Variables affecting complication rates in type III paediatric supracondylar humerus fractures.

PURPOSE: Unstable supracondylar humerus (SCH) fractures may have different outcomes as a result of direction of displacement and pin configuration. This study evaluates the impact of fracture displacement, pin configuration and fellowship training on clinical and radiographic outcomes in unstable fractures. METHODS: A total of 99 patients with completely displaced type III fractures were identified at an academic centre and a local community hospital. Patient characteristics and the fellowship training of the treating surgeon were recorded, and injury films documented the direction of displacement. Pin configuration, coronal and sagittal alignment were recorded from postoperative radiographs and at healing. Radiographic outcomes including coronal, sagittal and rotational malunion as well as clinical complications were analyzed. RESULTS: Fractures with direct posterior displacement had a lower composite malunion rate compared with those with posterolateral (PL) or posteromedial (PM) displacement (6.9%, 36.4%, 29.2% respectively; p = 0.019). PM displacement had a higher rate of coronal malunion compared with PL (18.2% versus 0%; post hoc p = 0.024). All-lateral constructs resulted in more rotational malunions (20.9% versus 1.8%; p = 0.002) compared with crossed pinning. PL fractures treated with all-lateral fixation showed a trend toward increased rotational instability or malunion (23.8% versus 1.3%; p = 0.073). Higher composite complication rates were noted in patients treated by surgeons with non-paediatric, non-trauma fellowship training. CONCLUSION: For displaced SCH fractures, all-lateral fixation is associated with higher rates of rotational instability and malunion. Posteromedially and posterolaterally displaced fractures have higher rates of malunion compared with fractures with straight posterior displacement. Fellowship training other than paediatric or trauma was associated with increased complications. LEVEL OF EVIDENCE: Level III.

Is There a Connection Between Attention Deficit Hyperactivity Disorder and Osteochondritis Dissecans?

Background: To determine if children with Osteochondritis Dessicans (OCD) lesions of the distal femur are more likely to have a co-morbid diagnosis of Attention Deficit/ Hyperactivity Disorder (ADHD) than age matched controls and to assess the impact of ADHD on OCD outcomes. Methods: A retrospective chart review of patients treated at a single tertiary care hospital between 2000-2012 was performed. Charts were reviewed for a diagnosis of OCD of the distal femur in all skeletally immature patients (males < 16 years and females < 14 years). These were then screened for a comorbid diagnosis of ADHD. Age-matched controls with anterior knee pain without OCD were then reviewed to determine if ADHD was more common in the OCD population. Treatment and outcomes of the OCD lesions were then compared in children with and without ADHD. Results: The prevalence of ADHD was 23% in patients with OCD lesions and was significantly greater than the 11% found in the anterior knee pain age-matched controls (p<0.05). The average grade of lesions at presentation was similar in both groups (2.2 ADHD vs 2.1 no ADHD) however, at final follow-up, the average OCD grade was significantly worse for children with ADHD (1.4 vs 0.7, p<0.004). Conclusion: There is a significantly higher prevalence of ADHD in children with OCD lesions compared with age-matched controls. This study suggests children that with osteochondritis dessicans and ADHD may not have as favorable treatment course as children without the hyperactivity disorder.Level of Evidence: III.

Compartment Syndrome in Operatively Managed Pediatric Monteggia Fractures and Equivalents.

BACKGROUND: Acute compartment syndrome (ACS) is not commonly associated with pediatric Monteggia fractures or Monteggia equivalents (MF/ME). The aims of this study were: (1) To document a rate of ACS among children with operatively managed MF/ME, comparing this to the rate of ACS in classically associated Type 3 supracondylar humerus (T3-SCH) fractures at the same institution; (2) To determine which patients with MF/ME are at highest risk for ACS. METHODS: Children ages 2 to 12 with MF/ME requiring operative management at an academic institution over a 14-year period were identified. The Monteggia fractures were characterized using the Bado classification; equivalent injuries were identified according to established criteria. Similarly, all patients with T3-SCH fractures managed over the same period were identified. Record review included demographic, procedural, and radiographic variables. Statistical analysis compared the rates of ACS in both groups and determined risk factors associated with developing ACS in patients with MF/ME. RESULTS: The rate of ACS in MF/ME was 9 of the 59 (15.3%), which was significantly higher than the rate of ACS in T3-SCH fractures 2 of the 230 (0.9%) (P=0.001). Comparing MF/ME with ACS to those without; there was no difference in sex (P=1.00), Bado Type (P=0.683), or Monteggia fracture versus equivalent (P=0.704). MF/ME with preoperative vascular deficits (22.2%) and those undergoing intramedullary fixation of the radius were more likely to develop ACS (P=0.021 and 0.015, respectively), and there was a trend toward higher rates of ACS among MF/ME with preoperative neurological deficits (P=0.064). CONCLUSIONS: Patients with operatively managed MF/ME had a significantly higher rate of ACS compared with patients with T3-SCH fractures. With no predisposition based on Bado classification or Monteggia fracture versus equivalent, all operatively managed MF/ME appear to be at risk for ACS. Patients with preoperative neurovascular deficits and those undergoing intramedullary radial fixation develop ACS at higher rates. Careful assessment of the forearm for signs and symptoms of ACS both before and after fixation is critical. LEVEL OF EVIDENCE: Level III-retrospective case control.

Does the sequential addition of accelerometer-based navigation and sensor-guided ligament balancing improve outcomes in TKA?

AIMS: A significant percentage of patients remain dissatisfied after total knee arthroplasty (TKA). The aim of this study was to determine whether the sequential addition of accelerometer-based navigation for femoral component preparation and sensor-guided ligament balancing improved complication rates, radiological alignment, or patient-reported outcomes (PROMs) compared with a historical control group using conventional instrumentation. METHODS: This retrospective cohort study included 371 TKAs performed by a single surgeon sequentially. A historical control group, with the use of intramedullary guides for distal femoral resection and surgeon-guided ligament balancing, was compared with a group using accelerometer-based navigation for distal femoral resection and surgeon-guided balancing (group 1), and one using navigated femoral resection and sensor-guided balancing (group 2). Primary outcome measures were Patient-Reported Outcomes Measurement Information System (PROMIS) and Knee injury and Osteoarthritis Outcome (KOOS) scores measured preoperatively and at six weeks and 12 months postoperatively. The position of the components and the mechanical axis of the limb were measured postoperatively. The postoperative range of motion (ROM), haematocrit change, and complications were also recorded. RESULTS: There were 194 patients in the control group, 103 in group 1, and 74 in group 2. There were no significant differences in baseline demographics between the groups. Patients in group 2 had significantly higher baseline mental health subscores than control and group 1 patients (53.2 vs 50.2 vs 50.2, p = 0.041). There were no significant differences in any PROMs at six weeks or 12 months postoperatively (p > 0.05). There was no difference in the rate of manipulation under anaesthesia (MUA), complication rates, postoperative ROM, or blood loss. There were fewer mechanical axis outliers in groups 1 and 2 (25.2%, 14.9% respectively) versus control (28.4%), but this was not statistically significant (p = 0.10). CONCLUSION: The sequential addition of navigation of the distal femoral cut and sensor-guided ligament balancing did not improve short-term PROMs, radiological outcomes, or complication rates compared with conventional techniques. The costs of these added technologies may not be justified. Cite this article: Bone Joint J 2020;102-B(6 Supple A):24-30.

Two Cases Illustrating the Diagnostic Challenge of Pediatric Blastomycosis Presenting as Osteomyelitis.

Blastomyces dermatitidis is a dimorphic fungus endemic to the United States and Canada. Although both Histoplasma and Blastomyces are found in similar geographic regions, Blastomyces is many times more likely to cause dissemination in the immunocompetent host, frequently involving the bone. However, given the indolent nature of this fungal infection and more prevalent bacterial etiologies of osteomyelitis, diagnosis and treatment are often significantly delayed. We review 2 pediatric cases that initially presented with isolated orthopedic symptoms without documented fever or pulmonary complaints, although both had signs of pulmonary infection on imaging. These cases demonstrate the importance of a high level of suspicion as well as appropriate diagnostic workup, including surgical pathology with fungal stains, when evaluating osteomyelitis in patients exposed to a Blastomyces-endemic region.

Open Vs. Closed Reduction in Type 2 Lateral Condyle Fractures.

Background: Lateral condyle fractures are associated with high morbidity due to their risk of nonunion and avascular necrosis (AVN). This study aims to assess the outcomes between closed reduction and the more traditional open techniques for operative fractures. Methods: All lateral condyle fractures that required operative fixation (pins or screws) over a ten-year period were included. We compared open versus closed reduction for OR time, infection rate, AVN, nonunion, premature physeal closure, ulnohumeral angle, and interepicondylar width (IEW). Results: 28 patients were identified in the closed reduction group while 41 were identified in the open reduction group. Average displacement at surgery for these two groups was significantly different at 3.95mm for the closed group and 9.47mm for the open group (p<0.0001). Operating room time was significantly greater for the open reduction group by an average of 45 minutes (p <0.0001). Additionally, the closed reduction group was significantly less likely to require postoperative admission compared to the open reduction group (p=0.0004). There were no significant differences between the two groups with regard to abnormal ulnohumeral angles, infection rates, avascular necrosis, nonunion, lateral spur formation, premature physeal closure, or reoperation rate. Conclusions: The significant differences in OR time and post-operative admission make closed reduction the preferred approach from a hospital system quality improvement standpoint.Level of Evidence: IV.

Biomechanics of Tendon Transfers.

The transfer of tendons in the upper extremity is a powerful technique to restore function to a partially paralyzed hand. The biomechanical principles of muscle tension and tendon excursion dictate motor function both in the native as well as transferred states. Appropriately tensioning transferred tendons to maximize the function of the associated muscle remains an area of focused research. Newer methods of tendon coaptation have proven similar in strength to the standard Pulvertaft weave, affording more options to the surgeon.

Using the epigenetic field defect to detect prostate cancer in biopsy negative patients.

PURPOSE: We determined whether a novel combination of field defect DNA methylation markers could predict the presence of prostate cancer using histologically normal transrectal ultrasound guided biopsy cores. MATERIALS AND METHODS: Methylation was assessed using quantitative Pyrosequencing® in a training set consisting of 65 nontumor and tumor associated prostate tissues from University of Wisconsin. A multiplex model was generated using multivariate logistic regression and externally validated in blinded fashion in a set of 47 nontumor and tumor associated biopsy specimens from University of Washington. RESULTS: We observed robust methylation differences in all genes at all CpGs assayed (p <0.0001). Regression models incorporating individual genes (EVX1, CAV1 and FGF1) and a gene combination (EVX1 and FGF1) discriminated nontumor from tumor associated tissues in the original training set (AUC 0.796-0.898, p <0.001). On external validation uniplex models incorporating EVX1, CAV1 or FGF1 discriminated tumor from nontumor associated biopsy negative specimens (AUC 0.702, 0.696 and 0.658, respectively, p <0.05). A multiplex model (EVX1 and FGF1) identified patients with prostate cancer (AUC 0.774, p = 0.001) and had a negative predictive value of 0.909. Comparison between 2 separate cores in patients in this validation set revealed similar methylation defects, indicating detection of a widespread field defect. CONCLUSIONS: A widespread epigenetic field defect can be used to detect prostate cancer in patients with histologically negative biopsies. To our knowledge this assay is unique, in that it detects alterations in nontumor cells. With further validation this marker combination (EVX1 and FGF1) has the potential to decrease the need for repeat prostate biopsies, a procedure associated with cost and complications.

Impact of immediate TRUS rebiopsy in a patient cohort considering active surveillance for favorable risk prostate cancer.

INTRODUCTION AND OBJECTIVE: Active surveillance (AS) is an option for the management of favorable risk prostate cancer (CaP) in the PSA era. Published studies have reported variable inclusion criteria for cohort selection. Accurate assessment of individual patient risk in AS is dependent not only upon rigorous selection criteria, but also reliability of diagnosis at tissue biopsy. To date, the impact of immediate transrectal ultrasound (TRUS) rebiopsy in confirming candidates for AS has been incompletely defined. METHODS: From a total of over 567 men, 67 met criteria for AS (Gleason <7, PSA <10, PSAD <0.15, <3 cores with <50% involvement of any 1 core). Fifty-two men agreed to a 12-core TRUS rebiopsy within 6 months of first diagnosis performed in clinic. Statistical analysis was performed using Wilcoxon signed rank test and logistic regression to determine predictors of rebiopsy characteristics, histopathologic outcomes, and impact on treatment choice. RESULTS: Mean cohort age was 63.9 years (range 56-72 years), PSA 5.9 ng/ml (4.1-10), and PSA density 0.12 ng/ml/cc at initial biopsy. Tumor involved 1.1 cores and 3.2% (range 1%-5%) of the total tissue. Average time to rebiopsy was 2.7 months. Notably, 29 of 52 men (56%) demonstrated no evidence of CaP on repeat biopsy; 14 of 23 men with a positive repeat biopsy showed either an increase in cancer volume (2.8% mean increase) and 9 (18%) were upgraded to Gleason pattern 3+4 = 7. Rebiopsy demonstrated 9 (17%) patients exceeded AS criteria. Nine patients chose curative surgical intervention (radical prostatectomy) based on increased cancer volume or grade (4) or an elective desire for treatment (5). All had organ confined disease with negative margins on final pathologic analysis. Statistical review revealed that initial Gleason score, PSA density, and number of positive cores at first biopsy were not predictive of men with higher volume/grade on re-biopsy. CONCLUSIONS: Immediate TRUS repeat biopsy after diagnosis frequently fails to redemonstrate prostate cancer confirming the favorable-risk nature of disease burden in this group being considered for AS. A subset of patients are upgraded (17%) leading to reconsideration of AS. We conclude this clinic-based approach provides valuable additional information to discriminate appropriate AS candidates.

Ribose sugars generate internal glycation cross-links in horse heart myoglobin.

Glycation of horse heart metmyoglobin with d-ribose 5-phosphate (R5P), d-2-deoxyribose 5-phosphate (dR5P), and d-ribose with inorganic phosphate at 37°C generates an altered protein (Myo-X) with increased SDS-PAGE mobility. The novel protein product has been observed only for reactions with the protein myoglobin and it is not evident with other common sugars reacted over a 1 week period. Myo-X is first observed at 1-2 days at 37°C along with a second form that is consistent in mass with that of myoglobin attached to several sugars. MALDI mass spectrometry and other techniques show no evidence of the cleavage of a peptide from the myoglobin chain. Apomyoglobin in reaction with R5P also exhibited this protein form suggesting its occurrence was not heme-related. While significant amounts of O(2)(-) and H(2)O(2) are generated during the R5P glycation reaction, they do not appear to play roles in the formation of the new form. The modification is likely due to an internal cross-link formed during a glycation reaction involving the N-terminus and an internal amine group; most likely the neighboring Lys133. The study shows the unique nature of these common pentose sugars in spontaneous glycation reactions with proteins.

Odour suppression in binary mixtures.

It has been suggested that odours causing stronger trigeminal activation suppress weaker trigeminal stimuli and that mixed olfactory-trigeminal stimuli suppress odorants that only activate one of these systems. Volunteer normosmic participants (n=20) were exposed to six odorants with varying trigeminal impact to test the hypothesis that more intense "trigeminal" odorants would suppress weaker trigeminal stimuli in binary odour mixtures. It was also hypothesised that stronger trigeminal odorants would dominate six-odour mixtures. The predicted linear pattern of suppression was not seen, with a quadratic model emerging from the data. Stronger trigeminal stimuli failed to dominate six-odour mixtures. Despite the fact that the major hypothesis was not supported, it can be hypothesised from this experiment that the effect of suppression in binary mixtures is reliant upon two major effects: (1) the association formed between odours and the multiple memory systems that they interact with during the encoding and recognition processes, and (2) the balance between activation of the olfactory and trigeminal systems.

The influence of training on chemosensory event-related potentials and interactions between the olfactory and trigeminal systems.

It is not possible to accurately predict the perceptual response to odorants and odorant mixtures without understanding patterns of suppression and facilitation that result from interactions between the olfactory and trigeminal systems. The current study extends previous findings by exploring the effect of intensive training on the interaction between these systems and also by using a different mixed chemosensory stimulus to examine whether the principles established in earlier studies generalize to different odorants. Stimuli were chosen so as to selectively activate the olfactory (H2S) and trigeminal (CO2) nerves. In addition, linalool was included as a stimulus that activated both systems. Thirty-five participants (19 men, 16 women) rated the intensity of each stimulus when presented both alone and in binary mixtures (linalool + H2S, and linalool + CO2). Chemosensory event-related potentials were obtained from three recording positions. Analysis of intensity ratings showed that linalool was significantly less intense than the other stimuli when presented alone. In binary mixtures, H2S was strongly suppressed by linalool. One week of intensive odor training produced significant and specific reductions in the intensity of linalool and H2S, both alone and in their mixture. Training with a different odor (champignol) had no effect. Chemosensory event-related potential data confirmed previous findings showing changes in topographical distribution that reflected the degree of trigeminal activity. Binary mixtures generally produced larger amplitudes than single stimuli. Latencies clearly differentiated between the three single stimuli and the binary mixtures. Changes were observed in event-related potentials that reflected those obtained for intensity ratings in that they were observed for linalool and H2S in the linalool trained group only. The amplitude of the late 'endogenous' component (P3) was significantly decreased for these odors at frontal recording sites. In summary, strong and specific training effects were observed in intensity ratings for participants trained with the test odor (linalool), but not for those trained with a different odor. This was supported by a significant decrease of amplitudes of the event-related potentials at frontal recording sites following training with the test odor only

Intranasal chemosensory function of the trigeminal nerve and aspects of its relation to olfaction.

OBJECTIVES: The review outlines characteristics of the intranasal trigeminal chemosensory system. In addition, it provides selective comparisons of the trigeminal and olfactory systems, the two of which interact at multiple levels. RESULTS AND CONCLUSIONS: This interaction between the trigeminal and olfactory systems is an important determinant of sensations of odor. Further, it appears to change as a result of aging and disease. Thus, the interaction between the olfactory and trigeminal systems is not straightforward and may be difficult to predict, but it has a powerful influence on the perception of odors.