Conference report on contractures in musculoskeletal and neurological conditions.

Limb contractures are debilitating complications associated with various muscle and nervous system disorders. This report summarizes presentations at a conference at the Shirley Ryan AbilityLab in Chicago, Illinois, on April 19-20, 2018, involving researchers and physicians from diverse disciplines who convened to discuss current clinical and preclinical understanding of contractures in Duchenne muscular dystrophy, stroke, cerebral palsy, and other conditions. Presenters described changes in muscle architecture, activation, extracellular matrix, satellite cells, and muscle fiber sarcomeric structure that accompany or predispose muscles to contracture. Participants identified ongoing and future research directions that may lead to understanding of the intersecting factors that trigger contractures. These include additional studies of changes in muscle, tendon, joint, and neuronal tissues during contracture development with imaging, molecular, and physiologic approaches. Participants identified the requirement for improved biomarkers and outcome measures to identify patients likely to develop contractures and to accurately measure efficacy of treatments currently available and under development.

Preoperative Pulmonary Function Test Results Are Not Associated With Postoperative Intubation in Children Undergoing Posterior Spinal Fusion for Scoliosis: A Retrospective Observational Study.

BACKGROUND: Preoperative pulmonary function tests are routinely obtained in children with scoliosis undergoing posterior spinal fusion despite unclear benefits as a perioperative risk assessment tool and frequent inability of patients to provide acceptable results. The goal of this study was to determine whether preoperative pulmonary function test results are associated with the need for postoperative intubation or intensive care unit admission after posterior spinal fusion. METHODS: The electronic medical records of patients who underwent posterior spinal fusion at a pediatric tertiary hospital between June 2012 and August 2017 were reviewed. Pulmonary function tests were consistently ordered for all patients, unless the patient was deemed unable to perform the test due to cognitive disability. Cases were categorized as primary or secondary scoliosis.Demographic data, preoperative bilevel positive airway pressure use, Cobb angle, intraoperative allogeneic blood transfusion, and ability to produce acceptable pulmonary function test results were collected for each patient. In patients with satisfactory pulmonary function test results, forced vital capacity and maximum inspiratory pressure were collected. Primary outcomes for analysis were postoperative intubation and intensive care unit admission. Univariable logistic regression models were used to assess the association between each variable of interest and the primary outcomes. RESULTS: The study sample included 433 patients, 288 with primary scoliosis and 145 with secondary scoliosis. Among patients with primary scoliosis, 90% were able to produce acceptable pulmonary function test results, zero remained intubated postoperatively, and 6 were admitted to the intensive care unit. Among patients with secondary scoliosis, 44% could not attempt pulmonary function tests. Among those who did attempt the test, 30% were unable to produce meaningful results. Forced vital capacity and maximum inspiratory pressure were not found to be associated with postoperative intubation or intensive care unit admission. Weight, Cobb angle, intraoperative blood transfusion, American Society of Anesthesiologists physical status classification, and preoperative bilevel positive airway pressure use were associated with patient outcomes. Among 357 total patients who attempted pulmonary function tests, 37 had high-risk results. Only 1 of these 37 patients remained intubated postoperatively. CONCLUSIONS: Patients undergoing posterior spinal fusion, especially those with secondary scoliosis, are frequently unable to adequately perform pulmonary function tests. Among patients with interpretable pulmonary function tests, there was no association between results and postoperative intubation or intensive care unit admission. Routine pulmonary function testing for all patients with scoliosis may not be indicated for purposes of risk assessment before posterior spinal fusion. Clinicians should consider a targeted approach and limit pulmonary function tests to patients for whom results may guide preoperative optimization as this may improve outcomes and reduce inefficiencies and costs.

Cotransplantation with specific populations of spina bifida bone marrow stem/progenitor cells enhances urinary bladder regeneration.

Spina bifida (SB) patients afflicted with myelomeningocele typically possess a neurogenic urinary bladder and exhibit varying degrees of bladder dysfunction. Although surgical intervention in the form of enterocystoplasty is the current standard of care in which to remedy the neurogenic bladder, it is still a stop-gap measure and is associated with many complications due to the use of bowel as a source of replacement tissue. Contemporary bladder tissue engineering strategies lack the ability to reform bladder smooth muscle, vasculature, and promote peripheral nerve tissue growth when using autologous populations of cells. Within the context of this study, we demonstrate the role of two specific populations of bone marrow (BM) stem/progenitor cells used in combination with a synthetic elastomeric scaffold that provides a unique and alternative means to current bladder regeneration approaches. In vitro differentiation, gene expression, and proliferation are similar among donor mesenchymal stem cells (MSCs), whereas poly(1,8-octanediol-cocitrate) scaffolds seeded with SB BM MSCs perform analogously to control counterparts with regard to bladder smooth muscle wall formation in vivo. SB CD34(+) hematopoietic stem/progenitor cells cotransplanted with donor-matched MSCs cause a dramatic increase in tissue vascularization as well as an induction of peripheral nerve growth in grafted areas compared with samples not seeded with hematopoietic stem/progenitor cells. Finally, MSC/CD34(+) grafts provided the impetus for rapid urothelium regeneration. Data suggest that autologous BM stem/progenitor cells may be used as alternate, nonpathogenic cell sources for SB patient-specific bladder tissue regeneration in lieu of current enterocystoplasty procedures and have implications for other bladder regenerative therapies.

Spinal growth modulation using a novel intravertebral epiphyseal device in an immature porcine model.

PURPOSE: Fusionless growth modulation is an attractive alternative to conventional treatments of idiopathic scoliosis. To date, fusionless devices achieve unilateral growth modulation by compressing the intervertebral disc. This study explores a device to control spinal alignment and vertebral morphology via growth modulation while excluding the disc in a porcine model. METHODS: A device that locally encloses the vertebral growth plate exclusive of the disc was introduced anteriorly over T5-T8 in four immature pigs (experimental) while three underwent surgery without instrumentation (sham) and two were selected as controls. Bi-weekly coronal and lateral radiographs were taken over the 12-week follow-up to document vertebral morphology and spinal alignment modifications via an inverse approach (creation of deformity). RESULTS: All animals completed the experiment with no postoperative complications. Control and sham groups showed no significant changes in spinal alignment. Experimental group achieved a final coronal Cobb angle of 6.5° ± 3.5° (constrained to the four instrumented levels) and no alteration to the sagittal profile was observed. Solely the experimental group ended with consistent vertebral wedging of 4.1° ± 3.6° amounting to a cumulative wedging of up to 25° and a concurring difference in left/right vertebral height of 1.24 ± 1.86 mm in the coronal plane. CONCLUSIONS: The proposed intravertebral epiphyseal device, for the early treatment of progressive idiopathic scoliosis, demonstrated its feasibility by manipulating spinal alignment through the realization of local growth modulation exclusive of the intervertebral disc.

Lesional and nonlesional skin from patients with untreated juvenile dermatomyositis displays increased numbers of mast cells and mature plasmacytoid dendritic cells.

OBJECTIVE: To investigate the distribution of mast cells and dendritic cell (DC) subsets in paired muscle and skin (lesional/nonlesional) from untreated children with juvenile dermatomyositis (DM). METHODS: Muscle and skin biopsy samples (4 skin biopsy samples with active rash) from 7 patients with probable/definite juvenile DM were compared with muscle and skin samples from 10 healthy pediatric controls. Mast cell distribution and number were assessed by toluidine blue staining and analyzed by Student's t-test. Immunohistochemical analysis was performed to identify mature DCs, myeloid DCs (MDCs), and plasmacytoid DCs (PDCs) by using antibodies against DC-LAMP, blood dendritic cell antigen 1 (BDCA-1), and BDCA-2, respectively. Myxovirus resistance protein A (MxA) staining indicated active type I interferon (IFN) signaling; positive staining was scored semiquantitatively and analyzed using the Mann-Whitney U test. RESULTS: Both inflamed and nonlesional skin from patients with juvenile DM contained more mast cells than did skin from pediatric controls (P = 0.029), and comparable numbers of mast cells were present in lesional and nonlesional skin. Interestingly, mast cell numbers were greater in skin than in paired muscle tissue from patients with juvenile DM (P = 0.014) and were not increased in muscle from patients with juvenile DM compared with control muscle. Both muscle and skin from patients with juvenile DM showed more mature PDCs and MxA staining than did their corresponding control tissues (P < 0.05). In both muscle and skin from patients with juvenile DM and in pediatric control muscle, there were fewer MDCs than PDCs, and the distributions of MDCs and PDCs were similar in pediatric control skin samples. CONCLUSION: The identification of mast cells in skin (irrespective of rash) from patients with juvenile DM, but not in paired muscle tissue, suggests that they have a specific role in juvenile DM skin pathophysiology. In skin from patients with juvenile DM, increased numbers of PDCs and increased expression of type I IFN-induced protein suggest a selective influence on T cell differentiation and subsequent effector function.

Elucidating the inherent features of IS to better understand idiopathic scoliosis etiology and progression.

Idiopathic Scoliosis (IS) is a relatively common condition and is estimated to affect as many as 3 % of youth aged 10-17 years (in the United States an estimated approximately 1.4 million otherwise healthy individuals). A clear understanding of the etiology will better direct optimization of evaluation, treatments and therapies, especially early treatments with less invasive methods. A mechanistic explanation of factors combining to initiate and then cause progression of this common condition-- in otherwise healthy pre-teenage and teenage patients--will be discussed. A recent well-designed structured systematic review states that 'strong evidence is lacking for a consistent pattern of occurrence and any abnormality', in other words there is no strong evidence for 'other associated diagnoses' in IS. And so, certain important inherent factors of IS merit greater discussion. Inherent, or intrinsic factors include: a natural susceptibility to develop a lateral and rotational deformity in the immature rapidly growing erect human spine, inherent torsion associated at the induction of deformity, biomechanics related to curve progression, and anthropology/bipedal gait. We know more today about factors related to the condition and its etiology than we have previously. Across multiple disciplines, a mechanistic approach to understanding the etiopathogenesis of IS, allows a reasonable 'theory' for IS etiology and its progression. We will discuss these inherent intrinsic factors in order to further add to our understanding of the theoretical etiopathogenesis. A better understanding of the etiology (and progression) may better direct ways to optimize evaluation, treatments and therapies, especially early treatments with less invasive methods.

Idiopathic scoliosis: A pilot MR study of early vertebral morphological changes and spinal asymmetry.

Adolescent idiopathic scoliosis (AIS) a common spinal condition affecting adolescents. Though the etiology is still unknown, it is widely thought to have a multifactorial etiology and early diagnosis remains a significant challenge. The purpose of this study is to identify early vertebral morphological changes and patterns of spinal asymmetry in these at-risk individuals who later progress to adolescent idiopathic scoliosis. This was a retrospective study of patients treated for AIS between 1997 and 2017. We utilized two study groups, a group with immature onset of spinal asymmetry and a control group. Inclusion criteria for the immature onset group was defined by a Cobb angle between 10 and 40° diagnosed prior to the age of 12 with MRI scans and XRs available for review. Qualitative assessments observed for sagittal vertebral wedging, analysis of vertebral corner anatomy, spinal harmony, and sagittal balance. These findings were then qualitatively compared between groups. Twenty patients were included in this study, ten each in the immature onset and control groups. In the immature onset group, two patients had sagittal wedging, five had abnormal vertebral corners, nine did not have spinal harmony, and nine had negative sagittal balance, compared to none of the control patients having sagittal wedging, none having abnormal vertebral corners, all having spinal harmony, and nine having positive spinal balance. This pilot MRI study identifies qualitative vertebral morphological changes in patients who progress to AIS. Our findings suggest abnormal vertebral corner anatomy, sagittal wedging, and negative sagittal balance as potential early findings in patients who develop AIS.

IS (Idiopathic Scoliosis) etiology: Multifactorial genetic research continues. A systematic review 1950 to 2017.

OBJECTIVE: IS (idiopathic scoliosis) is a common spinal condition occurring in otherwise completely healthy adolescents. The root cause of IS remains unclear. This systematic review will focus on an update of genetic factors and IS etiology. Though it is generally accepted that the condition is not due to a single gene effect, etiology studies continue looking for a root cause including genetic variants. Though susceptibility from multiple genetic components is plausible based on known family history data, the literature remains unclear regarding multifactorial genetic influences. The objective of this study was to critically evaluate the evidence behind genetic causes (not single gene) of IS through a systematic review and strength-of-study analysis of existing genetic and genome-wide association studies (GWAS). We used the protocol of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). METHODS: PubMed was searched for the terms IS, scoliotic, spinal curve, genetic, gene, etiology, polymorphisms. Articles were assessed for risk-of-bias. Level-of-evidence grading was completed via Oxford Centre for Evidence-Based Medicine criteria. The assessment scores factor strength of a study in determining a positive or negative association to a gene etiology. RESULTS: After screening of 36 eligible papers, 8 relevant studies met inclusion criteria at this time, 3 were in favor of a genetic factor for IS, whereas 5 studies were against it. CONCLUSION: Based on the literature analyzed, there is moderate evidence with a low risk-of-bias that does not clarify a genetic cause of IS. The 2 studies in favor of a genetic etiology were completed in homogeneous populations, limiting their generalizability. Relying on a genetic etiology alone for IS may over simplify its multifactorial nature and limit appreciation of other influences.

Survivorship of allograft ACL reconstruction in adolescent patients.

PURPOSE: The overall benefits of ACL reconstructive surgery in young athletes has been previously established. Graft selection for ACL reconstruction, specifically in this population however, remains controversial. The literature is limited and long-term survival rate of allograft ACL reconstruction in the adolescent population remains poorly defined. Current evidence, none level I, appears to demonstrate increased failure and subsequent revision rates in allograft reconstruction of complete ACL tears compared to autograft; 7-35% compared to 3-13% respectively. The purpose of the present study was to evaluate revision rate and functional outcomes of allograft ACL reconstruction in the adolescent population at extended follow-up. METHODS: A retrospective chart review was performed. Forty patients who underwent transphyseal ACL reconstruction with either bone patellar tendon bone (BTB) or Achilles tendon bone (ATB) allograft performed by a single surgeon over a 12-year period were identified. Demographic and surgical details were analyzed. Enrolled patients completed a Lysholm Knee Scoring Scale and a Tegner Activity Level Scale during phone interviews. All secondary surgeries performed on the ipsilateral knee were recorded. RESULTS: Twenty-five patients were enrolled; fifteen were lost to follow-up. There were ten male and fifteen female patients included for analysis. Average age at index surgery was 16 years (range 13-18 years). BTB allograft was used for seven patients, and ATB allograft was used for the remaining eighteen patients. Average follow-up was 54 months (range 13-136 months). The average Lysholm score at follow-up was 87 (range 57-100). The average Tegner score at follow-up was 6.8 (range 3-10). Three patients underwent revision ACL surgery (12% study group, 7.5% all) for traumatic re-rupture. Re-rupture occurred 12, 13 and 38 months after index surgery. CONCLUSIONS: Autograft remains the standard for ACL reconstruction in the general pediatric population. In the adolescent population, however, the use of BTB or ATB allograft is a reasonable alternative with satisfactory outcomes, decreased harvest site morbidity, decreased post-operative pain and faster rehabilitation. The traumatic re-rupture rate in this series was similar to previously published traumatic failure rates in young adult athletes after reconstruction with autologous tissue (11-13%). Further prospective studies are needed to determine any true difference in the use of either allograft or autograft in the adolescent population.

Thoracolumbar fracture-dislocation in child abuse: case report, closed reduction technique and review of the literature.

There have been very few reports in the literature of management of thoracolumbar fracture dislocations in very young children. The following is a presentation of one of these rare cases that was treated using a closed reduction method that has been little described in the medical literature. A 14-month-old child suffered a fracture dislocation at T(12)-L(1) from nonaccidental trauma. The patient was neurologically intact upon admission. Treatment consisted of closed manual reduction and hyperextension casting under sedation. At 22-month follow-up, the patient displayed excellent clinical and radiographic results and remained neurologically intact. The operative technique is presented in detail and relevant literature reviewed. We propose that closed reduction and extension casting may be an acceptable treatment for infantile thoracolumbar fracture dislocations in neurologically intact patients.

Compartment syndrome following intraosseous infusion.

Intraosseous infusion is a valuable technique in the resuscitation of critically ill pediatric patients in whom vascular access has proved otherwise impossible. Although it is well established as a safe and reliable means of emergent access, intraosseous infusion is not without danger, nor complication. One of the rare yet most grave complications of intraosseous access is compartment syndrome. We report a case of compartment syndrome as a result of intraosseous infusion that serves to remind of the potential pitfalls of this technique. An otherwise healthy 6-year-old girl presented to our institution's pediatric intensive care unit following emergent resuscitation for a prolonged cardiac arrest. Approximately 1 hour following an uneventful soccer practice, without any antecedent cardiopulmonary symptoms or complaints, the patient collapsed and was unresponsive, not breathing, and pulseless. In the course of resuscitation, right and left tibial intraosseous lines were started. After 30 minutes of resuscitation, with multiple rounds of lidocaine and epinephrine infused through the intraosseous lines, a sustained perfusing rhythm was established. Acute compartment syndrome was diagnosed, and through anterolateral and posteromedial incisions, all 4 fascial compartments were released. While the condition of the patient's extremity improved, the overall clinical condition of the patient did not. This case highlights the fundamental principles regarding the use of intraosseous infusion and the diagnosis and management of compartment syndrome in critically ill patients.

Evaluation of angle trunk rotation measurements to improve quality and safety in the management of adolescent idiopathic scoliosis.

PURPOSE: The evaluation, management and follow-up of adolescent idiopathic scoliosis (AIS) occur frequently within a pediatric orthopedic surgery practice. Curve status can be assessed with Scoliometer measurements of angle trunk rotation (ATR), which are reliable and reproducible to within 3°. This study assessed the longitudinal efficacy, safety and cost savings of integrating ATR measurements to monitor curve status and progression in AIS, and suggests a quality-based management strategy. METHODS: A retrospective review of medical records between 2004 and 2014 included patients with AIS between 10-17 years, excluding those with Cobb angle >52° at presentation. Two cohorts were analyzed based on presentation prior to menarche (PRE) or after menarche (POST). The PRE groups was further classified based on whether the curve was Stable or Unstable. The cost of a single PA thoracolumbar radiograph was defined based on the 2015 CMS fee schedule ($36.27). Safety was defined based on the effective radiation dose avoided (0.14 millisieverts/radiograph). RESULTS: A total of 59 children were included with 45 in PRE and 14 in the POST cohort. The use of ATR measurements provided a cost benefit in both the PRE Stable and Unstable cohorts, by avoiding radiographs with an average savings of $161.76 and $147.50 respectively. Similarly in POST, there was an average cost savings of $105.18 per patient. The safety benefit of using ATR measurements included avoiding an average of 0.62, 0.56 and 0.4 millisieverts of radiation in the PRE Stable, PRE Unstable and POST groups respectively. CONCLUSIONS: An evaluation strategy with ATR measurements provides for a reliable, cost-effective and safety advantage in the monitoring of curve progression in both skeletally mature and immature patients with AIS. These findings suggest that stable ATR measurements are a safe and cost effective alternative to serial radiographs in the clinical monitoring of AIS. Recent evidence from 25 years of scoliosis treatment in Denmark noted a cancer rate 17 times that of an age-matched population. Thus, reducing radiation exposure during scoliosis monitoring using ATR measurements has important clinical significance for cancer risk reduction.

Long leg splinting for pediatric femur fractures.

BACKGROUND: Pediatric femur fractures are frequently encountered injuries frequently treated with spica casting. Spica casting may, however, be expensive and burdensome to patients. A possible alternative is a long leg splint. METHODS: Patients aged 6 months to 5 years old who were treated for a femoral shaft fracture with a long leg splint extending above the waist were matched with a patient treated with a spica cast. RESULTS: At the time of healing, the alignment in the spica cast group was only significantly better than the alignment of the splint group with respect to coronal angulation.

Simulation-Based Educational Module Improves Intern and Medical Student Performance of Closed Reduction and Percutaneous Pinning of Pediatric Supracondylar Humeral Fractures.

BACKGROUND: Simulation-based education has been integrated into many orthopaedic residency programs to augment traditional teaching models. Here we describe the development and implementation of a combined didactic and simulation-based course for teaching medical students and interns how to properly perform a closed reduction and percutaneous pinning of a pediatric supracondylar humeral fracture. METHODS: Subjects included in the study were either orthopaedic surgery interns or subinterns at our institution. Subjects all completed a combined didactic and simulation-based course on pediatric supracondylar humeral fractures. The first part of this course was an electronic (e)-learning module that the subjects could complete at home in approximately 40 minutes. The second part of the course was a 20-minute simulation-based skills learning session completed in the simulation center. Subject knowledge of closed reduction and percutaneous pinning of supracondylar humeral fractures was tested using a 30-question, multiple-choice, written test. Surgical skills were tested in the operating room or in a simulated operating room. Subject pre-intervention and post-intervention scores were compared to determine if and how much they had improved. RESULTS: A total of 21 subjects were tested. These subjects significantly improved their scores on both the written, multiple-choice test and skills test after completing the combined didactic and simulation module. Prior to the module, intern and subintern multiple-choice test scores were significantly worse than postgraduate year (PGY)-2 to PGY-5 resident scores (p < 0.01); after completion of the module, there was no significant difference in the multiple-choice test scores. After completing the module, there was no significant difference in skills test scores between interns and PGY-2 to PGY-5 residents. Both tests were validated using the scores obtained from PGY-2 to PGY-5 residents. CONCLUSIONS: Our combined didactic and simulation course significantly improved intern and subintern understanding of supracondylar humeral fractures and their ability to perform a closed reduction and percutaneous pinning of these fractures.

Congenital and developmental deformities of the spine in children with myelomeningocele.

The treatment of spinal deformities in children with myelomeningocele poses a formidable task. Multiple medical comorbidities, such as insensate skin and chronic urinary tract infection, make care of the spine difficult. A thorough understanding of the natural history of these deformities is mandatory for appropriate treatment to be rendered. A team approach that includes physicians from multiple specialties provides the best care for these patients. The two most challenging problems are paralytic scoliosis and rigid lumbar kyphosis. The precise indications for surgical intervention are multifactorial, and the proposed benefits must be weighed against the potential risks. Newer spinal constructs now allow for fixation of the spine in areas previously difficult to instrument. Complications appear to be decreasing with improved understanding of the pathophysiology associated with myelomeningocele.

The surgical management of pediatric fractures of the upper extremity.

The vast majority of pediatric fractures of the upper extremity can and should be treated with closed reduction, immobilization, and close follow-up. However, there is an ongoing debate in the orthopaedic community regarding the exact role of surgical management in the treatment of pediatric fractures. In the past 2 decades, surgical management of certain fractures (e.g., percutaneous pinning of displaced supracondylar fractures) has provided better results than closed management. Surgical management is clearly indicated for certain injuries, such as those requiring anatomic realignment of the physis or articular surface. Increasingly, however, surgical management is being used to maintain optimal alignment or to allow early motion. In many such cases, both nonsurgical and surgical methods have yielded good results and have vocal advocates. Certain technical advances, such as flexible intramedullary fixation and bioreabsorbable implants, have further increased enthusiasm for surgical management of pediatric fractures.

Functional and radiographic outcomes of juvenile osteochondritis dissecans of the knee treated with extra-articular retrograde drilling.

BACKGROUND: Osteochondritis dissecans (OCD) lesions of the medial femoral condyle in the adolescent population can cause significant impairment and restriction in physical activity. Studies have established the efficacy of transarticular antegrade drilling for juvenile OCD lesions of the knee, although concerns of consequences from drilling through the articular cartilage remain. Alternatively, retrograde extra-articular drilling avoids drilling the cartilage while ensuring adequate channels for revascularization and healing. PURPOSE: The authors present the results of 31 skeletally immature patients who underwent retrograde drilling of OCD lesions of the knee with an average follow-up of 4 years. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The procedure consisted of a standard arthroscopic evaluation of the knee and subsequent percutaneous retrograde drilling obliquely through the condylar epiphysis starting distal to the physis and ending in the center-center of the OCD lesion. Outcome measures included radiographic signs of healing, Lysholm scoring and the Tegner activity scale to measure performance and activity restriction, and visual analog scale (VAS) pain scores. RESULTS: Average follow-up for the 31 patients was 4 years (range, 1.5-7 years). Sixteen of the 34 lesions were grade I or II based on radiographic findings with signs and symptoms greater than 6 months. The remaining 18 were grade III secondary to a sclerotic rim surrounding the defect. Overall, improvement in Lysholm scores (70 to 95; standard deviation [SD] ± 14.95), Tegner scores (4 to 7; SD ± 2.31), and VAS pain scores (6.9 to 1.3; SD ± 2.16) were found to be statistically significant. Radiographs showed stable or improved lesions in all cases. CONCLUSION: Retrograde extra-articular drilling provided clinical and radiographic improvement in most juveniles with OCD lesions who failed nonoperative management. This method serves to decompress the lesion and allow revascularization without disrupting the articular cartilage surface in stable OCD lesions.