Scholars@Duke
Robert Lark

Robert Lark

Professor of Orthopaedic Surgery
Orthopaedic Surgery
lark0002@mc.duke.edu
DUMC Box 2809, 3000 Erwin Road, Durham, NC 27710
209 Lenox Baker Children's Hospital, Durham, NC 27705
Office hours Monday-Friday 8:00-4:30  

Selected Publications

Providing Beyond Clinic Hours: A Single-center Analysis of Patient Portal Communication in Pediatric Orthopaedic Care.

Journal Article J Pediatr Soc North Am · February 2026 BACKGROUND: Patient portals are an increasingly common tool for patient-provider communication not only improving access for patients but also creating a significant workload for providers. However, their utilization in pediatric orthopaedics remains uncle ... Full text Link to item Cite

Barriers to early detection: the impact of healthcare access and screening on conservative treatment opportunities in adolescent idiopathic scoliosis.

Journal Article Spine Deform · November 17, 2025 INTRODUCTION: Prior to surgical intervention for adolescent idiopathic scoliosis (AIS), patients with mild-to-moderate deformity and skeletal growth remaining can be treated conservatively after referral to specialists. Healthcare access may influence scre ... Full text Link to item Cite

High Preoperative Body Mass Index Is Associated With Implant Breakage in Patients Treated With Magnetically Controlled Growing Rods for Early-onset Scoliosis.

Journal Article J Pediatr Orthop · September 1, 2025 INTRODUCTION: Magnetically controlled growing rods (MCGRs) have become the current standard in the growth-friendly treatment of patients with early-onset scoliosis (EOS). MCGRs allow noninvasive lengthenings with external lengthening device and reduce the ... Full text Link to item Cite

How Does the Vertical Expandable Prosthetic Titanium Rib Lengthening Intervals Affect the Clinical Outcome in Early Onset Scoliosis Patients? A Five-Year Follow-Up Study.

Journal Article J Pediatr Orthop · August 1, 2025 BACKGROUND: Untreated early-onset scoliosis (EOS) is often complicated by decreased thoracic expansion growth and pulmonary complications. Various fusion-less techniques have been developed to address these complications, including growing rods and vertica ... Full text Link to item Cite

Outcomes of Growth-Friendly Surgical Treatment of Early Onset Scoliosis in Children With Prune Belly Syndrome: A Preliminary Report.

Journal Article J Pediatr Orthop · April 1, 2025 BACKGROUND: Prune belly syndrome (PBS) is a rare condition characterized by absence of abdominal musculature, cryptorchidism, and obstructive uropathy. The most common orthopaedic problem is scoliosis, yet no reports on growth-friendly surgical treatment o ... Full text Link to item Cite

Reanalysis of RNA sequencing data ends diagnostic odyssey and expands the phenotypic spectrum of congenital titinopathy.

Journal Article Am J Med Genet A · November 2024 Although next-generation sequencing has enabled diagnoses for many patients with Mendelian disorders, the majority remain undiagnosed. Here, we present a sibling pair who were clinically diagnosed with Escobar syndrome, however targeted gene testing was ne ... Full text Link to item Cite

Current Concepts in the Treatment of Early Onset Scoliosis

Journal Article Journal of Clinical Medicine · August 1, 2024 Despite many surgical advances in the treatment of early onset scoliosis (EOS) over the past two decades, this condition remains a challenge to address. While otherwise healthy children can have EOS, many of these patients have complicated comorbidities ma ... Full text Cite

Predicting 3D forearm fracture angle from biplanar Xray images with rotational bone pose estimation

Conference Proceedings of Machine Learning Research · January 1, 2024 Two-dimensional X-ray images, while widely used, have limitations to reflect 3D information of the imaged objects. Several studies have tried to recover such information from multiple X-ray images of the same object. Still, those approaches often fail due ... Cite

Preoperative left shoulder elevation > 1 cm is predictive of severe postoperative shoulder imbalance in early onset idiopathic scoliosis patients treated with growth-friendly instrumentation.

Journal Article Spine Deform · September 2023 PURPOSE: Prior research has demonstrated the influence of preoperative shoulder elevation (SE), proximal thoracic curve magnitude, and upper instrumented vertebra (UIV) on shoulder balance after PSF for AIS. Our purpose was to evaluate the impact of these ... Full text Link to item Cite

Low radius of curvature growth-friendly rib-based implants increase the risk of developing clinically significant proximal junctional kyphosis.

Journal Article Spine Deform · May 2023 BACKGROUND: Clinically significant proximal junctional kyphosis (PJK) occurs in 20% of children with scoliosis treated with posterior distraction-based growth-friendly surgery. In an effort to identify modifiable risk factors, it has been theorized biomech ... Full text Link to item Cite

Lengthening Behavior of Magnetically Controlled Growing Rods in Early-Onset Scoliosis: A Multicenter Study.

Journal Article J Bone Joint Surg Am · December 21, 2022 BACKGROUND: The "law of diminishing returns" is described for traditional growing rods. Magnetically controlled growing rods (MCGRs) have become a preferred implant for the surgical treatment of early-onset scoliosis (EOS). We examined a large cohort of pa ... Full text Link to item Cite

Does the presence of programmable implanted devices in patients with early onset scoliosis alter typical operative and postoperative practices? A survey of spine surgeons.

Journal Article Spine Deform · July 2022 PURPOSE: Operative and postoperative management of early onset scoliosis (EOS) patients with programmable implanted devices has not been well characterized in the literature. The aim of this study was to describe current practices for pediatric spine surge ... Full text Link to item Cite

To tether or fuse? Significant equipoise remains in treatment recommendations for idiopathic scoliosis.

Journal Article Spine Deform · July 2022 PURPOSE: Vertebral body tethering (VBT) continues to grow in interest from both a patient and surgeon perspective for the treatment of scoliosis. However, the data are limited when it comes to surgeon selection of both procedure type and instrumented level ... Full text Link to item Cite

Body mass index affects outcomes after vertebral body tethering surgery.

Journal Article Spine Deform · May 2022 PURPOSE: To compare the outcomes of anterior Vertebral Body Tethering (AVBT) surgery between overweight and non-overweight patients. METHODS: AIS/JIS patients with AVBT with 2-year follow-up from a multi-center pediatric spine database were evaluated pre-o ... Full text Link to item Cite

Shared Decision-Making for Juvenile Scoliosis.

Journal Article Pediatrics · April 1, 2022 Full text Link to item Cite

Preoperative optimization and nutrition

Chapter · February 3, 2022 Due to the complexity and frequency of comorbidities associated with early onset scoliosis, preoperative optimization is mandatory to prepare patients and families for casting and/or surgical intervention. Multidisciplinary collaboration across several spe ... Full text Cite

The Effect of Surgeon Experience on Outcomes Following Growth Friendly Instrumentation for Early Onset Scoliosis.

Journal Article J Pediatr Orthop · February 1, 2022 BACKGROUND: The purpose of this study was to utilize a multicenter, multisurgeon cohort to assess the effect of surgeon experience on outcomes of growth friendly instrumentation (GFI) in early onset scoliosis (EOS). We hypothesized that unplanned return to ... Full text Link to item Cite

Outcomes and Complications in Management of Congenital Myopathy Early-Onset Scoliosis.

Journal Article J Pediatr Orthop · October 1, 2021 BACKGROUND: Congenital myopathies (CMs) are complex conditions often associated with early-onset scoliosis (EOS). The purpose of this study was to investigate radiographic outcomes in CM patients undergoing EOS instrumentation as well as complications. Sec ... Full text Link to item Cite

Implant Distribution Versus Implant Density in Lenke Type 1 Adolescent Idiopathic Scoliosis: Does the Position of the Screw Matter?

Journal Article Global Spine J · September 2021 Featured Publication STUDY DESIGN: Retrospective study. OBJECTIVE: Previous studies have demonstrated that increased implant density (ID) results in improved coronal deformity correction. However, low-density constructs with strategically placed fixation points may achieve sim ... Full text Link to item Cite

The role of traditional growing rods in the era of magnetically controlled growing rods for the treatment of early-onset scoliosis.

Journal Article Spine deformity · September 2021 PurposeTo describe the clinical and radiographic profile of early-onset scoliosis (EOS) patients treated with traditional growing rods (TGR) during the magnetically-controlled growing rod (MCGR) era.MethodsA US multicenter EOS database wa ... Full text Cite

Growth Modulation by Stimulating the Growth Plate: A Pilot Study.

Journal Article Ultrasound Med Biol · August 2021 This study investigates the ability of low-intensity pulsed ultrasound (LIPUS) or direct injection of recombinant growth hormone (rGH) to stimulate local growth of long bones. In a randomized controlled animal trial, healthy immature rabbits were allocated ... Full text Link to item Cite

Image quality of EOS low-dose radiography in comparison with conventional radiography for assessment of ventriculoperitoneal shunt integrity.

Journal Article J Neurosurg Pediatr · April 1, 2021 OBJECTIVE: Patients with shunted hydrocephalus often accumulate high levels of radiation over their lifetimes during evaluation of hardware integrity. Current practice involves the use of a series of conventional radiographs for this purpose. Newer low-dos ... Full text Link to item Cite

Impact of growth friendly interventions on spine and pulmonary outcomes of patients with spinal muscular atrophy.

Journal Article Eur Spine J · March 2021 Featured Publication PURPOSE: Patients with spinal muscular atrophy (SMA) are often treated with growth friendly devices such as vertical expandable prosthetic titanium rib(VEPTR) and magnetically controlled growing rods(MCGR) to correct spinal deformity and improve pulmonary ... Full text Link to item Cite

Growth-friendly Spinal Instrumentation in Marfan Syndrome Achieves Sustained Gains in Thoracic Height Amidst High Rates of Implant Failure.

Journal Article J Pediatr Orthop · March 1, 2021 BACKGROUND: There are few reports on the surgical management of early-onset scoliosis (EOS) associated with Marfan syndrome (MFS). Affected patients tend to have more rapid curve progression than those with idiopathic EOS, and their course is further compl ... Full text Link to item Cite

Congenital Scoliosis of the Pediatric Cervical Spine: Characterization of a 17-Patient Operative Cohort.

Journal Article J Pediatr Orthop · March 1, 2021 BACKGROUND: Congenital cervical scoliosis is rare, and there is a paucity of literature describing surgical outcomes. We report surgical outcomes in a 17-patient cohort with surgical correction for congenital cervical scoliosis and identify risk factors as ... Full text Link to item Cite

Risk Factors Associated With Infection in Open Fractures of the Upper and Lower Extremities.

Journal Article J Am Acad Orthop Surg Glob Res Rev · December 8, 2020 INTRODUCTION: Open fractures are associated with a high risk of infection. The prevention of infection is the single most important goal, influencing perioperative care of patients with open fractures. Using data from 2,500 participants with open fracture ... Full text Link to item Cite

Staying ahead of the curve: the use of spinopelvic parameters to predict curve progression and bracing success in adolescent idiopathic scoliosis.

Journal Article Spine Deform · December 2020 Featured Publication STUDY DESIGN: Retrospective cohort study. OBJECTIVES: To investigate radiographic sagittal and spinopelvic parameters of patients with adolescent idiopathic scoliosis (AIS) treated with bracing and assess differences among those treated successfully and un ... Full text Link to item Cite

Effect of Instrument Navigation on C-arm Radiation and Time during Spinal Procedures: A Clinical Evaluation.

Journal Article Int J Spine Surg · June 2020 Featured Publication INTRODUCTION: As minimally invasive spine surgery gains popularity, a focused effort must be made to reduce intraoperative radiation exposure to levels as low as reasonably achievable. Here, we demonstrate the clinical efficacy of a novel technology to aid ... Full text Link to item Cite

Complications After Pediatric Hip Fractures: Evaluation and Management.

Journal Article J Am Acad Orthop Surg · January 1, 2020 Pediatric proximal femur fractures are high-energy injuries with predictable and morbid complications. Osteonecrosis of the femoral head is the most common complication with identified risk factors including fracture type, patient's age, degree of displace ... Full text Link to item Cite

Periapical Wires Result in Less Curve Correction Than Pedicle Screw Constructs in Idiopathic Scoliosis.

Journal Article Asian Spine J · December 2019 Featured Publication STUDY DESIGN: Retrospective study. PURPOSE: The objective of this study was to compare percent correction between apical and periapical pedicle screw (PS) and sublaminar wire constructs for Cobb correction and coronal balance correction. OVERVIEW OF LITERA ... Full text Link to item Cite

Effects of Serial Casting with or without Bracing on Sagittal Parameters in Early Onset Scoliosis

Journal Article Spine deformity · November 1, 2019 Featured Publication Full text Cite

Growth-Friendly Spine Surgery in Escobar Syndrome.

Journal Article J Pediatr Orthop · August 2019 Featured Publication BACKGROUND: The aims of this study were to characterize the spinal deformity of patients with Escobar syndrome, describe results of growth-friendly treatments, and compare these results with those of an idiopathic early-onset scoliosis (EOS) cohort to dete ... Full text Link to item Cite

Gradual Deformity Correction in Blount Disease.

Journal Article J Pediatr Orthop · 2019 BACKGROUND: Blount disease is a disorder of the posteromedial proximal tibial physis which causes a progressive varus, procurvatum, and internal rotation deformity of the tibia. Untreated, it can cause significant limb malalignment. The goal of this study ... Full text Link to item Cite

Orthopedic and Surgical Management of the Patient With Duchenne Muscular Dystrophy.

Journal Article Pediatrics · October 2018 Orthopedic care is an important aspect of the overall management of patients with Duchenne muscular dystrophy (DMD). In addition to progressive muscle weakness and loss of function, patients may develop joint contractures, scoliosis, and osteoporosis, caus ... Full text Link to item Cite

IRF2BPL Is Associated with Neurological Phenotypes.

Journal Article Am J Hum Genet · September 6, 2018 Full text Link to item Cite

IRF2BPL Is Associated with Neurological Phenotypes.

Journal Article Am J Hum Genet · August 2, 2018 Interferon regulatory factor 2 binding protein-like (IRF2BPL) encodes a member of the IRF2BP family of transcriptional regulators. Currently the biological function of this gene is obscure, and the gene has not been associated with a Mendelian disease. Her ... Full text Link to item Cite

Pediatric proximal femur fractures

Journal Article Journal of Orthopaedics · June 1, 2018 Pediatric proximal femur fractures are rare injuries resulting from high-energy trauma. The Delbet classification is used when describing these injuries, and associates fracture type to the development of avascular necrosis. Historically, casting was utili ... Full text Cite

Are large clinical trials in orthopaedic trauma justified?

Journal Article BMC Musculoskelet Disord · April 20, 2018 BACKGROUND: The objective of this analysis is to evaluate the necessity of large clinical trials using FLOW trial data. METHODS: The FLOW pilot study and definitive trial were factorial trials evaluating the effect of different irrigation solutions and pre ... Full text Link to item Cite

Looking beyond the exome: a phenotype-first approach to molecular diagnostic resolution in rare and undiagnosed diseases.

Journal Article Genet Med · April 2018 PurposeTo describe examples of missed pathogenic variants on whole-exome sequencing (WES) and the importance of deep phenotyping for further diagnostic testing.MethodsGuided by phenotypic information, three children with negative WES underwent targeted sin ... Full text Open Access Link to item Cite

Analysis of the impact of race on blood transfusion in pediatric scoliosis surgery.

Journal Article Paediatr Anaesth · April 2018 Featured Publication INTRODUCTION: Surgical correction of pediatric scoliosis is associated with significant blood loss. Minimizing estimated blood loss and blood transfusion is beneficial as transfusions have been associated with increased morbidity, including risk of surgica ... Full text Link to item Cite

Pediatric spine disorders and spine trauma

Chapter · January 1, 2018 In recent years, several important advances have been made in the management of spinal deformity in children and adolescents. The efficacy of bracing for idiopathic scoliosis in adolescence was established with a prospective study that evaluated the use of ... Cite

Pediatric Clavicle Injuries

Chapter · January 1, 2017 The human clavicle assists in suspending the upper extremity from the axial skeleton. It is one of the first bones to ossify during human development and contains the last physis to close at the end of skeletal growth. Injuries to the clavicle are common i ... Full text Cite

Neuromuscular Scoliosis: Current Concepts.

Journal Article Orthopedics · June 2015 Featured Publication Scoliosis is a common deformity in neuromuscular disorders. This spinal deformity usually presents at an early age, rapidly progresses during growth, and continues to progress even after skeletal maturity. Neuromuscular scoliosis classically involves the e ... Full text Link to item Cite

Orthopaedic Management of the Child with Muscular Dystrophy

Chapter · January 1, 2015 The orthopaedic care of children with MD is a demanding endeavor. Although many similarities exist, each subtype of MD can present differently. It is imperative that the proper diagnosis be confirmed so that treatment can be initiated based on knowledge of ... Full text Cite

Distant Harrington rod migration 35 years after implantation.

Journal Article J Clin Neurosci · October 2013 Harrington rods have been successfully implanted in thousands of patients for the correction of scoliotic deformity since the 1950s. An exceedingly rare complication of Harrington rod placement is loosening with resultant migration. The authors present a 5 ... Full text Open Access Link to item Cite

Vascularized fibular grafts for avascular necrosis after slipped capital femoral epiphysis: is hip preservation possible?

Journal Article Clin Orthop Relat Res · July 2013 BACKGROUND: Avascular necrosis (AVN) of the femoral head is a potential complication in patients with slipped capital femoral epiphysis (SCFE), radiographically occurring in 3-60%. This may lead to early hip fusion or hip arthroplasty. Free vascularized fi ... Full text Link to item Cite

Bovine xenograft failures in pediatric foot reconstructive surgery.

Journal Article J Pediatr Orthop · June 2013 BACKGROUND: Structural bone grafting serves an important and necessary role during pediatric foot reconstruction. Different bone grafts have been used for such reconstructions including corticocancellous autografts, allografts, and synthetic grafts. Bovine ... Full text Link to item Cite

Osteonecrosis of the femoral head in childhood malignancy.

Journal Article J Child Orthop · March 2013 PURPOSE: Children undergoing chemotherapeutic treatment of malignancies have up to a 9 % incidence of osteonecrosis. The purpose of this article is to determine the time from initiation of chemotherapy to the onset of symptoms and the diagnosis of osteonec ... Full text Link to item Cite

Adding thoracic fusion levels in Lenke 5 curves: risks and benefits.

Journal Article Spine (Phila Pa 1976) · January 15, 2013 Featured Publication STUDY DESIGN: Multicenter; review of prospectively collected data. OBJECTIVE: To determine the risks and potential benefits of nonselective versus selective fusion in a matched set of patients with Lenke 5 curves. SUMMARY OF BACKGROUND DATA: The Lenke clas ... Full text Link to item Cite

Radiographic outcomes of ring external fixation for malunion and nonunion.

Journal Article J Surg Orthop Adv · 2013 Ring external fixators such as the Ilizarov external fixator (IEF) and Taylor Spatial Frame (TSF) have revolutionized management of limb deformity. This study examines radiographic outcomes for treatment of malunions and nonunions with secondary emphasis o ... Full text Link to item Cite

Prevalence of painful peroneal tubercles in the pediatric population.

Journal Article J Foot Ankle Surg · 2012 Pain isolated to the lateral aspect of the heel can be difficult to diagnose, particularly in the growing child. Peroneal tendinopathy or frank tears of the peroneal tendons secondary to an enlarged peroneal tubercle has been implicated as a potential sour ... Full text Link to item Cite

Pamidronate treatment and posttreatment bone density in children with spastic quadriplegic cerebral palsy.

Journal Article J Clin Densitom · 2006 Little is known about the long-term effects of a course of pamidronate treatment on bone mineral density (BMD) of children with spastic quadriplegic cerebral palsy (SQCP). Nine patients with SQCP who had low bone density and/or history of previous fracture ... Full text Link to item Cite

Serum prealbumin and albumin concentrations do not reflect nutritional state in children with cerebral palsy.

Journal Article J Pediatr · November 2005 Serum prealbumin concentration (PALB) and albumin concentration (ALB) were evaluated as markers of undernutrition in 107 children with cerebral palsy (CP) age 2 to 18 years. PALB and ALB were rarely below the normal reference ranges and showed little to no ... Full text Link to item Cite

Efficacy of alendronate in adults with cystic fibrosis with low bone density.

Journal Article Am J Respir Crit Care Med · January 1, 2004 As adults with cystic fibrosis (CF) have enjoyed incremental increases in longevity over the last few decades, they have also been suffering from low bone density and its clinical manifestations, fractures and kyphosis. We conducted a placebo-controlled, r ... Full text Link to item Cite

Short-term calcitriol administration improves calcium homeostasis in adults with cystic fibrosis.

Journal Article Osteoporos Int · June 2003 Osteoporosis is a well-defined health risk in cystic fibrosis (CF) patients due to many factors. Vitamin D insufficiency, despite routine cholecalciferol supplementation in CF patients, may contribute to a relative secondary hyperparathyroidism and possibl ... Full text Link to item Cite

Bisphosphonates to treat osteopenia in children with quadriplegic cerebral palsy: a randomized, placebo-controlled clinical trial.

Journal Article J Pediatr · November 2002 OBJECTIVE: To evaluate in a double-blind, placebo-controlled clinical trial the safety and efficacy of intravenous pamidronate to treat osteopenia in nonambulatory children with cerebral palsy. STUDY DESIGN: Six pairs of subjects generally matched within e ... Full text Link to item Cite

Pediatric reference data for dual X-ray absorptiometric measures of normal bone density in the distal femur.

Journal Article AJR Am J Roentgenol · February 2002 OBJECTIVE: Many children at risk for osteoporosis have substantial hip and knee contractures that prevent assessment of bone mineral density in the "usual" region, the proximal femur. As an alternative, bone density may be measured in the distal femur proj ... Full text Link to item Cite

Abnormal bone turnover in cystic fibrosis adults.

Journal Article Osteoporos Int · 2002 Cystic fibrosis (CF) patients often have low bone mineral density (BMD) and may suffer from fractures and kyphosis. The pathogenesis of low BMD in CF is multifactorial. To study bone metabolism, we collected fasting serum and urine from 50 clinically stabl ... Full text Link to item Cite

Diminished and erratic absorption of ergocalciferol in adult cystic fibrosis patients.

Journal Article Am J Clin Nutr · March 2001 BACKGROUND: Osteoporosis diminishes the quality of life in adults with cystic fibrosis (CF). Vitamin D deficiency resulting from malabsorption may be a factor in the etiology of low bone mineral density (BMD) in patients with CF. OBJECTIVE: Absorption of o ... Full text Link to item Cite

Dual X-ray absorptiometry assessment of body composition in children with altered body posture.

Journal Article J Clin Densitom · 2001 Many children have contractures and/or deformities that preclude positioning in a fully supine position. The purpose of this study was to evaluate the effects of "poor" positioning on the assessment of body composition with dual X-ray absorptiometry (DXA) ... Full text Link to item Cite

Adverse alterations in bone metabolism are associated with lung infection in adults with cystic fibrosis.

Journal Article Am J Respir Crit Care Med · November 2000 Low bone density, fractures, and kyphosis complicate the lives of adults with cystic fibrosis (CF), and inflammatory cytokines (interleukin [IL]-1beta, IL-6, and tumor necrosis factor [TNF]-alpha) that may alter bone metabolism have been previously found t ... Full text Link to item Cite

Efficacy of pamidronate for osteoporosis in patients with cystic fibrosis following lung transplantation.

Journal Article Am J Respir Crit Care Med · September 2000 Lung transplantation with its attendant life-long immunosuppression contributes to bone loss and its sequelae, fractures and kyphosis, in patients with lung disease, many of whom already suffer from severe osteoporosis. Patients with cystic fibrosis (CF) a ... Full text Link to item Cite