Self-induced Hot Water Finger Burn Trying to Get Feeling Back after Ropivacaine Block.

This case report is about a patient with self-induced hot water burns several hours after an infraclavicular block with ropivacaine for a scaphoid fracture operation. This patient was honest about what happened. However, some patients are too embarrassed to admit what they did to themselves. The injury may be misdiagnosed by the emergency department physician or by the surgeon because the history is incomplete. The resulting burn, which can lead to fingertip loss when severe, can be erroneously misdiagnosed as an ischemic injury after lidocaine with epinephrine local anesthesia. Most hand surgeons have seen ischemic finger injuries the morning after failed finger replantation. Acutely ischemic fingers from arterial insufficiency do not have parallel hot water burn lines, reactive hyperemia at the base of the burn, or burn blisters at the fingertips. The purpose of this article and its video is to help physicians and nurses recognize the three signs of self-induced hot water finger burns after local anesthesia: (1) a parallel hot water line in the fingers at the proximal burn level; (2) reactive hyperemia just proximal to the burn line; (3) burn blisters in the submerged fingertips. When seeing postoperative patients with these signs, the examining clinician may tactfully ask: "Did you try to get the feeling back in your fingers by warming them?" It is hoped that the patient may then reveal that he tried warming the finger in water, and that may lead to the truth that the water was indeed too hot.

Secondary Bony Defects after Soft Tissue Reconstruction in Limb-Threatening Lower Extremity Injuries: Does the Approach to Flap Elevation Matter?

BACKGROUND: Limb-threatening lower extremity injuries often require secondary bone grafting after soft tissue reconstruction. We hypothesized that there would be fewer wound complications when performing secondary bone grafting via a remote surgical approach rather than direct flap elevation. METHODS: A retrospective cohort study was performed at a single Level 1 trauma center comparing complications after secondary bone grafting in patients who had undergone previous soft tissue reconstruction after open tibia fractures between 2006 and 2020. Comparing bone grafting via a remote surgical incision versus direct flap elevation, we evaluated wound dehiscence requiring return to the operating room as the primary outcome. Secondary outcomes were deep infection and delayed amputation. RESULTS: We identified 129 patients (mean age: 40 years, 82% male) with 159 secondary bone grafting procedures. Secondary bone grafting was performed via a remote surgical approach in 54% (n = 86) and direct flap elevation in 46% (n = 73) of cases. Wound dehiscence requiring return to the operating room occurred in one patient in the flap elevation group (1%) and none of the patients in the remote surgical approach. The odds of deep wound infection (OR, 1.77; p = 0.31) or amputation (OR, 1.43; p = 0.73) did not significantly differ between surgical approaches. No significant differences were found in complications between the reconstructive surgeon elevating and re-insetting the flap and the orthopaedic trauma surgeon performing the flap elevation and re-inset. CONCLUSION: Direct flap elevation for secondary bone grafting after soft tissue reconstruction for open tibia fractures did not result in more complications than bone grafting via a remote surgical approach. These findings should reassure surgeons to allow other clinical factors to influence the surgical approach for bone grafting.

What Outcomes Are Most Important to Patients Following a Lower Extremity Limb-threatening Injury?

OBJECTIVE: To determine what outcomes are most important to patients after a limb-threatening injury, and if those preferences vary based on the patients' treatment (salvage vs amputation), health, demographics, or time since injury. BACKGROUND: The preferences that motivate the patients' choice of treatment following a limb-threatening injury are poorly understood. Discrete choice experiments (DCEs) are a robust survey methodology to quantify preferences. METHODS: Patients with a history of traumatic limb-threatening injury, January 2010 to December 2020, completed a survey with our DCE and the Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaire. The DCE attributes included recovery time, function, appearance, cost, and time in hospital. We used conditional logit modeling to estimate the relative importance of each attribute on a scale of 0% to 100%, determine willingness to pay for improvements in the included attributes, and assess variation in preferences based on patient characteristics, including PROMIS score. RESULTS: A total of 150 patients completed the survey (104 limb salvage, 46 amputation; mean age, 48±16 years; 79% male). Regaining preinjury function [relative importance=41%; 95% confidence interval (CI), 37%-45%] and minimizing costs (24%; 95% CI, 21%-28%) were of greatest importance. Changes in appearance were least important (7%; 95% CI, 5%-9%). The hierarchy of preferences did not vary between those who had limb salvage or amputation, but patient age, physical and mental health, and income were associated with preference variation. CONCLUSIONS: Patients with limb-threatening injuries most valued gains in function and reduced out-of-pocket costs.

Association of Radial Head Fracture Treatment With Long-Term Function.

BACKGROUND: Radial head fractures are often associated with poor outcomes. Both open reduction and internal fixation (ORIF) and radial head arthroplasty (RHA) might be considered in operative cases. This study aimed to compare long-term patient-reported functional outcomes among patients with operatively treated radial head fractures. METHODS: A cross sectional study conducted at a Level I trauma center was used to identify patients with a radial head fracture who underwent ORIF or RHA between 2006 and 2018, and agreed to complete a survey in 2020. The primary outcome measure was the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score. RESULTS: Seventy-six patients participated in the study. No significant differences in outcomes were observed between groups. QuickDASH scores were similar for both groups (ORIF: mean = 15.7, SD = 18.4; RHA: mean = 22.8, SD = 18.6; mean difference = 0.2 [-9.0 to 9.3], P = .97). Nineteen (37%) ORIF patients and 12 (48%) RHA patients reported a need for pain medication (adjusted odds ratio [OR] = 0.8 [0.3-2.4], P = .70). Thirteen (25%) ORIF patients and 6 (24%) RHA patients required additional surgery (adjusted OR = 1.7 [0.5-6.2], P = .39). A subgroup analysis of multi-fragmentary fractures revealed similar findings. CONCLUSION: Patient-reported outcomes, which included a subgroup analysis of multi-fragmentary fractures, were similar between ORIF and RHA groups at an average of 7.5 years from surgery. Reconstructing the radial head might not result in worse outcomes than RHA when both options are employed according to the best judgment of the operating surgeon.

Lack of Vesicular Zinc Does Not Affect the Behavioral Phenotype of Polyinosinic:Polycytidylic Acid-Induced Maternal Immune Activation Mice.

Zinc is important in neural and synaptic development and neuronal transmission. Within the brain, zinc transporter 3 (ZnT3) is essential for zinc uptake into vesicles. Loss of vesicular zinc has been shown to produce neurodevelopmental disorder (NDD)-like behavior, such as decreased social interaction and increased anxiety- and repetitive-like behavior. Maternal immune activation (MIA) has been identified as an environmental factor for NDDs, such as autism spectrum disorders (ASDs) and schizophrenia (SZ), in offspring, which occurs during pregnancy when the mother's immune system reacts to the exposure to viruses or infectious diseases. In this study, we investigated the interaction effect of a genetic factor [ZnT3 knockout (KO) mice] and an environmental factor (MIA). We induced MIA in pregnant female (dams) mice during mid-gestation, using polyinosinic:polycytidylic acid (polyI:C), which mimics a viral infection. Male and female ZnT3 KO and wild-type (WT) offspring were tested in five behavioral paradigms: Ultrasonic Vocalizations (USVs) at postnatal day 9 (P9), Open Field Test, Marble Burying Test, three-Chamber Social Test, and Pre-pulse Inhibition (PPI) in adulthood (P60-75). Our results indicate that loss of vesicular zinc does not result in enhanced ASD- and SZ-like phenotype compared to WT, nor does it show a more pronounced phenotype in male ZnT3 KO compared to female ZnT3 KO. Finally, MIA offspring demonstrated an ASD- and SZ-like phenotype only in specific behavioral tests: increased calls emitted in USVs and fewer marbles buried. Our results suggest that there is no interaction between the loss of vesicular zinc and MIA induction in the susceptibility to developing an ASD- and SZ-like phenotype.

Couple and family interventions for high mortality health conditions: A strategic review (2010-2019).

The earliest publications in the field of marriage and family therapy introduced interventions conducted with families experiencing complex health conditions. This strategic review captures an evaluation of efficacy for 87 couple and family interventions published between 2010 and 2019 with a focus on the leading causes of mortality in the United States. These health conditions include chromosomal anomalies and accidents with infants aged 0-4 years; accidents and cancer among children aged 5-14; accidents among adolescents aged 15-24; and heart disease, cancer, accidents, chronic lower respiratory diseases, stroke, Alzheimer's disease, diabetes, influenza/pneumonia, and nephritis/nephrosis among adults 25 and older. Results support the need for greater inclusion of couples and families in assessments and interventions. The greatest chasm in efficacy research was with minoritized couples and families. Implications include ways to initiate couple and family interventions in the context of health conditions with attention given to accessibility, recruitment, retention, and evaluation.

Presentation and aetiology of paediatric trigger finger: a systematic review.

Paediatric trigger finger is a rare condition distinct from paediatric trigger thumb and adult trigger digits. We performed a systematic review of paediatric trigger finger presentation and aetiology in order to guide workup and management. Fifty-one studies with 193 patients and 398 trigger fingers were included. Most patients had a single, unilateral trigger finger (54%). Fifty-five patients (29%) had an underlying condition, such as mucopolysaccharidosis; these cases appeared to be associated with multiple or bilateral trigger fingers or with carpal tunnel syndrome. All patients with mucopolysaccharidosis were treated surgically. Conservative management was reported in 33% of all patients, and two-thirds of these did not need further intervention. Patients undergoing surgical release infrequently had recurrence of triggering (6%). We propose an algorithmic approach for patients presenting with paediatric trigger finger. Presence of bilateral or multiple trigger digits or concomitant carpal tunnel syndrome should raise suspicion for an atypical underlying pathology.

A simple and robust method for automating analysis of naïve and regenerating peripheral nerves.

BACKGROUND: Manual axon histomorphometry (AH) is time- and resource-intensive, which has inspired many attempts at automation. However, there has been little investigation on implementation of automated programs for widespread use. Ideally such a program should be able to perform AH across imaging modalities and nerve states. AxonDeepSeg (ADS) is an open source deep learning program that has previously been validated in electron microscopy. We evaluated the robustness of ADS for peripheral nerve axonal histomorphometry in light micrographs prepared using two different methods. METHODS: Axon histomorphometry using ADS and manual analysis (gold-standard) was performed on light micrographs of naïve or regenerating rat median nerve cross-sections prepared with either toluidine-resin or osmium-paraffin embedding protocols. The parameters of interest included axon count, axon diameter, myelin thickness, and g-ratio. RESULTS: Manual and automatic ADS axon counts demonstrated good agreement in naïve nerves and moderate agreement on regenerating nerves. There were small but consistent differences in measured axon diameter, myelin thickness and g-ratio; however, absolute differences were small. Both methods appropriately identified differences between naïve and regenerating nerves. ADS was faster than manual axon analysis. CONCLUSIONS: Without any algorithm retraining, ADS was able to appropriately identify critical differences between naïve and regenerating nerves and work with different sample preparation methods of peripheral nerve light micrographs. While there were differences between absolute values between manual and ADS, ADS performed consistently and required much less time. ADS is an accessible and robust tool for AH that can provide consistent analysis across protocols and nerve states.

Method, Material, and Machine: A Review for the Surgeon Using Three-Dimensional Printing for Accelerated Device Production.

BACKGROUND: Physicians are at the forefront of identifying innovative targets to address current medical needs. 3D printing technology has emerged as a state-of-the-art method of prototyping medical devices or producing patient-specific models that is more cost-efficient, with faster turnaround time, in comparison to traditional prototype manufacturing. However, initiating 3D printing projects can be daunting due to the engineering learning curve, including the number of methodologies, variables, and techniques for printing from which to choose. To help address these challenges, we sought to create a guide for physicians interested in venturing into 3D printing. STUDY DESIGN: All commercially available, plug-and-play, material and stereolithography printers costing less than $15,000 were identified via web search. Companies were contacted to obtain quotes and information sheets for all printer models. The qualifying printers' manufacturer specification sheets were reviewed, and pertinent variables were extracted. RESULTS: We reviewed 309 commercially available printers and materials and identified 118 printers appropriate for clinicians desiring plug-and-play models for accelerated device production. We synthesized this information into a decision-making tool to choose the appropriate parameters based on project goals. CONCLUSIONS: There is a growing clinical need for medical devices to reduce costs of care and increase access to personalized treatments; however, the learning curve may be daunting for surgeons. In this review paper, we introduce the "3Ms of 3D printing" for medical professionals and provide tools and data sheets for selection of commercially available, affordable, plug-and-play 3D printers appropriate for surgeons interested in innovation.

A preliminary prospective study of health-related quality of life among Chinese-American breast cancer survivors.

PURPOSE: This study examined the predictors of health-related quality of life (HRQOL) and changes in HRQOL over a 1-year period among Chinese-American breast cancer survivors (BCS). METHODS: A two-wave longitudinal research design included participants from hospital-based cancer registries and community organizations in Los Angeles. Participants completed mailed questionnaires at baseline and 12-month follow-up. HRQOL was measured using the Functional Assessment of Cancer Therapy-General (FACT-G v.4). Change in HRQOL was assessed using a 7-point meaningful change score. RESULTS: Participants were 73 Chinese-American BCS, a majority of whom were middle-aged (M = 54.6, SD = 9.2), lower income (63% < 45K), and diagnosed with stage I-II (83%) breast cancer. Regression analyses showed that multilevel contextual factors including general health perception, quality of care, life stress, and improvement in general health perception significantly predicted HRQOL at baseline and follow-up. The final model explained 72% of the variance of HRQOL. The examination of meaningful change indicated that improvement was reported by 32% (n = 22) and deterioration by 25% (n = 17); the majority indicated minimal change (43%, n = 30). Improvement was associated with increases in family communication, social support, and general health perception, while deterioration was associated with declines in social support, family communication, and general health perception. CONCLUSION: Findings indicate that among Chinese-American BCS, HRQOL is influenced by socioecological factors such as family communication and life stress. Results suggest that cancer survivorship outcomes research may benefit from theoretical foundations that examine the broader contextual dimensions that seem to impact and predict HRQOL. Implications for research are discussed.

Defining the relative impact of muscle versus Schwann cell denervation on functional recovery after delayed nerve repair.

Functional recovery following peripheral nerve injury worsens with increasing durations of delay prior to repair. From the time of injury until re-innervation occurs, denervated muscle undergoes progressive atrophy that limits the extent to which motor function can be restored. Similarly, Schwann cells (SC) in the distal nerve lacking axonal interaction progressively lose their capacity to proliferate and support regenerating axons. The relative contributions of these processes to diminished functional recovery is unclear. We developed a novel rat model to isolate the effects of SC vs. muscle denervation on functional recovery. Four different groups underwent the following interventions for 12 weeks prior to nerve transfer: 1) muscle denervation; 2) SC denervation; 3) muscle + SC denervation (negative control); 4) no denervation (positive control). Functional recovery was measured weekly using the stimulated grip strength testing (SGST). Animals were sacrificed 13 weeks post nerve transfer. Retrograde labeling was used to assess the number of motor neurons that regenerated their axons. Immunofluorescence was performed to evaluate target muscle re-innervation and atrophy, and to assess the phenotype of the SC within the distal nerve segment. Functional recovery in the muscle denervation and SC denervation groups mirrored that of the negative and positive control groups, respectively. The SC denervation group achieved better functional recovery, with a greater number of reinnervated motor endplates and less muscle atrophy, than the muscle denervation group. Retrograde labeling suggested a higher number of neurons contributing to muscle reinnervation in the muscle denervation group as compared to SC denervation (p > 0.05). The distal nerve segment in the muscle denervation group had a greater proportion of SCs expressing the proliferation marker Ki67 as compared to the SC denervation group (p < 0.05). Conversely, the SC denervation group had a higher percentage of senescent SCs expressing p16 as compared to the muscle denervation group (p < 0.05). The deleterious effects of muscle denervation are more consequential than the effects of SC denervation on functional recovery. The effects of 12 weeks of SC denervation on functional outcome were negligible. Future studies are needed to determine whether longer periods of SC denervation negatively impact functional recovery.

Positron Emission Tomography-Magnetic Resonance Imaging Pharmacokinetics, In Vivo Biodistribution, and Whole-Body Elimination of Mn-PyC3A.

OBJECTIVES: Mn-PyC3A is an experimental manganese (Mn)-based extracellular fluid magnetic resonance imaging (MRI) contrast agent that is being evaluated as a direct replacement for clinical gadolinium (Gd)-based contrast agents. The goals of this study were to use simultaneous positron emission tomography (PET)-MRI to (1) compare the whole-body pharmacokinetics, biodistribution, and elimination of Mn-PyC3A with the liver-specific contrast agent mangafodipir (Mn-DPDP), (2) determine the pharmacokinetics and fractional excretion of Mn-PyC3A in a rat model of renal impairment, and (3) compare whole-body elimination of Mn-PyC3A to gadoterate (Gd-DOTA) in a rat model of renal impairment. METHODS: Mn-PyC3A and Mn-DPDP were radiolabeled with the positron emitting isotope Mn-52 via Mn2+ exchange with 52MnCl2. Dynamic simultaneous PET-MRI was used to measure whole-body pharmacokinetics and biodistribution of Mn-52 immediately and out to 7 days after an intravenous 0.2 mmol/kg dose of [52Mn]Mn-PyC3A to normal or to 5/6 nephrectomy rats or a 0.01 mmol/kg dose of [52Mn]Mn-DPDP to normal rats. The fractional excretion and 1- and 7-day biodistribution in rats after the injection of 2.0 mmol/kg [52Mn]Mn-PyC3A (n = 11 per time point) or 2.0 mmol/kg Gd-DOTA (n = 8 per time point) were quantified by gamma counting or Gd elemental analysis, respectively. Comparisons of Mn-PyC3A pharmacokinetics and in vivo biodistribution in normal and 5/6 nephrectomy rats and comparisons of ex vivo Mn versus Gd biodistribution data in 5/6 nephrectomy were made with an unpaired t test. RESULTS: Dynamic PET-MRI data demonstrate that both [52Mn]Mn-PyC3A and [52Mn]Mn-DPDP were eliminated by mixed renal and hepatobiliary elimination but that a greater fraction of [52Mn]Mn-PyC3A was eliminated by renal filtration. Whole-body PET images show that Mn-52 from [52Mn]Mn-PyC3A was efficiently eliminated from the body, whereas Mn-52 from [52Mn]Mn-DPDP was retained throughout the body. The blood elimination half-life of [52Mn]Mn-PyC3A in normal and 5/6 nephrectomy rats was 13 ± 3.5 minutes and 23 ± 12 minutes, respectively (P = 0.083). Area under the curve between 0 and 60 minutes postinjection (AUC0-60) in the bladder of normal and 5/6 nephrectomy rats was 2600 ± 1700 %ID/cc*min and 750 ± 180 %ID/cc*min, respectively (P = 0.024), whereas AUC0-60 in the liver of normal and 5/6 nephrectomy rats was 33 ± 13 %ID/cc*min and 71 ± 16 %ID/cc*min, respectively (P = 0.011), indicating increased hepatobiliary elimination in 5/6 nephrectomy rats. The %IDs of Mn from [52Mn]Mn-PyC3A and Gd from Gd-DOTA recovered from 5/6 nephrectomy rats 1 day after injection were 2.0 ± 1.1 and 1.3 ± 0.34, respectively (P = 0.10) and 7 days after injection were 0.14 ± 0.11 and 0.41 ± 0.24, respectively (P = 0.0041). CONCLUSIONS: Mn-PyC3A has different pharmacokinetics and is more efficiently eliminated than Mn-DPDP in normal rats. Mn-PyC3A is efficiently eliminated from both normal and 5/6 nephrectomy rats, with increased fractional hepatobiliary excretion from 5/6 nephrectomy rats. Mn-PyC3A is more completely eliminated than Gd-DOTA from 5/6 nephrectomy rats after 7 days.

The Effect of Padded Adhesive Dressing and Static Body Position on Sacral Interface Pressure.

OBJECTIVES: Padded adhesive bandages are frequently used in the inpatient setting for sacral pressure injury prevention, but it is unclear whether they truly decrease interface pressure. We hypothesized such devices reduce sacral peak interface pressure in the supine position, which would be further reduced in 30-degree reclined and upright seated positions. METHODS: Study participants rested with their sacrum on a pressure-sensing mat, in 3 positions, for 30 seconds each: (1) sitting upright; (2) supine; and (3) supine against 30-degree wedge. Measurements were made with and without a padded adhesive bandage overlying the sacrum. Age, sex, and body mass index (BMI) were collected. These variables were entered sequentially, in an a priori order to construct a linear mixed-effects model. RESULTS: Forty healthy adults participated. After controlling for by-subject variation, age, and sex, BMI did not influence peak sacral pressure (P = 0.22), although the effect of body position was significant (P < 0.01). Subsequent addition of padded adhesive dressing was nonsignificant (P = 0.17); sacral peak pressure was similar with a padded adhesive dressing (247.8 ± 147.3 mm Hg) or without (mean ± standard deviation = 229.8 ± 127.7 mm Hg). Lastly, there was no significant interaction between BMI and body position (P = 0.11). CONCLUSIONS: Padded adhesive bandages did not reduce interface pressure in any position. Sacral pressure was highest in the supine position and was not specifically affected by BMI. If padded bandages provide clinically significant reduction in pressure injury incidence, it is not simply through the reduction of interface pressure.

Rational Ligand Design Enables pH Control over Aqueous Iron Magnetostructural Dynamics and Relaxometric Properties.

Complexes of Fe3+ engage in rich aqueous solution speciation chemistry in which discrete molecules can react with solvent water to form multinuclear µ-oxo and µ-hydroxide bridged species. Here we demonstrate how pH- and concentration-dependent equilibration between monomeric and µ-oxo-bridged dimeric Fe3+ complexes can be controlled through judicious ligand design. We purposed this chemistry to develop a first-in-class Fe3+-based MR imaging probe, Fe-PyCy2AI, that undergoes relaxivity change via pH-mediated control of monomer vs dimer speciation. The monomeric complex exists in a S = 5/2 configuration capable of inducing efficient T1-relaxation, whereas the antiferromagnetically coupled dimeric complex is a much weaker relaxation agent. The mechanisms underpinning the pH dependence on relaxivity were interrogated by using a combination of pH potentiometry, 1H and 17O relaxometry, electronic absorption spectroscopy, bulk magnetic susceptibility, electron paramagnetic resonance spectroscopy, and X-ray crystallography measurements. Taken together, the data demonstrate that PyCy2AI forms a ternary complex with high-spin Fe3+ and a rapidly exchanging water coligand, [Fe(PyCy2AI)(H2O)]+ (ML), which can deprotonate to form the high-spin complex [Fe(PyCy2AI)(OH)] (ML(OH)). Under titration conditions of 7 mM Fe complex, water coligand deprotonation occurs with an apparent pKa 6.46. Complex ML(OH) dimerizes to form the antiferromagnetically coupled dimeric complex [(Fe(PyCy2AI))2O] ((ML)2O) with an association constant (Ka) of 5.3 ± 2.2 mM-1. The relaxivity of the monomeric complexes are between 7- and 18-fold greater than the antiferromagnetically coupled dimer at applied field strengths ranging between 1.4 and 11.7 T. ML(OH) and (ML)2O interconvert rapidly within the pH 6.0-7.4 range that is relevant to human pathophysiology, resulting in substantial observed relaxivity change. Controlling Fe3+ µ-oxo bridging interactions through rational ligand design and in response to local chemical environment offers a robust mechanism for biochemically responsive MR signal modulation.

An all-photonic focal-plane wavefront sensor.

Adaptive optics (AO) is critical in astronomy, optical communications and remote sensing to deal with the rapid blurring caused by the Earth's turbulent atmosphere. But current AO systems are limited by their wavefront sensors, which need to be in an optical plane non-common to the science image and are insensitive to certain wavefront-error modes. Here we present a wavefront sensor based on a photonic lantern fibre-mode-converter and deep learning, which can be placed at the same focal plane as the science image, and is optimal for single-mode fibre injection. By measuring the intensities of an array of single-mode outputs, both phase and amplitude information on the incident wavefront can be reconstructed. We demonstrate the concept with simulations and an experimental realisation wherein Zernike wavefront errors are recovered from focal-plane measurements to a precision of 5.1 × 10-3 π radians root-mean-squared-error.

Reduced Bacterial Burden of the Skin Surrounding the Shoulder Joint Following Topical Protocatechuic Acid Application: Results of a Pilot Study.

BACKGROUND: Reducing the rising health-care burden associated with shoulder surgical site infection (SSI) is of paramount importance. The purpose of this study was to investigate the antimicrobial efficacy of protocatechuic acid (PCA) as a topical reagent for surgical skin antisepsis surrounding the shoulder joint. METHODS: This was a 2-phase skin-disinfection trial involving the human shoulder. The shoulders of healthy volunteers were randomized to topical treatment with PCA (a 10% concentration of PCA in Phase I [11 subjects] and a 17% concentration in Phase II [12 subjects]), with a control of isopropyl alcohol (IPA) applied to the contralateral shoulder. Mechanical scraping was performed for skin harvest following reagent application, and samples were sent for aerobic and anaerobic culture. Sterilization rates and bacterial counts were determined for each treatment group, and the proportion of subjects with persistent Cutibacterium acnes colonization following topical application of PCA was determined using DNA sequencing analysis. RESULTS: The topical application of 10% PCA was associated with significantly higher aerobic and anaerobic sterilization rates (90.9% and 81.8%, respectively) compared with treatment with IPA (p = 0.0143 and p = 0.0253, respectively). The topical application of 17% PCA was associated with a significantly higher anaerobic sterilization rate (83.3%) and trended toward a significantly higher aerobic sterilization rate (91.7%) compared with treatment with IPA (p = 0.0143 and p = 0.083, respectively). C. acnes was identified in 18.2% and 0% of subjects following treatment with 10% and 17% PCA, respectively. CONCLUSIONS: The topical application of PCA was associated with a reduction in the bacterial burden of human shoulder skin and demonstrated dose-dependent antimicrobial activity against C. acnes in young, healthy subjects. Clinical studies in a shoulder surgical population are warranted to determine the potential for application in surgical skin antisepsis to reduce shoulder SSI. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Protocatechuic Acid as a Topical Antimicrobial for Surgical Skin Antisepsis: Preclinical Investigations.

BACKGROUND: There is a need for novel skin antiseptic agents to combat the health-care burdens associated with surgical site infection (SSI) and bacterial resistance. The purpose of this proof-of-principle pilot study was to investigate the potential of the phenolic compound protocatechuic acid (PCA) as a topical antimicrobial for surgical skin antisepsis. METHODS: The Kirby-Bauer method of disc diffusion was used to investigate the in vitro antimicrobial activity and comparative effectiveness of PCA and 7 related compounds against SSI pathogens. To explore the in vivo efficacy of topical PCA for providing deep, penetrating skin antisepsis, living Cutibacterium acnes was intradermally injected into the skin of female BALB/c mice. Mice were assigned to treatment with daily applications of topical PCA at 3 doses (78, 39, and 19.5 mM) or no treatment (n = 2 mice per group). After 96 hours, infected skin samples were harvested to compare mean C. acnes counts by treatment. RESULTS: Compared with other polyphenols, PCA demonstrated the broadest spectrum of antimicrobial activity against tested SSI pathogens, including drug-resistant organisms. At 96 hours following infection, the mean C. acnes burden in untreated mice was 6.65 log colony-forming units (CFUs) per gram of skin. Compared with the untreated group, daily topical application of 78 mM of PCA was associated with a significantly lower C. acnes CFU burden in mice skin (mean, 5.51 log CFUs per gram of skin; p = 0.0295). Both lower dosages of topical PCA failed to show an effect. CONCLUSIONS: PCA demonstrated laboratory efficacy against pathogens implicated in SSI, including drug-resistant organisms. In vivo, topical PCA demonstrated dose-dependent skin penetration and antimicrobial activity against mouse skin C. acnes loads. Human clinical studies exploring the antimicrobial efficacy of topical PCA for preoperative shoulder skin antisepsis are warranted. CLINICAL RELEVANCE: Topical PCA may have the potential to improve current shoulder SSI treatment and prevention protocols.

Vascularized, Denervated Muscle Targets: A Novel Approach to Treat and Prevent Symptomatic Neuromas.

There are many surgical approaches described to treat and prevent symptomatic neuromas, each of which has significant limitations. Here we describe the rationale and technical approach for a novel method that carries the promise of addressing some of these limitations.

Recent Developments Are Changing Extensor Tendon Management.

LEARNING OBJECTIVES: After reviewing this article, the participant should be able to: Start early protected movement at 3 to 5 days after surgery with relative motion extension splinting for zone 5 extensor tendon lacerations over the hand. Allow patients to resume regular activities much sooner than the conventional 3 to 4 weeks of splinting after extensor tendon repair. Improve the rehabilitation of boutonniere deformities with relative motion splinting. SUMMARY: This article focuses on surgery and rehabilitation of extensor tendon injuries from the proximal interphalangeal joint (boutonniere) to the wrist. Relative motion flexion and extension splinting and wide awake, local anesthesia, no tourniquet surgery have revolutionized the management of these lesions, with early protected movement, sooner return to regular activities, and improved rehabilitation. This article explains and illustrates these new advances in extensor tendon management.