Predictors of Persistent Limp Following Proximal Femoral Varus Osteotomy for Perthes Disease.

INTRODUCTION: One of the most popular containment procedures for Legg-Calvé-Perthes disease (LCPD) is proximal femur varus osteotomy (PFO). While generally successful in achieving containment, PFO can cause limb length discrepancy, abductor weakness, and (of most concern for families) a persistent limp. While many studies have focused on radiographic outcomes following containment surgery, none have analyzed predictors of this persistent limp. The aim of this study was to determine clinical, radiographic, and surgical risk factors for persistent limp 2 years after PFO in children with LCPD. METHODS: A retrospective review of a prospectively collected multicenter database was conducted for patients aged 6 to 11 years at disease onset with unilateral early-stage LCPD (Waldenström I) who underwent PFO. Limp status (no, mild, and severe), age, BMI, and pain scores were obtained at initial presentation, 3-month, and 2-year postoperative visits. Preoperative and follow-up radiographs were used to measure traditional morphologic hip metrics including acetabular index (AI), lateral center-edge angle (LCEA), and femoral neck-shaft angle (NSA). Univariate analysis as well as multivariate logistic regression models were used to analyze factors associated with mild and severe limp at the 2-year visit. RESULTS: A total of 95 patients met the inclusion criteria, and of these 50 patients underwent concomitant greater trochanter apophysiodesis (GTA) at the time of PFO. At the 2-year visit, there were 38 patients (40%) with a mild or severe limp. Multivariate logistic regression revealed no significant radiographic factors associated with a persistent limp. However, lower 2-year BMI and undergoing GTA were associated with decreased rates of persistent limp regardless of age ( P <0.05). When stratifying by age of disease onset, apophysiodesis appeared to be protective against any severity of limp in patients aged 6 to 8 years old ( P = 0.03), but not in patients 8 years or older ( P = 0.49). CONCLUSIONS: Persistent limp following PFO is a frustrating problem that was seen in 40% of patients at 2 years. However, lower follow-up BMI and performing a greater trochanter apophysiodesis, particularly in patients younger than 8 years of age, correlated with a lower risk of postoperative limp.

The effect of machine learning predicted anharmonic frequencies on thermodynamic properties of fluid hydrogen fluoride.

Anharmonic effects play a crucial role in determining thermochemical properties of liquids and gases. For such extended phases, the inclusion of anharmonicity in reliable electronic structure methods is computationally extremely demanding, and hence, anharmonic effects are often lacking in thermochemical calculations. In this study, we apply the quantum cluster equilibrium method to transfer density functional theory calculations at the cluster level to the macroscopic, liquid, and gaseous phase of hydrogen fluoride. This allows us to include anharmonicity, either via vibrational self-consistent field calculations for smaller clusters or using a regression model for larger clusters. We obtain the structural composition of the fluid phases in terms of the population of different clusters as well as isobaric heat capacities as an example for thermodynamic properties. We study the role of anharmonicities for these analyses and observe that, in particular, the dominating structural motifs are rather sensitive to the anharmonicity in vibrational frequencies. The regression model proves to be a promising way to get access to anharmonic features, and the extension to more sophisticated machine-learning models is promising.

Koopmans' theorem for acidic protons.

The famous Brønsted acidity, which is relevant in many areas of experimental and synthetic chemistry, but also in biochemistry and other areas, is investigated from a new perspective. Nuclear electronic orbital methods, which explicitly account for the quantum character of selected protons, are applied. The resulting orbital energies of the proton wavefunction are interpreted and related to enthalpies of deprotonation and acid strength in analogy to the Koopmans' theorem for electrons. For a set of organic acids, we observe a correlation which indicates the validity of such a NEO-Koopmans' approach and opens up new opportunities for the computational investigation of more complex acidic systems.

TURBOMOLE: Today and Tomorrow.

TURBOMOLE is a highly optimized software suite for large-scale quantum-chemical and materials science simulations of molecules, clusters, extended systems, and periodic solids. TURBOMOLE uses Gaussian basis sets and has been designed with robust and fast quantum-chemical applications in mind, ranging from homogeneous and heterogeneous catalysis to inorganic and organic chemistry and various types of spectroscopy, light-matter interactions, and biochemistry. This Perspective briefly surveys TURBOMOLE's functionality and highlights recent developments that have taken place between 2020 and 2023, comprising new electronic structure methods for molecules and solids, previously unavailable molecular properties, embedding, and molecular dynamics approaches. Select features under development are reviewed to illustrate the continuous growth of the program suite, including nuclear electronic orbital methods, Hartree-Fock-based adiabatic connection models, simplified time-dependent density functional theory, relativistic effects and magnetic properties, and multiscale modeling of optical properties.

Performance of Common Density Functionals for Excited States of Tetraphenyldibenzoperiflanthene.

Time-dependent density functional theory is the method of choice to efficiently calculate excitation spectra with the functional and basis set choice allowing one to compromise between accuracy and computational cost. In this work, the performance of different functionals as well as the second-order approximate coupled cluster singles and doubles model CC2 is evaluated by comparing the results to experimental results of the example molecule tetraphenyldibenzoperiflanthene (DBP). The choice of the functional has a significant impact on the calculated spectrum of DBP. The performance of a number of different functionals was evaluated, quantified, and, where possible, discussed. The best functional, tuned-CAM-B3LYP, is used to investigate DBP on a surface of hexagonal boron nitride (h-BN). The resulting spectrum shows excellent agreement with experimental results for a monolayer of DBP on h-BN.

Do Weightbearing Restrictions Cause Excess Weight Gain in Children With LEGG-Calvé-Perthes Disease?

BACKGROUND: Restricted weight bearing is commonly prescribed in Legg-Calvé-Perthes Disease (LCPD), raising concerns of causing overweight or obesity. This study utilizes prospectively collected data to address the following questions: (1) does body mass index (BMI) Z-score increase over the course of LCPD follow-up; (2) is having a BMI category of normal, overweight, or obese at baseline associated with BMI Z-score changes over the course of follow-up; and (3) is the duration of weight bearing restrictions (no restrictions, <3, 3 to <6, 6 to 9, or >9 mo) associated with BMI Z-score changes. METHODS: Data of 130 children aged 5 to 12 years with unilateral early-stage LCPD were extracted from an international database. Nation-specific BMI Z-scores and percentile-based weight categories were determined, and the duration of follow-up and weight bearing restrictions were calculated. Longitudinal changes in BMI Z-scores were evaluated for the 3 study questions using mixed effects linear regression models with surgery as a covariate. Sensitivity analyses were used to determine the influence of socio-cultural background (USA vs. India) for each study question. RESULTS: During the 35.5±15.9 months of follow-up, no statistically significant increase in BMI Z-scores was observed across the entire cohort, or following stratification by baseline weight categories or the duration of the weight bearing restriction. Sensitivity analyses indicated that patients in the USA had no change in their BMI Z-score. When stratified by weight categories, the normal weight of US children had a small increase in their BMI Z-score (0.005 per mo, 95% confidence interval: 0.0002, 0.009), but this was not seen in other BMI categories. The cohort of Indian children had a small but significant decrease in their BMI Z-score (-0.005/mo, 95% CI: -0.009, -0.0002). After stratification by weight categories, a small decrease of the BMI Z-score was observed only in the Indian overweight children (-0.016 per mo, 95% CI: -0.027, -0.005) and no other BMI category. CONCLUSIONS: Weightbearing restrictions over the course of follow-up for our cohort of children with early-stage LCPD were not associated with clinically meaningful increases of BMI Z-scores. Weight gain is multi-factorial and probably not caused by weight bearing restrictions alone. LEVEL OF EVIDENCE: III Diagnostic Study.

Controversies in the Management of Unstable Slipped Capital Femoral Epiphysis.

Slipped capital femoral epiphysis (SCFE) involves anterior-superior displacement of the proximal metaphysis relative to the epiphysis of the proximal femur. It is the most common hip disorder affecting the pediatric population. SCFE has a higher incidence in adolescent males in addition to racial and regional predilections. Despite being described over 500 years ago, there remains controversy surrounding the topic. This article examines current concepts in SCFE, with a spotlight on treatment. An evidence-based discussion of treatment controversies regarding reduction method, fixation construct, supplemental procedures and surgical timing is included.

Reliability and Validity of Visual Estimation of Femoral Head Hypoperfusion on Perfusion MRI in Legg-Calve-Perthes Disease.

BACKGROUND: Assessing the severity of Legg-Calve-Perthes disease is important for treatment decision-making and determining prognosis. Perfusion magnetic resonance imaging (MRI) scans have improved our ability to assess femoral head hypoperfusion, and the use of an image analysis software called HipVasc (Scottish Rite for Children, Dallas TX) has allowed precise quantification for research purposes. In the clinical setting, using HipVasc software is not practical, and visual estimation is used to assess hypoperfusion. Currently, the reliability of visual estimation is unknown. The purpose of this study was to determine the reliability and validity of visual estimation of hypoperfusion on perfusion MRI and compare the results to measurements obtained with the HipVasc software. METHODS: Fourteen pediatric orthopaedic surgeons, divided into 4 groups, participated in this study. Each surgeon completed a 30-minute in-person training on HipVasc before proceeding. Stratified by category of severity, 122 MRIs were randomly assigned to 1 of the 4 groups so that each group member measured the same set of ∼30 MRIs. Each surgeon documented their visual estimation of hypoperfusion first, then used HipVasc to measure the hypoperfusion and recorded their results. Interobserver reliability was assessed at the group level by calculating the intraclass correlation coefficient. RESULTS: Good correlation and reliability was found between the visual estimate and HipVasc measurements with an overall mean intraclass correlation coefficient of 0.87 and mean Pearson coefficient of 0.90. The mean interobserver reliability of visual estimation was 0.84. Observers had a tendency to overestimate hypoperfusion with visual estimation. CONCLUSIONS: This study demonstrates the reliability and validity of visual estimation as a clinically applicable method for determining femoral head hypoperfusion. Our study is the first to measure the reliability of visual estimation and HipVasc with a large cohort of clinicians, specifically pediatric orthopaedic surgeons with varied experience in graphical software analysis. We recommend using visual estimation as a clinically applicable method to make treatment decisions, and its accuracy is comparable to HipVasc software analysis. LEVEL OF EVIDENCE: Level III-diagnostic.

Hip Morphology in Early-stage LCPD: Is There an Argument for Anatomic-specific Containment?

BACKGROUND: Early containment surgery has become increasingly popular in Legg-Calvé-Perthes Disease (LCPD), especially for older children. These procedures treat the proximal femur, the acetabulum, or both, and most surgeons endorse the same surgical option regardless of an individual patient's anatomy. This "one-surgery-fits-all" approach fails to consider potential variations in baseline anatomy that may make one option more sensible than another. We sought to describe hip morphology in a large series of children with newly diagnosed LCPD, hypothesizing that variation in anatomy may support the concept of anatomic-specific containment. METHODS: A retrospective review of a prospectively collected multicenter database was conducted for patients aged 6 to 11 at diagnosis. To assess anatomy before significant morphologic changes secondary to the disease itself, only patients in Waldenström stages IA/IB were included. Standard hip radiographic measurements including acetabular index, lateral center-edge angle, proximal femoral neck-shaft angle (NSA), articulotrochanteric quartiles, and extrusion index (EI) were made on printed anteroposterior pelvis radiographs. Age-specific percentiles were calculated for these measures using published norms. Significant outliers (≤10th/≥90th percentile) were reported where applicable. RESULTS: A total of 168 patients with mean age at diagnosis of 8.0±1.3 years met inclusion criteria (81.5% male). Mean acetabular index for the entire cohort was 16.8±4.1 degrees; 58 hips (34.5%) were significantly dysplastic compared with normative data. Mean lateral center-edge angle was 15.9±5.2 degrees at diagnosis; 110 (65.5%) were ≤10th percentile indicating dysplasia (by this metric). Mean NSA overall was 136.5±7.0 degrees. Fifty-one (30.4%) and 20 (11.9%) hips were significantly varus (≤10th percentile) or valgus (≥90th percentile), respectively. Thirty-five hips (20.8%) were the third articulo-trochanteric quartiles or higher suggesting a higher-riding trochanter at baseline. Mean EI was 15.5%±9.0%, while 63 patients (37.5%) had an EI ≥20%. CONCLUSIONS: The present study finds significant variation in baseline anatomy in children with early-stage LCPD, including a high prevalence of coexisting acetabular dysplasia as well as high/low NSAs. These variations suggest that the "one-surgery-fits-all" approach may lack specificity for a particular patient; a potentially wiser option may be an anatomic-specific containment operation (eg, acetabular-sided osteotomy for coexisting dysplasia, varus femoral osteotomy for valgus NSA). LEVEL OF EVIDENCE: Level IV.

Atomistic Descriptors for Machine Learning Models of Solubility Parameters for Small Molecules and Polymers.

Descriptors derived from atomic structure and quantum chemical calculations for small molecules representing polymer repeat elements were evaluated for machine learning models to predict the Hildebrand solubility parameters of the corresponding polymers. Since reliable cohesive energy density data and solubility parameters for polymers are difficult to obtain, the experimental heat of vaporization ΔHvap of a set of small molecules was used as a proxy property to evaluate the descriptors. Using the atomistic descriptors, the multilinear regression model showed good accuracy in predicting ΔHvap of the small-molecule set, with a mean absolute error of 2.63 kJ/mol for training and 3.61 kJ/mol for cross-validation. Kernel ridge regression showed similar performance for the small-molecule training set but slightly worse accuracy for the prediction of ΔHvap of molecules representing repeating polymer elements. The Hildebrand solubility parameters of the polymers derived from the atomistic descriptors of the repeating polymer elements showed good correlation with values from the CROW polymer database.

Bilateral Femoral Neck Fractures in the Setting of Bilateral Slipped Capital Femoral Epiphysis: A Case Report.

CASE: A 16-year-old adolescent boy with autism and vitamin D deficiency sustained a seizure and had bilateral femoral neck fractures and slipped capital femoral epiphysis (SCFEs). He underwent closed reduction and screw stabilization of femoral neck fractures with incorporation of in situ screw fixation of SCFEs. Intraosseous epiphyseal perfusion monitoring was used to confirm the perfusion of the femoral head. Two years postoperatively, he had healed fractures and no evidence for avascular necrosis. CONCLUSION: A femoral neck fracture in the setting of a SCFE can be treated with closed reduction of the femoral neck fracture and screw fixation. Intraepiphyseal perfusion monitoring can be used to qualitatively assess femoral head perfusion.

Increased Hip Intracapsular Pressure Decreases Perfusion of the Capital Femoral Epiphysis in a Skeletally Immature Porcine Model.

BACKGROUND: Increased intracapsular hip pressure is thought to be one of the possible etiologies of femoral head avascular necrosis after intra-articular proximal femoral fractures or acute slipped capital femoral epiphysis. The purpose of this study was to evaluate the relationship between intra-articular hip pressure (IAP) and epiphyseal perfusion pressure (EPP), and its dependency on skeletal maturity using a porcine model. METHODS: Seven female Yorkshire-hybrid pigs were used to study the direct relationship between IAP and EPP. A needle inserted into the capsule provided both IAP monitoring and saline infiltration until IAP was above mean arterial pressure (MAP). Video simultaneously documented IAP, EPP, MAP. Parameters for all trials in each hip were averaged and compared between the 2 age groups. Significance was P<0.05. RESULTS: Four young hips (in pigs 10.3±1.0 wk, 27.4±2.0 kg) and 5 older hips (21.1±0.1 wk, 89.4±7.1 kg) were studied. There was no significant difference in the MAP (50.0±11.8 and 55.5±7.0 mm Hg respectively, P=0.411) between the 2 age groups. In the older hips, biphasic EPP persisted despite increasing IAP to an average of 177 mm Hg over MAP. In the young pigs, the biphasic EPP waveform ceased with increased IAP to an average of 28 mm Hg over MAP. Biphasic waveforms returned once IAP fell to an average of 5 mm Hg over MAP. CONCLUSIONS: Increased IAP resulted in tamponade of epiphyseal perfusion in the young, but not in the older hips. An intact physis may preclude intraosseous metaphyseal vessels from penetrating the epiphysis, leaving it vulnerable to retinacular artery tamponade. CLINICAL RELEVANCE: The IAP and EPP relationship has direct clinical practice implications. Hip capsulotomy and decompression in young patients with intra-articular proximal femoral fractures and increased intracapsular pressure may decrease avascular necrosis risk.

Validation of Pediatric Self-Report Patient-Reported Outcomes Measurement Information System (PROMIS) Measures in Different Stages of Legg-Calvé-Perthes Disease.

OBJECTIVES: Patient-reported outcomes (PRO) assessing health-related quality of life (HRQoL) are important outcome measures, especially in Legg-Calvé-Perthes disease (LCPD) where symptoms (pain and limping), activity restrictions, and treatments vary depending on the stage of the disease. The purpose of this study was to investigate the validity of the Patient-reported Outcomes Measurement Information System (PROMIS) for measuring HRQoL of patients with LCPD in various stages of the disease. METHODS: This is a multicenter validity study. Patients with LCPD between 4 and 18 years old were included and classified into modified Waldenström stages of disease: Early (1 or 2A), Late (2B or 3), or Healed (4). Seven PROMIS domains were collected, including Pain Interference, Fatigue, Mobility, Depression, Anger, Anxiety, and Peer Relationships. Convergent, discriminant, and known group validity was determined. RESULTS: A total of 190 patients were included (mean age: 10.4±3.1 y). All 7 domains showed the worst scores in patients in the Early stage (known group validity). Within each domain, all domains positively correlated to each other (convergent validity). Patients who reported more anxiety, depression, and anger were associated with decreased mobility and increased fatigue and pain. Peer relationships had no to weak associations with other domains (discriminant validity). CONCLUSIONS: PROMIS has construct validity in measuring the HRQoL of patients in different stages of LCPD, suggesting that PROMIS has potential to serve as a patient-reported outcome tool for this population. LEVEL OF EVIDENCE: Diagnostic level III study.

Capsulotomy in Unstable Slipped Capital Femoral Epiphysis and the Odds of AVN: A Meta-analysis of Retrospective Studies.

BACKGROUND: Unstable slipped capital femoral epiphysis (SCFE) may lead to avascular necrosis (AVN) in up to 60% of patients. The aim of this study was to assess the best clinical evidence to determine the effect of capsular decompression (CD) on odds of AVN in unstable SCFE. METHODS: Medline, Embase, and Cochrane databases were systematically searched for comparative studies investigating AVN rates in unstable SCFE treated with or without CD (aspiration, percutaneous, or open). Quality was evaluated by the Newcastle Ottawa Scale. A comparative analysis with pooled effect estimates using random-effects modeling was calculated. Secondary analysis pooled AVN rates from both comparative studies and case series. RESULTS: Comparative analysis included 17 retrospective studies with 453 hips (201 with CD, 252 without CD). Thirty-four of 201 (17%) hips with CD developed AVN, while 67 of 252 (27%) hips without CD developed AVN. The odds of AVN for patients treated with or without CD [odds ratio=0.80, 95% confidence interval (CI): 0.48-1.35] was not statistically different. Subanalysis on patients treated with in situ pinning or positional reduction and pinning showed no difference in AVN rates with or without CD (odds ratio=0.97, 95% CI: 0.44-2.10). In the secondary analysis of 17 comparative studies and 23 case series, the average rate of AVN was 17%, 0.17 (95% CI: 0.13-0.23) for patients treated with CD (60/447 hips) and 28%, 0.28 (95% CI: 0.22-0.35) for patients treated without CD (129/464 hips). CONCLUSIONS: There was no statistically significant decrease in odds of AVN with CD. However, studies were limited by their retrospective nature and inadequate documentation of CD techniques; the majority lacked femoral head blood flow monitoring to demonstrate adequate decompression. Future prospective studies with carefully documented complete decompression may help to elucidate the effect of CD on AVN risk. Although there was no statistically different odds of AVN with or without CD, even this large meta-analysis was underpowered, and one cannot conclude that there was truly no difference in odds of AVN without an appropriately powered study. Therefore, we recommend routine CD for all unstable SCFEs pending additional research, as CD adds little to the surgical procedure and may minimize the risk of a devastating insult to the femoral head.

Late acetabular dysplasia after successful treatment for developmental dysplasia of the hip using the Pavlik method: A systematic literature review.

The Pavlik method is the most common method used for treatment of developmental dysplasia of the hip (DDH). Late acetabular dysplasia despite successful treatment, however, has had varied reporting. A systematic review was performed, investigating the long-term outcomes of DDH treated with the Pavlik method. Seventeen studies met inclusionary criteria, including 6029 hips treated with an average of 5.29 years follow-up. Radiographic evidence of late dysplasia was present in 280 hips, with 109 hips requiring additional surgery. A specified treatment algorithm had significantly decreased rates of radiographic dysplasia (3.8% vs 17.6%, p = 0.004). LEVEL OF EVIDENCE: IV.

Arthroscopic Management of Pigmented Villonodular Synovitis of the Hip in Children and Adolescents.

BACKGROUND: Pigmented villonodular synovitis (PVNS) is a benign proliferative synovial disorder most commonly described to affect the knee in adults. Literature describing PVNS in the pediatric population is limited to 2 small case series and a handful of single-patient case reports. Within these studies, only 2 patients with PVNS of the hip are described. PURPOSE: To describe the presentation, management, and outcomes of a single-center series of pediatric patients with PVNS of the hip treated with arthroscopic synovectomy. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective review of consecutive pediatric patients treated for PVNS at a single institution was performed. Inclusion criteria consisted of patients younger than 19 years with surgically treated PVNS of the hip. RESULTS: Five pediatric patients with a mean age of 11.0 years were treated for PVNS of the hip from 2011 to 2016. The mean duration of symptoms from onset to surgical treatment was 247 days (range, 3-933 days). Upon review of magnetic resonance imaging (MRI) results, radiologists included PVNS in their differential in 3 patients. Seven surgeries were performed in 5 patients. All therapeutic procedures were arthroscopic synovectomies. Nodular PVNS was present in 4 patients, and diffuse disease was present in 1 patient. At a mean 32-month follow-up (range, 12-63 months), all patients were considered to be free of recurrence based on clinical examination and/or follow-up MRI. Four patients were asymptomatic and returned to all of their previous sports activities. CONCLUSION: Young age at the time of diagnosis is a point to be highlighted in this cohort, and symptoms may be present for many months prior to diagnosis due to the failure to consider PVNS in children. Therefore, for patients with "atypical" presentations or lack of improvement with treatment for rheumatologic, bleeding, or infectious disorders, PVNS should be strongly considered. MRI with gradient echo sequences is the diagnostic imaging study of choice. One patient with diffuse involvement and preoperative degenerative changes showed progressive changes postoperatively. This type of PVNS may have a worse prognosis, but more diffuse cases are needed before the prognosis can be determined. Arthroscopic synovectomy following a timely diagnosis of PVNS produces good outcomes in nodular cases, with no evidence of symptomatic or radiographic disease persistence among these patients.

Intraoperative Monitoring of Epiphyseal Perfusion in Slipped Capital Femoral Epiphysis: Surgical Technique.

INTRODUCTION: Intraoperative monitoring of epiphyseal perfusion in slipped capital femoral epiphysis (SCFE) is a procedurally simple and readily accessible percutaneous technique to accurately guide decision-making and help to prevent osteonecrosis. STEP 1 PATIENT PREPARATION AND POSITIONING: Following anesthesia induction, position the patient and assess the physeal stability fluoroscopically to determine the need for a reduction. STEP 2 GUIDEWIRE PLACEMENT: Place a 3.2-mm threaded guidewire from the anterolateral aspect of the femur to provide initial stability of the slipped epiphysis. STEP 3 INITIAL SCREW INSERTION: Insert a cannulated 7.0-mm stainless steel screw over the guidewire to a point just past the physis. STEP 4 PREPARATION AND INSERTION OF THE ICP PROBE: Once the screw has been inserted to obtain provisional stability of the physis, remove the guidewire and insert a sterile ICP probe down the screw shaft to assess the epiphyseal perfusion. STEP 5 HIP DECOMPRESSION: If a perfusion pressure and waveform cannot be obtained, perform decompression of the hip capsule by either aspiration or capsulotomy. STEP 6 EPIPHYSEAL PERFUSION REASSESSMENT: Following the capsulotomy, reinsert the ICP probe and reassess the epiphyseal perfusion. STEP 7 FINAL SCREW ADVANCEMENT: Once epiphyseal blood flow can be confirmed, reintroduce the guidewire to its previous depth and advance the screw to the final measured depth. RESULTS: Utilizing this technique over a 5-year period, >35 patients were treated with the described technique, and 23 of them, including 29 hips, were included in our referenced prospective study3.

Intraoperative Monitoring of Epiphyseal Perfusion in Slipped Capital Femoral Epiphysis.

BACKGROUND: The purposes of this study were to validate an innovative, percutaneous method of monitoring femoral head (epiphyseal) perfusion intraoperatively in patients with slipped capital femoral epiphysis (SCFE) and to investigate an association between intraoperative perfusion and the subsequent development of osteonecrosis. METHODS: A percutaneous screw fixation technique for SCFE was utilized. A fully threaded, cannulated, stainless-steel 7.0-mm screw was inserted into the epiphysis. The guidewire was removed, and a sterile intracranial pressure (ICP) probe was placed through the screw such that the tip was in the epiphyseal bone past the end of the screw. Intraoperative epiphyseal pressure and waveform were recorded. A prospective analysis of patients undergoing percutaneous screw fixation for unstable or stable SCFE or for prophylactic treatment with the use of this technique to evaluate femoral head perfusion was performed. RESULTS: This technique was used in 23 patients (29 hips, including 15 hips with unstable SCFE, 11 with stable SCFE, and 3 treated prophylactically). Three hips (2 with unstable SCFE and 1 treated prophylactically) in 2 patients were eliminated from the analysis because of technical problems with the ICP monitor. All hips with stable SCFE and the prophylactically treated hips had measurable pulsatile flow that was synchronous with the patient's heart rate at the initial time of probe insertion. Seven patients (7 hips) with unstable SCFE had measurable, pulsatile flow with initial insertion of the probe, and 6 patients (6 hips) with unstable SCFE had no measurable flow. We were able to demonstrate perfusion following a percutaneous capsular decompression in the patients with no initial flow. All patients left the operating room with measurable femoral head blood flow. At a mean follow-up of 1.6 years for hips with stable SCFE and 2.0 years for those with unstable SCFE, no hip subsequently developed radiographic evidence of osteonecrosis of the femoral head. No complications from the use of the ICP monitor occurred. CONCLUSIONS: Femoral head perfusion in patients with SCFE can be measured intraoperatively using this technique. Demonstrating femoral head perfusion before leaving the operating room was associated with the absence of osteonecrosis postoperatively. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Medial and lateral pin versus lateral-entry pin fixation for Type 3 supracondylar fractures in children: a prospective, surgeon-randomized study.

BACKGROUND: The purpose of this study is to compare the efficacy of medial and lateral (crossed pin) and lateral-entry pin techniques for Gartland Type 3 supracondylar humerus fractures in children. METHODS: Six pediatric orthopaedists were divided into the 2 treatment groups (medial and lateral pins or lateral only pins) based on pre-study pinning technique preferences. Patients were randomized into 1 of the 2 pinning technique treatment groups based on which attending was on call at the time of patient presentation. One hundred and four patients met inclusion criteria. Forty-seven patients underwent lateral-entry pinning and 57 underwent crossed pinning. The 2 groups were similar with respect to age, sex, preoperative neurovascular injury, direction of fracture displacement, and timing of surgery. Outcome parameters measured included radiographic maintenance of reduction, iatrogenic neurovascular complications, and rate of infection. All radiographic measurements, and interobserver reliability, were determined by a 3 physician panel. RESULTS: The results of the interobserver reliability data showed a strong correlation and this data allowed 95% confidence that a change in Baumann's angle of more than 6 degrees and humerocapitellar angle of more than 10 degrees was significant. The lateral-entry patients experienced a median absolute change of Baumann's angle of 3.7 degrees with 12 patients having greater than 6 degrees loss of reduction; whereas those in the medial and lateral-pin group saw a median change of 2.9 degrees with 10 patients having greater than 6 degrees loss of reduction. In terms of the humerocapitellar angle, the lateral-entry patients experienced a median absolute change of 4.8 degrees with 11 patients having greater than 10 degrees loss of reduction; whereas those in the medial and lateral-pin groups saw a median change of 5.1 degrees with 17 patients having greater than 10 degrees loss of reduction. There was no significant difference in infection rate between the 2 groups but 2 cases of iatrogenic neurovascular injury occurred in patients who had a medial pin placed. CONCLUSIONS: We found no statistical difference in the radiographic outcomes between lateral-entry and medial and lateral-pin techniques for the management of Type 3 supracondylar fractures in children when evaluated in this prospective and surgeon-randomized trial, but 2 cases of iatrogenic injury to the ulnar nerve occurred with medially placed pins. LEVEL OF EVIDENCE: Level 2.