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Undistorted monolayer graphene has energy bands which cross at protected Dirac points. It elastically deforms and much research has assumed the Dirac description persists, now in a curved space and coupled to a gauge field related to lattice strain. We show this is incorrect by using a real space gradient expansion to study how the Dirac equation derives from the tight binding model. Generic spatially varying hopping functions give rise to large magnetic fields which spoil the truncation in derivatives. In the perturbative regime, the only consistent truncation to Dirac is one with nontrivial gauge field but in flat space. One can instead fine tune the magnetic field to be small, and we derive the resulting differential condition that the hopping functions must satisfy to yield a consistent truncation to Dirac in curved space. We consider whether mechanical effects might impose this fine tuning, but find this is not the case for a simple elastic membrane model., v1. 5 pages; v2. journal version of article, text improvements and some discussion expanded, some references added, title changed to adhere to journal policy, 7 pages

We construct new families of deformed supersymmetric field theories which break space-time symmetries but preserve half of the original supersymmetry. We do this by writing deformations as couplings to background multiplets. In many cases it is important to use the off-shell representation as auxiliary fields of the non-dynamical fields must be turned on to preserve supersymmetry. We also consider backgrounds which preserve some superconformal symmetry, finding scale-invariant field profiles, as well as $\mathcal{N} =2$ theories on $S^3$. We discuss how this is related to previous work on interface SCFTs and other holographic calculations., Comment: 5 pages

Background Correction of talonavicular uncoverage (TNU) in adult-acquired flatfoot deformities (AAFD) can be a challenge. Lateral column lengthening (LCL) traditionally is utilized to address this. The primary study objective is examining stage II AAFD patients and determining if correction can be achieved with subtalar fusion (STF) comparable to LCL. Methods Following institutional review board approval, retrospective chart review performed identifying patients meeting criteria for stage IIB AAFD who underwent either STF with concomitant flatfoot procedures (but not LCL) to correct TNU, or who underwent LCL as part of their flatfoot reconstruction. Patients indicated for STF had one or more of the following: higher body mass index (BMI), were older, had greater deformity, lateral impingement pain, intraoperative spring ligament hyperlaxity. Patients without 1-year follow-up or compete records were excluded. All other patients were included. A total of 27 isolated STFs identified, along with 143 who underwent LCL. Pre-/postoperative radiographic parameters obtained as well as PROMIS (Patient-Reported Outcomes Measurement Information System) and FAOS (Foot and Ankle Outcome Score) scores. Radiographic and patient reported outcomes both preoperatively and at 1-year follow-up evaluated for both groups. Results STF patients were older ( P < .05), with higher BMIs ( P < .004). STF had significantly worse TNU ( P < .001) than LCL patients, and average change in STF TNU was larger than LCL change postoperatively ( P = .006), after adjusting for age, BMI, gender. PROMIS STF improvement reached statistical significance in Physical Function (P 0.011), for FAOS Pain (P 0.025) and Function ( P = 0.04). Conclusions STF can be used in appropriately indicated patients to correct flatfoot deformity without compromising radiographic or clinical, correcting not only hindfoot valgus, but also talonavicular uncoverage (TNU) and corresponding medial arch collapse. Levels of Evidence: Level III: Retrospective chart review comparison study (case control)

We construct a continuous one parameter family of $AdS_4\times S^1\times S^5$ S-fold solutions of type IIB string theory which have nontrivial $SL(2,\mathbb{Z})$ monodromy in the $S^1$ direction. The solutions span a subset of a conformal manifold that contains the known $\mathcal{N}=4$ S-fold SCFT in $d=3$, and generically preserve $\mathcal{N}=2$ supersymmetry. We also construct RG flows across dimensions, from $AdS_5\times S^5$, dual to $\mathcal{N}=4$, $d=4$ SYM compactified with a twisted spatial circle, to various $AdS_4\times S^1\times S^5$ S-fold solutions, dual to $d=3$ SCFTs. We construct additional flows between the $AdS_5$ dual of the Leigh-Strassler SCFT and an $\mathcal{N}=2$ S-fold as well as RG flows between various S-folds., Comment: 49 pages, 8 figures. Typos in table 4 corrected. Published version

Background: Arthrodesis of the first metatarsophalangeal (MTP) joint has been shown to be effective in alleviating pain and correcting deformity in hallux rigidus. However, outcomes in specific sports and physical activities remain unclear. The aim of this study was to assess sports and physical activities in young patients following first MTP joint arthrodesis and to compare these results with clinical outcomes. Methods: Patients between ages 18 and 55 years who underwent MTP arthrodesis were identified by review of a prospective registry. Fifty of 73 eligible patients (68%) were reached for follow-up at a mean of 5.1 (range, 2.2-10.2) years with a mean age at surgery of 49.7 (range, 23-55) years. Physical activity was evaluated with a previously developed sports-specific, patient-administered questionnaire. Clinical outcomes were evaluated with the Foot and Ankle Outcome Score (FAOS). Results: Patients participated in 22 different sports and physical activities. The most common were walking, biking, weightlifting, swimming, running, and golf. Compared to preoperatively, patients rated 27.4% of activities as less difficult, 51.2% as the same, and 21.4% as more difficult. Patients returned to 44.6% of preoperative physical activities in less than 6 months and reached their maximal level of participation in 88.6% of physical activities. Ninety-six percent of patients (48/50) were satisfied with the procedure regarding return to sports and physical activities. Improvements in the FAOS Symptoms subscore were associated with increased postoperative running and walking duration, and improvements in FAOS Pain subscores were associated with greater patient satisfaction. Conclusion: Patients were able to participate in a wide variety of sports and physical activities postoperatively. Some patients reported increased difficulty, but were nonetheless satisfied with the procedure regarding physical activity participation. These findings suggest that first MTP joint arthrodesis is a reasonable option in young, active patients, and may be used to guide postoperative expectations. Level of Evidence: Level IV, retrospective case series.

We construct infinite new classes of $AdS_4\times S^1\times S^5$ solutions of type IIB string theory which have non-trivial $SL(2,\mathbb{Z})$ monodromy along the $S^1$ direction. The solutions are supersymmetric and holographically dual, generically, to $\mathcal{N}=1$ SCFTs in $d=3$. The solutions are first constructed as $AdS_4\times \mathbb{R}$ solutions in $D=5$ $SO(6)$ gauged supergravity and then uplifted to $D=10$. Unlike the known $AdS_4\times \mathbb{R}$ S-fold solutions, there is no continuous symmetry associated with the $\mathbb{R}$ direction. The solutions all arise as limiting cases of Janus solutions of $d=4$, $\mathcal{N}=4$ SYM theory which are supported both by a different value of the coupling constant on either side of the interface, as well as by fermion and boson mass deformations. As special cases, the construction recovers three known S-fold constructions, preserving $\mathcal{N}=1,2$ and 4 supersymmetry, as well as a recently constructed $\mathcal{N}=1$ $AdS_4\times S^1\times S^5$ solution (not S-folded). We also present some novel "one-sided Janus" solutions that are non-singular., 56 pages, 13 figures; very minor changes, published version

Missed fractures are the most common diagnostic error in emergency departments and can lead to treatment delays and long-term disability. Here we show through a multi-site study that a deep-learning system can accurately identify fractures throughout the adult musculoskeletal system. This approach may have the potential to reduce future diagnostic errors in radiograph interpretation.

Category: Other Introduction/Purpose: Cases of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus (COVID-19) first emerged in Wuhan, China, in December 2019. Since then, the virus has spread globally at a rapid pace. The first case in New York City was reported on March 1, 2020, and the World Health Organization (WHO) declared a pandemic on March 11, 2020. New York City rapidly became the epicenter of the pandemic, with hospitals across the city making a number of changes to accommodate the influx of COVID-19 patients. Here, we describe our experience in adapting to the COVID-19 pandemic as a department consisting of 10 foot and ankle fellowship-trained surgeons with up to 28 years of individual experience in an academic orthopedic hospital. Methods: Information was obtained from direct interviews with surgeons in the Foot and Ankle Service and from our institution’s intranet. Additional information was obtained by viewing twice-weekly livestreams from March 27th, 2020 to May 1st, 2020 held by the Surgeon-In-Chief, which detailed hospital-wide policies and initiatives being implemented in the wake of the COVID-19 pandemic. Results: On March 17, 2020, all elective surgeries were suspended at our institution, and a list of essential procedures was established. In-person clinical visits were limited to new patients being evaluated for essential procedures and first postoperative visits for returning patients, with all patients receiving pre-visit and on-site screening for COVID-19. All other new patient and follow-up appointments were conducted via telehealth visits. Much of our main hospital was repurposed to accept transfers of both COVID-negative and COVID-positive patients. A postanesthesia care unit and a floor of 9 operating rooms were repurposed as negative-pressure rooms for the care of critical COVID-positive patients on ventilators. An Orthopedic Triage Center (OTC) was established to relieve the patient load in the emergency departments of other hospitals in the city. Conclusion: By changing the way we delivered foot and ankle care and repurposing the roles of our employees and our institution, we have adapted strategies to continue delivering care to our patients. As we transition toward a ‘new normal,’ our goals are to gradually progress toward normal operations while keeping our patients and employees safe. With these gradual steps, we hope to emerge from this pandemic stronger and ready to adapt to the ever-changing needs of our community.

We construct gravitational solutions that holographically describe two different $d=4$ SCFTs joined together at a co-dimension one, planar RG interface and preserving $d=3$ superconformal symmetry. The RG interface joins $\mathcal{N}=4$ SYM theory on one side with the $\mathcal{N}=1$ Leigh-Strassler SCFT on the other. We construct a family of such solutions, which in general are associated with spatially dependent mass deformations on the $\mathcal{N}=4$ SYM side, but there is a particular solution for which these deformations vanish. We also construct a Janus solution with the Leigh-Strassler SCFT on either side of the interface. Gravitational solutions associated with superconformal interfaces involving ABJM theory and two $d=3$ $\mathcal{N}=1$ SCFTs with $G_2$ symmetry are also discussed and shown to have similar properties, but they also exhibit some new features., 33 pages, 12 pages; references added, typos fixed. Published version

BACKGROUND Neuraxial anesthesia is often viewed as superior to general anesthesia but may delay discharge. Comparisons do not typically use multimodal analgesics and nerve blockade. Combining nerve blockade with general anesthesia may reduce pain, opioid consumption, and nausea. We hypothesized that general anesthesia (with nerve blocks) would lead to earlier readiness for discharge, compared to spinal anesthesia (with nerve blocks). METHODS All patients underwent ambulatory foot and ankle surgery, with a predicted case duration of 1-3 hours. All patients received popliteal and adductor canal nerve blocks using bupivacaine and dexamethasone. No intraoperative opioids were administered. All patients received ondansetron, dexamethasone, ketamine, and ketorolac. Patients, data collectors, and the data analyst were not informed of group assignment. Patients were randomized to spinal or general anesthesia with concealed allocation. Spinal anesthesia was performed with mepivacaine and accompanied with propofol sedation. After general anesthesia was induced with propofol, a laryngeal mask airway was inserted, followed by sevoflurane and propofol. Time until ready for discharge, the primary outcome, was compared between groups after adjusting for age and surgery time using multivariable unconditional quantile regression. Secondary outcomes compared at multiple timepoints were adjusted for multiple comparisons using the Holm-Bonferroni step-down procedure. RESULTS General anesthesia patients were ready for discharge at a median of 39 minutes earlier (95% confidence interval, 2-75; P = .038) versus spinal anesthesia patients. Patients in both groups met readiness criteria for discharge substantially before actual discharge. Pain scores at rest were higher among general anesthesia patients 1 hour after leaving the operating room (adjusted difference in means, 2.1 [95% confidence interval, 1.0-3.2]; P < .001). Other secondary outcomes (including opioid use, opioid side effects, nausea, headache, sore throat, and back pain) were not different. CONCLUSIONS General anesthesia was associated with earlier readiness for discharge, but the difference may not be clinically significant and did not lead to earlier actual discharge. Most secondary outcomes were not different between groups. The choice of spinal or general anesthesia as an adjunct to peripheral nerve blockade can reflect patient, clinician, and institutional preferences.

Category: Midfoot/Forefoot Introduction/Purpose: Hallux rigidus is a common arthritic condition seen by foot and ankle specialists. Historically, surgical treatment options have varied from an isolated cheilectomy to first metatarsophalangeal joint fusion. More recently, first metatarsophalangeal (MTP) joint hemiarthroplasty with a polyvinyl alcohol (PVA) hydrogel implant (Cartiva) has become a popular surgical option. A randomized clinical trial sponsored by the manufacturers of the implant showed equivalent pain relief and functional outcome scores at 2 year follow-up when compared to patients undergoing first MTP fusion. In addition, the study reported no bone loss, implant wear or loosening. We retrospectively reviewed 1 year PROMIS score outcomes, clinical outcomes and implant survivorship of patients treated with first MTP hemiarthroplasty with the Cartiva implant at an academic, multi-surgeon center. Methods: We retrospectively reviewed 54 consecutive patients that underwent first MTP hemiarthroplasty with Cartiva for hallux rigidus between January 1, 2017 and December 1, 2017. Minimum follow-up criteria was 1 year, with the average being 1.37 years and maximum follow-up of 1.9 years. The Coughlin radiographic grading of disease severity averaged 2.18 at the time of implantation on a scale of 0 to 4. Surgery was performed by 8 fellowship-trained orthopedic foot and ankle surgeons at an academic institution. Baseline PROMIS scores (physical function, pain interference, global function, global mental, depression) and PROMIS scores acquired at 1 year postoperative were compared and evaluated using the Wilcoxon signed t-test. Clinical outcomes and postoperative complications/events were documented through review of electronic medical records. At the time of the study, 49 patients had reached 1 year follow-up with an average age of 56 (range, 33 - 74) years at the time of implantation. Results: Physical function, pain interference, global function and depression scores all demonstrated clinically and statistically significant improvement at 1 year postoperative. Global mental score did not show significant improvement at the one year follow-up. One patient underwent revision surgery to a 1st MTP fusion for persistent pain. Three patients had postoperative soft tissue swelling requiring prolonged retained sutures. Five patients underwent therapeutic injection with steroid between 2 - 11 months postoperative for persistent discomfort which improved. Five patients were prescribed orthotics between 3 - 6 months follow-up. One patient sustained a metatarsal fracture during the application of the implant requiring ORIF but retained the implant. Implant retention at 1 year was 98% (48/49). No correlation between preoperative radiographic grading and the incidence of poor clinical outcomes. Conclusion: To our knowledge, this is the first study that demonstrates the outcomes of synthetic cartilage implants using a large series of surgeons without affiliation or consultation for the implant company. One year following first MTP hemiarthroplasty with PVA hydrogel implant (Cartiva), functional and pain scores improved significantly, but did not show significant improvement with global mental scores. The implant displayed excellent survivorship at the 1 year time point, with only one patient undergoing surgical revision. Treatment of hallux rigidus with the PVA hydrogel implant - Cartiva, shows improved patient outcomes and has reassuring results at one year.

We construct supersymmetric solutions of $D=11$ supergravity, preserving 1/4 of the supersymmetry, that are holographically dual to ABJM theory which has been deformed by spatially varying mass terms depending on one of the two spatial directions. We show that the BPS equations reduce to the Helmholtz equation on the complex plane leading to rich classes of new solutions. In particular, the construction gives rise to infinite classes of supersymmetric boomerang RG flows, as well as generalising a known Janus solution., Comment: 34 pages, 6 figures. Minor changes including a new analytic result on the refractive index. Version to be published

We consider real mass and FI deformations of ABJM theory preserving supersymmetry in the large N limit, and compare with holographic results. On the field theory side, the problems amounts to a spectral problem of a non-Hermitian Hamiltonian. For certain values of the deformation parameters this is invariant under an antiunitary operator (generalised $$ \mathcal{P}\mathcal{T} $$ P T symmetry), which ensures the partition function remains real and allows us to calculate the free energy using tools from statistical physics. The results obtained are compatible with previous work, the important new feature being that these are obtained directly from the real deformations, without analytic continuation.

Background: First metatarsophalangeal (MTP) joint arthrodesis is a common procedure for treatment of arthritis of the first MTP joint. The primary aim of this study was to evaluate the functional outcomes of a series of patients of multiple surgeons undergoing first MTP joint arthrodesis, emphasizing the functional gains with respect to daily activity that can be expected after this procedure. Methods: A retrospective review of 53 patients who underwent successful isolated first MTP joint arthrodesis with either a plate and screw or independent screw construct was performed at our institution over a 6-year period. Successful fusion was defined as no lucency at the first MTP joint and bridging of 2 or more cortices on the anteroposterior, lateral, and oblique radiographic views at final follow-up. Demographic information and radiographs were evaluated for all patients. Preoperative and postoperative Foot and Ankle Outcome Score (FAOS) and Short Form Health Status Survey (SF) 36/12 functional outcome scores, as well as responses from an activity- and footwear-specific questionnaire, were evaluated and compared between the 2 fixation methods. Fifty-three patients (56 feet) had radiographs showing successful fusions after being treated for advanced degenerative arthritis of the first MTP joint with arthrodesis. Average time to union was 5.4 months. Results: There was a significant reduction in difficulty in performing daily activities, with all subscales of the FAOS and the SF-12v2 significantly improving postoperatively ( P < .05). The majority of patients stated that their foot looked and felt better and were satisfied with the procedure. Five patients experienced painful hardware, which required removal. Conclusion: First MTP joint arthrodesis was successful in improving patient-reported outcomes, particularly the ability to perform daily activities. Most patients had little to no functional limitation and were satisfied with their outcome. The greatest functional improvements were seen in patients’ ability to walk distances and perform low-impact sport activity. Level of Evidence: Level III, retrospective comparative study.

The modified Lapidus procedure is widely used to correct hallux valgus but has been reported with high nonunion rates. In this study, we retrospectively reviewed the nonunion rate of the modified Lapidus procedure performed with rigid cross screw fixation, meticulous joint preparation, and shear-strain-relieved calcaneal bone graft.Does the performance of the Lapidus procedure with rigid cross screw fixation, complete joint preparation, and shear-strain-relieved calcaneal bone graft achieve higher union rates than currently reported? If nonunion does occur, what is the clinical course?We reviewed both radiographic and clinical results of the modified Lapidus procedure with the above technique in 171 patients (182 feet). Evaluation included age, gender, tobacco use, diabetic status, and radiographic analysis at least 3 months postoperatively.The modified Lapidus procedure described above resulted in a union rate of 97.3% (177 of 182 feet). Three of the five feet with radiographic nonunions were clinically symptomatic.The union rate of the modified Lapidus procedure is higher than previously reported when performed with rigid cross screw fixation, meticulous joint preparation, and shear-strain-relieved bone graft. Nonunion of the first tarsometatarsal joint should be considered an infrequent occurrence.

Background and Objectives Sciatic nerve block provides analgesia after foot and ankle surgery, but block duration may be insufficient. We hypothesized that perineural dexamethasone and buprenorphine would reduce pain scores at 24 hours. Methods Ninety patients received ultrasound-guided sciatic (25 mL 0.25% bupivacaine) and adductor canal (10 mL 0.25% bupivacaine) blockade, with random assignment into 3 groups (30 patients per group): control blocks + intravenous (IV) dexamethasone (4 mg) (control); control blocks + IV buprenorphine (150 μg) + IV dexamethasone (IV buprenorphine); and nerve blocks containing buprenorphine + dexamethasone (perineural). Patients received mepivacaine neuraxial anesthesia and postoperative oxycodone/acetaminophen, meloxicam, pregabalin, and ondansetron. Patients and assessors were blinded to group assignment. The primary outcome was pain with movement at 24 hours. Results There was no difference in pain with movement at 24 hours (median score, 0). However, the perineural group had longer block duration versus control (45.6 vs 30.0 hours). Perineural patients had lower scores for “worst pain” versus control (median, 0 vs 2). Both IV buprenorphine and perineural groups were less likely to use opioids on the day after surgery versus control (28.6%, 28.6%, and 60.7%, respectively). Nausea after IV buprenorphine (but not perineural buprenorphine) was severe, frequent, and bothersome. Conclusions Pain scores were very low at 24 hours after surgery in the context of multimodal analgesia and were not improved by additives. However, perineural buprenorphine and dexamethasone prolonged block duration, reduced the worst pain experienced, and reduced opioid use. Intravenous buprenorphine caused troubling nausea and vomiting. Future research is needed to confirm and extend these observations.

Background:The number of opioids prescribed and used has increased precipitously over the past 2 decades for a number of reasons and has led to increases in long-term dependency, opioid-related deaths, and diversion. Most studies examining the role of prescribing habits have investigated nonoperative providers, although there is some literature describing perioperative opioid prescription and use. There are no studies looking at the number of pills consumed after outpatient foot and ankle surgeries, nor are there guidelines for how many pills providers should prescribe. The purpose of this study was to quantify the number of narcotic pills taken by opioid-naïve patients undergoing outpatient foot and ankle surgeries with regional anesthesia.Methods:Eighty-four patients underwent outpatient foot and ankle surgeries under spinal blockade and long-acting popliteal blocks. Patients were given 40 or 60 narcotic pills, a 3-day supply of ibuprofen, deep vein thrombosis prophylaxis, and antiemetics. Patients received surveys at postoperative day (POD) 3, 7, 14, and 56 documenting if they were still taking narcotics, the quantity of pills consumed, whether refills were obtained, their pain level, and their reason for stopping opioids.Results:Patients consumed a mean of 22.5 pills, with a 95% confidence interval from 18 to 27 pills. Numerical Rating Scale pain scores started at 4 on POD 3 and decreased to 1.8 by POD 56. The percentage of patients still taking narcotics decreased from 55% on POD 3 to 2.8% by POD 56. Five new prescriptions were given during the study, with 3 being due to side effects from the original medication.Conclusions:Patients receiving regional anesthesia for outpatient foot and ankle surgeries reported progressively lower pain scores with low narcotic use up to 56 days postoperatively. We suggest that providers consider prescribing 30 pills as the benchmark for this patient population.Level of Evidence:Level II, prospective comparative study.

Background:Autogenous bone grafting is commonly used as an adjuvant in foot and ankle procedures. The iliac crest and tibia are common sources of autogenous bone graft but require a separate operative site and have been reported to have significant morbidity including pain, fractures, and prolonged hospitalization. Bone grafting from the posterolateral calcaneus offers advantages such as a single operative field, ability to be done under an ankle block, and a theoretical low complication rate. We report our morbidity and complications of percutaneous calcaneal autograft bone harvest in patients undergoing foot operations.Methods:Between 2006 and 2010, 6 foot and ankle surgeons performed a calcaneal bone graft on 393 patients undergoing foot procedures. Outcomes were measured through the use of a 4-question survey evaluating pain, subjective sensitivity at the incision site, numbness at the incision site, and limitation of shoe wear at a minimum of 1 year following the operation. Patient records were also examined for any additional complications that may have been reported.Results:Of the 393 patients eligible for this study, 210 patients responded at an average of 2.8 years (range, 1.2-5.8 years) after the operation (minimum 1 year). Of those, 181 patients (86.2%) reported no problems. Minor complications included 6 patients (2.9%) who experienced only incisional nerve sensitivity, 4 patients (1.9%) with only incisional pain, 4 patients (1.9%) who reported some degree of incisional numbness only, 2 patients (1.0%) who reported only shoe wear limitations, and 10 patients (4.8%) who had a combination of symptoms. Three patients (1.4%) had more significant complications, which consisted of a pathological fracture through the graft site, a calcaneal stress fracture, and 1 patient with permanent numbness along the distribution of the sural nerve.Conclusion:Calcaneal bone graft was an easily accessible source of local autogenous bone graft for foot and ankle procedures. Despite the simplicity of the procedure, minor complications are not infrequent, with 13.8% of patients reporting some residual symptoms along the lateral border of the calcaneus when bone graft was obtained through an oblique incision.Level of Evidence:Level IV, case series.

Lateral column lengthening (LCL) is used to address the forefoot abduction associated with the adult acquired flatfoot. This opening wedge osteotomy can be filled with either allograft or autograft bone.The investigators sought to determine union rates and any loss of correction in patients undergoing LCL with autograft versus allograft.Over a 3-year period, 126 LCLs performed by five surgeons in 120 patients were reviewed. Autograft was used in 51 patients, allograft in 75 patients. Times to clinical and radiographic union were established for these patients. Any loss of correction of forefoot abduction as manifested by talonavicular uncoverage was recorded for those grafts that healed. Failure was defined as nonunion or loss of 50% or greater correction. The size of the implanted graft was assessed as a risk factor for failure.There were 20 total failures: seven in patients with autograft and 13 in patients with allograft (p = 0.63). The size of the implanted graft was larger in those patients that did fail (p = 0.04).The rate of nonunion and loss of correction for LCL was not significantly different between allograft and autograft. The overall rate of nonunion may be higher than has previously been reported.

Background: Many authors have reported on patient satisfaction from foot and ankle surgery, but rarely on expectations, which may vary widely between patients and strongly affect satisfaction. In this study, we aimed to develop a patient-derived survey on expectations from foot and ankle surgery. Methods: We developed and tested our survey using a 3-phase process. Patients with a wide spectrum of foot and ankle diagnoses were enrolled. In phase 1, patients were interviewed preoperatively with open-ended questions about their expectations from surgery. Major concepts were grouped into categories that were used to form a draft survey. In phase 2, the survey was administered to preoperative patients on 2 occasions to establish test-retest reliability. In phase 3, the final survey items were selected based on weighted kappa values for response concordance and clinical relevance. Results: In phase 1, 94 preoperative patients volunteered 655 expectations. Twenty-nine representative categories were discerned by qualitative analysis and became the draft survey. In phase 2, another 60 patients completed the draft survey twice preoperatively. In phase 3, 23 items were retained for the final survey. For retained items, the average weighted kappa value was 0.54. An overall score was calculated based on the amount of improvement expected for each item on the survey and ranged from zero to 100, with higher scores indicating more expectations. For patients in phase 2, mean scores for both administrations were 65 and 66 and approximated normal distributions. The intraclass correlation coefficient between scores was 0.78. Conclusion: We developed a patient-derived survey specific to foot and ankle surgery that is valid, reliable, applicable to diverse diagnoses, and includes physical and psychological expectations. The survey generates an overall score that is easy to calculate and interpret, and thus offers a practical and comprehensive way to record patients’ expectations. We believe this survey may be used preoperatively by surgeons to help guide patients’ expectations and facilitate shared decision making. Level of Evidence: Level II, cross-sectional study.

For theories of relativistic matter fields there exist two possible definitions of the stress-energy tensor, one defined by a variation of the action with the coframes at fixed connection, and the other at fixed torsion. These two stress-energy tensors do not necessarily coincide and it is the latter that corresponds to the Cauchy stress measured in the lab. In this note we discuss the corresponding issue for non-relativistic matter theories. We point out that while the physical non-relativistic stress, momentum, and mass currents are defined by a variation of the action at fixed torsion, the energy current does not admit such a description and is naturally defined at fixed connection. Any attempt to define an energy current at fixed torsion results in an ambiguity which cannot be resolved from the background spacetime data or conservation laws. We also provide computations of these quantities for some simple non-relativistic actions., 31 pages, one appendix. Minor clarifications added and typos fixed

Category: Other Introduction/Purpose: Functional outcomes scores routinely used in orthopedic research are limited in that they are developed solely from a surgeon’s perspective. Very few studies have investigated patients’ expectations from foot and ankle surgery. Many authors have reported on patient satisfaction, but rarely on expectations, which may vary widely between patients and even strongly affect satisfaction. In this cross-sectional study, we aimed to develop and test a patient-derived expectations survey for patients undergoing foot and ankle surgery. Methods: Using a three-phase process, we developed and tested a patient-derived expectations survey. Patients with a wide spectrum of foot and ankle diagnoses were enrolled, including the major diagnoses of ankle arthritis, ankle instability, ankle osteochondral lesions, flatfoot deformity, hallux valgus, and hallux rigidus. In phase 1, patients were interviewed preoperatively with open-ended questions about their expectations from surgery. Responses were independently assessed by three reviewers using qualitative techniques. Major concepts were grouped into categories which were used to form a draft survey. In phase 2, the survey was administered to preoperative patients on two occasions to establish test-retest reliability. In phase 3, the final survey items were selected based on weighted kappa values for response concordance and clinical relevance, and a scoring rubric was developed. Results: In phase 1, 94 preoperative patients with diverse foot or ankle pathology (mean age 50 ± 15 years, 63% women) volunteered 655 expectations. 29 representative categories were discerned by qualitative analysis and became the draft survey. In phase 2, another 60 patients (mean age 55 ± 15 years, 60% women) completed the draft survey twice preoperatively, separated by an average of 4 days. In phase 3, 23 items were retained for the final survey. For retained items, the average weighted kappa value was 0.54 (Table). An overall score is calculated based on the number of expectations and the amount of improvement expected and ranges from 0-100, with higher scores indicating more expectations. For patients in phase 2, mean scores for both administrations were 65 and 66 and approximated normal distributions. Cronbach alpha coefficients were 0.88 and 0.90, and the intraclass correlation coefficient between scores was 0.78. Conclusion: We developed a patient-derived survey specific to foot and ankle surgery that is valid, reliable, and applicable to diverse diagnoses. It measures physical as well as psychological expectations, encompassing symptoms, function, mobility, work and social activities, exercise/sports, pain medications, shoewear, and appearance. The survey generates an overall score that is easy to calculate and interpret, and thus offers a practical and comprehensive way to record patients’ expectations. In the future, this survey may be used as a means to assess patient satisfaction with surgery as determined by the fulfillment of their expectations.

Fractional quantum Hall liquids exhibit a rich set of excitations, the lowest-energy of which are the magnetorotons with dispersion minima at a finite momentum. We propose a theory of the magnetorotons on the quantum Hall plateaux near half filling, namely, at filling fractions $\nu=N/(2N+1)$ at large $N$. The theory involves an infinite number of bosonic fields arising from bosonizing the fluctuations of the shape of the composite Fermi surface. At zero momentum there are $O(N)$ neutral excitations, each carrying a well-defined spin that runs integer values $2,3,\ldots$. The mixing of modes at nonzero momentum $q$ leads to the characteristic bending down of the lowest excitation and the appearance of the magnetoroton minima. A purely algebraic argument shows that the magnetoroton minima are located at $q\ell_B=z_i/(2N+1)$, where $\ell_B$ is the magnetic length and $z_i$ are the zeros of the Bessel function $J_1$, independent of the microscopic details. We argue that these minima are universal features of any two-dimensional Fermi surface coupled to a gauge field in a small background magnetic field., Comment: 5 pages, 2 figures; v3: published version

Background: Research regarding outcomes in sports and physical activities after primary partial arthrodesis for Lisfranc injuries has been sparse. The purposes of this study were to assess various sports and physical activities in young patients following primary partial arthrodesis for Lisfranc injuries and to compare these with clinical outcomes. Methods: Patients who underwent primary partial arthrodesis for a Lisfranc injury were identified by a retrospective registry review. Thirty-eight of 46 eligible patients (83%) responded for follow-up at a mean of 5.2 (range, 1.0 to 9.3) years with a mean age at surgery of 31.8 (range, 16.8 to 50.3) years. Physical activity participation was assessed with a new sports-specific, patient-administered questionnaire. Clinical outcomes were assessed with the Foot and Ankle Outcome Score (FAOS). Results: Patients participated in 29 different and 155 total physical activities preoperatively, and 27 different and 145 total physical activities postoperatively. Preoperatively, 47.1% were high impact, and postoperatively, 44.8% were high impact. The most common activities were walking, bicycling, running, and weightlifting. Compared to preoperatively, difficulty was the same in 66% and increased in 34% of physical activities. Participation levels were improved in 11%, the same in 64%, and impaired in 25% of physical activities. Patients spent on average 4.2 (range, 0.0 to 19.8) hours per week exercising postoperatively. In regard to return to physical activity, 97% of respondents were satisfied with their operative outcome. Mean postoperative FAOS subscores were significantly worse for patients who had increased physical activity difficulty. Conclusion: Most patients were able to return to their previous physical activities following primary partial arthrodesis for a Lisfranc injury, many of which were high-impact. However, the decreased participation or increase in difficulty of some activities suggests that some patients experienced postoperative limitations in exercise. Future studies could compare sports outcomes between primary partial arthrodesis and open reduction internal fixation for Lisfranc injuries. Level of Evidence: Level IV, retrospective case series.

Background: The modified Lapidus procedure has successfully relieved pain and corrected deformity in patients with hallux valgus, but its effect on participation in specific sports and physical activities remains unclear. Our goals were to assess sports and physical activities in young patients following the modified Lapidus procedure and to compare these with clinical outcomes. Methods: Fifty-eight eligible patients were identified from a retrospective registry review. Of these, 48 (83%) were reached for follow-up at a mean of 2.8 (range, 1.0 to 6.1) years and had a mean age at surgery of 37.3 (range, 14.1 to 49.3) years. Physical activity participation was evaluated with a new sports-specific, patient-administered questionnaire. Clinical outcomes were evaluated with the Foot and Ankle Outcome Score (FAOS) and compared to sports outcomes. Results: Patients participated in 26 different physical activities, consisting of 212 total physical activities preoperatively and 209 total postoperatively. The most common were walking, running, bicycling, and swimming. Compared to preoperatively, patients rated 29% of activities as less difficult, 52% as the same, and 19% as more difficult and rated participation levels as improved in 40%, the same in 41%, and impaired in 19%. Eighty-one percent of patients were satisfied with their operative outcome in regard to return to physical activity. Changes in the FAOS Pain subscore were significantly associated with improvements in physical activity difficulty ( P < .05), and changes in the Pain, Sports, and QOL subscores were significantly associated with changes in physical activity participation levels ( P < .05). Conclusion: Four in 5 patients were able to participate in previous sports and physical activities, including high-impact activities, at their preoperative participation level or better after the modified Lapidus procedure, and were satisfied with surgery in regard to return to previous activity. However, several patients had increased difficulty and impaired participation in physical activity postoperatively. Altogether, this suggests that the procedure is a viable treatment option for hallux valgus in young, active patients. Level of Evidence: Level IV, retrospective case series.

Category: Other Introduction/Purpose: Neuraxial anesthesia is often viewed as superior to general anesthesia (GA), but there are concerns that it may prolong length of stay (LOS). Most studies comparing the two anesthesias were performed in the absence of peripheral nerve blocks (PNBs), which when used as an analgesic adjunct may overcome the associated negative side effects of GA and allow decreased LOS. We hypothesized that patients given PNBs and GA would be discharged sooner than patients given PNBs and spinal anesthesia plus sedation, without increased incidence of adverse side effects such as pain, opioid administration and nausea. Methods: A single-center triple-blinded randomized controlled trial of 36 consecutive patients receiving elective F&A surgery predicted to take 1-3 hours under planned PNB with either spinal or GA was performed (see table 1. for demographics).The primary outcome was time to meet criteria for home discharge. The a priori clinically relevant difference with 80% power was determined to be 45 minutes. Patients were assessed after admission to the PACU and at 15-minute intervals thereafter. Once an Aldrete score=9 (scale signifying patient no longer needs intensive monitoring) was obtained, patients were transferred to Phase II and assessed until the post anesthesia discharge scoring system, a home readiness scale, was =9. Actual time to discharge was also recorded.Additional outcomes included a series of baseline characterizations which were assessed pre-and post-operatively, and again during Phase II.The primary outcome was compared using multivariable unconditional quantile regression. Various regressions were performed on secondary outcomes. Results: After adjustment for age and surgical duration, patients given GA plus PNB were ready for discharge from PACU 39 minutes prior to patients given neuraxial anesthesia plus PNB, but this difference did not reach the clinically relevant a priori selected difference of 45 minutes (Table 1). However, the adjusted median time to meet ambulation discharge criteria was 52 minutes fewer (p = 0.003) (Table 1). Patients met discharge criteria substantially sooner than their time until actual discharge which was not different between groups (Table 1). Pain scores at rest were higher among GA patients at 1 hour in the PACU (adjusted difference in means [95% CI]: 2.1 [1.0, 3.2], p < 0.001). Subsequent pain scores and all other secondary outcomes were not different. Conclusion: GA with PNB patients were ready for discharge 39 minutes earlier, but that difference may not be clinically significant. Although patients met criteria for discharge sooner due to a significantly more rapid ability to ambulate, they were not discharged sooner because PACU staff was not acclimated to the earlier readiness and so did not push for earlier discharge. These findings suggest that GA plus PNB leads to earlier discharge with similar side effects as spinal plus PNB. Therefore, the use of GA with PNB for foot and ankle surgeries could save the hospital and the patient time and resources.

Background: In 2003, a limited survey regarding the number of dedicated foot and ankle faculty and foot and ankle rotations at orthopaedic surgery residency programs was published. The purpose of this paper was to update the results of that previous survey and provide additional, more in-depth information. Materials and Methods: A survey questionnaire was emailed to the program directors and chairpersons of the 150 ACGME-accredited orthopaedic residency training programs in the United States. Results: Responses were obtained from all programs. One hundred thirty-seven (91.3%) programs had one or more orthopaedic surgeon faculty members with a predominantly foot and ankle practice (at least 50%), an increase of 5.5 percentage points from the survey performed 6 years previously. One hundred forty three (95.3%) programs had one or more orthopaedic surgeon faculty members with a practice consisting of at least 25% foot and ankle. One hundred twenty programs (80%) had one or more dedicated foot and ankle rotations, an increase of 15.1% from 6 years prior. Orthopaedic surgery residents were felt to spend a mean of 30.4% and a median of 20% of their time with board-certified/ board-eligible orthopaedic surgeons in rotations that include treatment of foot and ankle pathology but were not considered “dedicated” foot and ankle rotations. Conclusions: The number of orthopaedic surgery residency programs with rotations and faculty members dedicated to foot and ankle education has increased over the 6 years between surveys. Orthopaedic surgery residents’ experience and skill development in foot and ankle surgery during their 5 years of residency training are not limited to their time spent in dedicated foot and ankle rotations.

For a spacetime of odd dimensions endowed with a unit vector field, we introduce a new topological current that is identically conserved and whose charge is equal to the Euler character of the even dimensional spacelike foliations. The existence of this current allows us to introduce new Chern-Simons-type terms in the effective field theories describing relativistic quantum Hall states and (2+1) dimensional superfluids. Using effective field theory, we calculate various correlation functions and identify transport coefficients. In the quantum Hall case, this current provides the natural relativistic generalization of the Wen-Zee term, required to characterize the shift and Hall viscosity in quantum Hall systems. For the superfluid case this term is required to have nonzero Hall viscosity and to describe superfluids with non s-wave pairing., Comment: 24 pages. v2: added citations, corrected minor typos in appendix

We consider non-relativistic curved geometries and argue that the background structure should be generalized from that considered in previous works. In this approach the derivative operator is defined by a Galilean spin connection valued in the Lie algebra of the Galilean group. This includes the usual spin connection plus an additional "boost connection" which parameterizes the freedom in the derivative operator not fixed by torsion or metric compatibility. As an example we write down the most general theory of dissipative fluids consistent with the second law in curved non-relativistic geometries and find significant differences in the allowed transport coefficients from those found previously. Kubo formulas for all response coefficients are presented. Our approach also immediately generalizes to systems with independent mass and charge currents as would arise in multicomponent fluids. Along the way we also discuss how to write general locally Galilean invariant non-relativistic actions for multiple particle species at any order in derivatives. A detailed review of the geometry and its relation to non-relativistic limits may be found in a companion paper [arXiv:1503.02682]., Comment: Reference added. 44 pages

There is significant recent work on coupling matter to Newton-Cartan spacetimes with the aim of investigating certain condensed matter phenomena. To this end, one needs to have a completely general spacetime consistent with local non-relativisitic symmetries which supports massive matter fields. In particular, one can not impose a priori restrictions on the geometric data if one wants to analyze matter response to a perturbed geometry. In this paper we construct such a Bargmann spacetime in complete generality without any prior restrictions on the fields specifying the geometry. The resulting spacetime structure includes the familiar Newton-Cartan structure with an additional gauge field which couples to mass. We illustrate the matter coupling with a few examples. The general spacetime we construct also includes as a special case the covariant description of Newtonian gravity, which has been thoroughly investigated in previous works. We also show how our Bargmann spacetimes arise from a suitable non-relativistic limit of Lorentzian spacetimes. In a companion paper [arXiv:1503.02680] we use this Bargmann spacetime structure to investigate the details of matter couplings, including the Noether-Ward identities, and transport phenomena and thermodynamics of non-relativistic fluids., v5: update references. matches version published in JMP v4: minor text changes. version accepted in Journal of Mathematical Physics v3: improved discussion of NR limit and added refs, v2: updated references and text. v1: 39 pages, 2 figures

Motivated by the observation of the fractional quantum Hall effect in graphene, we consider the effective field theory of relativistic quantum Hall states. We find that, beside the Chern-Simons term, the effective action also contains a term of topological nature, which couples the electromagnetic field with a topologically conserved current of $2+1$ dimensional relativistic fluid. In contrast to the Chern-Simons term, the new term involves the spacetime metric in a nontrivial way. We extract the predictions of the effective theory for linear electromagnetic and gravitational responses. For fractional quantum Hall states at the zeroth Landau level, additional holomorphic constraints allow one to express the results in terms of two dimensionless constants of topological nature., 4 pages

Category: Other Introduction/Purpose: Few authors have investigated patients’ expectations from foot and ankle surgery, and standardized means of assessing expectations are lacking. Managing patients’ preoperative expectations may help improve their ultimate satisfaction with surgery. In a previous study (in press), we developed a valid and reliable patient-derived expectations survey for patients undergoing foot and ankle surgery. In this study, we aimed to examine relationships between patients’ preoperative expectations and their demographic and clinical characteristics. We hypothesized that patients with more disability and those with anxiety or depressive symptoms would have greater expectations. Methods: All adult patients scheduled for elective foot or ankle surgery by one of six orthopaedic foot and ankle surgeons were screened for inclusion over eight months. Preoperatively, patients completed the Foot & Ankle Surgery Expectations Survey in addition to the Foot & Ankle Outcome Score (FAOS), Short Form (SF)-12, Patient Health Questionnaire (PHQ)-8, Generalized Anxiety Disorder 7-item scale (GAD-7), and pain visual analog scale (VAS). The expectations survey contains 23 expectations categories, each with five answer choices ranging from I do not have this expectation to complete improvement expected. It is scored from 0-100; higher scores indicate greater expectations. Differences in expectations score with categorical variables were assessed with t-tests and single factor analysis of variance (ANOVA). Differences in number of expectations and number of expectations with complete improvement expected were assessed with Mann-Whitney U and Kruskal Wallis tests. Relationships between expectations and continuous variables were assessed with linear regression. Results: 352 patients (average age 55 ± 15, range 18 to 86) were enrolled. Expectations were not significantly related to age. Women expected to achieve complete improvement more often than men (p = 0.011). Other factors significantly associated with higher expectations (p < 0.05) included non-Caucasian race, workers’ compensation, use of a cane or other assistive device, diagnosis of ankle instability or osteochondral lesion, and greater medical comorbidity (Table). Patients with a history of prior orthopaedic surgery were less likely to expect complete improvement. Worse function and quality of life (as assessed by all FAOS subscales and SF-12 physical and mental components), more depressive and anxiety symptoms, and higher pain VAS scores were associated with higher expectations scores and more expectations (p < 0.001 for all). Conclusion: The results of this study may help inform surgeons’ preoperative discussions with their patients regarding realistic expectations from surgery. Generally patients with worse function and more disability had higher expectations from surgery. Addressing these patients’ expectations preoperatively may help improve their ultimate satisfaction with surgery.

We review and extend previous results regarding the stability and thermodynamics of Anti-de Sitter (AdS) spacetime at finite temperature. Using a combination of analytic and numerical techniques, we compute the energy, temperature, and entropy of perfect fluid stars in asymptotically AdS spacetimes. We find that at sufficiently high temperature (in the canonical ensemble) or energy (in the microcanonical ensemble) these configurations develop dynamical instabilities, which presumably lead to the formation of a black hole. We extend our analysis to the case of $AdS \times S$ compactifications stabilized by flux (such as those that arise in supergravity and string theory), and find that the inclusion of the sphere does not substantially alter these results. We then map out the phase structure of these theories in the canonical and microcanonical ensembles, paying attention to inequivalence of these ensembles for global anti-de Sitter space. With a certain scaling limit, the critical temperature can be parametrically lower than the string temperature, so that supergravity is a good description at the instability point. We comment on the implications of this for the unitarity of black holes., 39 pages, 13 figures