MRI of the Spine in Patients who Toe Walk: Is There a Role?

BACKGROUND: Little is known about the prevalence of intraspinal pathology in children who toe walk, but magnetic resonance imaging (MRI) may be part of the diagnostic workup. The purpose of this study was to examine the role of MRI for children who toe walk with a focus on the rate of positive findings and associated neurosurgical interventions performed for children with said MRI findings. METHODS: A single-center tertiary hospital database was queried to identify a cohort of 118 subjects with a diagnosis of toe walking who underwent spinal MRI during a 5-year period. Patient and MRI characteristics were summarized and compared between subjects with a major abnormality, minor abnormality, or no abnormality on MRI using multivariable logistic regression. Major MRI abnormalities included those with a clear spinal etiology, such as fatty filum, tethered cord, syrinx, and Chiari malformation, while minor abnormalities had unclear associations with toe walking. RESULTS: The most common primary indications for MRI were failure to improve with conservative treatment, severe contracture, and abnormal reflexes. The prevalence of major MRI abnormalities was 25% (30/118), minor MRI abnormalities was 19% (22/118), and normal MRI was 56% (66/118). Patients with delayed onset of toe walking were significantly more likely to have a major abnormality on MRI ( P =0.009). The presence of abnormal reflexes, severe contracture, back pain, bladder incontinence, and failure to improve with conservative treatment were not significantly associated with an increased likelihood of major abnormality on MRI. Twenty-nine (25%) subjects underwent tendon lengthening, and 5 (4%) underwent neurosurgical intervention, the most frequent of which was detethering and sectioning of fatty filum. CONCLUSIONS: Spinal MRI in patients who toe walk has a high rate of major positive findings, some of which require neurosurgical intervention. The most significant predictor of intraspinal pathology was the late onset of toe walking after the child had initiated walking. MRI of the spine should be considered by pediatric orthopedic surgeons in patients with toe walking who present late with an abnormal clinical course. LEVEL OF EVIDENCE: Level III Retrospective Comparative Study.

Barriers to Discharge After Hip Reconstruction Surgery in Non-ambulatory Children With Neurological Complex Chronic Conditions.

BACKGROUND: Hip reconstruction surgery in patients with neurological complex chronic conditions (CCC) is associated with prolonged hospitalization and extensive resource utilization. This population is vulnerable to cognitive, developmental, and medical comorbidities which can increase length of stay (LOS). The aims of this study were to characterize barriers to discharge for a cohort of children with neurological CCC undergoing hip reconstruction surgery and to identify patient risk factors for prolonged hospitalization and delayed discharge. METHODS: Retrospective chart review of nonambulatory patients with neurological CCC undergoing hip reconstruction surgery between 2007-2016 was conducted. Hospitalization ≥1 day past medical clearance was characterized as delayed discharge. Barriers were defined as unresolved issues at the time of medical clearance and categorized as pertaining to the caregiver and patient education, durable medical equipment, postdischarge transportation/placement, and patient care needs. RESULTS: The cohort of 116 patients was 53% male, 16% non-English speaking, and 49% Gross Motor Function Classification System (GMFCS) V with the mean age at surgery of 9.1±3.64 years. Median time from admission to medical clearance was 5 days with median LOS of 6 days. Approximately three-quarters of patients experienced delayed discharge (73%) with barriers identified for 74% of delays. Most prevalent barriers involved education (30%) and durable medical equipment (29%). Postdischarge transportation and placement accounted for 26% of barriers and 3.5 times longer delays ( P <0.001). Factors associated with delayed discharge included increased medical comorbidities ( P <0.05) and GMFCS V ( P <0.001). Longer LOS and medical clearance times were found for female ( P =0.005), older age ( P <0.001), bilateral surgery ( P =0.009), GMFCS V ( P =0.003), and non-English-speaking patients ( P <0.001). CONCLUSIONS: Patients with neurological CCC frequently encounter postoperative barriers contributing to increased LOS and delayed discharge. Patients that may be at higher risk for prolonged hospitalization and greater resource utilization include those who are female sex, adolescent, GMFCS V, non-English speaking, have additional comorbidities, and are undergoing bilateral surgery. Standardized preoperative assessment of educational needs, perioperative equipment requirements, and posthospital transportation may decrease the LOS, reduce caregiver and patient burden/distress, cost, and ultimately reduce variation in care delivery. LEVEL OF EVIDENCE: Level III, Retrospective Case Series.

Validation of a Novel Magnetic Resonance Imaging Classification for Osteochondritis Dissecans of the Knee.

BACKGROUND: The novel Kocher classification is a 3-group magnetic resonance imaging (MRI) classification system for osteochondritis dissecans (OCD) of the knee that was shown to have comparable reliability to that of the established 5-group Hefti classification. The purpose of this study was to evaluate the validity and clinical utility of this simplified system as an alternative to the Hefti classification. METHODS: Demographic data and arthroscopic findings were retrospectively collected from medical and surgical records of 144 consecutive knees in children with arthroscopically diagnosed knee OCD. OCD lesions on preoperative MRIs and surgical reports (serving as the reference standard) were assessed by independent raters and assigned both a Kocher and Hefti classification. Agreement between MRI classification and arthroscopic findings for both systems was assessed using weighted kappa (kw) coefficients. Validation, accuracy, sensitivity, and specificity were measured by comparing a dichotomized Kocher classification for MRI and arthroscopy, and by estimating Cohen kappa (kc) coefficients. Agreement between arthroscopic findings and treatment type was measured using the Spearman correlation coefficient. RESULTS: Inter-rater reliability between the 2 MRI raters was substantial for the Kocher classification [ka=0.66; 95% confidence interval (CI)=0.56-0.75] and moderate for the Hefti classification (ka=0.57; 95% CI=0.47-0.67). There was no difference detected in the agreement statistics for Kocher versus Hefti classifications (P=0.89). Binary agreement using dichotomized Kocher classifications was worse than the 3-group category classification. When dichotomized, combining Kocher grades 1 and 2 demonstrated moderate agreement (kc=0.41; 95% CI=0.25-0.58), and combining grades 2 and 3 demonstrated fair agreement (kc=0.34; 95% CI=0.21-0.48). There was a strong correlation between arthroscopy-based finding and treatment category for both the Kocher classification (r=0.85; 95% CI=0.80-0.89) and the Hefti classification (r=0.82; 95% CI=0.75-0.86). CONCLUSION: The validity and clinical utility of the newer 3-group Kocher classification for knee OCD is comparable to that of the well-established 5-group Hefti classification. Both systems help determine lesion stability and characteristics on MRI, which correlate closely to arthroscopic findings. This simplified classification system, with less uncertainty, provides a foundation for further outcomes research to develop an evidence-based algorithm for effective surgical management of OCD lesions of the knee. LEVEL OF EVIDENCE: Level II-diagnostic study.

Incidence and Risk Factors for Heterotopic Ossification in a Matched Cohort Adolescent Population Undergoing Hip Arthroscopy.

BACKGROUND: Heterotopic ossification (HO) is a known complication after hip arthroscopy in adults, positively associated with larger cam resection, male sex, older age, and obesity, and negatively associated with nonsteroidal anti-inflammatory drug (NSAID) use and capsular closure. However, it has not been well-documented in adolescents. The purpose of this study was to determine the incidence and risk factors for the development of HO in adolescent patients undergoing hip arthroscopy. METHODS: Clinical and operative records from a pediatric institution were queried to identify patients aged 21 years or younger who underwent hip arthroscopy between 2008 and 2018. The 27 cases that developed HO were matched 1:4 on age and sex with 107 controls. The bivariate analysis assessed the relationship between demographic and perioperative factors on the development of HO. Multivariable logistic regression evaluated the association between prophylactic NSAID use (indomethacin 75 mg, 3 wk) and HO, controlling for surgeon and extent of cam resection (change in alpha angle). RESULTS: Twenty-seven of 595 (4.5%) hips that underwent hip arthroscopy developed HO within 2 years of surgery. Prophylactic indomethacin was not significantly associated with developing HO [30% (8/27), P=0.83], after controlling for surgeon and extent of cam resection-nor were age, sex, and body mass index percentile. Of patients who developed HO, a smaller proportion underwent reoperation for HO excision among those who received prophylactic indomethacin than those who did not [13% (1/8) vs. 63% (12/19), P=0.03]. CONCLUSIONS: The incidence of HO within 2 years of hip arthroscopy in this adolescent population was 4.5%. Although studies in the adult hip arthroscopy population have pointed to a protective role of NSAIDs (eg, indomethacin) in radiographic HO, the effect was less certain in this adolescent sample. Larger studies are important to further evaluate the role of prophylactic NSAIDs and variations in arthroscopic technique in developing HO. LEVEL OF EVIDENCE: Level III-therapeutic, case-control study.

Strengthening national capacities for pandemic preparedness: a cross-country analysis of COVID-19 cases and deaths.

The International Health Regulations-State Party Annual Reporting (IHR-SPAR) index and the Global Health Security Index (GHSI) have been developed to aid in strengthening national capacities for pandemic preparedness. We examined the relationship between country-level rankings on these two indices, along with two additional indices (the Universal Health Coverage Service Coverage Index and World Bank Worldwide Governance Indicator (n = 195)) and compared them to the country-level reported coronavirus disease (COVID-19) cases and deaths (Johns Hopkins University COVID-19 Dashboard) through 17 June 2020. Ordinary least squares regression models were used to compare weekly reported COVID-19 cases and death rates per million in the first 12 weeks of the pandemic between countries classified as low, middle and high ranking on each index while controlling for country socio-demographic information. Countries with higher GHSI and IHR-SPAR index scores experienced fewer reported COVID-19 cases and deaths but only for the first 8 weeks after the country's first case. For the GHSI, this association was further limited to countries with populations below 69.4 million. For both the GHSI and IHR-SPAR, countries with a higher sub-index score in human resources for pandemic preparedness reported fewer COVID-19 cases and deaths in the first 8 weeks after the country's first reported case. The Universal Health Coverage Service Coverage Index and Worldwide Governance Indicator country-level rankings were not associated with COVID-19 outcomes. The associations between GHSI and IHR-SPAR scores and COVID-19 outcomes observed in this study demonstrate that these two indices, although imperfect, may have value, especially in countries with a population under 69.4 million people for the GHSI. Preparedness indices may have value; however, they should continue to be evaluated as policy makers seek to better prepare for future global public health crises.

Preoperative Considerations for Teenagers Undergoing Orthopaedic Surgery: VTE Prevention, Mental Health Assessment, Vaping, and Drug Addiction.

INTRODUCTION: Adolescents undergoing pediatric orthopaedic surgery typically experience an uncomplicated postoperative course. However, adolescence represents a unique transition period from pediatric to adult physiology. As a result, the astute pediatric orthopaedic surgeon will be aware of unique medical and social scenarios which are relevant to adolescents during the perioperative course including the risk of venous thromboembolism (VTE), prevalence of mental health conditions, and rising use of electronic cigarettes or "vaping" to consume nicotine and cannibas. DISCUSSION: Adolescents are at a greater risk of VTE after pediatric orthopaedic surgery. In particular, adolescent females with a family history of blood clotting disorders and those with a change in mobility after surgery should be considered for prophylaxis. The prevalence of adolescent mental health conditions including anxiety, depression, and behavioral issues is increasing in the United States. Higher levels of preoperative anxiety and the presence of mental health pathology are associated with slower recovery, higher levels of postoperative pain, and the increased likelihood for chronic pain. Several quick screening instruments are available to assess adolescents for preoperative anxiety risk, including the Visual Analogue Scale for Anxiety or the Amsterdam Perioperative Anxiety Information Scale. Unfortunately, electronic cigarettes have become increasingly popular for the consumption of nicotine and cannabis among adolescents. Preoperative use of combustive cigarettes (nicotine/cannabis) represents perioperative risks for induction/anesthesia, postoperative pain, and analgesia requirements and issues with delayed wound and fracture healing. CONCLUSIONS: VTE, underlying mental health conditions, and usage of nicotine and cannabis are clear detriments to the recovery and healing of adolescent patients following orthopaedic surgery. Therefore, standardized screening for adolescents before orthopaedic surgery is indicated to identify perioperative risk factors which have negative impacts on functional outcomes.

Determination of electroosmotic and electrophoretic mobility of DNA and dyes in low ionic strength solutions.

Nanocoding, a genome analysis platform, relies on very low ionic strength conditions to elongate DNA molecules up to 1.06 (fully stretched DNA = 1). Understanding how electroosmotic and electrophoretic forces vary, as ionic strength decreases, will enable better Nanocoding devices, or other genome analysis platforms, to be developed. Using gel electrophoresis to determine overall mobility (includes contributions from electrophoretic and electroosmotic forces) in different ionic strength conditions, linear DNA molecules (pUC19 (2.7 kb), pBR322 (4.4 kb), ΦX174 (5.4 kb), and PSNAPf-H2B (6.2 kb)) were analyzed in varying gel concentrations (1.50, 1.25, 1.00, 0.75, and 0.50%). Additionally, buffer concentration (Tris-EDTA, TE) was varied to determine free solution mobility at different ionic strength solutions. As ionic strength decreased from 13.8 to 7.3 mM, overall mobility increased. As TE buffer decreased (< 7.3 mM), overall mobility drastically decreased as ionic strength decreased. Rhodamine B dye was utilized to determine the electroosmotic mobility. As the ionic strength decreased, electroosmotic mobility increased. The experimental electrophoretic mobility was compared to theoretical considerations for electrophoretic mobility (Pitts and Debye-Hückel-Onsager). Electroosmotic forces decreased the overall mobility of DNA molecules and bromophenol blue migration in a gel matrix as ionic strength decreased.