Biomechanical Analysis of Headless Compression Screw Versus Tension Band Wiring for Proximal Interphalangeal Joint Arthrodesis.

PURPOSE: Proximal interphalangeal (PIP) joint arthrodesis is a procedure employed to address arthritis, instability, and deformity. Multiple fixation methods are available to maintain stability across the arthrodesis interval, including headless compression screws (HCSs), tension band wiring (TBW), plating, and Kirschner wire constructs. The purpose of this study was to compare the biomechanical properties of the HCS and TBW techniques. METHODS: Thirty-two nonthumb digits from the paired upper limbs of four fresh frozen cadavers were divided into pairs, matching contralateral digits from the same specimen. One PIP joint of each pair was fused with an antegrade 3.5 mm HCS, and the second was fused with TBW using 0.035 in. Kirschner wires with 24-gauge dental wire. Each construct was then stressed to 10 N in the radial deviation, ulnar deviation, flexion, and extension planes, and stiffness (N/mm) was calculated. The fingers were stressed to failure in extension with the ultimate load and mode of failure recorded. RESULTS: When stressed in extension, the HCS construct had a significantly greater mean stiffness than the TBW construct (16.4 N/mm vs 10.8 N/mm). The stiffness in all other planes of motion were similar between the two constructs. The mean ultimate load to failure in extension was 91.4 N for the HCS and 41.9 N for the TBW. The most common mode of failure was fracture of the dorsal lip of the proximal phalanx (13/16) for the HCS and bending of the K-wires (15/16) for TBW. CONCLUSIONS: Arthrodesis of the PIP joint using a HCS resulted in a construct that was significantly stiffer in extension with greater than double the load to failure compared to TBW. CLINICAL RELEVANCE: Although the stiffness required to achieve successful PIP joint arthrodesis has not been well quantified, the HCS proved to be the most favorable construct with respect to initial strength and stability.

Fractional Lengthening of Forearm Flexor Tendons: A Cadaveric Biomechanical Analysis.

PURPOSE: Multiple procedures have been described for wrist and finger flexion contractures and spasticity. Fractional lengthening of forearm flexor tendons involves making parallel transverse tenotomies at the musculotendinous junction to elongate the muscle. Currently, there is limited literature to define the biomechanical consequences of this lengthening technique. METHODS: Forty-eight flexor tendons were harvested from eight paired upper limbs including flexor carpi radialis, flexor carpi ulnaris, flexor pollicis longus, and flexor digitorum superficialis tendons. Each tendon that was lengthened was paired with the contralateral tendon as a control. A pair of transverse tenotomies were completed for the fractional lengthening. The first tenotomy was performed at the musculotendinous junction where the tendon narrowed to 75% of its maximal width. The second tenotomy was made 1 cm distal to the first. Tendon length was measured before and after fractional lengthening at a constant resting tension of 1 N. The maximum load at failure of each tendon and the mechanism of failure were each measured and compared with the contralateral side. RESULTS: After fractional lengthening, the mean increase in resting tendon length was 4 mm. When loaded to failure, the mean maximum load of fractionally lengthened tendons was 42% of the mean maximum load of intact tendons. All lengthened tendons failed at the distal tenotomy site. CONCLUSIONS: Fractional lengthening resulted in an increase of 3-6 mm (mean: 4 mm) in tendon length at resting tension. There was a significant loss in tensile strength and load to failure following fractional lengthening compared with an intact musculotendinous unit. CLINICAL RELEVANCE: The reduction in tensile strength following fractional lengthening results in loads at failure that are, in some cases, lower than the estimated forces required to perform basic tasks. Caution during the healing and rehabilitation period is warranted.

Evaluation of Radiographic Parameters Following Dorsal Wrist-Spanning Plate Fixation of Distal Radius Fractures to the Second Versus Third Metacarpal.

PURPOSE: Dorsal wrist-spanning plate fixation for comminuted, intra-articular distal radius fractures involves the indirect reduction of intra-articular fractures via ligamentotaxis. The reduction is maintained by application of a bridge plate from the radial diaphysis to either the second or third metacarpal. The objective of this study was to retrospectively compare radiographic outcomes between distal radius fractures managed with bridge plate fixation to the second versus third metacarpal. METHODS: A single-institution retrospective review identified 50 cases of distal radius fractures that underwent dorsal wrist-spanning plate fixation, with 9 and 41 fractures undergoing fixation to the second and third metacarpals, respectively. Radiographic parameters, such as radial height, radial inclination, volar tilt, and ulnar variance, were measured at 3 time points: immediately after surgery, immediately prior to elective plate removal, and at the final follow-up. Radiographic measurements of the 2 cohorts were compared at the 3 time points. RESULTS: Final radiographs showed an average radial height of 8.9 mm versus 9.4 mm for the second versus third metacarpal cohorts, respectively; average radial inclination of 17.4° for both the second and third metacarpal cohorts; average volar tilt of 1.9° versus 1.7° for the second versus third metacarpal cohorts, respectively; and an average ulnar variance of +0.6 mm versus +0.1 mm for the second versus third metacarpal cohorts, respectively. Radiographic parameters of the second and third metacarpal cohorts were similar across all the time points. Additionally, evaluation of the radiographic parameters across the 3 time points (immediately after surgery, immediately prior to elective plate removal, and at the final follow-up) demonstrated little to no loss of radiographic alignment. CONCLUSIONS: Radiographic outcomes for distal radius fractures managed with bridge plate fixation to the second versus third metacarpal appear similar. The distal plate fixation site can likely be determined on the basis of fracture anatomy and patient-specific features. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Are Readmission and Reoperation Rates for Lower Extremity Necrotizing Fasciitis Different Between Patients With and Without Diabetes Mellitus?

Necrotizing fasciitis is a condition associated with high morbidity and mortality unless emergent surgery is performed. This study aims to understand the hospital course of diabetic and nondiabetic patients managed for lower-extremity necrotizing fasciitis by identifying factors contributing to readmissions and reoperations. About 562 patients treated for lower-extremity necrotizing fasciitis were selected from the American College of Surgeons-National Surgical Quality Improvement Program database between 2012 and 2017. The unplanned reoperation and readmission rates for all patients during the 30-day postoperative period were 9.4% and 5.3%, respectively. Out of 562 patients with lower-extremity necrotizing fasciitis, 326 (58.0%) patients had diabetes. Diabetes patients were more likely to undergo amputation (p < .00001). Neither readmission (6.1% vs 4.2%, p = .411) nor reoperation (8.6% vs 10.6%, p = .482) were significantly different between patients with and without diabetes. Neither readmission (7.2% vs 4.0%, p = .159) nor reoperation (4.1% vs 3.7%, p = .842) were significantly different between patients undergoing amputation and nonamputation procedures. In simple logistic regression, factors associated with unplanned reoperation included poorer renal function, thrombocytopenia, longer duration of surgery, longer hospital length of stay, postoperative surgical site infection, postoperative respiratory distress, and postoperative septic shock. Body mass index >30 kg/m2 was associated with decreased odds of readmission. In multiple logistic regression, surgical site infection was the only predictor of reoperation (adjusted odds ratio 7.32, 95% confidence interval 2.76-19.1), and any amputation was associated with readmission (adjusted odds ratio 4.53, 95% confidence interval 1.20-29.6). Further study is needed to understand patient characteristics to better direct management. However, the current study elucidates patient outcomes for a relatively rare condition.

The Impact of Hospitalization for Diabetic Foot Infection on Health-Related Quality of Life: Utilizing PROMIS.

Diabetic foot infections (DFI) are an increasingly common cause of hospitalizations. Once hospitalized with DFI, many patients require some level of amputation, often undergoing multiple operations. With increasing importance on patient-centered metrics, self-reported health-related quality of life (HRQOL) tools have been developed. This prospective cohort study aimed assessed the impact of DFI on HRQOL. Two hundred twenty-four patients completed the 29-item Patient-Reported Outcome Measurement Information System (PROMIS) and 12-Item Short Form (SF-12) survey. Secondary outcomes using the Foot and Ankle Ability Measures survey were obtained and included in the analysis. The study group was comprised of hospitalized patients with DFIs (n = 120), and the control group was comprised of patients with diabetes who were evaluated for routine outpatient foot care (n = 104); diabetic foot screening, wound care, onychomycosis, and/or callosities. Using this cohort, a propensity score-matched sample of hospitalized patients with DFI (n = 35) and control group patients (n = 35) was created for comparative analysis. The 2-independent sample t test was used to test for group differences on each of the PROMIS subscale outcomes. Using PROMIS, we found that hospitalized patients with DFI reported significantly worse HRQOL in 6 of 7 subscales (physical function, anxiety, depression, fatigue, social role, pain intensity; p value range: .0001-.02) compared to outpatients with diabetes evaluated for routine foot care. There was no significant difference between the 2 groups on sleep disturbance (p = .22). Patients hospitalized for DFI report lower HRQOL compared to patients with diabetes receiving routine outpatient foot care.

Impedance Measurement System for Assessing the Barrier Integrity of Three-Dimensional Human Intestinal Organoids.

Human pluripotent stem cell (hPSC)-derived intestinal organoids (HIOs) hold unprecedented promise for basic biology and translational applications. However, developing a quantitative method to evaluate the epithelial cell membrane integrity of HIOs as an in vitro intestinal barrier model is a major challenge because of their complex three-dimensional (3D) structure. In this study, we developed an impedance system to measure the change in electrical resistance of 3D HIOs depending on the integrity of the intestinal epithelial cell membrane, which can reflect functionality and maturity. The expression of intestinal maturation- and tight junction-related markers was significantly higher in HIOs matured in vitro by treatment with IL-2 than in control HIOs. Analysis of gap junction size indicated that mature HIOs have greater integrity, with approximately 30% more compact gaps than immature HIOs. We designed a multi-microchannel system controlled by the inhalation pressure where the HIO is loaded, which enhances the stability and sensitivity of the impedance signal. We demonstrated the applicability of the impedance system by showing the difference in resistance between control and mature HIOs, reflecting the expression of tight junction proteins and their maturation status. We also validated the impedance system by monitoring its resistance in real time during junctional damage to HIOs induced by a digestive agent. In summary, we suggest a quantitative method to directly quantify the physiological changes in complex 3D organoid structures based on impedance spectroscopy, which can be applied to noninvasively monitor live cells and therefore enable their use in subsequent experiments.

Systematic review and network meta-analysis of subscapularis management techniques in anatomic total shoulder arthroplasty.

BACKGROUND: Controversy exists regarding the optimal subscapularis management technique in patients undergoing anatomic total shoulder arthroplasty. The purpose of this study was to compare clinical, radiographic, and functional outcomes between subscapularis tenotomy (ST), lesser tuberosity osteotomy (LTO), and subscapularis peel (SP) techniques. METHODS: We performed a level III systematic review and network meta-analysis comparing ST, LTO, and SP in patients undergoing anatomic total shoulder arthroplasty. Our primary collection endpoints included range of motion, subscapularis function, subscapularis healing, functional patient-reported outcomes, complications, and revision surgery. Data were pooled and network meta-analysis was performed owing to the comparison of 3 groups. RESULTS: Eight studies met our inclusion criteria for meta-analysis. There was no difference in sex or primary diagnosis between the 3 cohorts. No significant difference was found in postoperative external rotation or forward flexion between the groups. Meta-analysis found the SP cohort to have significantly greater internal rotation strength than the ST cohort. The belly-press test results were negative most commonly in the LTO group, and there was a significant difference compared with the ST or SP group (P < .0001). The weighted-mean healing rate for the LTO site was 98.9% on radiographic imaging. There was a significantly higher ultrasound healing rate in the LTO cohort than in the ST and SP cohorts. All groups had good postoperative patient-reported outcome scores (average American Shoulder and Elbow Surgeons score range, 78.6-87) and a relatively low rate of complications (3%). CONCLUSION: This network meta-analysis demonstrates that the LTO group has superior healing and postoperative subscapularis-specific physical examination test results compared with the ST and SP groups. However, no difference in postoperative range of motion was found between the groups, and all techniques demonstrated good functional patient-reported outcomes, with a low rate of postoperative complications. These findings provide evidence-based support that ST, SP, and LTO all demonstrate similar outcomes; therefore, selection should be based on surgeon experience and comfort.

Postoperative Outcomes in Diabetic Pediatric Orthopaedic Surgery Patients: A National Database Study.

BACKGROUND: Although the negative effects of diabetes mellitus (DM) on operative outcomes in orthopaedic surgery is a well-studied topic in adults, little is known about the impact of this disease in children undergoing orthopaedic procedures. This study aims to describe the postoperative complications in pediatric orthopaedic surgery patients with DM. METHODS: Pediatric patients with insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM) were retrospectively identified while selecting for elective orthopaedic surgery cases from the American College of Surgeons National Surgical Quality Improvement Program Pediatric (ACS-NSQIP-Pediatric) database from 2012 to 2015. Univariate and multivariate analyses were performed to describe and assess outcomes when compared with nondiabetic patients undergoing similar procedures. RESULTS: Of the 17,647 patients identified, 105 (0.60%) had DM. Of those 105 patients, 68 had IDDM and 37 had NIDDM. The median age of DM patients was 13.8 years (11.9 to 15.5 y) and 37.1% of all DM patients were male. Comparing DM to non-DM patients, no significant differences were noted in the overall complications (1.4% vs. 1.9%, P>0.05) or reoperation rates (1.2% vs. 1.9%, P>0.05); however, DM patients did have a higher occurrence of unplanned readmissions (4.8% vs. 1.7%; P=0.037). Diabetic patients were statistically more likely to have an unplanned readmission with 30 days (adjusted odds ratio=3.34; 95% confidence interval=1.21-9.24, P=0.021). when comparing IDDM to NIDDM, there was no significant difference in outcomes. Comparing NIDDM to non-DM patients, there was an increased incidence of nerve injury (5.6% vs. 0.18%; P=0.023), readmission rate (11.1% vs. 1.8%; P=0.043), and reoperation rate (11.1% vs. 1%; P=0.013) in nonspinal procedures and an increased incidence of pulmonary embolism (10% vs. 0%; P=0.002) in spinal arthrodesis procedures. NIDDM predicted longer hospital stays (adjusted odds ratio=1.49; 95% confidence interval=1.04, 2.14; P=0.028) compared with nondiabetic patients in extremity deformity procedures. CONCLUSIONS: The 30-day complication, reoperation, and readmission rates for NIDDM patients were higher than that of non-DM patients. Furthermore, NIDDM is a predictor of longer hospital stays while DM is a predictor of unplanned readmissions. No statistical differences were noted when comparing outcomes of NIDDM to IDDM patients. LEVEL OF EVIDENCE: Level III.

Insulin Dependence Increases the Risk of 30-Day Postoperative Complications Following Ankle Fracture Surgery in Patients With Diabetes Mellitus.

Patients with diabetes mellitus that undergo ankle fracture surgery have higher rates of postoperative complications compared to patients without diabetes mellitus. We evaluated the rate of complications in insulin-dependent diabetes mellitus patients, non-insulin-dependent diabetes mellitus patients, and patients without diabetes in the 30-day postoperative period following ankle fracture surgery. We also analyzed hospital length of stay, unplanned readmission, unplanned reoperation, and death. Patients who underwent operative management for ankle fractures between 2012 and 2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program® database using Current Procedural Terminology codes. Multiple logistic regression was implemented. Adjusted odds ratios were calculated along with the 95% confidence interval. A total of 19,547 patients undergoing ankle surgery were identified from 2012 to 2016. Of these patients, 989 (5.06%) had insulin-dependent diabetes mellitus, 1256 (6.43%) had noninsulin-dependent diabetes mellitus, and 17,302 (88.51%) did not have diabetes mellitus. Compared to patients without diabetes, patients with insulin-dependent diabetes mellitus had significantly greater adjusted odds of superficial surgical site infections, deep surgical site infections, osteomyelitis, wound dehiscence, pneumonia, unplanned intubation, mechanical ventilation, urinary tract infection, cardiac arrest, bleeding requiring transfusion, sepsis, hospital length of stay, unplanned readmission, unplanned reoperation, and death following ankle fracture surgery. We demonstrate that insulin-dependent diabetes mellitus is a strong predictor of 30-day postoperative complications, unplanned readmission, unplanned reoperation, and death following ankle fracture surgery.

Short Term Radiographic and Patient Outcomes of a Biplanar Plating System for Triplanar Hallux Valgus Correction.

Hallux valgus is a complex deformity with a variety of techniques described for correction. A biplanar plating system for triplanar correction system has been developed to address both the translation and rotational component of the hallux valgus deformity and allow an accelerated weightbearing protocol. The purpose of this study was to determine the correction and complications using radiographic parameters and patient reported outcomes. We sought to determine prognostic factors for successful correction, including age, gender, and preoperative deformity. From the medical records, we collected preoperative data. Patient-reported outcomes were obtained using AOFAS Hallux Metatarsophalangeal-Interphalangeal score, FAAM, and SF-12 scores preoperatively and postoperatively. Imaging was reviewed at preoperative and postoperative visits to determine hallux valgus angle, intermetatarsal angle, and tibial sesamoid position. Fifty-seven procedures, in 55 patients, were performed. There were 7 complications and mean follow-up time was 45.7 weeks (+ 28.3 weeks). Age over 62.5 years were associated with an increased risk of complications (p = .018). Males had an increased rate of complications (71%) compared with females. Radiographic parameters were significantly improved from preoperative values at alltime points (p < .05). Only the AOFAS Hallux Metatarsophalangeal-Interphalangeal score was statistically significant at 3, 6 and 12 months. We sought to determine the effectiveness of biplanar plating and triplanar correction procedure with early weightbearing. Over a 12 month follow-up period, our results showed significant improvement in deformity and maintained correction. AOFAS Hallux Metatarsophalangeal-Interphalangeal scores significantly improved from the preoperative to the postoperative state. Our results show a nonunion rate of 5.2%, which is comparable to prior studies.

The Infected Diabetic Foot: Re-evaluating the Infectious Diseases Society of America Diabetic Foot Infection Classification.

BACKGROUND: We provide evidence to revise the Infectious Diseases Society of America (IDSA) diabetic foot infection classification by adding a separate tier for osteomyelitis and evaluating if moderate and severe infection criteria improve the classification's ability to direct therapy and determine outcomes. METHODS: We retrospectively evaluated 294 patients with moderate and severe infections. Osteomyelitis was confirmed by bone culture or histopathology. Soft tissue infection (STI) was based on negative bone culture, magnetic resonance imaging, or single-photon emission computed tomography. We stratified STI and osteomyelitis using IDSA criteria for moderate and severe infections and compared outcomes and complications. RESULTS: Osteomyelitis patients had greater antibiotic duration (32.5 ± 46.8 vs 63.8 ± 55.1 days; P < .01), surgery frequency (55.5% vs 99.4%; P < .01), number of surgeries (2.1 ± 1.3 vs 3.3 ± 2.3; P < .01), amputations (26.3% vs 83.4%; P < .01), reinfection (38.0% vs 56.7%; P < .01), and length of stay (14.5 ± 14.9 vs 22.6 ± 19.0 days; P < .01). There were no differences in moderate and severe STI outcomes except for infection readmissions (46.2% vs 25.0%; P = .02), and acute kidney injury (31.2% vs 50.0%; P = .03). There were no differences in moderate and severe osteomyelitis except the number of surgeries (2.8 ± 2.1 vs 4.1 ± 2.5; P < .01) and length of stay (18.6 ± 17.5 vs 28.2 ± 17.7; P < .01). CONCLUSIONS: The IDSA classification better reflects outcomes if risk categories are stratified by STI or osteomyelitis and moderate and severe infections are not categorized separately.

The infected diabetic foot: Can serum biomarkers predict osteomyelitis after hospital discharge for diabetic foot infections?

The aim of this study is to evaluate serum biomarkers to monitor high-risk patients for reinfection of bone. Thirty-five patients were prospectively enrolled with moderate to severe diabetic foot infections with suspicion of osteomyelitis. Bone samples were obtained for culture and histology. Clinical characteristics and outcomes of patients were compared using χ2 square test. Biomarkers (white blood cell count, erythrocyte sedimentation rate, c-reactive protein, procalcitonin, interleukin-6, interleukin-8, and monocyte chemoattractant protein 1) were assessed at baseline, 3, and 6 weeks after treatment initiation and evaluated for correlation with reinfection of bone. After 6 weeks of antibiotic treatment, ESR at 73.5 mm/h (sensitivity 62.5%, specificity 100%, area under the receiver operating characteristic (AUROC) 0.7839, 95% CI 0.54-1.00, P < .01) and IL-8 at 15.09 mg/dL (sensitivity 42.9%, specificity 92.0% AUROC 0.6286, 95% CI 0.36-0.90, P = .0496) were associated with reinfection of bone. An increase in IL-8 from week 0 to 6 >0.95 mg/dL was associated with reinfection (sensitivity 71%, specificity 72% AUROC 0.7057, 95% CI 0.49-0.92, P = .04). An ESR change from week 0-6 of -16.5% (sensitivity 71.4%, specificity 86.4% AUROC 0.7403, 95% CI 0.48-1.00, P = .02), CRP (-)74.4% (sensitivity 66.7%, specificity 91.3% AUROC 0.7174, 95% CI 0.40-1.00, P = .04), IL-6 (-)49.9% (sensitivity 71.4%, specificity 76% AUROC 0.7371, 95% CI 0.47-1.00, P = .04), and IL-8 29% (sensitivity 85.7%, specificity 56.0% AUROC of 0.7343, 95% CI 0.54-0.93, P = .048) were associated with increased risk of reinfection. Pilot data suggest that serum biomarkers (ESR, IL8 and IL6, MCP-1) may be correlated with developing osteomyelitis and could be used to monitor high-risk patients for reinfection.

Charcot Midfoot Reconstruction: Does Subtalar Arthrodesis or Medial Column Fixation Improve Outcomes?

Charcot neuroarthropathy is a complication of neuropathy often secondary to diabetes mellitus and most commonly affects the midfoot. In these patients, reconstruction of the foot may be required for limb salvage. A superconstruct technique has previously been described using intramedullary beaming fixation of the midfoot and hindfoot to span the zone of injury. Inclusion of the subtalar joint in the arthrodesis construct is not consistently performed among different surgeons. The aim of this study was to describe midfoot beaming constructs and postoperative complications after midfoot reconstruction with and without subtalar arthrodesis. We reviewed medical records of patients who underwent midfoot Charcot reconstruction with an intramedullary beaming superconstruct. Patients included in the study had at least 3 months of follow-up and had Sanders-Frykberg II/III classification of Charcot neuroarthropathy. Postoperative radiographs were evaluated for evidence of hardware failure at the latest follow-up evaluation. The main variables of interest were: hardware failure or nonunion requiring revision operation, deep infection, and unplanned reoperation. Thirty patients who underwent midfoot reconstruction were included. The mean follow-up was 67.4 ± 25.9 weeks. Twenty-two (73.3%) patients had concomitant subtalar arthrodesis and midfoot beaming. Overall complications were lower in patients with subtalar arthrodesis (40.9%) than those without subtalar arthrodesis (75%) resulting in an odds ratio of 0.271 (0.042-1.338, p = .146). Furthermore, increased number of screws used in the midfoot construct was negatively correlated with complications (r = -0.44, p = .01). An intramedullary midfoot beaming superconstruct with subtalar arthrodesis has previously been proposed to provide better fixation after midfoot beaming Charcot neuroarthropathy reconstruction. Our results suggest including the subtalar joint as part of a superconstruct for the reconstruction of Sanders-Frykberg II/III Charcot results in an 80% lower complication rate than intramedullary beaming alone. We also found an increased number of screws used in the midfoot results in a lower complication rate.

Colorimetric Detection of UO2+2 Using Gold Nanoparticles Immobilized with Pillar[5]arene Complexes with Nitrophenyldiacetic Acids as a Chemoprobe.

Uranium is a crucial raw material in the nuclear energy industry; however, its radioactive nature makes it a critically damaging component to both the atmosphere and human health. In this study, we report a simple and cost-effective selective colorimetric detection technique for UO2+2 using nitrophenyldiacetic acids (NPD)-functionalized gold nanoparticles (Au NPs 1). The hybrid Au NPs 1 can be induced to aggregate in the presence of UO2+2 ions. UO2+2 can be recognized by the colorimetric response of hybrid Au NPs 1, which can be observed by a UV-Vis spectrophotometer and it is easily detectable by the naked eye. The hybrid Au NPs 1 bound by UO2+2 possess a good selective response compared to other metal ions (Li+, Na+, K+, Rb+, Cs+, Ca2+, Mg2+, Ba2+, Ni2+, Zn2+, and Co2+), which can be observed by a prominent color change. The color of the hybrid Au NPs 1 changed from red to dark red upon addition of UO2+2 in the presence of other metal ions. Job's plot demonstrates that one NPD moiety attached onto the surface of Au NPs 1 forms 1:1 stoichiometry with UO2+2, hence providing a simple and effective colorimetric sensor for the real-time detection of UO2+2.

What are the Optimal Cutoff Values for ESR and CRP to Diagnose Osteomyelitis in Patients with Diabetes-related Foot Infections?

BACKGROUND: Distinguishing osteomyelitis from soft-tissue infection of the foot is important because osteomyelitis is associated with more operations, amputation, and prolonged antibiotic exposure. Both erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are routinely ordered inflammatory biomarkers for evaluating foot infection. When initial evaluation is inconclusive, advanced imaging is indicated, and high clinical or radiographic suspicion of osteomyelitis may indicate bone biopsy to identify organisms and antibiotic sensitivity. Although ESR and CRP levels are helpful for distinguishing osteomyelitis from soft-tissue infections in patients with diabetes-related foot infections, parameters regarding optimal cutoff values for those tests have not, to our knowledge, been defined. QUESTIONS/PURPOSES: (1) What are the optimal cutoff values for ESR and CRP to differentiate osteomyelitis from soft-tissue infection in patients with diabetes-related foot infection? (2) Can a diagnostic algorithm be derived to guide interpretation of ESR and CRP to improve recognition of osteomyelitis in the setting of diabetic foot infection? METHODS: The medical records of 1842 patients between 18 and 89 years of age treated at our institution between January 1, 2010 and February 6, 2017 for foot infection were reviewed. For inclusion, patients must have had a diagnosis of diabetes mellitus, moderate or severe infection, ESR and CRP values within 72 hours of admission, either advanced imaging (MRI or single-positron emission computed tomography/computed tomography [SPECT/CT]) or bone biopsy during admission and must not have had comorbidities that could affect ESR and CRP, such as autoimmune disorders. As such, 1489 patients were excluded, and 353 patients were included in the study. Osteomyelitis was diagnosed by positive bone culture or histopathology. Osteomyelitis was considered to be absent if there was a negative MRI or SPECT/CT result, or negative bone culture and histology findings if imaging was inconclusive. We identified 176 patients with osteomyelitis and 177 with soft-tissue infection. A blinded investigator performed the statistics. Optimal cutoffs of ESR and CRP were determined using receiver operative characteristic (ROC) analysis. A diagnostic algorithm was determined using epidemiologic principles of screening evaluations. RESULTS: An ESR of 60 mm/h and a CRP level of 7.9 mg/dL were determined to be the optimal cutoff points for predicting osteomyelitis based on results of the ROC analysis. The ESR threshold of 60 mm/h demonstrated a sensitivity of 74% (95% confidence interval [CI], 67-80) and specificity of 56% (95% CI, 48-63) for osteomyelitis, whereas the CRP threshold of 7.9 mg/dL had a sensitivity of 49% (95% CI, 41-57) and specificity of 80% (95% CI, 74-86). If the ESR is < 30 mm/h, the likelihood of osteomyelitis is low. However, if ESR is > 60 mm/h and CRP level is > 7.9 mg/dL, the likelihood of osteomyelitis is high, and treatment of suspected osteomyelitis should be strongly considered. CONCLUSIONS: While ESR is better for ruling out osteomyelitis initially, CRP helps distinguish osteomyelitis from soft-tissue infection in patients with high ESR values. Further prospective studies addressing the prognostic value of ESR and CRP are needed, and a more comprehensive diagnostic algorithm should be developed to include other diagnostic tests such as probe-to-bone and imaging. LEVEL OF EVIDENCE: Level III, diagnostic study.

Acetabular Protrusio in Patients With Osteogenesis Imperfecta: Risk Factors and Progression.

BACKGROUND: Osteogenesis imperfecta (OI) is a genetic disorder commonly associated with osteopenia, osteoporosis, bone fractures, bone deformities, and other clinical features. A frequent radiologic finding with OI is acetabular protrusio (AP). We hypothesized that AP develops in patients with OI over time. In addition, we hypothesized that AP also develops in patients with OI without radiographic evidence of AP on initial examination. METHODS: Medical records and radiographs of 55 patients (109 hips) diagnosed with OI evaluated at our institution were retrospectively reviewed. Previously established radiographic criteria using the center-edge (CE) angle of Wiberg, position of the acetabulum relative to the iliopectineal line, crossing of the acetabulum across the ilioischial (Kohler) line, and position of the teardrop figure relative to the ilioischial (Kohler) line were utilized to assess AP severity. In addition, pharmacological treatments and patient factors including body mass index (BMI) were recorded. Radiographs of patients with OI that were taken ≥2 years apart were analyzed utilizing AP radiographic criteria to assess for changes. The changes in AP-related measurements were standardized by distance or degree per year. In addition, patient factors were evaluated for associations with AP development. RESULTS: In this series of 109 hips (55 patients), incidence of AP in earliest radiographs was 45% (49/109). Patients with OI type I and III demonstrated the highest incidence of AP (65%). Among the hips that did not meet the criteria for AP in their early radiographs, 24 (40%) were positive for AP by their latest radiograph. In the hips that initially presented with AP, 42% showed increased CE angles on later radiographs. Twenty-six hips (24%) showed either no observable changes or reduced CE angles. Risk factors that were significantly associated with greater odds of developing AP included (1) an age under 12; (2) a BMI>25; (3) presence of AP of the contralateral hip; and (4) female sex. Bisphosphonates, vitamin D, physical therapy, and other drugs related to treatment of OI reduced the risk of developing AP but did not achieve statistical significance. CONCLUSIONS: AP is a common finding in OI patients (54%). Among hips of OI patients that met criteria for AP in early radiographs, 42% (20/48) demonstrated greater CE angles in their latest radiographs. Similar changes were observed in OI patients who did not initially meet criteria for diagnosis for AP. However, CE angle measurements between the 2 groups did not significantly differ (P=0.71). In terms of Kohler line crossing, patients that met criteria for AP in early radiographs had significantly greater change per year than those that did not have AP criteria (P<0.05). The findings suggest AP may develop over time in patients with OI and may be influenced by patient factors such as age, sex, and BMI. In addition, unilateral AP may have a significant impact on the development of AP of the contralateral hip. LEVEL OF EVIDENCE: Level IV-retrospective case series.

Increased Rates of Readmission, Reoperation, and Mortality Following Open Reduction and Internal Fixation of Ankle Fractures Are Associated With Diabetes Mellitus.

The purpose of this study was to compare the rates of readmission, reoperation, and mortality in patients with and without diabetes mellitus during the 30-day postoperative period after ankle fracture surgery. Patients who underwent operative management for ankle fractures between 2006 and 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program® database by using Current Procedural Terminology codes for ankle fracture surgery. A total of 17,464 patients undergoing ankle fracture surgery were identified. Of these patients, 2044 (11.7%) had diabetes and 15,420 (88.3%) did not have diabetes. We excluded patients older than 90 years or with inadequate perioperative data. Patients with diabetes had significantly higher rates of readmission (2.84% vs 1.05%, p < .0001), significantly higher rates of unplanned reoperation (2.3% vs 0.74%, p < .0001), and significantly higher rates of mortality (0.7% vs 0.2%, p < .0001) compared with patients without diabetes. Additionally, patients with diabetes had significantly greater age-adjusted odds ratios (ORs) of unplanned readmission (OR 2.40, 95% confidence interval [CI] 1.74 to 3.31, p < .0001), unplanned reoperation (OR 2.56, 95% CI 1.44 to 3.27, p < .0001), and mortality (OR 2.01, 95% CI 1.08 to 3.62, p = .0432) than did patients without diabetes after ankle surgery. In this large-scale retrospective study, we demonstrated that the presence of diabetes significantly increases the risk of unplanned readmission, unplanned reoperation, and mortality during the 30-day postoperative period after ankle fracture surgery.

Diagnostic Utility of Erythrocyte Sedimentation Rate and C-Reactive Protein in Osteomyelitis of the Foot in Persons Without Diabetes.

The aim of the study was to assess the diagnostic value of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels in differentiating foot osteomyelitis (OM) from soft tissue infection (STI) in persons without diabetes. We evaluated 102 patients in a retrospective cohort study of nondiabetic patients admitted to our institution with OM (n = 51) and with STI (n = 51). Patient diagnosis was determined through bone culture and/or histopathology for OM and magnetic resonance scan and/or single-photon emission computed tomography for STI. Cutoffs for ESR and CRP to predict OM as identified by receiver operating characteristic were 45.5 mm/h and 3.45 mg/dL, respectively. The ESR cutoff demonstrated a sensitivity and specificity of 49% and 79%, while the values for CRP were 45% and 71%, respectively. The combined sensitivity and specificity for ESR and CRP were 33% and 84%. The positive and negative predictive values were 68% and 60% for ESR and 61% and 56% for CRP, respectively. In conclusion, ESR and CRP demonstrate poor sensitivity and specificity for detecting OM in the nondiabetic foot. These markers have little diagnostic utility in the nondiabetic foot.

A liver-specific gene expression panel predicts the differentiation status of in vitro hepatocyte models.

Alternative cell sources, such as three-dimensional organoids and induced pluripotent stem cell-derived cells, might provide a potentially effective approach for both drug development applications and clinical transplantation. For example, the development of cell sources for liver cell-based therapy has been increasingly needed, and liver transplantation is performed for the treatment for patients with severe end-stage liver disease. Differentiated liver cells and three-dimensional organoids are expected to provide new cell sources for tissue models and revolutionary clinical therapies. However, conventional experimental methods confirming the expression levels of liver-specific lineage markers cannot provide complete information regarding the differentiation status or degree of similarity between liver and differentiated cell sources. Therefore, in this study, to overcome several issues associated with the assessment of differentiated liver cells and organoids, we developed a liver-specific gene expression panel (LiGEP) algorithm that presents the degree of liver similarity as a "percentage." We demonstrated that the percentage calculated using the LiGEP algorithm was correlated with the developmental stages of in vivo liver tissues in mice, suggesting that LiGEP can correctly predict developmental stages. Moreover, three-dimensional cultured HepaRG cells and human pluripotent stem cell-derived hepatocyte-like cells showed liver similarity scores of 59.14% and 32%, respectively, although general liver-specific markers were detected. CONCLUSION: Our study describes a quantitative and predictive model for differentiated samples, particularly liver-specific cells or organoids; and this model can be further expanded to various tissue-specific organoids; our LiGEP can provide useful information and insights regarding the differentiation status of in vitro liver models. (Hepatology 2017;66:1662-1674).

Transfer and Dynamic Inversion of Coassembled Supramolecular Chirality through 2D-Sheet to Rolled-Up Tubular Structure.

Transfer and inversion of supramolecular chirality from chiral calix[4]arene analogs (3D and 3L) with an alanine moiety to an achiral bipyridine derivative (1) with glycine moieties in a coassembled hydrogel are demonstrated. Molecular chirality of 3D and 3L could transfer supramolecular chirality to an achiral bipyridine derivative 1. Moreover, addition of 0.6 equiv of 3D or 3L to 1 induced supramolecular chirality inversion of 1. More interestingly, the 2D-sheet structure of the coassembled hydrogels formed with 0.2 equiv of 3D or 3L changed to a rolled-up tubular structure in the presence of 0.6 equiv of 3D or 3L. The chirality inversion and morphology change are mainly mediated by intermolecular hydrogen-bonding interactions between the achiral and chiral molecules, which might be induced by reorientations of the assembled molecules, confirmed by density functional theory calculations.