, and race distributions were observed between an institutional database and the NSQIP database. This study underlines the importance of defining the generalizability of database research, particularly when significant demographic differences between databases may underlie differences in postoperative outcomes.

LEVEL OF EVIDENCE

Level III, cross-sectional study.

Risk Factors for 30-Day Complications After Thumb CMC Joint Arthroplasty: An American College of Surgeons National Surgery Quality Improvement Program Study

BACKGROUND

The first carpometacarpal (CMC) joint is a common site of osteoarthritis, with arthroplasty being a common procedure to provide pain relief and improve function with low complications. However, little is known about risk factors that may predispose a patient for postoperative complications.

METHODS

All CMC joint arthroplasty from 2005 to 2015 in the prospectively collected American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database were identified. Bivariate testing and multiple logistic regressions were performed to determine which patient demographics, surgical variables and medical comorbidities were significant predictors for complications. These included wound related, cardiopulmonary, neurological and renal complications, return to the operating room (OR) and readmission.

RESULTS

A total of 3344 patients were identified from the database. Of those, 45 patients (1.3%) experienced a complication including wound issues (0.66%), return to the OR (0.15%) and readmission (0.27%) amongst others. When performing bivariate analysis, age over 65, American Society of Anesthesiologists (ASA) Class, diabetes and renal dialysis were significant risk factors. Multiple logistic regression after adjusting for confounding factors demonstrated that insulin-dependent diabetes and ASA Class 4 had a strong trend while renal dialysis was a significant risk factor.

CONCLUSIONS

CMC arthroplasty has a very low overall complication rate of 1.3% and wound complication rate of 0.66%. Diabetes requiring insulin and ASA Class 4 trended towards significance while renal dialysis was found to be a significant risk factors in logistic regression. This information may be useful for preoperative counseling and discussion with patients who have these risk factors.

Effect of Operative Time on Short-Term Adverse Events After Isolated Anterior Cruciate Ligament Reconstruction

Background:

A longer operative time has been previously recognized as a risk factor for short-term complications after various orthopaedic procedures; however, it has yet to be investigated as an independent risk factor for postoperative complications after anterior cruciate ligament (ACL) reconstruction.

Purpose:

To identify whether a longer operative time in ACL reconstruction is an independent risk factor for the development of postoperative complications, hospital readmissions, or an extended length of stay within 30 days of the index procedure.

Study Design:

Descriptive epidemiology study.

Methods:

Patients undergoing ACL reconstruction between 2005 and 2016 were identified using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Cases with concomitant procedures were excluded from the analysis. We evaluated the association between operative time and preoperative variables such as patient age, sex, body mass index, comorbidities, and procedure. Correlations between adverse events and operative time, while controlling for the above preoperative variables, were calculated using multivariate Poisson regression with robust error variance.

Results:

A total of 14,159 procedures were included in this investigation. The mean patient age was 32.6 ± 10.8 years, the mean body mass index was 27.7 ± 6.5 kg/m², and the mean operative time was 89.7 ± 28.6 minutes. Patients who were between the ages of 18 and 30 years (mean operative time, 95.1 ± 27.8 minutes; relative risk [RR], 17.7; P < .001), male (mean operative time, 91.9 ± 28.3 minutes; RR, 4.7; P < .001), and nondiabetic (mean operative time, 89.8 ± 28.6 minutes; RR, 7.1; P = .011) were associated with a longer operative duration. The overall complication rate was 1.1%. After adjusting for demographic characteristics and procedures, 15-minute incremental increases in operative duration were associated with an increased risk of deep vein thrombosis (RR, 1.12; P = .042), surgical site infections (RR, 1.21; P = .001), and sepsis (RR, 1.66; P < .001) as well as increased readmission rates (RR, 1.23; P = .001) and an extended length of stay (RR, 1.18; P = .008).

Conclusion:

While the overall adverse risk rate after ACL reconstruction remains low, marginal increases in operative time are associated with an increased risk of adverse events such as deep vein thrombosis, surgical site infections, sepsis, an extended length of stay, and readmissions. Thus, the operating physician and surgical staff should make all efforts to coordinate and prepare for each case to maximize surgical efficiency.

The Effect of Obesity on Operative Times and 30-Day Readmissions After Anterior Cruciate Ligament Reconstruction

PURPOSE

To understand the effect of obesity on operative times and 30-day readmission rates after arthroscopic anterior cruciate ligament reconstruction (ACLR).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried using Current Procedural Terminology billing codes to identify all patients aged 18 years and older who underwent ACLR between 2007 and 2014. The Student t test was used for continuous variables, and the χ-square or Fisher exact test was used for categorical variables. Multivariate analysis was conducted to identify factors associated with 30-day readmission.

RESULTS

We identified 9,000 patients who underwent ACLR. In the readmission analysis, the total readmission rate was 0.70%. After multivariate analysis, a body mass index (BMI) of 40 or greater was associated with a significantly increased risk of 30-day readmission (odds ratio, 3.06; 95% confidence interval, 1.09-8.57). An operative time of less than 80 minutes was associated with a decreased risk of readmission (odds ratio, 0.40, 95% confidence interval, 0.18-0.92). In the operative-time analysis, the mean operative time was 100.7 minutes. Older age was predictive of decreasing operative time, with the operative time being 32.75 minutes shorter in patients aged 65 years or older than in those younger than 25 years. After multivariate analysis, class II obesity (BMI of 35-39.9) predicted an increase of 7.11 minutes and class III obesity (BMI ≥ 40) predicted an increase of 8.70 minutes compared with normal weight (BMI of 18.5-24.9).

CONCLUSIONS

Obesity is associated with longer operative times and increased 30-day readmissions after ACLR, with patients with a BMI of 40 or greater having over 3 times the risk of readmission compared with patients with a normal weight. Male sex, black race, and younger age are all also associated with increased operative times.

LEVEL OF EVIDENCE

Level III, observational, retrospective cohort study.

Risk Factors for Deep Vein Thrombosis or Pulmonary Embolus Following Anterior Cruciate Ligament Reconstruction

Background:

Nearly 350,000 Americans develop a deep venous thromboembolism (DVT) or pulmonary embolism (PE) annually, and nearly 100,000 Americans die from these events. To date, little research has investigated patient-specific risk factors that increase the rate of DVT/PE following anterior cruciate ligament reconstruction (ACLR).

Purpose:

To determine relevant patient risk factors for the development of DVT/PE following ACLR.

Study Design:

Case-control study; Level of evidence, 3.

Methods:

All instances of ACLR from 2005 to 2014 within the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) prospective database were analyzed. Both univariate analysis and binary logistic regression were performed to determine which patient demographics and surgical factors were associated with DVT or PE following surgery.

Results:

Of the 9146 patients who underwent ACLR, 46 (0.5%) developed postoperative DVT, 8 (0.1%) developed PE, and 5 (0.05%) developed both. The following variables were associated with the development of DVT or PE on univariate analysis: increased age, a high tibial osteotomy (HTO) performed at the time of ACLR, microfracture performed, the presence of hypertension requiring medical therapy, and the presence of an active wound infection. Independent predictors of DVT or PE on multivariate analysis included HTO (odds ratio [OR], 22.7), the presence of an active wound infection (OR, 11.0), or hypertension requiring medication (OR, 2.2). Meniscal repair was not a risk factor for DVT or PE on univariate or multivariate analysis.

Conclusion:

In a review of 9146 patients undergoing ACLR, 46 (0.5%) developed DVT in the 30-day postoperative period. Increasing age over 30 years, concomitant HTO or microfracture, hypertension requiring medication, and presence of wound infection were all associated with an increased risk of DVT. The annual incidence of DVT/PE following ACLR reconstruction is low (<1%) and has not changed over time.

Factors Associated With Physician Loss in Anterior Cruciate Ligament Reconstruction Malpractice Lawsuits

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction is among the most common orthopaedic procedures, with its incidence doubling over the past decade. To date, no studies have analyzed litigation after ACL reconstruction.

PURPOSE

To characterize the causes of malpractice litigation after ACL reconstruction.

STUDY DESIGN

Cross-sectional study.

METHODS

A retrospective review of malpractice lawsuits after ACL reconstruction was performed using VerdictSearch, a large legal claims database encompassing nearly 180,000 legal cases, from February 1988 to May 2015. Settlement rates and physician loss rates were calculated along with 95% CIs for each complication type, and analysis of variance was used to compare all indemnity payments.

RESULTS

Of a total 30 lawsuits, 5 (16.7%) settled out of court. The 3 most common complications leading to litigation were prolonged pain (n = 5, 16.7%), infection (n = 5, 16.7%), and malpositioned graft (n = 5, 16.7%). Of the 25 cases that went to court, 8 (32.0%) ended in favor of the plaintiff (physician loss). Damage to a neurovascular structure resulted in the highest indemnity payment (mean, $2,012,926 ± $1,076,530; P = .021). Lawsuits for which pain or loss of range of motion was the only complication were significantly more likely to end in a physician victory (P = .04) and lower indemnity payments ($87,500 vs $678,715, respectively). Cases that involved a surgical technical error were more likely to result in a physician loss (P = .01), with malpositioned grafts having a significantly higher loss rate than average (75% vs 32%, respectively).

CONCLUSION

After ACL reconstruction, physicians are more likely to win malpractice suits if pain or limited range of motion is the only complaint and less likely to win if a surgical error was alleged. These findings may help to set patient expectations and provide adequate guidance during the informed consent process.

Risk Factors for Hospital Admission Following Arthroscopic Bankart Repair

Arthroscopic Bankart repair, a commonly performed procedure in the United States, is usually done on an outpatient basis. All instances of arthroscopic Bankart repair from 2005 to 2014 from the American College of Surgeons National Surgical Quality Improvement Program prospective database were analyzed. Both univariate analysis and binary logistic regression were performed to determine risk factors for admission following surgery. Of 2291 patients undergoing arthroscopic Bankart repair, 173 (7.6%) required inpatient hospital admission following surgery. Univariate analysis found the following to be associated with admission: female sex (P=.009), age older than 40 years (P<.001), white race (P=.002), body mass index greater than 30 kg/m² (P=.001), and American Society of Anesthesiologists class greater than 3 (P<.001). Independent predictors of admission on multivariate analysis included female sex (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.06-2.10; P=.023), increasing age (per year) (OR, 1.03; 95% CI, 1.02-1.04; P<.001), diabetes (OR, 2.70; 95% CI, 2.30-3.10; P=.006), and longer operation time (per minute) (OR, 1.010; 95% CI, 1.009-1.011; P<.001). This study identified a 7.6% rate of admission following arthroscopic Bankart repair, with diabetes, female sex, increasing age, and longer operation time being independent risk factors for admission. Knowledge of these risk factors is important when setting patient expectations preoperatively and for optimizing care to obtain the best short-term outcome. [Orthopedics. 2017; 40(5):e855-e861.].

Comparative outcomes of outpatient and inpatient total shoulder arthroplasty: an analysis of the Medicare dataset

AIMS

The aim of the present study was to compare the 30- and 90-day re-admission rates and complication rates of outpatient and inpatient total shoulder arthroplasty (TSA).

PATIENTS AND METHODS

The United States Medicare Standard Analytical Files database was questioned to identify patients who had undergone outpatient or inpatient TSA between 2005 and 2012. Patient characteristics were compared between the two groups using chi-squared analysis. Multivariate logistic regression analysis was used to control for differences in baseline patient characteristics and to compare the two groups in terms of post-operative complications within 90 days and re-admission within 30 days and 90 days.

RESULTS

A total of 123 347 Medicare subscribers underwent TSA between 2005 and 2012; 3493 (2.8%) had the procedure performed as an outpatient. A significantly greater proportion of patients who underwent TSA as inpatients were women, had a history of smoking, and had a greater incidence of medical comorbidity including diabetes, coronary artery disease, congestive heart failure, and chronic kidney disease (p < 0.05 for all). Re-admission rates were significantly higher for inpatients at both 30 days (0.83% versus 0.60%, p = 0.016, odds ratio 1.8) and 90 days (2.87% versus 2.04%, p < 0.001, odds ratio 1.8). Complications, including thromboembolic events (p < 0.001) and surgical site infection (p = 0.002), were significantly higher in inpatients.

CONCLUSION

Patients who underwent TSA on an outpatient basis were overall younger and healthier than those who had inpatient surgery, which suggests that patient selection was taking place. After controlling for age, gender, and medical conditions, patients who underwent TSA as outpatients had lower rates of 30- and 90-day re-admission and a lower rate of complications than inpatients. Cite this article: Bone Joint J 2017;99-B:934-8.

Comparison of 30-Day Morbidity and Mortality After Arthroscopic Bankart, Open Bankart, and Latarjet-Bristow Procedures: A Review of 2864 Cases

Background:

Surgical intervention for anterior shoulder instability is commonly performed and is highly successful in reducing instances of recurrent instability.

Purpose:

To determine and compare the incidence of 30-day complications and patient and surgical risk factors for complications for arthroscopic Bankart, open Bankart, and Latarjet-Bristow procedures.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

All arthroscopic Bankart, open Bankart, and Latarjet-Bristow procedures from 2005 to 2014 from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) prospective database were analyzed. Baseline patient variables were assessed, including the Charlson Comorbidity Index (CCI). Outcomes measures included length of operation, length of hospital stay, need for hospital admission, 30-day readmission, and 30-day return to the operating room. Binary logistic regression was performed for the presence of any complications after all 3 procedures.

Results:

There were 2864 surgical procedures (410 open Bankart, 163 Latarjet-Bristow, and 2291 arthroscopic Bankart) included. There was no significant difference with regard to age (P = .11), body mass index (P = .17), American Society of Anesthesiologists class (P = .423), or CCI (P = .479) for each group. The Latarjet-Bristow procedure had the highest overall complication rate (5.5%) compared with open (1.0%) and arthroscopic (0.6%) Bankart repairs. The Latarjet-Bristow procedure had significantly longer mean operative times (P < .001) in addition to the highest 30-day return rate to the operating room (4.3%; 95% confidence interval, 1.2%-7.4%). Smoking status was an independent predictor of a postoperative complication (P = .05; odds ratio, 8.0) after Latarjet-Bristow.

Conclusion:

Surgical intervention for anterior shoulder instability has a low rate of complication (arthroscopic Bankart, 0.6%; open Bankart, 1.0%; Latarjet-Bristow, 5.5%) in the early postoperative period, with the most common being surgical site infection, deep vein thrombosis, and return to the operating room.

Risk Factors for Hospital Admission After Anterior Cruciate Ligament Reconstruction

PURPOSE

To determine patient and surgical risk factors for admission after anterior cruciate ligament reconstruction (ACLR) using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database.

METHODS

All instances of ACLR from 2005 to 2014 from the ACS NSQIP prospective database were analyzed. Both univariate analysis and binary logistic regression were performed to determine which patient demographics and medical comorbidities were associated with admission after surgery.

RESULTS

Of the 9,146 patients undergoing ACLR, 1,197 (13.1%) required admission. Univariate analysis found that the following variables were associated with the need for admission: decreased age, Hispanic ethnicity, higher American Society of Anesthesiologists class, higher Charlson Comorbidity Index, use of an epidural anesthesia, longer operative times, prior operation within 30 days, dyspnea, smoking, diabetes, chronic obstructive pulmonary disease, previous cardiac surgery, hypertension, previous revascularization procedure, and a known bleeding disorder. Independent predictors of admission on multivariate analysis included Hispanic ethnicity (odds ratio [OR] 8.9), use of epidural anesthesia (OR 6.3), known bleeding disorder (OR 4.02), increased body mass index (OR 1.03), longer operation time (OR 1.012), and younger age (OR 1.008).

CONCLUSIONS

Our study identifies Hispanic ethnicity, use of epidural anesthesia, and history of bleeding disorder as major independent risk factors for admission after ACLR.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

The effect of smoking on ACL reconstruction: a systematic review

OBJECTIVE

Anterior cruciate ligament reconstruction (ACLR) depends on proper healing of the graft or bone plug at the cellular level. The effect of cigarette smoke on ACLR was not commonly reported until recently. The primary purpose of this review was to determine if smoking has a negative effect on subjective or objective outcome scores after ACLR. The secondary purpose was to identify any increased risk of complications, infection, ACL re-tear, or revision procedures.

METHODS

A systematic literature review of the MEDLINE, SCOPUS and PubMed databases was performed to identify all studies that compared outcomes of ACLR surgery between smokers and nonsmokers. The frequency-weighted mean was calculated for outcome measures that were similar across several studies.

RESULTS

Seventeen studies were identified that met inclusion criteria for patients undergoing ACLR (mean age, 26.8 years) with a mean follow-up of 37 months. Smokers had significantly worse subjective outcome measures and worse side-to-side difference in anterior translation compared to non-smokers (2.68 mm vs 1.89 mm, respectively). In 2 studies, smokers were found to have a significantly higher risk of developing an infection and VTE (venous thromboembolism) post-operatively. The evidence for the effect of smoking on risk for subsequent re-tear is mixed. No study reported a higher rate of development of radiographic knee osteoarthritis among smokers compared to nonsmokers.

CONCLUSIONS

Cigarette smoke is associated with significantly worse clinical outcome scores, an increase in anterior translation, and increased complication rates after ACL reconstruction. These findings may help orthopaedic surgeons better inform their patients about the potential negative effects of smoking on the outcomes of ACL reconstruction.

LEVEL OF EVIDENCE

Therapeutic Level IV.