Abnormal Coagulation as a Risk Factor for Postoperative Complications After Primary and Revision Total Hip and Total Knee Arthroplasty.

BACKGROUND: Patients undergoing total joint arthroplasty (TJA) have an increased likelihood of having an abnormal coagulation profile compared with the general population. Coagulation abnormalities are often screened for before surgery and considered during perioperative planning. This study assesses a preoperative abnormal coagulation profile as a risk factor for postoperative complications after total hip arthroplasty (THA), revision THA (rTHA), total knee arthroplasty (TKA), and revision TKA (rTKA) and then examines specific coagulopathies to determine their influence on complication rates. METHODS: Patients who underwent THA, rTHA, TKA, or rTKA from 2011 to 2017 were identified in the American College of Surgeons National Surgical Quality Improvement Program database and then assessed for preoperative abnormal coagulation profiles. Various postoperative complications were analyzed for each cohort, and two separate multivariate regression analyses were used to assess the relationship between abnormal coagulation and postoperative complications. RESULTS: 403,566 THA, rTHA, TKA, or rTKA cases were identified, and 40,466 (10.0%) of patients were found to have an abnormal coagulation profile. Patients with preoperative coagulation abnormalities had higher likelihoods of postoperative complications after primary TJA than in revision TJA. An international normalized ratio>1.2 was associated with the most types of postoperative complications, followed by a bleeding disorder diagnosis. A partial thromboplastin time>35 seconds was associated with only one type of postoperative complication, while a platelet count <150,000 per µL was associated with postoperative complications only after TKA. CONCLUSION: TJA in patients with abnormal coagulation profiles may result in adverse outcomes. These patients may benefit from preoperative intervention. Prophylactic care needs to be personalized to the specific coagulation abnormalities present.

Histological Assessment of Wallerian Degeneration of the Rat Tibial Nerve Following Crush and Transection Injuries.

BACKGROUND: Wallerian degeneration (WD) following peripheral nerve injury (PNI) is an area of growing focus for pharmacological developments. Clinically, WD presents challenges in achieving full functional recovery following PNI, as prolonged denervation of distal tissues for an extended period of time can irreversibly destabilize sensory and motor targets with secondary tissue atrophy. Our objective is to improve upon histological assessments of WD. METHODS: Conventional methods utilize a qualitative system simply describing the presence or absence of WD in nerve fibers. We propose a three-category assessment that allows more quantification: A fibers appear normal, B fibers have moderate WD (altered axoplasm), and C fibers have extensive WD (myelin figures). Analysis was by light microscopy (LM) on semithin sections stained with toluidine blue in three rat tibial nerve lesion models (crush, partial transection, and complete transection) at 5 days postop and 5 mm distal to the injury site. The LM criteria were verified at the ultrastructural level. This early outcome measure was compared with the loss of extensor postural thrust and the absence of muscle atrophy. RESULTS: The results showed good to excellent internal consistency among counters, demonstrating a significant difference between the crush and transection lesion models. A significant decrease in fiber density in the injured nerves due to inflammation/edema was observed. The growth cones of regenerating axons were evident in the crush lesion group. CONCLUSION: The ABC method of histological assessment is a consistent and reliable method that will be useful to quantify the effects of different interventions on the WD process.

A Retrospective Comparative Analysis of Perioperative Complications in Navigated versus Conventional Thoracolumbar Fusion in the Setting of Adult Spinal Deformity.

OBJECTIVE: Stereotactic intraoperative computer-assisted navigation has been shown to improve pedicle screw accuracy in spinal fusion surgery, but evidence of impact of navigation on clinical outcomes is lacking. The aim of this study is to compare rates of perioperative complications between navigated and nonnavigated procedures for deformity correction. METHODS: An administrative database was queried for adult patients undergoing thoracolumbar fusion procedures for deformity. Nonelective cases and those involving malignancy, infection, or trauma were excluded. Individuals were divided into 2 cohorts based on the use of stereotactic intraoperative navigation and paired 1:1 for comparison based on a propensity score matching algorithm. Rates of unplanned reoperation and other perioperative complications were compared between matched groups. A multivariable Cox regression model was constructed to identify the impact of navigation on specific subgroups. RESULTS: A total of 6150 patients met eligibility criteria for the study; after propensity score matching, 456 patients who underwent conventional fusion were matched to 456 patients receiving intraoperative navigation. Navigated cases took an average of 30 minutes longer than nonnavigated cases. There were no significant differences in rates of complications between cohorts. A subgroup analysis revealed that use of navigation was associated with decreased hazard for reoperation in individuals undergoing interbody fusion. CONCLUSIONS: Despite increased surgical duration, the use of navigation does not seem to significantly impact rates of perioperative complications outside of procedures involving interbody fusion. Surgeons should elect to use navigation in cases expected to be of high operative complexity at their own discretion.

Impact of Body Mass Index on Postsurgical Outcomes for Workers' Compensation Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion.

BACKGROUND: Increased morbidity associated with obesity imposes a greater financial burden on companies that provide insurance to their employees. Few studies have investigated the relationship between body mass index (BMI) and patient-reported outcome measures (PROMs) for minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) in the workers' compensation (WC) population. METHODS: WC patients who underwent a primary, single-level MIS TLIF were included/grouped according to BMI: nonobese (<30 kg/m2); obese I (≥30, <35 kg/m2); severe + morbid (≥35). PROMs were collected pre- and postoperatively: visual analog scale (VAS), Oswestry Disability Index (ODI), 12-Item Short Form (SF-12) physical composite score (PCS), and Patient-Reported Outcome Measurement Information System physical function (PROMIS-PF). BMI predictive power grouping on PROMs was evaluated using simple linear regression. Established minimum clinically important difference values were used to compute achievement rates across PROMs using logistic regression. RESULTS: A total of 116 nonobese, 70 obese I, and 61 severe + morbid patients were included. Demographics among BMI grouping significantly differed in gender, hypertensive status, and American Society of Anesthesiologists score (P ≤ 0.037, all). Operative time was significantly different in perioperative values among BMI grouping (P ≤ 0.001). Increased BMI was significantly associated with greater VAS back at 12 weeks and 2 years (P ≤ 0.026, all), greater ODI preoperatively at 12 weeks and 6 months (P ≤ 0.015, all), and decreased PROMIS-PF at 12 weeks (P ≤ 0.011, all). Mean PROMs between obese I and severe + morbid cohorts differed in SF-12 PCS at 12 weeks, only (P = 0.050). ODI overall was the only parameter for which minimum clinically important difference was achieved among BMI cohorts (P ≤ 0.023). CONCLUSION: WC patients with increased BMI were more likely to develop significant back pain and disability at numerous postoperative timepoints compared with nonobese individuals. Our findings highlight the weight management importance within WC population to minimize back pain and disability following MIS TLIF, but provide a sense of reassurance with comparable clinical improvement regardless of BMI. CLINICAL RELEVANCE: When considering the effect of weight, surgeons may incorporate these findings in managing patient expectations in the WC population undergoing lumbar spine surgery.

Predictors of Extended Hospitalization and Early Reoperation After Elective Lumbar Disc Arthroplasty.

BACKGROUND: Lumbar disc arthroplasty (LDA) has emerged as a motion-sparing alternative to lumbar fusion. Although LDA may be amenable to the ambulatory surgical setting, to date no study has identified the factors predisposing patients to extended hospital stay. METHODS: A national surgical quality improvement database was queried from 2011 to 2019 for patients undergoing elective, single-level, primary LDA. Univariate and multivariate logistic regression analyses were performed to elucidate predictors of length of stay (LOS) at or above the 90th percentile of the study population (3 days). Secondary study endpoints included rates of complications, as well as predictors and reasons for unplanned reoperation within 30 days. RESULTS: A total of 630 patients met eligibility criteria for the study, of whom 517 (82.1%) had LOS <3 days and 113 (17.9%) had LOS ≥3 days. Multivariate logistic regression revealed associations between prolonged hospitalization and postoperative diagnosis of degenerative disk disease, obesity, Hispanic identity, and operation length >120 minutes. Before discharge, patients with LOS ≥3 days were more likely to have venous thromboembolisms, pneumonia, surgical site infections, and reoperations. Independent predictors of reoperation were wound infections, diabetes, and smoking. CONCLUSIONS: Complications following elective single-level LDA are relatively rare, with few extended hospitalizations being attributable to any specific complication. Risk factors for prolonged LOS appear to be related to diagnosis and surgical time rather than to modifiable preoperative comorbidities. Conversely, unplanned reoperations within 30 days are associated with optimizable perioperative factors such as smoking, diabetes, and surgical site infection.

Enterobacter cloacae Periprosthetic Joint Infection After Bariatric Surgical Anastomotic Leak.

Four weeks after a bilateral total knee arthroplasty (TKA), an immunocompetent, 61-year-old, Caucasian man presented with a periprosthetic joint infection (PJI) of the left knee by Enterobacter cloacae (an enteric bacteria). The most likely source of his infection was due to an anastomotic leak after a bariatric surgery done 6 months before TKA. There is a growing focus on stratifying the risk of PJI after TKA. Hematogenous seeding of enteric bacteria leading to PJI is an unexplored risk that will become more prevalent as bariatric procedures before TKA continue to increase in frequency. We present a patient who demonstrates this PJI risk with a rare microbe (E cloacae).