Andrew Chung

University of Southern California | USC · Department of Orthopaedic Surgery

Lumbosacral spinal pathologies are not uncommon and include trauma, malignancy, infection, and degenerative disease. The primary diagnostic imaging modalities used to evaluate the lumbosacral spine include plain-film radiographs, magnetic resonance imaging, and computed tomography (CT).Compared to plain radiography and magnetic resonance imaging (M...

Background: To analyze gender differences regarding the recovery experience (pain, function, complications) after spinal arthrodesis surgery. Methods: Pre-operative and post-operative gender-based differences in patient-reported outcomes for open posterior spinal arthrodesis at 6 weeks, 3 months, 6 months, and 1 year were studied, including age,...

Study design: Retrospective review of prospectively collected data. Objective: To determine if the addition of L5-S1 interbody support in long fusion deformity constructs is associated with superior long-term clinical and radiographic outcomes. To compare the 5-year clinical and radiographic outcomes and complications between long fusion constru...

Study design: Retrospective Cohort Study OBJECTIVE.: To evaluate the safety of 2-level cervical disc replacement (CDR) in the outpatient setting. Summary of background data: Despite growing interest in CDR, limited data exists evaluating the safety of 2-level CDR in the outpatient setting. Methods: The National Surgical Quality Improvement Pro...

Introduction Interscalene brachial plexus blocks are a common modality utilized to provide adjunctive pain relief with shoulder replacement surgery. In 2018 the Federal Drug Administration approved the use liposomal bupivacaine (LB) for such nerve blocks. We sought to evaluate whether this formulation of bupivacaine would provide superior pain reli...

In conjunction with neurofibromas, schwannomas are the 2nd most commonly occurring intradural extramedullary tumor. They are a benign encapsulated nerve sheath tumor that are typically slow growing. They occur equally as frequently in the cervical and lumbar spine. If symptomatic, surgical resection may be warranted. In this surgical technique vide...

Study design: Review. Objective: A comparative overview of cost-effectiveness between minimally invasive versus and equivalent open spinal surgeries. Methods: A literature search using PubMed was performed to identify articles of interest. To maximize the capture of studies in our initial search, we combined variants of the terms "cost," "mini...

Study design: Systematic review. Objectives: To systematically review, critically appraise and synthesize evidence on use of stem cells from autologous stem cells from bone marrow aspirate, adipose, or any other autologous sources for fusion in the cervical spine compared with other graft materials. Methods: A systematic search of PubMed/MEDLI...

Purpose of review: To provide information on characteristics and use of various ceramics in spine fusion and future directions. Recent findings: In most recent years, focus has been shifted to the use of ceramics in minimally invasive surgeries or implementation of nanostructured surface modification features to promote osteoinductive properties...

Study designRetrospective study of a prospectively collected database at one center.Objectives Assess the outcomes and complications of adult spinal deformity (ASD) surgery in patients that are 75 years and older compared with patients of 65–75 years of age.Summary of background dataWith increasing amounts of ASD surgery being performed on elderly...

Study Design Retrospective cohort study. Objective To determine if local administration of liposomal bupivacaine (LB) reduces postoperative pain scores and narcotic use in spinal deformity patients. Methods Adult patients undergoing elective spinal fusion (7 or more levels) for scoliosis or kyphosis were selected for inclusion. Patients received...

With the health-care environment becoming increasingly patient centric and cost-conscious, interest levels in spinal endoscopy are at an all-time high. Patient demand for the least invasive procedures combined with surgeon desire to maximally shorten the post-operative recovery period have further driven this surgical evolution. Mounting scientific...

Background: Anterior cervical discectomy and fusion (ACDF) is well-tolerated by most patients and commonly necessitates only a short hospital admission. Surgical delay after hospital admission, however, may result in longer hospital stays, consequently increasing hospital resource utilization. The current study evaluates risk factors for surgical...

Study Design Retrospective review. Objectives (1) Identify the 90-day rate of readmission following revision lumbar fusion, (2) identify independent risk factors associated with increased rates of readmission within 90 days, (3) and identify the hospital costs associated with revision lumbar fusion and subsequent readmission within 90 days. Metho...

Background: Within the emergency department (ED) setting, anterior cruciate ligament (ACL) rupture is commonly misdiagnosed, leading to improper treatment and potential meniscal injury and total joint replacement. Utilizing traditional clinical tests to diagnosis ACL rupture leads to the correct diagnosis in about 30% of cases. The lever sign is a...

Study Design Retrospective cohort study. Objective To evaluate inpatient outcomes in dialysis dependent patients undergoing elective cervical spine surgery. Methods A total of 1605 dialysis dependent patients undergoing elective primary or revision cervical spine surgery for degenerative conditions were identified from the National Inpatient samp...

Osteolysis of the patella following total knee arthroplasty is both uncommon and poorly described in the literature. We describe 3 cases of total knee arthroplasty with patella resurfacing that later presented with anterior knee pain with patellar osteolysis without evidence of patellar implant failure: 2 males and 1 female patient, all with bilate...

Background Lumbar spine injuries (LSIs) are common in both men’s and women’s National Collegiate Athletic Association (NCAA) basketball players and can frequently lead to reinjuries and persistent pain. Purpose To describe the epidemiology of an LSI in collegiate men’s and women’s basketball during the 2009-2010 through 2013-2014 academic years....

BACKGROUND CONTEXT Some studies identify complications associated with off-label use of rhBMP-2 in the setting of transforaminal lumbar interbody fusion (TLIF). The dose-related efficacy of rhBMP-2 in the setting of short segment fusion has not been thoroughly investigated. PURPOSE In the setting of short-segment thoracolumbar fusion augmented wit...

Background National Collegiate Athletic Association (NCAA) football players are at a high risk of injuries. Elbow injuries are uncommon, but there are insufficient data specifically on elbow injuries sustained in NCAA football players. Purpose To define the epidemiology of elbow injuries in NCAA football players during the 2009-2010 to 2013-2014 s...

Background The number of total shoulder arthroplasty (TSA) procedures performed annually is increasing as a result of an aging population and an increased access to subspecialty-trained upper extremity arthroplasty surgeons. An up-to-date analysis of the incidence of, risk factors for, and reasons for 90-day readmissions in primary anatomic TSA has...

Background Little research has focused on the rates and patterns of elbow injuries in National Collegiate Athletic Association (NCAA) student-athletes. Purpose To describe the epidemiological patterns of elbow injuries in NCAA athletes during 5 seasons over the academic years 2009 through 2014 using the NCAA Injury Surveillance Program (NCAA-ISP)...

Study design: Descriptive epidemiology study. Objective: The purpose of this study was to describe the epidemiology of neck and cervical spine injuries in collegiate athletes over a 5-year period. Summary of background data: The incidence and etiology of neck and cervical spine injuries in National Collegiate Athletic Association (NCAA) athlet...

Background: Lumbar spine injuries (LSI) are common in both men’s and women’s National College Athletic Association (NCAA) basketball players and can frequently lead to re-injury and persistent pain. Purpose: The purpose of this study was to describe the epidemiology of LSI in collegiate men’s and women’s basketball during the 2009/2010-2013/2014...

Background: Superior capsular reconstruction (SCR) has recently been proposed as a surgical solution to the irreparable rotator cuff tear and has gained popularity due to promising early results. Therefore, the purpose of this study is to review the biomechanical and clinical outcomes in shoulders with this condition treated with SCR. Methods: A s...

Study design: Retrospective cohort study. Objective: Evaluate the trends in management and inpatient outcomes in patients with syndromic scoliosis undergoing spinal deformity correction. Summary of background data: Syndromic scoliosis (SS) refers to scoliosis that is most commonly associated with systemic disease including Ehler Danhlos syndro...

Background: There has been a surge in interest with regard to the utility of liposomal bupivacaine as part of a perioperative pain management protocol. The current study was proposed to critically assess the efficacy of liposomal bupivacaine as a local anesthetic for pain relief following orthopaedic procedures. Methods: A systematic review of p...

Study design: A retrospective cohort study. Objective: The aim of this study was to evaluate the effect of preoperative dehydration on hospital length of stay (LOS), rates of 30-day postoperative complications, related reoperations, and readmissions. Summary of background data: Preoperative dehydration has long been associated with postoperati...

Background: Low back injuries are common in collegiate football players and can frequently lead to persistent pain, reinjuries, and time lost from participation. Purpose: To describe the epidemiology of back injuries in National Collegiate Athletic Association (NCAA) football players during the 2009/2010 through 2013/2014 academic years utilizin...

Background An adequate characterization of 90-day readmissions after primary reverse total shoulder arthroplasty (RTSA) on a national level remains to be undertaken. As bundled payment models become more prevalent, an improved understanding of readmission data will help to predict resource utilization and expenses. Methods All adult patients who u...

Study design: Descriptive epidemiology study. Objective: The purpose of this study was to describe the epidemiology of cervical spine injuries in collegiate football players. Summary of background data: The incidence and etiology of cervical spine injuries in National Collegiate Athletic Association (NCAA) football players has not been well de...

MINI: With the increasing popularity of bundled payment models in spine, defining the 90-day post-operative course is of paramount importance. Using the National Readmissions Database (NRD), we identified predictors of 90-day readmission and defined the cost associated with readmission after elective primary lumbar spine surgery in the inpatient se...

Background: Historically, infection control rates with debridement and component retention have been poor in the management of acute prosthetic joint infections. We previously described a 2-stage debridement with prosthesis retention protocol for acute periprosthetic joint infection and reported a 90% success rate in a sample of 20 patients. Meth...

Background Lumbar spine injuries in National Collegiate Athletic Association (NCAA) athletes have not been well studied. Purpose To describe the epidemiology of lumbar spine injuries in NCAA athletes during the 2009/2010 through 2014/2015 academic years utilizing the NCAA Injury Surveillance Program (ISP). Study Design Descriptive epidemiology st...

Background: Malnutrition has been associated with increased perioperative morbidity and mortality in orthopedic surgery. This study was designed with the hypothesis that preoperative hypoalbuminemia, a marker for malnutrition, is associated with increased complications after hand surgery. Methods: A retrospective cohort study of 208 hand-specific C...

Low back and neck pain are among the top contributors for years lived with disability, causing patients to seek substantial non-operative and operative care. Intervertebral disc herniation is one of the most common spinal pathologies leading to low back pain. Patient comorbidities and other risk factors contribute to the onset and magnitude of disc...

Background: The minimum clinically important difference (MCID) attempts to define the patient's experience of treatment outcomes. Efforts at calculating the MCID have yielded multiple and inconsistent MCID values. The purposes of this review were to describe the usage of the MCID in the most recent orthopaedic literature, to explain the limitation...

Background: The minimum clinically important difference (MCID) attempts to define the patient's experience of treatment outcomes. Efforts at calculating the MCID have yielded multiple and inconsistent MCID values. The purposes of this review were to describe the usage of the MCID in the most recent orthopaedic literature, to explain the limitation...

Objectives: The goal of the present study is to evaluate the association between timing of hip fracture surgery with post-operative length of stay and outcomes. Design: Retrospective review utilizing the American College of Surgeon's National Surgical Quality Improvement Program (NSQIP) database. Setting: National inquiry database incorporatin...

In patients undergoing surgery, optimal pain management is associated with improved perioperative outcomes, patient satisfaction with surgery, and a more rapid functional recovery. In recent years, the employment of multimodal pain management strategies has become increasingly widespread. In particular, there has been an explosion in the use of per...

BACKGROUND CONTEXT Up to 68% of the elderly population has spinal deformity which is a growing concern given that average lifespan is increasing. Adult spinal deformity surgeries are generally very taxing and come with significant morbidity. It is of interest to see how adult spinal surgery outcomes compare between the age groups of 65-74.9 and 75+...

BACKGROUND CONTEXT Increasing public awareness of the dangers of narcotics use has prompted recent government legislation aimed at curtailing the "opioid crisis." Many of these new regulations are placing greater restrictions on the ability of physicians to prescribe narcotics with some laws penalizing surgeons for excessive utilization. Liposomal...

Purpose: Avoidance of postoperative complications is important to both patients and surgeons. In an attempt to optimize postoperative outcomes, a risk stratification scoring system has been created to aid in optimizing risk factors for general surgical complications in hand surgery patients. Methods: Patients were identified who underwent hand p...

Study Design Retrospective cohort study. Objectives Epidemiologic studies suggest that the prevalence of moderate to severe obstructive sleep apnea (OSA) is increasing. OSA has been linked to increased rates of postoperative complications following surgery. Large studies, however, regarding surgical outcomes in this patient population, particularl...

Objectives: Low serum albumin levels (hypoalbuminemia) have classically been used to identify malnutrition. The effect of increasing severity of malnutrition on postoperative outcomes in patients undergoing hip fracture surgery has not been well delineated on a large scale. Design: Retrospective. Setting: Multicenter. Patient/participants: A...

Category Trauma Introduction/Purpose Pre-operative serum albumin levels have routinely been utilized to assess nutritional status. Malnutrition, as defined by serum albumin levels < 3.5 g/dL, has been associated with worse post-operative outcomes in multiple surgical settings. The effect of hypo-albuminemia on 30-day post-operative outcomes after...

Study design: Retrospective cohort study OBJECTIVE.: To evaluate the effect of MetS on 30-day morbidity and mortality following elective lumbar spinal fusion SUMMARY OF BACKGROUND DATA.: Metabolic syndrome (MetS) is a variable combination of hypertension, obesity, elevated fasting plasma glucose, and dyslipidemia.MetS has been associated with an i...

Study design: . Retrospective cohort study OBJECTIVE.: To evaluate hospital outcomes in dialysis dependent patients undergoing elective lumbar surgeries. Summary of background data: Due to their overall poor health status and concomitant comorbidity burden, spinal surgery in dialysis dependent patients represents a significant challenge to spine...

Purpose: There is a recent trend toward performing most hand surgery procedures under local and/or regional anesthesia without sedation. However, little evidence exists regarding the postoperative complications associated with local/regional anesthesia without sedation, especially compared with local/regional anesthesia with sedation or general an...

Study design: Review of the 2011-2015 minimum clinically important difference (MCID)-related publications in Spine, Spine Journal, Journal of Neurosurgery-Spine, and European Spine Journal. Objective: To summarize the various determinations of MCID and to analyze its usage in the spine literature of the past 5 years in order to develop a basic r...

Purpose: The clinical decision to replant an amputated digit is driven primarily by surgical indication. However, the extent to which patient comorbidity should play into this decision is less well defined. This study was designed to determine the effect of patient comorbidities on the success, risk, and cost of digital replantation. Methods: Al...