Heather A. Prentice

Patient demographic and surgical characteristics in anterior cruciate ligament reconstruction: a description of registries from six countries

Objective Findings from individual anterior cruciate ligament reconstruction (ACLR) registry studies are impactful, but how various registries from different countries compare with different patient populations and surgical techniques has not been described. We sought to describe six ACLR registry cohorts to understand variation across countries. Methods Five European registries and one US registry participated. For each registry, all primary ACLR registered between registry establishment through 31December 2014 were identified. Descriptive statistics included frequencies, proportions, medians and IQRs. Revision incidence rates following primary ACLR were computed. Results 101 125 ACLR were included: 21u2009820 in Denmark, 300 in Luxembourg, 17u2009556 in Norway, 30u2009422 in Sweden, 2972 in the UK and 28u2009055 in the US. In all six cohorts, males (range: 56.8%–72.4%) and soccer injuries (range: 14.1%–42.3%) were most common. European countries mostly used autografts (range: 93.7%–99.7%); allograft was most common in the US (39.9%). Interference screw was the most frequent femoral fixation in Luxembourg and the US (84.8% and 42.9%), and suspensory fixation was more frequent in the other countries (range: 43.9%–75.5%). Interference was the most frequent tibial fixation type in all six cohorts (range: 64.8%–98.2%). Three-year cumulative revision probabilities ranged from 2.8% to 3.7%. Conclusions Similarities in patient demographics and injury activity were observed between all cohorts of ACLR. However, graft and fixation choices differed. Revision rates were low. This work, including >100 000 ACLR, is the most comprehensive international description of contemporary practice to date.

Reasons for Ninety-Day Emergency Visits and Readmissions After Elective Total Joint Arthroplasty: Results From a US Integrated Healthcare System

BACKGROUNDnPrevious studies evaluating reasons for 30-day readmissions following total joint arthroplasty (TJA) may underestimate hospital-based utilization of healthcare resources during a patients episode-of-care. We sought to identify common reasons for 90-day emergency department (ED) visits and hospital readmissions following primary elective unilateral TJA.nnnMETHODSnPatients from July 1, 2012 through June 30, 2015 having primary elective TJA and at least one 90-day postoperative ED-only visit and/or readmission for any reason were identified using the Kaiser Permanente Total Joint Replacement Registry. Chart reviews for ED visits/readmissions included 13 surgical and 11 medical reasons. The 2344 total hips and 5520 total knees were analyzed separately.nnnRESULTSnIncidence of at least one ED visit following total hip arthroplasty (THA) was 13.4% and 4.5% for readmissions. The most frequent reasons for ED visits were swelling (15.6%) and pain (12.8%); the most frequent reasons for readmissions were infection (12.5%) and unrelated elective procedures (9.0%). The incidence of at least one ED visit following total knee arthroplasty (TKA) was 13.8%, and the incidence of readmission was 5.5%. The most frequent reasons for ED visits were pain (15.8%) and swelling (15.6%); the most common readmission reasons were gastrointestinal (19.1%) and manipulation under anesthesia (9.4%).nnnCONCLUSIONnSwelling and pain related to the procedure were the most frequent reasons for 90-day ED visits after both THA and TKA. Readmissions were most commonly due to infection or unrelated procedures for THA and gastrointestinal or manipulation under anesthesia for TKA. Modifications to discharge protocols may help prevent or alleviate these issues, avoiding unnecessary hospital returns.

Effect of body mass index on patient outcomes of surgical intervention for the lumbar spine

BACKGROUNDnConflicting findings exist on the effect of obesity on outcomes of lumbar spine surgery; results depend on the diagnosis studied, procedure evaluated, definition of obesity, and specific outcomes measured. The purpose of this retrospective cohort study is to examine the effect of increasing body mass index (BMI) on surgical-related, health-related, and long-term outcomes of lumbar spine surgery in a single representative patient sample.nnnMETHODSnUsing a surgical registry from an integrated health care system, 8,049 instrumented lumbar spine cases were identified between 1/1/2009 and 09/30/2013. The sample was stratified into five BMI categories. Outcomes of interest included: (I) surgical-related factors and complications; (II) health-related complications; and (III) long-term complications. Mixed linear models, conditional logistic regressions, and survival analysis using a Cox regression model were conducted controlling for surgeon effects. Age, gender, diabetes status, smoking status, admitting diagnosis, and surgical approach were included as covariates.nnnRESULTSnEvery 5 kg/m2 increase in BMI was associated with a significant increase in surgical time (7.8 minutes), estimated blood loss (EBL) (36.5 mL), risk of deep infection (OR =1.7 times), and deep vein thrombosis (DVT) (OR =1.5). BMI was not associated with increased incidence of other intraoperative or health-related complications. Rate of re-operation was 1.1 times higher with every 5 kg/m2 increase in BMI, but rate of re-operation due to adjacent segment disease (ASD) was not associated with BMI.nnnCONCLUSIONSnObesity had an adverse effect on certain surgical-related, health-related and long-term surgical outcomes. The magnitude of this effect increased with increasing levels of obesity, which increases the medical burden associated with obesity.

Risk factors for postoperative opioid use after elective shoulder arthroplasty

BACKGROUNDnThe opioid epidemic remains a serious issue in the United States with significant impact to the medical and socioeconomic welfare of communities. We sought to determine baseline opioid use in patients undergoing shoulder arthroplasty (SA) and identify patient characteristics, comorbidities, and surgical risk factors associated with postoperative opioid use.nnnMETHODSnA Shoulder Arthroplasty Registry identified the number of dispensed opioid medication prescriptions (Rxs) in the first postoperative year in patients who underwent elective primary SA from 2008 to 2014. We used Poisson regression to study the effect of preoperative risks factors on number of dispensed opioid Rxs in the first postoperative year, evaluated quarterly (Q1: days 0-90, Q2: days 91-180, Q3: days 181-270, Q4: days 271-360).nnnRESULTSnIncluded were 4243 SAs from 3996 patients, and 75% used opioids in the 1-year preoperative period. The factors associated with increased opioid use in all postoperative quarters (Q4 incident rate ratio [IRR] shown) were age <60 years (IRR, 1.40; 95% confidence interval [CI], 1.29-1.51), preoperative opioid use (1-4 Rxs: IRR, 2.15; 95% CI, 1.85-2.51; ≥5u2009Rxs: IRR, 9.83; 95% CIu2009, 8.53-11.32), anxiety (IRR, 1.11; 95% CI, 1.03-1.20), opioid dependence (IRR, 1.23; 95% CI, 1.05-1.43), substance abuse (IRR, 1.17; 95% CI, 1.07-1.28), and general chronic pain (IRR, 1.38; 95% CI, 1.28-1.50).nnnCONCLUSIONnOpioid usage in patients undergoing SA is widespread at 1 year, with three-fourths of patients having been dispensed at least one Rx. These findings emphasize the need for surgeon and patient awareness as well as education in the management of postoperative opioid usage associated with the indicated conditions. Surgeons may consider these risk factors for preoperative risk stratification and targeted deployment of preventative strategies.

Is Anesthesia Technique Associated With a Higher Risk of Mortality or Complications Within 90 Days of Surgery for Geriatric Patients With Hip Fractures

Background Postoperative mortality and complications after geriatric hip fracture surgery remain high despite efforts to improve perioperative care for these patients. One factor of particular interest is anesthetic technique, but prior studies on this are limited by sample selection, competing risks, and incomplete followup. Questions/purposes (1) Among older patients undergoing surgery for hip fracture, does 90-day mortality differ depending on the type of anesthesia received? (2) Do 90-day emergency department returns and hospital readmissions differ based on anesthetic technique after geriatric hip fracture repairs? (3) Do 90-day Agency for Healthcare Research and Quality (AHRQ) outcomes differ according to anesthetic techniques used during hip fracture surgery? Methods We conducted a retrospective study on geriatric patients (65 years or older) with hip fractures between 2009 and 2014 using the Kaiser Permanente Hip Fracture Registry. A total of 1995 (11%) of the surgically treated patients with hip fracture were excluded as a result of missing anesthesia information. The final study sample consisted of 16,695 patients. Of these, 2027 (12%) died and 98 (< 1%) terminated membership during followup, which were handled as competing events and censoring events, respectively. Ninety-day mortality, emergency department returns, hospital readmission, deep vein thrombosis (DVT) or pulmonary embolism (PE), myocardial infarction (MI), and pneumonia were evaluated using multivariable competing risk proportional subdistribution hazard regression according to type of anesthesia technique: general anesthesia, regional anesthesia, or conversion from regional to general. Of the 16,695 patients, 58% (N = 9629) received general anesthesia, 40% (N = 6597) received regional anesthesia, and 2.8% (N = 469) patients were converted from regional to general. Results Compared with regional anesthesia, patients treated with general anesthesia had a higher likelihood of overall 90-day mortality (hazard ratio [HR], 1.22; 95% confidence interval [CI], 1.11-1.35; p < 0.001); however, when stratified by before and after hospital discharge but within 90 days of surgery, this higher risk was only observed during the inpatient stay (HR, 3.83; 95% CI, 3.18-4.61; p < 0.001); no difference was observed after hospital discharge (HR, 1.04; 95% CI, 0.94-1.16; p = 0.408). Patients undergoing conversion from regional to general also had a higher overall mortality risk compared with those undergoing regional anesthesia (HR, 1.34; 95% CI 1.04-1.74; p = 0.026), but this risk was only observed during their inpatient stay (HR, 6.84; 95% CI, 4.21-11.11; p < 0.001) when stratifying by before and after hospital discharge. Patients undergoing general anesthesia had a higher risk for all-cause readmission when compared with regional anesthesia (HR, 1.09; 95% CI, 1.01-1.19; p = 0.026). No differences according to anesthesia type were observed for risk of 90-day AHRQ outcomes, including DVT/PE, MI, and pneumonia. Conclusions We found the use of general anesthesia and conversion from regional to general anesthesia were associated with a higher risk of mortality during the in-hospital stay compared with regional anesthetic techniques, but this higher risk did not persist after hospital discharge. We also found general anesthesia to be associated with a higher risk of all-cause readmission compared with regional, but no other differences were observed in risk for complications. Our findings suggest regional anesthetic techniques may be preferred when possible in this patient population. Level of Evidence Level III, therapeutic study.

Risk of Infection After Allograft Anterior Cruciate Ligament Reconstruction: Are Nonprocessed Allografts More Likely to Get Infected? A Cohort Study of Over 10,000 Allografts:

Background: Allograft tissue is frequently used in anterior cruciate ligament reconstruction (ACLR). It is often irradiated and/or chemically processed to decrease the risk of disease transmission, but some tissue is aseptically harvested without further processing. Irradiated and chemically processed allograft tissue appears to have a higher risk of revision, but whether this processing decreases the risk of infection is not clear. Purpose: To determine the incidence of deep surgical site infection after ACLR with allograft in a large community-based sample and to evaluate the association of allograft processing and the risk of deep infection. Study Design: Cohort study; Level of evidence, 3. Methods: The authors conducted a cohort study using the Kaiser Permanente Anterior Cruciate Ligament Reconstruction Registry. Primary isolated unilateral ACLR with allograft were identified from February 1, 2005 to September 30, 2015. Ninety-day postoperative deep infections were identified via an electronic screening algorithm and then validated through chart review. Logistic regression was used to evaluate the likelihood of 90-day postoperative deep infection per allograft processing method: processed (graft treated chemically and/or irradiated) or nonprocessed (graft not irradiated or chemically processed). Results: Of 10,190 allograft cases, 8425 (82.7%) received a processed allograft, and 1765 (17.3%) received a nonprocessed allograft. There were 15 (0.15%) deep infections during the study period: 4 (26.7%) coagulase-negative Staphylococcus, 4 (26.7%) methicillin-sensitive Staphylococcus aureus, 1 (6.7%) Peptostreptococcus micros, and 6 (40.0%) with no growth. There was no difference in the likelihood for 90-day deep infection for processed versus nonprocessed allografts (odds ratio = 1.36, 95% CI = 0.31-6.04). Conclusion: The overall incidence of deep infection after ACLR with allograft tissue was very low (0.15%), suggesting that the methods currently employed by tissue banks to minimize the risk of infection are effective. In this cohort, no difference in the likelihood of infection between processed and nonprocessed allografts could be identified.

The Incidence of Subsequent Meniscal Surgery Is Higher in the Anterior Cruciate Ligament–Reconstructed Knee Than in the Contralateral Knee

Background: A goal of anterior cruciate ligament (ACL) reconstruction is to provide a meniscal protective effect for the knee. Purpose: (1) To evaluate whether there was a different likelihood of subsequent meniscal surgery in the ACL-reconstructed knee or in the normal contralateral knee and (2) to compare the risk factors associated with subsequent meniscal surgery in the ACL-reconstructed knee and contralateral knee. Study Design: Cohort study; Level of evidence, 3. Methods: Using an integrated health care system’s ACL reconstruction registry, patients undergoing primary ACL reconstruction, with no meniscal injury at the time of index surgery and a normal contralateral knee, were evaluated. Subsequent meniscal tears associated with ACL graft revision were excluded. Subsequent meniscal surgery in either knee was the outcome of interest. Sex, age, and graft type were assessed as potential risk factors. Survival analysis was used to compare meniscal surgery–free survival rates and to assess risk factors of subsequent meniscal surgery. Results: Of 4087 patients, there were 32 (0.78%) patients who underwent subsequent meniscal surgery in the index knee and 9 (0.22%) in the contralateral knee. The meniscal surgery–free survival rate at 4 years was 99.08% (95% CI, 98.64%-99.37%) in the index knee and 99.65% (95% CI, 99.31%-99.82%) in the contralateral knee. There was a 3.73 (95% CI, 1.73-8.04; P < .001) higher risk of subsequent meniscal surgery in the index knee compared with the contralateral knee, or a 0.57% absolute risk difference. After adjustments, allografts (hazard ratio [HR], 5.06; 95% CI, 1.80-14.23; P = .002) and hamstring autografts (HR, 3.11; 95% CI, 1.06-9.10; P = .038) were risk factors for subsequent meniscal surgery in the index knee compared with bone–patellar tendon–bone (BPTB) autografts. Conclusion: After ACL reconstruction, the overall risk of subsequent meniscal surgery was low. However, the relative risk of subsequent meniscal surgery in the ACL-reconstructed knee was higher compared with the contralateral knee. Only graft type was found to be a risk factor for subsequent meniscal surgery in the ACL-reconstructed knee, with a higher risk for allografts and hamstring autografts compared with BPTB autografts.

Do Obese and Extremely Obese Patients Lose Weight After Lumbar Spine Fusions?: Analysis of a Cohort of 7303 Patients From the Kaiser National Spine Registry

Mini The outcome of interest was ≥ 5% weight change 1 year postoperative from baseline. Seven thousand three hundred three lumbar fusions in the Kaiser Permanente Spine Registry between 2009 and 2013 were analyzed. Weight loss occurred in: body mass indexu200a<u200a30, 11.1%; obese, BMI 30 to 39, 16.6%, odds ratiou200a=u200a1.42; extremely obese, body mass index ≥40, 21.1%, odds ratiou200a=u200a1.73. Study Design. A retrospective cohort study from the Kaiser Permanente Spine Registry. Objective. The aim of this study was to determine whether obese and extremely obese patients with lumbar spine fusions lost a clinically significant amount of weight (≥5%) 1 year after their surgery. Summary of Background Data. Obesity in the United States has a prevalence of 35% and is a global health issue. Obesity is associated with lumbar spine disease. There is limited evidence regarding postsurgical weight loss after spine surgery. Methods. Adult patients in the Kaiser Permanente Spine Registry with lumbar fusions performed between 2009 and 2013 were included in the study sample (nu200a=u200a7303). The outcome of interest was ≥5% weight change 1 year postoperative from baseline. Three body mass index (BMI) groups were analyzed (BMIu200a<u200a30; 30–39 obese; ≥40 extremely obese). Covariate analysis, multivariable logistic regression, odds ratios (ORs), and 95% confidence intervals (95% CIs) are provided. Results. At the time of spine surgery, 4456 (61%) had a BMIu200a<u200a30, 2519 (34.5%) had a BMI between 30 and 39, 232 (3.2%) had a BMI ≥40, and 96 (1.3%) were missing their intraoperative BMI. We observed the following weight loss pattern: BMIu200a<u200a30, 11.1%; BMI 30 to 39, 16.6%; BMI ≥40, 21.1%. We observed the following weight gain pattern: BMIu200a<u200a30, 15.6%; BMI 30 to 39, 12.7%; BMI ≥40, 9.5%. After risk-adjustment, obese and extremely obese patients were more likely to lose a clinically significant amount of weight 1 year after surgery (BMI 30–39: ORu200a=u200a1.42, 95% CI 1.22–1.65; BMI ≥40: ORu200a=u200a1.73, 95% CI 1.21–2.47) compared with nonobese patients. Conclusion. In this large cohort of patients with lumbar spinal fusions, we observed more significant weight loss in obese and extremely obese patients than nonobese patients. Additional research is needed to determine whether this weight loss is due to improvements in back pain and increased physical activity. Level of Evidence: 3

Femoral Tunnel Drilling Method: Revision Risk After Anterior Cruciate Ligament Reconstruction

Objectives: The femoral tunnel in anterior cruciate ligament reconstruction (ACLR) can be created by the transtibial (TT) or tibial-independent (TI) methods. An anatomically located femoral tunnel can be more consistently achieved by TI methods, which include the medial portal (MP) and lateral (outside-in, retrodrill) techniques. Non-anatomic graft placement in ACLR may result in postoperative instability and meniscal or chondral pathology. An anatomically located graft may be subjected to higher postoperative physiologic forces than one placed non-anatomically. The purpose of this study was to examine isolated primary ACLR and determine the risk of aseptic revision based on femoral tunnel drilling method. Methods: A retrospective cohort study was conducted using an integrated U.S. healthcare system’s ACLR Registry to identify primary isolated unilateral cases from 2009 to 2014. Bilateral, double-bundle and multi-ligament reconstructions were excluded. Patients were divided into two groups based on femoral tunnel drilling method, TT or TI. Drilling method was evaluated as a risk factor for aseptic revision, with adjustment for age, sex, body mass index (BMI), race, and graft type using multivariable Cox proportional-hazards regression models. Results: 19,022 primary ACLR patients were included, of whom 6,991 (36.8%) were younger than 22 years old, 11,772 (61.9%) were male, 7,632 (40.1%) had a BMI < 25 kg/m2, 8,894 (46.8%) were White, and 7,403 (38.9%) received an allograft. There were 12,336 (64.9%) ACLRs performed using TI techniques (MP n=10,149, lateral n=2,187) and 6,686 (35.1%) using the TT method. Usage of TI approaches increased from 34% of all ACLR in 2009 to 84% in 2014. The cumulative reoperation probability at 5-year follow-up was lower in the TI group, 7.5% (95% CI 6.6-8.4), compared to the TT group, 8.2% (95% CI 7.4-9.1). After adjusting for the covariates, the cumulative failure probability at 5-year follow-up was higher in the TI group, 6.3% (95% CI 5.6-7.2), compared to the TT group, 5.0% (95% CI 4.3-5.7). [Figure 1] After adjusting for the covariates, the TI group had a higher risk for aseptic revision than the TT group (HR=1.4. 95% CI=1.1-1.7). Conclusion: In the largest known study of its type examining femoral tunnel drilling method for primary ACLR, after adjusting for age, sex, BMI, race and graft type, TI techniques were found to have a 1.4 times higher risk of revision than the TT method. Surgeons should be aware that ACLR grafts placed more anatomically by TI methods have a higher risk of revision, possibly due to higher postoperative physiologic graft forces experienced.

Risk of Revision for Various Hamstring Fixation Methods after ACLR

Objectives: Risk factors for anterior cruciate ligament reconstruction (ACLR) revision have included graft type, as well as fixation methods. Newer fixation techniques and devices for hamstring (HS) autograft have been introduced over the years. The purpose of this study was to compare the risk of aseptic revision after HS autograft ACLR between various femoral and tibial fixation methods/devices. Methods: Patients who underwent primary ACLR using a HS autograft from 2007-2014 were identified through a community-based registry for this retrospective cohort study. Bilateral, double bundle, and multiligament ACLRs were excluded. Patients were categorized (crosspin, interference, suspensory, or combination [more than one fixation]) based on the type of fixation utilized for the femur and tibia. Femoral/tibial fixation groupings with more than 500 patients were evaluated as a risk factor for aseptic revision, with adjustment for age, sex, body mass index, and race/ethnicity, using a multivariable Cox proportional-hazards regression model. Results: 6,716 primary ACLR patients were included, of whom 2,894 (38.8%) were younger than 22 years old, 4,111 (61.2%) were male, 2,956 (44.0%) had a BMI < 25 kg/m2, and 3,163 (47.1%) were caucasian. Five femoral/tibial groupings had more than 500 patients: suspensory/interference (n=2,176, 32.4%), suspensory/combination (n=1,940, 28.9%), interference/combination (n=1,025, 15.3%), interference/interference (n=845, 12.6%), and crosspin/combination (n=730, 10.9%). The cumulative failure probability at 5 years was highest for the suspensory/interference group (9.0%, 95% CI 7.2-11.2), followed by suspensory/combination (6.7%, 95% CI 5.4-8.4), interference/interference (5.1%, 95% CI 3.7-7.2), interference/combination (4.3%, 95% CI 2.9-6.3), and crosspin/combination (3.1%, 95% CI 2.0-4.9). After adjusting for the other covariates, the hazard ratio for aseptic revision was 2.9 (95% CI 1.9-4.7) for the suspensory/interference group, 2.7 (95% CI 1.7-4.5) for the suspensory/combination group, 1.6 (95% CI 0.9-3.0) for the interference/combination group, and 2.1 (95% CI 1.2-3.7) for the interference/interference group when compared to the crosspin/combination group. Conclusion: ACLR using HS autograft appears to have the highest risk of aseptic revision when suspensory fixation is used on the femoral side and is coupled with either an interference screw or combination fixation on the tibial side. Understanding the device-related risk of aseptic revision after HS autograft ACLR will help guide surgeons regarding which devices may negatively influence surgical outcomes.