Short Leg Research Articles

Man versus Machine Learning: The Term Structure of Earnings Expectations and Conditional Biases

Abstract We introduce a real-time measure of conditional biases to firms’ earnings forecasts. The measure is defined as the difference between analysts’ expectations and a statistically optimal unbiased machine-learning benchmark. Analysts’ conditional expectations are, on average, biased upward, a bias that increases in the forecast horizon. These biases are associated with negative cross-sectional return predictability, and the short legs of many anomalies contain firms with excessively optimistic earnings forecasts. Further, managers of companies with the greatest upward-biased earnings forecasts are more likely to issue stocks. Commonly used linear earnings models do not work out-of-sample and are inferior to those analysts provide. Authors have furnished an Internet Appendix, which is available on the Oxford University Press Web site next to the link to the final published paper online.

Multifocal percutaneous pin fixation of talar neck fractures: An alternative to ORIF in the polytraumatized patient

PurposeUnique anatomy, precise articulations, fragile vascularity, and the demand for anatomic reduction make talar neck fractures challenging to treat, whether with screws and/or plates. Multifocal percutaneous pin fixation (MPPF) offers an alternative to ORIF, particularly in the polytraumatized patient. MethodsUnless an open lateral wound or medial malleolus fracture was present, a standard anteromedial approach was performed. K-wires placed within the talar head were used as joysticks to facilitate and finalize reduction. At least 3 wires were placed medially and 2 laterally across the talar neck. Incisions were closed in 2 layers, and either a well-padded short leg splint or adjunctive ankle-spanning external fixation was utilized. Patients remained non-weightbearing until K-wire removal in the office at approximately 6–8 weeks postoperatively. ResultsMPPF was performed in 7 patients, the majority of whom were female (6 of 7). The average patient age at the time of injury was 30.3 years (range 17–51 years). The median time of final follow up was 27 months. Comminution was present in all patients. Avascular necrosis (AVN) developed in 3 patients and non-union occurred in 2 patients. All patients developed subtalar posttraumatic arthritis, and 6 additionally developed tibiotalar arthritis. No patients underwent talectomy or osteotomy, and there were no superficial pin site infections or loosening of pins prior to scheduled removal. ConclusionsObtaining and maintaining an adequate reduction is possible with minimal soft tissue compromise through MPPF. Despite the complexity of the series, outcomes utilizing MPPF are comparable to those reported in the literature.

Proximal Flexor Hallucis Longus Transfer to Peroneus Brevis for Treatment of Peroneal Muscle Paralysis

Category: Hindfoot; Ankle; Other Introduction/Purpose: Equinovarus foot deformities typically present with equinus contractures, hindfoot varus, dorsiflexion of the medial midfoot, and adduction deformities of the forefoot. Whether of neurologic or muscular origin, all forms result muscular imbalance. Flexor hallucis longus (FHL) transfer to peroneus brevis (PB) is indicated when both peroneal muscles are in unrepairable condition to restore active eversion. However, in cases of muscle paralysis where the PB is still in continuity, we recommend a novel technique where FHL is tenodesed proximal to the peroneal retinaculum within the leg to avoid the additional morbidity associated with more distal fixation or tenodesis. Methods: Surgical intervention first involved a posterolateral approach to the ankle and an Achilles tendon Z-lengthening to fix her equinus contracture. The ankle and subtalar joint capsules were contracted requiring release. Flexor digitorum longus (FDL) and FHL were tenotomized, which immediately corrected her claw toes. Since the tendon had already been released, we were able to deliver the FHL tendon into the posterolateral leg wound. The peroneal fascia and sheath were opened proximal to the superior peroneal retinaculum to prevent tendon subluxation. PB was identified by confirming that it produced foot eversion and by visualizing the peroneus longus (PL). The tension of PB was confirmed by observing that it did not cause tension at PL insertion on the plantar 1st ray. FHL was then transferred to the PB utilizing a Pulvertaft weave technique with the tendon appropriately tensioned in mid eversion in the middle of the Blix curve (Figure 1). Results: After FHL transfer, the patient was immediately allowed to weight bear as tolerated in a short leg cast. This was due to her deconditioned state to limit atrophy and the effects of prolonged recumbency in this medically fragile young woman. The patient ultimately was casted for 10 weeks total as she was unable to tolerate a CAM boot or other orthotic due to the weight and problems with the fit. At 4 months follow up, her foot is corrected and she is able to stand in a neutral, plantigrade position. Using a new AFO, she can walk without issue. Her foot remains well balanced and plantigrade. Conclusion: This simple FHL transfer technique decreases morbidity since the transfer occurs within the leg, proximal to the superficial peroneal retinaculum (SPR). The transfer pulls on the paralyzed, but intact PB instead of routing the FHL to the 5th metatarsal base or PB stump. This technique is only recommended if PB is intact but non-functional. It should be noted that adequate tensioning is essential for a successful transfer. Benefits of this procedure include no cluttering under the SPR and no risk of scarring that region which can lead to decreased tendon excursion.

Acute Deep Deltoid Ligament Reconstruction using a Novel, Arthroscopically-Assisted Technique: Case Report

Category: Arthroscopy; Ankle; Sports; Trauma Introduction/Purpose: The deltoid ligament complex is the main stabilizing structure of the ankle mortise and is often disrupted in rotational ankle injuries. Current treatment involves open techniques for the acute repair of the superficial deltoid layer, however, repair or reconstruction of the deep deltoid ligament (DDL) has proven to be challenging using open techniques. Our described arthroscopically-assisted technique allows for better intra-articular visualization and durable reconstruction of the ruptured DDL with suture and knotless bone anchors. The goal of this new, minimally invasive approach is to facilitate a faster and more reliable recovery and prevent long-term dysfunction and degeneration from medial and rotational ankle instability. We believe it has the potential to provide improved immediate ankle stability and decrease overall surgical morbidity compared to open treatments. Methods: Case of a 48-year-old male with ligamentous-equivalent Massioneuve fracture with medial clear space (MCS) measuring 11 millimeters. Arthroscopy revealed unstable syndesmosis and rupture of the DDL. After syndesmotic fixation, there was persistent MCS widening on stress exam. Arthroscopically-assisted DDL reconstruction was performed using an accessory anteromedial (AAM) portal between the tibialis anterior tendon and posterior tibial tendon. Needle localization identified the sagittal midpoint of the medial wall of the talus, inferior to articular cartilage. Anchor sites at both the medial talar wall and midportion of the distal medial malleolus (insertion and origin of the DDL, respectively) were then drilled via the AAM portal under arthroscopic and fluoroscopic guidance respectively at the isometric point. A suture anchor was placed into the talus and tails were loaded and secured to the medial malleolus with a bioabsorbable anchor. Ankle mortise was stable to stress exam and there were no restraints to physiologic motion. Results: The patient was kept non-weight bearing on his right lower extremity for a total of 6 weeks postoperatively and was seen in the clinic for routine follow-up visits at 2 weeks, 6 weeks, and 3 months post-procedure. Sutures were removed at 2 weeks, without any wound complications, and he was transitioned from splint to a short leg cast. He required only three days of oral narcotic analgesia. Weight-bearing in a controlled ankle motion (CAM) boot and physical therapy were both initiated at 6 weeks post-op. Radiographs at each follow-up visit were without abnormalities. At 3 months post-op, he was graduated from the CAM boot into a lace-up ankle brace, without any complaints of ankle pain or instability. The patient progressed well with full weight-bearing and physical therapy and was seen for a final visit at 5 months post-op with stable MCS. No complications were encountered. Conclusion: Acute DDL rupture is a common occurrence in ankle fractures and can be diagnosed radiographically and by arthroscopy. Known sequelae of untreated DDL disruption include medial instability and late valgus collapse. This case report demonstrates a novel, minimally invasive technique to successfully reconstruct the DDL, which may minimize the surgical morbidity compared to open dissection methods and allow for decreased recovery time postoperatively. This approach may also be utilized for cases of chronic instability. Future work includes larger case series with long-term follow-up and refinement of the technique as instrumentation advances.

Is Phenotypic Evolution Affected by Spiders' Construction Behaviors?

What happens when organisms actively modify their environment? Clarifying the role of construction behavior on a macroevolutionary scale is crucial to interpreting phenotypic evolution. Spiders, an extremely successful group of animals exhibiting a wide variety of functional, morphological, and behavioral diversity, are ideal candidates to test whether animal behaviors are related to their phenotypic evolution. Herein, we reconstructed the phylogenomic relationships of 303 spiders covering 105 families with 99 newly developed molecular markers that universally apply across Araneae, and explicitly tested the potential link between construction behavior and somatic evolution based on extensive morphological data from 3,342 extant species and 682 fossil species. Our dated molecular phylogeny provides the backbone for analyses, revealing the behavioral and ecological processes behind these spiders' morphological adaptations. Evolutionary model analyses showed the artifacts constructed by spiders, especially the suspending webs, expand the spider's ability to inhabit different habitats. These artifacts have more substantial impacts on their somatic traits than habitats and promote different trajectories of morphological evolution. Specifically, for spiders, silk-lined burrowing produced larger bodies, relatively shorter legs, and longer patellae, while web-building produced smaller bodies, relatively longer legs, and shorter patellae, and hunting promoted an intermediate morphological size. Molecular convergence analysis showed that genes related to morphogenesis or response to stimulus and stress are enriched in spiders with construction behavior. Our study demonstrated that the construction behavior of an animal plays a crucial role in determining the direction and intensity of the selection pressure imposed on it and provides strong evidence that construction behaviors are associated with phenotypic evolution on macroevolutionary timescales. [Araneae; body size; habitat change; molecular marker; leg length; phylogenomics.].

An Unusual Case of Swimmer Puppy Syndrome in Labrador Puppy

Swimmers puppy syndrome is an uncommon developmental deformity seen in neonatal puppies and kittens, in which animal's limbs, most commonly hind limbs, are splayed laterally, and because of that animals are unable to walk or stand. This condition may also affect the thoracic limb. It is also called flat pup syndrome, twisted legs, turtle pup, and splay leg. This condition is commonly seen in brachycephalic breeds having short legs and a broad thoracic cavity. When trying to walk, affected animals invariably stay in sternal recumbency and show swimmers-like movements and this movement is more commonly seen on the smooth surface. The exact cause of this condition is unknown but many predisposing factors are responsible, viz., slippery floor, delayed neuromuscular development, abnormal myelinization, genetic factor, weight gain exceeding skeletal muscle development, etc. This condition is commonly seen at the 1st to 7th week of age. Currently, there is no specific and set protocol for the treatment of Swimmer Puppy Syndrome. To our knowledge, the few case studies described therapies based on the implementation of temporary immobilizations utilizing eight-girdle or cuff bandages and intensive physical therapy. (Karcher et al., 2018).

Painting the black box white: Interpreting an algorithm-based trading strategy

Difficulty understanding how a black box model makes predictions undermines machine learning's success in financial markets. We show how to employ model-agnostic methods to carry out machine learning stock market predictions that are more transparent to a human investor. We create long-short investment strategies using a tree-based fundamental analysis. We apply the models to the Brazilian stock market, achieving an out-of-sample expected annual return of 26.4% with a Sharpe ratio of 0.50. Ensembles between the long and short legs improve Sharpe ratio up to 1.26. Our strategy has low asset turnover and hence transaction costs do not harm performance too much. Interpretation shows differences in the main drivers of over- and underperformance.

Two Orthogonal Nitinol Staples and Combined Nitinol Staple-Screw Constructs for a First Metatarsophalangeal Joint Arthrodesis: A Biomechanical Cadaver Study.

End-stage hallux metatarsophalangeal (MTP) joint arthritis is commonly treated with arthrodesis using stainless steel or titanium implants. These implants provide static compression that is maximal at the time of implant insertion. Alternatively, nitinol staples are capable of dynamic compression. They have most frequently been used for midfoot arthrodesis procedures. However, their biomechanical performance during hallux MTP arthrodesis has not been described. 8 matched pairs of cadaveric feet (4 female, 4 male) were prepared for hallux MTP arthrodesis using cup and cone reamers. Cadaveric pairs were then instrumented with either (1) a transarticular lag screw and dorsal nitinol staple or (2) orthogonal nitinol staples placed dorsally and medially. Walking in a short leg cast for 6 weeks was simulated by applying 90-N forces at 3 Hz to the plantar proximal phalanx for up to 250 000 cycles. Failure was defined as catastrophic implant failure or plantar gapping beyond 7 mm. 15 of 16 specimens failed cyclic loading. All 8 specimens fixed with orthogonal staples failed at an average of 37 ± 81 cycles. 7 of 8 specimens fixed with a dorsal staple and crossed screw failed at 14 900 ± 39 000 cycles. Collectively, 5 specimens failed because of bone fracture (1 in orthogonal staples, 4 in staple-screw group) and 10 failed because of excessive gap formation (7 in orthogonal staples, 3 in staple-screw group). The number of cycles to failure was significantly lower (P = .0469) in the orthogonal staple constructs compared with the dorsal staple and crossed screw constructs. The tested constructs permit significant motion at the first MTP fusion surface during simulated protected weightbearing. Although multiple in vivo factors should be considered when extrapolating results from this cadaveric study, this motion may result in clinical failure with early postoperative weightbearing protocols. We report the first biomechanical evaluation of hallux MTP arthrodesis using modern nitinol staples in 2 separate constructs.

Up and down together? On the linkage of momentum and reversal

This paper presents evidence of momentum and reversal being related phenomena in the German stock market. This finding contrasts Conrad and Yavuz's (2017) results for the US stock market. In the German stock market, the linkage of both phenomena is documented to be more pronounced after the turn of the millennium. In particular, low-risk stocks produce momentum, and high-risk stocks generate return reversal in momentum portfolios. Short-run momentum is consistently generated by the long winner leg, whereas long-run return reversal is due to the short loser leg of long-short portfolios in the German stock market.

Craniofacial Manifestation and Orthosurgical Management of a Patient with Achondroplasia

Achondroplasia is a bone growth disorder results due to failure in endochondral ossification, conversion of cartilages into mature bones. It is the most common metaphyseal dysplastic condition of long bones. The incidence of achondroplasia is 1:25000–30,000 of live births. Our patient was a diagnosed case of achondroplasia, characterized by short stature, disproportionately short arms and legs, and short fingers. Craniofacial features include prominent forehead (frontal bossing), short cranial base, short nose, depressed nasal bridge, short upper lip leading to increased incisal show along with gingival visibility and hyperactive mentalis. Intraoral examination revealed constricted maxillary arch, multiple missing teeth, increased overjet of 12 mm, nonspecific molar, and canine relation bilaterally. Therapeutic intervention included orthosurgical management, i.e., Stage I (presurgical orthodontics)-leveling and alignment followed by closure of extraction spaces; Stage II (surgical management)–le fort-1 osteotomy and maxillary superior repositioning of 6 mm followed by 5 mm bilateral sagittal split ramus osteotomy with anticlockwise rotation of body of the mandible; and Stage III–settling of occlusion and fixed retention in maxillary and mandibular arch. Present case highlights the craniofacial manifestations of achondroplasia its effective management and the potential complications associated. Treating orthodontist should be aware of these features and their consequences in managing the patient to achieve a successful outcome.

Pure Ankle Dislocation Without Associated Fracture: A Series of Cases and Our Clinical Experience.

Pure ankle dislocation without associated fracture is extremely rare. The current study reports eight cases of this type of injury, aiming to add some new material to the published data and present our clinical experience. Six open and two closed posteromedial tibiotalar dislocations without associated fractures treated in our department from 2015 to 2019 were retrospectively analyzed. Emergent reduction was performed for all patients followed by an average of 6weeks of immobilization with external fixators in open cases and a short leg cast in closed cases. No patients underwent ligament or capsule repair except one case. The clinical data were recorded and analyzed. At a mean follow-up of 33months (range 13-61), the average AOFAS score was 91 (range 78-100) with five ankles rated as excellent and three rated as good. All of the eight patients returned to their prior daily life and the two closed patients with sports injuries resumed pre-injury activity level. The average range of motion (ROM) loss of the ankles was 9 degrees for plantarflexion and 3 degrees for dorsiflexion. Complications included superficial infection, moderate ankle stiffness, ankle degenerative change and residual numbness. None of the eight patients showed obvious ankle instability. Pure ankle dislocation without associated fracture is a rare injury. Emergent reduction, appropriate wound care in open injuries and proper joint stabilisation with a cast or external fixator provide good clinical results and could be the mainstay of treatment.

Should Diastatic Syndesmosis be Stabilized in Advanced Pronation-External Rotation Ankle Injuries? A Retrospective Cohort Comparison.

ObjectiveWith or without screw stabilization for diastatic syndesmosis in advanced pronation‐external rotation (PE) ankle injuries has not yet been well‐determined. Both techniques were retrospectively compared to investigate the superiority of either of the two.MethodsA retrospective cohort study was carried out. From January 1, 2008, to December 31, 2017, 81 consecutive adult patients (average, 42 years; range, 18–78 years; 44 men and 37 women) with advanced PE ankle injuries (stage 3 or 4 PE type) were treated. After malleolar fractures were internally stabilized with screws and plates, the syndesmotic stability was rechecked by external rotation and hook tests. The necessity of cortical screw insertion to stabilize diastatic syndesmosis was decided by the individual orthopaedic surgeon. Postoperatively, a short leg splint was used for 6 weeks. The syndesmotic screw was removed based on the surgeon's policy. The removal of internal fixation for malleolar fractures was required after 1 year. The outcomes of both approaches were compared clinically, and ankle function was compared using the American Orthopaedic Foot and Ankle Society (AOFAS) score. For statistical comparison, the chi‐square test was used for categorical data and the Mann–Whitney U test was used for numerical data.ResultsSeventy‐one patients (average, 40 years; range, 18–78 years; 40 men and 31 women) were followed for at least 1 year (87.7%; average, 2 years; range, 1–11 years). Group 1 (with syndesmotic stabilization) had 22 patients and Group 2 (without syndesmotic stabilization), 49 patients. The union rate in Group 1 patients was 100% (22/22), and in Group 2 patients, 91.8% (45/49; p = 0.17). One deep wound infection occurred in Group 1 patients and two in Group 2 patients. Syndesmosis re‐diastasis occurred in 13.6% (3/22) of Group 1 patients and 30.6% (15/49) of Group 2 patients (p = 0.13). One syndesmotic screw broke at 6 months. Satisfactory ankle function according to the AOFAS score was noted in 86.4% (19/22) of Group 1 patients and 65.3% (32/49) of Group 2 patients (p = 0.07).ConclusionInsertion of syndesmotic screws to promote ligament healing after internal fixation of malleolar fractures in advanced PE ankle injuries may be reasonable.

Three new troglobitic Coarazuphium (Coleoptera, Carabidae, Zuphiini) species from a Brazilian hotspot of cave beetles: exploring how the environmental attributes of caves drive ground-beetle niches

Three new species of troglobitic beetles of the genusCoarazuphiumare described from specimens collected in iron ore caves in the Flona de Carajás in Brazil, doubling the number of known species for the Carajás region. The new species ofCoarazuphiumare morphologically similar to the already described species from the same region and are distributed in a small geographic range. From allCoarazuphiumspecies of the region, including the new ones, two stand out,C. spinifemurandC. xingusp. nov., which are the smallestCoarazuphiumspecies. Both species have shorter legs and antennae when compared to the others. The main characteristic that differentiatesC. xikrinsp. nov.andC. kayaposp. nov.from the other two species from the Carajás region,C. tapiaguassuandC. amazonicum, is that the new species have more numerous setigerous punctures dorsally on the head. With the three new species added to the six already described congeners, the area of intense mining of the Carajás region includes the highest diversity of obligatory cave-dwelling beetles in Brazil, representing a hotspot of cave beetles.Coarazuphium xikrinsp. nov.andC. amazonicumco-occur in some of the caves of the Carajás region, which is possible due to putative niche differentiation between the species. These findings highlight the importance of maintaining legal provisions that ensure the preservation of caves, especially those most relevant regarding physical and biotic aspects, which is crucial for the conservation of Brazilian subterranean biodiversity.

Closed isolated anterolateral calcaneal dislocation: a case report

BackgroundComplete isolated calcaneal dislocation, defined as dislocation of talocalcaneal and calcaneocuboid joints with intact talonavicular joint without significant fracture, is an exceedingly rare injury.Case presentationA 49-year-old man, after a motor vehicle collision, presented with a closed isolated anterolateral dislocation of the calcaneus associated with fracture of the sustentaculum tali, cuboid, lateral process of the talus, and avulsion fracture of superior peroneal retinaculum. Urgent successful closed reduction was immediately performed in the emergency room under sedation. Two days later, through sinus tarsi approach extended proximally to posterior of the lateral malleolus and distally to the calcaneocuboid joint, peroneal tendons were reduced in the retromalleolar groove and avulsion fracture of the superior peroneal retinaculum was reduced and fixed by a suture anchor. A chondral lesion (6 × 8 mm) was seen in the posterior facet of the calcaneus for that chondroplasty and microfracture were performed. Also, small bony fragments from the cuboid were excised. The reduced calcaneocuboid joint was fixed by two Kirschner wires. In the second stage, 10 days later, through medial approach to the talocalcaneal joint, multiple free bony fragments were excised. Then sustentaculum tali was reduced and fixed using a lag screw. Postoperatively, a non-weight bearing short leg cast was applied for six weeks. The patient had permission to start partial weight bearing 6 weeks after removal of K-wires. Finally, at the 10th postoperative week, he had full weight-bearing without any aid instrument. He was able to return to his regular activities about 6 months after the injury. At 34 months, the American Orthopaedic Foot and Ankle Society ankle-hindfoot scale was 92 from 100. The foot function index percentile was 7% and the visual analogue score for pain was 1.9. The last radiographs revealed normal configuration of talocalcaneal, calcaneocuboid, and talonavicular joints with a little joint space narrowing in posterior part of the subtalar joint.ConclusionPatients with isolated anterolateral calcaneal dislocations, even with multiple associated fractures, can have acceptable outcomes, if it is urgently diagnosed and properly managed.

Another mite species discovered via social media - Ameronothrus retweet sp. nov. (Acari, Oribatida) from Japanese coasts, exhibiting an interesting sexual dimorphism

ABSTRACT The recent discovery of the oribatid mite Ameronothrus twitter via a social media platform resulted in a considerable media response and raised the awareness of the public for these tiny organisms. As a direct consequence, another new marine associated ameronothroid species was now discovered via the same social media service. Moreover, the record of this new species, Ameronothrus retweet sp. n., represents the first report of an ameronothroid taxon from the Sea of Japan coast, indicating that this coastline was successfully colonized by these organisms and that further species could be present there. Ameronothrus retweet sp. n. shows an extraordinary sexual dimorphism with females having relatively shorter legs and a strongly folded notogastral integument. Based on morphological characteristics, it is suggested that the new species is closest related to Ameronothrus lineatus and Ameronothrus nigrofemoratus. A molecular genetic investigation of selected ameronothroid taxa, using the 18S rRNA gene, shows that all Ameronothrus species are closely related and represent a distinct monophyletic genus. In a larger phylogenetic context, the Fortuyniidae and Selenoribatidae are given as sister taxa with a monophyletic origin, whereas certain members of Ameronothridae are placed in paraphyletic positions, supporting theories of an independent origin of the marine associated lifestyle in ameronothroid mites. http://www.zoobank.org/urn:lsid:zoobank.org:pub:D0D9B80E-D144-436D-82B1-F2847178E861 http://www.zoobank.org/urn:lsid:zoobank.org:act:0CFB4401-1EC4-4BB8-97CD-13812FF11D83

Casting and Splinting Options for Pseudo-Jones Avulsion Fractures: An Evidence-to-Practice Review

Avulsion fractures of the 5th metatarsal bone occur when a portion of the bone is broken or pulled off the rest of the bone. These fractures are often seen in athletes, especially those of a young age. Fractures of the 5th metatarsal bone are more commonly treated non-surgically with immobilization of the foot. There are several different options for immobilization of the foot with no clear result as to which immobilization method is the most effective. The purpose of this evidence to practice review was to summarize a systematic review on comparative outcomes of immobilization interventions on avulsion fractures of the 5th metatarsal. The authors included five studies in this review that compared two intervention methods. The two main interventions compared were short leg casting and splinting of the foot, and the authors reviewed foot function scores and non-union rates of the foot. It was found that foot function scores were greater in the splinting intervention groups, as well as a lower non-union rate of the 5th metatarsal bone. From the results of this systematic review, we recommend the use of a removable splint for avulsion fractures of the 5th metatarsal bone.

Effect of correction of leg length discrepancy on the biomechanical characteristics of the pelvis and hip joints among standing workers.

Few studies have reported the contribution of correction of leg length discrepancy (LLD) on the kinematic and kinetic characteristics of the pelvis and hip joints among those who must stand while working using shoe insoles and a three-dimensional (3D) motion analysis system. To investigate dynamic pelvic and hip joint angles and hip moments using a 3D motion analysis system with and without insoles in standing workers with LLD. Kinematic and kinetic data of 31 participants with LLD were collected using a motion analysis system and force platforms. Participants were asked to walk wearing standard shoes or shoes with LLD-corrected insoles. Repeated-measures analysis of variance (ANOVA) was used to compare the kinematic and kinetic data of the hip joints and pelvic orientation according to leg side and corrective interventions for LLD. There were significant differences in maximal ROM of hip adduction and abduction with vs. without LLD insoles in the longer and shorter legs (p < 0.05). There were significant differences in maximal elevation (p = 0.004) and total coronal motion (p = 0.006) of the pelvic segment with and without insole corrections in the longer leg during gait. LLD correction using a customized insole is a recommended therapeutic intervention to improve the musculoskeletal imbalances of hip and pelvic segments in workers with LLD.

Success Rate of Non-Operative Treatment of Insertional Achilles Tendinitis

Category:Hindfoot; OtherIntroduction/Purpose:Insertional Achilles tendinitis (IAT) is a common orthopedic condition that can be treated conservatively or surgically. While non-operative treatment is thought to be beneficial in approximately 50-70% of cases, the precise success rate of non-operative treatment is not fully defined in the current literature. The purpose of this study is to define the success rate of modern non-operative treatment of IAT more precisely.Methods:A retrospective chart review was performed to identify patients who received either surgical or non-surgical treatment of IAT with a single fellowship-trained foot and ankle surgeon at an academic medical center between September 2015 and June 2019. A total of 133 patients (137 ankles) were identified. The success rate of non-operative treatment, defined as the lack of need for surgical treatment within two years of initial diagnosis of IAT, was recorded. Patients with IAT were treated with scheduled anti-inflammatory medications, physical therapy with a focus on eccentric strengthening and Achilles stretching and, when needed, controlled ankle motion (CAM) boot, short leg casting, or Platelet-Rich Plasma injections for refractory cases. A demographic and comorbidity comparison was performed between groups. Statistical analysis was performed using two-tailed Student t-test and Chi-squared test.Results:There was no difference in treatment method between those successfully treated conservatively and those who went on to fail conservative management and require surgery. At first encounter, patients who later received surgery were significantly more likely to have higher VAS pain scores (surgery=6.54, conservative=5.10; p=.045) and lower SF-12 physical scores (surgery=25.16, conservative=35.61; p<.001). The overall success rate of non-operative treatment was 78.57% and the average time from initial diagnosis to surgery was 198.83 days (range, 28-486).Conclusion:Based on the results of this study, the success rates of non-operative treatment for IAT may be higher than what is traditionally thought, at just under 80%. Further, patients with worse VAS and SF-12 physical scores were significantly more likely to fail conservative management. Orthopedic surgeons should use this information to provide more accurate counseling on the most appropriate treatment strategies for IAT.

Effect of shoe insole on the dynamics of lower extremities in individuals with leg length discrepancy during walking

IntroductionThe aim of the present study was to investigate the effect of Internal and External Heel Lift Insoles (IHLI, EHLI) on pelvic kinematics and lower extremity joint moments in subject with mild leg length discrepancy (LLD) during the Stance Phase of walking. MethodsFrom twenty-eight men with mild LLD, kinematic and kinetic data were collected while they walked under each of three conditions (IHLI, EHLI and shoe). Data were collected for both limbs using a six-camera system synchronized with a force platform. For comparisons the dependent variables among the conditions, repeated measures ANCOVA and Bonferroni's post hoc test were used (P ≤ 0.05). ResultsFor both IHLI and EHLI, there were significant decreases in peak long leg lateral and anterior pelvic tilt, long leg hip and knee abduction moments, and short leg ankle plantar flexor moment (P ≤ 0.001). Furthermore, significant increases in peak lateral and anterior pelvic tilt of the short leg were observed in the IHLI and EHLI conditions as compared to the shoe (SH) condition (p ≤ 0.01). In addition, a significant difference was observed between the IHLI and EHLI conditions in the peak values of anterior pelvic tilt of the long leg (p = 0.043) and ankle plantar flexor moment of the short leg (p = 0.044). ConclusionFindings suggest that the use of IHLI and EHLI may be effective in improving pelvic movements (lateral and anterior tilt) and gait dynamics in individuals with LLD. The EHLI could reduce more the peak plantar flexor moment of the short leg and peak anterior pelvic tilt of the long leg than IHLI during stance phase of walking.

Attention and Underreaction-Related Anomalies

Recent studies have proposed a large set of powerful anomaly-based factors in the stock market. This study examines the role of investor inattention in the corresponding anomalies underlying these factors and other underreaction-related anomalies. Using media coverage as a proxy for investor attention, we show that the anomalies underlying many recently proposed prominent factors are much more pronounced among firms with low media coverage in portfolio-formation periods. In addition, we find many other prominent anomalies that previous literature has attributed to underreaction also tend to perform much better among firms with low media coverage. The average Fama-French five-factor alpha spread of these anomalies is about 0.97% per month among firms with low news coverage and only 0.24% per month among firms with high news coverage. Moreover, most of the alpha spread comes from the short leg of the anomalies and from the firms that are more difficult to arbitrage. Overall, our evidence indicates that investor inattention at least partially drives many of the recently proposed factors. This paper was accepted by Haoxiang Zhu, finance. Funding: L. Tao received financial support from the National Natural Science Foundation of China [Grant 72171050], the Ministry of Education Project of Humanities and Social Sciences [Grant No. 17YJCZH161], and the University of International Business and Economics Fund for Distinguished Young Scholars [Grant No. 18JQ07]. J. Yu acknowledges financial support from the National Natural Science Foundation of China [Grant No. 71790591]. Supplemental Material: The online appendix and data are available at https://doi.org/10.1287/mnsc.2022.4332 .