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Background Injury of the scapholunate interosseous ligament is the most frequently diagnosed cause of carpal instability and can be treated with a Mayo capsulodesis procedure. During this procedure, a radially based flap of the dorsal radiocarpal complex is attached to the lunate. The procedure attempts to reduce flexion of the scaphoid and restore the scapholunate relationship by crossing the scapholunate interval. To obtain a better understanding of the biomechanical properties and possibly improve the postoperative rehabilitation process, a better understanding of the reconstructions biomechanics is needed. Methods Ten dorsal intercarpal ligament capsulodesis were performed on embalmed wrists to assess the flexion elongation relation at the dorsal intercarpal reconstruction, the dorsal intercarpal complex, and the type of failure during flexion of the wrist. Results The mean elongation of the dorsal intercarpal reconstruction at 70-degree flexion was 0.8 mm. During flexion, the dorsal intercarpal reconstruction showed no ligament tears or failure of the bone anchor. The mean elongation of the dorsal intercarpal complex was 3.9 mm at 70 degrees. During subsequent repeated flexion, four sutures to connect the dorsal intercarpal complex to the surrounding tissue loosened between 55 and 60 degrees. Conclusions These findings suggest that capsulodesis can safely withstand flexion of the wrist until 50 degrees. Clinical Relevance Clinicians should consider the opportunity to start early with controlled active motion. Level of Evidence Not applicable.

Introduction: In this study, we compared the functionaloutcome of repair of cut flexor tendons using modified Kesslertechnique versus the four stands technique.Patients and Methods: Thirty Two adult patients withforty one severed flexor tendon underwent primary tendonrepair. In group A, we used two strands repair technique andin group B we used four strand repair technique. We usedearly controlled physiotherapy rehabilitation protocols forboth groups.Results: Regarding total active range of motion and DASHscore, there were no statistically significant differences betweenthe outcomes of these two groups. Tendon rupture occurredin one case in group A.Discussion: Primary tendon repair is the optimum treatmentfor cut flexor tendons. However, several repair techniquesand rehabilitation protocols exist. In vitro tests concluded thatthe more the strands that cross the repair site, the stronger therepair but in vivo studies did not reflect such benefits exceptthe four strands technique.Conclusion: We were not able to identify any statisticallysignificant differences in total active motion and DASH scoresbetween two and four strands repair techniques. However,the results of four strands technique were more favorable.

The prospect of self-propelled artificial machines small enough to navigate within biological matter has fascinated and inspired researchers and the public alike since the dawn of nanotechnology. Despite many obstacles toward the realization of such devices, impressive progress on the development of its basic building block, the nanomotor, has been made over the past decade. Here, we review this emerging area with a focus on inorganic nanomotors driven or activated by light. We outline the distinct challenges and opportunities that differentiate nanomotors from micromotors based on a discussion of how stochastic forces influence the active motion of small particles. We introduce the relevant light-matter interactions and discuss how these can be utilized to classify nanomotors into three broad classes: nanomotors driven by optical momentum transfer, photothermal heating, and photocatalysis, respectively. On the basis of this classification, we then summarize and discuss the diverse body of nanomotor literature. We finally give a brief outlook on future challenges and possibilities in this rapidly evolving research area.

Active heave compensation systems are typically single-degree-of-freedom systems that operate vertically to attenuate the vertical effects of wave motion. To apply compensation to towed bodies, which experience significant multiple-degree-of-freedom disturbances, a generalized motion compensation system using a “reference-point algorithm” is required that determines the length of a tow cable that should be reeled in or reeled out by an on-board winch system in response to external wave motion. This paper proposes, implements, and assesses four different reference-point algorithm approaches in both simulation and experimental environments. Of the proposed reference-point algorithms, the method that directly accounts for the tow cable angle proved to be most effective in both simulation and experimentation. It was found that there was little improvement between real-time measurements of the tow cable angle and a constant nominal tow cable angle—indicating a potential cost saving opportunity through the avoidance of real-time sheave-angle measurement.

A dog bite injury involving joints and bones has poor prognosis. We described a case of open proximal phalangeal fracture with bone defect of the left index finger due to dog bite injury. The patient was treated successfully with a pedicled second metacarpal vascularized bone graft based on the second dorsal metacarpal artery following debridement and external fixation. Subsequently, extensor tendon tenolysis wrapped with adipofascial flap based on the first dorsal metacarpal artery was performed. After obtaining supple joint of the finger, flexor tendon tenolysis was performed. The postoperative course was uneventful, without infection. Nineteen months after the last operation, there was slight pain in the finger at power grip, but no disability in activities of daily life and work. The total active motion of the left index finger was 245°, and plain radiography showed bony union without osteoarthritic change. Good clinical outcome was obtained through a combination of staged surgery. Level of evidence: Level V, therapeutic study.

Hand surgeons encountering pediatric patients should be attuned to both technical and practical facets of caring for congenital and traumatic pathologies. Psychosocial aspects include engaging children in conversation and factoring in both self and external perception of deformity. Medical considerations are also unique, from including child abuse in the differential to having techniques to assess active motion and sensation in the nonverbal child. Certain universal principles, such as minimizing radiation exposure and limiting needle sticks, have higher emphasis in pediatric patients than in adults. With these aspects in mind, treating children and their families can be a mutually rewarding experience.

This paper presents an active motion planning approach for a robotic manipulator operating in planetary surface exploration missions. A monocular camera is employed to examine the visually salient regions in an image, from which landforms of potential interests are extracted, and two key metrics are established to evaluate the information richness of the landforms. A next-best view manipulator motion planning is proposed, in which motions of the manipulator are actively planned to reach a better viewpoint to view the target landform, the safety of such operation is guaranteed by real-time estimating the relative distance using ORriented Brief (ORB)–simultaneous localization and mapping. The proposed active motion planning method is validated by an experimental trial, results from which demonstrate that it is able to safely acquire a better viewing of a just-detected planetary landform with full autonomy.

Purpose The aim of this work is to describe the clinical implementation of respiratory‐gated spot‐scanning proton therapy (SSPT) for the treatment of thoracic and abdominal moving targets. The experience of our institution is summarized, from initial acceptance and commissioning tests to the development of standard clinical operating procedures for simulation, motion assessment, motion mitigation, treatment planning, and gated SSPT treatment delivery. Materials and methods A custom respiratory gating interface incorporating the Real‐Time Position Management System (RPM, Varian Medical Systems, Inc., Palo Alto, CA, USA) was developed in‐house for our synchrotron‐based delivery system. To assess gating performance, a motion phantom and radiochromic films were used to compare gated vs nongated delivery. Site‐specific treatment planning protocols and conservative motion cutoffs were developed, allowing for free‐breathing (FB), breath‐holding (BH), or phase‐gating (Ph‐G). Room usage efficiency of BH and Ph‐G treatments was retrospectively evaluated using beam delivery data retrieved from our record and verify system and DICOM files from patient‐specific quality assurance (QA) procedures. Results More than 70 patients were treated using active motion management between the launch of our motion mitigation program in October 2015 and the end date of data collection of this study in January 2018. During acceptance procedures, we found that overall system latency is clinically‐suitable for Ph‐G. Regarding room usage efficiency, the average number of energy layers delivered per minute was

This retrospective study analyses the effect performing veins anastomoses before arteries anastomoses in digital replantation.38 adult patients with replantation of 12 thumbs and 39 fingers, in whom the veins anastomoses were performed prior to the arteries anastomoses, were compared with 29 patients with replantation of 9 thumbs and 30 fingers, in whom the arteries anastomoses were done first, with respect to the survival rate, total active motion, grip strength, and duration of the replantation.There was no significant difference between the two groups with respect to the survival rates, total active motion, and grip strength, while the duration of the replantation was significantly shorter in patients, in whom the veins anastomoses were performed prior to the arteries anastomoses (2 hours and 50 minutes versus 3 hours and 42 minutes; p 0.001).Performing veins anastomoses before arteries anastomoses in digital replantations reduces the replantation time significantly without influencing the survival rate and the clinical outcome.ZIEL: Diese Retrospektive Studie untersucht die Auswirkungen der Umkehrung der Sequenz der Mikroanastomosen mit Durchfuhrung der Venenanastomosen vor den Arterienanastomosen bei Finger- und Daumenreplantationen.38 erwachsene Patienten mit Replantation von 12 Daumen und 39 Fingern, bei denen die Venenanastomosen vor den Arterienanastomosen erfolgten, wurden bzgl. der Überlebensrate, der Grob- und Spitzgriffkraft, der Beweglichkeit und Dauer der Operation mit 29 Patienten mit Replantation von 9 Daumen und 30 Fingern verglichen, bei denen die Arterienanastomosen zuerst erfolgten.Während sich Überlebensrate, Grob- und Spitzgriffkraft sowie die Beweglichkeit der replantierten Finger und Daumen nicht signifikant unterschieden, war die Dauer der Operation bei Patienten, bei denen die Venenanastomosen zuerst durchgeführt wurden, signifikant kürzer als bei Patienten, bei denen die Arterienanastomosen zuerst erfolgten (2 h 50 min versus 3 h 42 min; p 0,001).Erfolgen bei Finger- und Daumenreplantationen die Venen- vor den Arterienanastomosen, verkürzt dies signifikant die Operationsdauer, ohne Auswirkung auf die Überlebensrate und das klinische Ergebnis zu haben.

Advances in fabrication methods have positioned Janus micromotors (JMs) as candidates for use as autonomous devices in applications across diverse fields, spanning drug delivery to environmental remediation. While the design of most micromotors is straightforward, the non-steady state active motion exhibited by these systems is complex and difficult to characterize. Traditionally, JM active motion is characterized using optical microscopy single particle tracking for systems confined in 2D. Dynamic light scattering (DLS) offers an alternative high-throughput method for characterizing the 3D active motion in bulk JM dispersions with additional capabilities to quantify time-dependent behavior for a broader range of JM sizes. Here, the active motion of spherical JMs is examined by DLS and it is demonstrated that the method enables decoupling of the translational and rotational diffusion. Systematic studies quantifying the time-dependent diffusive properties as a function of fuel concentration, JM concentration, and time after fuel addition are presented. The analyses presented in this work position DLS to facilitate future advances of JM systems by serving as a fast-screening characterization method for active motion.

Enabled by active motion of microrobots, conventional biological detection and chemical analyses limited by passive diffusion can be significantly enhanced with fast testing speed and unique sensitiveness. However, controlled release and precise enrichment of microrobot swarms are still difficult to accomplish and thus prohibit them away from practical applications. Here, an efficient and versatile strategy utilizing a needle-shaped hybrid sonoelectrode to disperse and aggregate distinct micromotors is presented, remarkably accelerating mass transfer and enhancing the signal intensity. Hydrogen bubbles generated at the tip of charged electrode can oscillate as actuated by the acoustic field, creating intensified vortexes to disperse micromotors spontaneously. Via removing the attached bubble, the sonoelectrode serving as solid needle isolator is capable of collecting micromotors in a large scale with acoustic streaming in the working reservoir at higher ultrasound frequency. Numerical calculation reveals the streaming profiles with/without microbubbles, and manipulations on classic spherical and tubular micromotor models confirm that the acoustic-powered prototype device is effective for controlling different swarming behaviors in microfluidic channels. Overall, the proposed hybrid sonoelectrode offers a universal and rapid strategy to tailor micromotor swarm behaviors, advancing intelligent microrobots to be featured with active enrichment and compatible for next-generation sensitive portable detection microsystems.

Background In this study, we evaluate the value of novel suture material based on monofilamentous-extruded polyfluoroethylene (PTFE) compared to polypropylene (PPL) and Fiberwire (FW). Materials and methods 60 flexor tendons were harvested from fresh cadaveric upper extremities. 4–0 sutures strands were used in the PPL, FW and PTFE group. Knotting properties and mechanical characteristics of the suture materials were evaluated. A 4-strand locked cruciate (Adelaide) or a 6-strand (M-Tang) suture technique was applied as core sutures for a tendon repair. Two-way ANOVA tests were performed with the Bonferroni correction. Results Stable knotting was achieved with 5 throws with the PPL material, 7 throws for FW and 9 throws for PTFE. In the PPL group, linear tensile strength was 45.92 ± 12.53 N, in the FW group 80.11 ± 18.34 N and in the PTFE group 76.16 ± 29.10 N. FW and PTFE are significantly stronger than PPL but show no significant difference among each other. Similar results were obtained in the subgroup comparisons for different repair techniques. The Adelaide and the M-Tang knotting technique showed no significant difference. Conclusion Fiberwire showed superior handling and knotting properties in comparison to PTFE. However, PTFE allows easier approximation of the stumps. In both, M-Tang and Adelaide repairs, PTFE was equal to FW in terms of repair strength. Both PTFE and FW provide for a robust tendon repair so that early active motion regimens for rehabilitation can be applied.

Numerous worm and arthropod species form physically-connected aggregations in which interactions among individuals give rise to emergent macroscale dynamics and functionalities that enhance collective survival. In particular, some aquatic worms such as the California blackworm (Lumbriculus variegatus) entangle their bodies into dense blobs to shield themselves against external stressors and preserve moisture in dry conditions. Motivated by recent experiments revealing emergent locomotion in blackworm blobs, we investigate the collective worm dynamics by modeling each worm as a self-propelled Brownian polymer. Though our model is two-dimensional, compared to real three-dimensional worm blobs, we demonstrate how a simulated blob can collectively traverse temperature gradients via the coupling between the active motion and the environment. By performing a systematic parameter sweep over the strength of attractive forces between worms, and the magnitude of their directed self-propulsion, we obtain a rich phase diagram which reveals that effective collective locomotion emerges as a result of finely balancing a tradeoff between these two parameters. Our model brings the physics of active filaments into a new meso- and macroscale context and invites further theoretical investigation into the collective behavior of long, slender, semi-flexible organisms.

Numerous worm and arthropod species form physically-connected aggregations in which interactions among individuals give rise to emergent macroscale dynamics and functionalities that enhance collective survival. In particular, some aquatic worms such as the California blackworm (Lumbriculus variegatus) entangle their bodies into dense blobs to shield themselves against external stressors and preserve moisture in dry conditions. Motivated by recent experiments revealing emergent locomotion in blackworm blobs, we investigate the collective worm dynamics by modeling each worm as a self-propelled Brownian polymer. Though our model is two-dimensional, compared to real three-dimensional worm blobs, we demonstrate how a simulated blob can collectively traverse temperature gradients via the coupling between the active motion and the environment. By performing a systematic parameter sweep over the strength of attractive forces between worms, and the magnitude of their directed self-propulsion, we obtain a rich phase diagram which reveals that effective collective locomotion emerges as a result of finely balancing a tradeoff between these two parameters. Our model brings the physics of active filaments into a new meso- and macroscale context and invites further theoretical investigation into the collective behavior of long, slender, semi-flexible organisms.

We report the outcomes of delayed primary repair of flexor tendons in Zone 2 in 31 fingers and thumb (28 patients) averaging 15 days (range 4–37) after injury in 2020. The delay was longer than usual due to the COVID-19 pandemic. The tendons were repaired with a 6-strand core suture (M-Tang method) or a double Tsuge suture and a peripheral suture. This was followed by an early, partial-range, active flexion exercise programme. Adhesions in four digits required tenolysis. These patients were not with longest delay. Outcomes of two improved after tenolysis. The other two patients declined further surgery. One finger flexor tendon ruptured in early active motion. This was re-repaired, and final outcome was good. Overall excellent and good results using the Tang criteria were in 27 out of 31 fingers and thumbs (87%). The time elapsed between the injury and surgery is not an important risk factor for a good outcome, rather it depends on proper surgical methods, the surgeon's experience and early mobilization, properly applied. Adhesions may occur, but they can be managed with tenolysis. Level of evidence: IV

In this thesis we describe several colloidal model systems. We first study the lattice structures in monolayers of colloidal superballs prepared using the unidirectional rubbing method. In this method, the ordering of the colloidal superballs is achieved by mechanically rubbing them onto a polydimethylsiloxane- (PDMS) coated surface. We show using both small-angle X-ray scattering (SAXS) and scanning electron microscopy (SEM) that a transition in the lattice structures result from a well-defined hexagonal lattice for spherical superballs to the sliding phase for more cube-like superballs. In these lattice structures the cube-like superballs form chains in the direction in which the mechanical rubbing was applied which are able to slide freely with respect to each other. Furthermore, we show that active colloids with an asymmetrically sputter coated metal patch display circling motion under the influence of an alternating electric field. Their velocity and angular velocity can be tuned in situ by varying the magnitude and frequency of the alternating electric field. Finally, we present a method to prepare active anisotropic hydrogel particle. Using this simple and accesible method, particles with an arbitrary geometry and tunable thickness can be prepared which display an active motion under the influence of an alternating electric field.

Introduction The purpose of this study was to evaluate the long-term outcome of an extended range of hand fractures treated with titanium, low profile plates, and screws. Materials and methods This retrospective study included adult patients with at least one phalangeal and/or metacarpal fracture, treated with mini titanium plates and screws, between 2004-2016, in a single trauma center, that were followed-up for at least 24 months and with complete, intact medical records. Results 90 patients (79 men and 11 women) with 114 hand (46 phalangeal, 68 metacarpal) fractures fulfilled the inclusion criteria. Thirty-two fractures were open (28.07%), 27 were intra-articular (23.68%), and 12 were both open and intra-articular fractures. The mean age of the patients was 36.02 years (range 17-75). Mean follow-up was 95.3 months (range 24 to 138). Open fractures had a reduced mean grip strength and total active motion. No difference was observed between intra-articular and extra-articular fractures (for grip strength and total active motion). Predictors of the final outcome included the severity of the initial injury (open vs closed) and not the anatomic location (intra- or extra-articular, metacarpal, or phalangeal) of the fracture. Conclusions Low-profile plates and screws can successfully be used to establish union and restore the alignment of the fractured bone while achieving a satisfactory clinical outcome, even in cases of open or intra-articular fractures.

Background Although there is consensus that closed tendinous mallet finger injuries should be treated conservatively, the best method of immobilization to be used is not clear and the existing data in the literature are not conclusive. The aim of this study is to compare the results of four different immobilization methods used in the conservative treatment of tendinous mallet finger injury. Methods Ninety-six patients with tendinous mallet finger injury were treated with four different immobilization methods (stack orthosis, thermoplastic orthosis, aluminum orthosis, and Kirschner wire [K-wire] immobilization). The patients then were assessed with distal interphalangeal joint extensor lag, total active motion (TAM), grip strength, and Abouna and Brown Criteria. Results No significant difference was found between four immobilization methods in extensor lag and TAM at the 8th and 12th weeks. According to grip strength assessment, stack orthosis group was found to have significantly better results than the K-wire and aluminum orthosis groups at 12 weeks, while the difference was not significant versus the thermoplastic orthosis group. Conclusion In this first study making multiple comparisons between four immobilization methods used in the treatment of tendinous mallet finger injury, the only significant difference detected between the groups was the superior grip strength with stack orthosis compared with K-wire immobilization and aluminum orthosis.

Background: Persistent postural-perceptual dizziness (PPPD) is a persistent chronic vestibular syndrome exacerbated by upright posture/walking, active or passive motion, and exposure to moving or complex visual stimuli. PPPD has four precursors: phobic postural vertigo, space-motion discomfort, visual vertigo, and chronic subjective dizziness. These four diseases share clinical features that form the basis of the diagnostic criteria for PPPD. Semiological similarities do not necessarily mean that PPPD is a single entity. However, if PPPD is not a single disorder but just a composite of four precursors, it may be subdivided according to the characteristics of each precursor.Objective: To test whether PPPD is a single disorder, we attempted a subtyping of PPPD.Methods: One-hundred-eight untreated patients with PPPD were enrolled in the study, who filled out the Niigata PPPD Questionnaire (NPQ) that consists of 12 questions on exacerbating factors for PPPD. A factor analysis of the patients' answers to the NPQ and a subsequent cluster analysis of the patients with PPPD using factors revealed by the factor analysis were performed. To validate our cluster classification, cluster differences were assessed using analysis of variance. Multiple comparison analyses were performed on demographical data, precipitating diseases, the Dizziness Handicap Inventory, the Hospital Anxiety and Depression Scale, and several vestibular tests to characterize each cluster.Results: Factor analysis revealed three underlying factors among the exacerbating factors in the NPQ. Exacerbation by visual stimuli (visual factor) accounted for 47.4% of total variance in the questionnaire. Exacerbation by walking/active motion (active-motion factor) and by passive motion/standing (passive-motion/standing factor) accounted for 12.0 and 7.67% of variance, respectively. Cluster analysis revealed three clusters: the visual-dominant subtype (n = 49); the active motion-dominant subtype (n = 20); and the mixed subtype (n = 39). The patients in the active motion-dominant subtype were significantly older than those in the visual-dominant subtype. There were no significant differences among the subtypes in other demographical data or conventional vestibular tests.Conclusions: The most common main exacerbating factor of PPPD was the visual factor. PPPD may be categorized into three subtypes. Conventional vestibular tests failed to point the characteristics of each subtype.

The basic requirement of rehabilitation training is active participation. This paper introduces our braincomputer interface based robot gives spinal cord injury (SCI) patients a full-cycle active rehabilitation for the first time. For patients with muscle strength level 0, we use brain-computer interface to recognize active motion intention of brain, which control the running speed of robot. For patients with muscle strength greater than level 0, we combine brain-computer interface and torque sensor to realize assistance and resistance training with the active participation of the brain. Integrated brain-computer interface control and force control, we achieved the active participation of patients from muscle strength 0 to muscle strength 4 throughout the rehabilitation cycle. Two typical SCI patients took part in the training, with an average of more than three-quarters of their 20-minute rehabilitation sessions active. After 2 weeks training, both patients had positive rehabilitation effects.

The active motion of phoretic colloids leads them to accumulate at boundaries and interfaces. Such an excess accumulation, with respect to their passive counterparts, makes the dynamics of phoretic colloids particularly sensitive to the presence of boundaries and pave new routes to externally control their single particle as well as collective behavior. Here we review some recent theoretical results about the dynamics of phoretic colloids close to and adsorbed at fluid interfaces in particular highlighting similarities and differences with respect to solid-fluid interfaces.

We study the stochastic dynamics of a particle with two distinct motility states. Each one is characterized by two parameters: one represents the average speed and the other represents the persistence quantifying the tendency to maintain the current direction of motion. We consider a run-and-tumble process, which is a combination of an active fast motility mode (persistent motion) and a passive slow mode (diffusion). Assuming stochastic transitions between the two motility states, we derive an analytical expression for the time evolution of the mean square displacement. The interplay of the key parameters and the initial conditions as for instance the probability of initially starting in the run or tumble state leads to a variety of transient regimes of anomalous transport on different time scales before approaching the asymptotic diffusive dynamics. We estimate the crossover time to the long-term diffusive regime and prove that the asymptotic diffusion constant is independent of initially starting in the run or tumble state., Comment: 9 pages, 6 figures

Background: Several approaches to plate fixation of the proximal phalanx have been proposed, such as the dorsal extensor splitting approach and the lateral or dorso-lateral extensor sparing approach, which aims to minimise invasiveness to promote native extensor tendon glide. This study aimed to meta-analyse the outcomes of these two approaches. Methods: A systematic review of electronic databases was undertaken, and the outcomes of comparative studies meta-analysed. Results: Three studies were included for meta-analysis. Total active motion (TAM) was significantly greater in the extensor sparing group compared to the extensor splitting (Mean difference 8.52 degrees, 95%CI 0.8–16.36, p = 0.03). Conclusions: This study demonstrates that there is preliminary evidence favouring the use of extensor sparing approaches when fixing proximal phalanxes – however, this result requires validation with randomised controlled trials.

Objectives/Interrogation: Several surgical methods have been performed for the correction of swan-neck deformity. We introduce a novel surgical method for swan-neck deformity caused by volar plate injury of the proximal interphalangeal (PIP) joint. Methods: A 61-year-old woman presented with[for full text, please go to the a.m. URL], 14th Triennial Congress of the International Federation of Societies for Surgery of the Hand (IFSSH), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT), 11th Triennial Congress of the International Federation of Societies for Hand Therapy (IFSHT)

Summary. Recently, better outcomes have been reported when up-to-date developments in flexor tendon surgery and therapy were followed. Slightly tensioned multistrand repairs, judicious venting of pulleys, and early active motion are widely accepted principles. In addition to these principles, tailoring of the repair according to intraoperative active movement with wide awake local anesthesia no tourniquet (WALANT) surgical setting is recommended for better results. We aimed to describe our up-to-date approach to flexor tendon surgery and therapy with the help of visual communication tools of this age. The ideal primary repair of flexor tendons, the management of delayed presentation flexor tendon injuries, the key steps to achieve better results with flexor tendon therapy, and the tele-rehabilitation experience during COVID-19 pandemic will be highlighted. Zone 2 flexor tendon injuries are the most demanding part and will be focused on.

Proximal phalangeal fractures have traditionally been fixed via either Kirschner wires or dorsal plating. Concerns regarding lack of compression and potential for infection with wire fixation, and adhesion formation and stiffness with plating, have lead to alternative fixation methods, such as intramedullary screw fixation. However, the literature regarding this modality is limited. Methods: A systematic review was performed to review the literature regarding intramedullary screw fixation for proximal phalangeal fractures. English language studies that reported original data and commented on at least one postoperative measure of function were eligible for inclusion. 4 studies were eligible for inclusion, with a further 3 studies assessing proximal and middle phalanges analysed separately. Total active motion was greater than 240° in all proximal phalangeal studies; mean post-operative DASH was 3.62. 6% of patients sustained a major complication. Intramedullary screw fixation of proximal phalangeal fractures is safe, providing stable fixation to allow early motion.

Introduction Flexor tendon lacerations in zone II have been reported to be the most complicated of all tendon injuries. Currently, there is no consensus on treatment in surgical management for patients with flexor tendon laceration of flexor digitorum profundus and flexor digitorum superficialis (FDS). The aim of this study was to evaluate whether the repair of FDS tendons provided superior functional outcomes compared with FDS excision in Hispanic patients. Methods Total active motion, original Strickland criteria, and the disability of arm shoulder and hand questionnaire were provided postoperatively at 3 and 6 months to all consecutive Hispanic patients who underwent zone II flexor tendon repair. The cohort was divided into two groups, those who underwent FDS repair and those underwent FDS excision. Results Functional and disability outcome analysis showed a notable improvement with FDS repair using total active motion, Strickland criteria, and disability of arm shoulder and hand score at the 3 months postoperative interval. No statistical differences were identified regarding functional and disability outcomes at the 6-month evaluation between both groups. Conclusions Among Hispanics, the FDS-repaired group had similar functional and disability outcomes at their 6 months postoperative evaluation compared with the FDS-excised group. Increased awareness for tendon rerupture during the initial 3 months of index surgery is recommended for FDS-excised patients.

This paper describes how collections of small synthetic chemically-powered motors function in complex filament networks. Like biological molecular machines, these synthetic motors derive their chemical fuel from nonequilibrium reactions in their environment, attach to filaments and move along them but, unlike biological machines, they use self-generated chemical gradients to effect propulsion. The structure of the filament network strongly influences the character of the collective motions of these motors.

Introduction Management of unstable fractures of the proximal phalanx is a challenge. Objective The purpose of this study is to introduce to the literature the use of “bi-cortical” periarticular K-wire fixation for displaced unstable transverse extra-articular fractures of the base of the proximal phalanx of the fingers. Patients and Methods This is a retrospective study of 30 patients with such fractures treated by the author over the last 10 years. Demographic data were collected and surgical complications were documented. The outcome was considered excellent, good, fair and poor if the total active motion of the finger was >260o, 250o-259o, 210o - 249o, and Results The worst outcome was seen in an elderly patient who sustained multiple fractures and concurrent flexor tendon injury. The remaining 29 patients were relatively young (mean age of 29 years, range = 19 – 42 years) and sustained an isolated single fracture from a fall or a fight. Out of these 29 patients, the outcome was excellent in 27 patients and good in the remaining 2 patients. Conclusions The “bi-cortical” periarticular k-wire fixation is best suited for transverse extra-articular fractures of the base of the proximal phalanx. The wire avoids all joints and hence, early post-operative mobilization is feasible. The technique is simple and obtains a favorable outcome in most patients. Type of study/level of evidence Therapeutic IV

It is now well established that microswimmers can be sorted or segregated fabricating suitable microfluidic devices or using external fields. A natural question is how these techniques can be employed for dividing swimmers of different motility. In this paper, using numerical simulations in the dilute limit, we investigate how motility parameters (time of persistence and velocity) impact the narrow-escape time of active particles from circular domains. We show that the escape time undergoes a crossover between two asymptotic regimes. The control parameters of the crossover is the ratio between the persistence length of the active motion and the typical length scale of the circular domain. We explore the possibility of taking advantage of this finding for sorting active particles by motility parameters.

Upright infant active cervical motion (ACM) is difficult to measure accurately by a single examiner. Clinically, physical therapists use visual estimation, which has limited reliability and concurrent validity with gold standards. Consistent, reliable, and valid active motion measurements are needed to document infant status and response to intervention.Two-dimensional (2D) photo digitization measurements were compared to three-dimensional (3D) motion analysis measures of infant active neck rotation and lateral flexion.Typically-developing infants participated (five boys, nine girls; 3-7.5 months). An experienced pediatric physical therapist and six novice raters marked photographs and used two different 2D methods to measure cervical rotation and three different 2D methods to measure cervical lateral flexion in photographs. To determine the intra- and interrater reliability of the 2D measurement methods and their concurrent validity with the 3D measures, a subset of lateral flexion photos was marked and measured by 14 experienced pediatric physical therapists.Novice and experienced examiner measurements of 2D ACM exhibited moderate to excellent intra- and inter-rater reliability. The results of the 2D lateral flexion ACM measurements completed by novice and experienced raters consistently differed from those obtained using the 3D measurement methods.The 2D rotation ACM measurement methods were reliable and demonstrated concurrent validity with the gold standard 3D measure. Infants' lateral flexion ACM examined using 2D measures did not correlate with the results of 3D measurements. This indicated that 2D measurements of active infant cervical lateral flexion could not be used as a valid indicators of 3D motion.

Nonspherical self-propelling colloidal particles offer many possibilities for creating a variety of active motions. In this work, we report on the transition from linear to circular motion of active spherical-cap particles near a substrate. Self-propulsion is induced by self-diffusiophoresis by catalytic decomposition of hydrogen peroxide (H2O2) on one side of the particle. Asymmetric distribution of reaction products combined with the asymmetric shape of the particle gives rise to two types of motions depending upon the relative orientation of the particle with respect to the underlying substrate. At a low concentration of H2O2, linear active motion is observed, whereas increasing the H2O2 concentration leads to persistent circular motion. However, the speed of self-propulsion is nearly independent of the size of the particle. The study demonstrates the use of nonspherical particles to create linear and circular motion by varying the fuel concentration.

We report the outcomes of zone 2 tendon repairs in 60 fingers using a strong core suture, sparse peripheral stitches and early active motion. From January 2014 to April 2016, we repaired 60 flexor digitorum profundus tendons with a tensioned 4-strand or 6-strand core suture and three to four peripheral stitches. The A2 or A4 pulleys were vented as necessary. Following early active flexion of the repaired tendons, no repairs ruptured and 52/60 (87%) fingers recovered to good or excellent function using the Tang criteria after follow-up of 8–33 months. We conclude that tensioned multi-strand strong core repairs only require sparse peripheral stitches and are safe for early active flexion. Standard peripheral sutures are not necessary. The core sutures should be properly tensioned to prevent gapping at tendon repair site and pulleys should be sufficiently vented to allow tendon motion. Level of evidence: IV

We investigate the aggregation and phase separation of thin, living T. tubifex worms that behave as active polymers. Randomly dispersed active worms spontaneously aggregate to form compact, highly entangled blobs, a process similar to polymer phase separation, and for which we observe power-law growth kinetics. We find that the phase separation of active polymerlike worms does not occur through Ostwald ripening, but through active motion and coalescence of the phase domains. Interestingly, the growth mechanism differs from conventional growth by droplet coalescence: the diffusion constant characterizing the random motion of a worm blob is independent of its size, a phenomenon that can be explained from the fact that the active random motion arises from the worms at the surface of the blob. This leads to a fundamentally different phase-separation mechanism that may be unique to active polymers., Comment: 4 pages, 4 figures

There is a consensus that after a flexor tendon repair an aggressive rehabilitation protocol with early active motion can improve functional outcome, provided that the combination of material and suturing technique can meet the higher biomechanic demands. Bearing this in mind we evaluated a polytetrafluoroethylene (PTFE) suture (SERAMON®, Serag-Wiessner) as a possible material for flexor tendon repair. 40 flexor tendons were harvested from fresh cadaveric upper extremities. 3–0 and 5–0 strands were used both in the polypropylene (PPL) as well as in the PTFE group. In the first phase of the study, we evaluated knotting properties and mechanical characteristics of the suture materials themselves. In the second phase, a 2-strand Kirchmayr–Kessler suture technique was applied for a core suture of a flexor tendon (n = 16). In the third phase, we performed a tendon repair including an epitendinous running suture with 5–0 PPL or 5–0 PTFE material (n = 22). One way ANOVA tests were performed. The linear loading strength of single strand knotted PPL 3–0 was 19.87 ± 0.59 N. The linear loading strength of knotted PTFE 3–0 was 32.47 ± 1.67 N. For PPL 3–0 maximum linear strength was achieved with five knots, for PTFE 3–0 with eight knots. When a Kirchmayr–Kessler core-only repair was performed, then in the PPL group the loading strength of the repaired tendon was 30.74 ± 9.77 N. In the PTFE group the loading strength was 23.74 ± 5.6 N (p = 0.10). However, all repairs in the PTFE group failed due to cheese wiring. When a Kirchmayr–Kessler core and epitendinous repair technique was used, then in the PPL group the loading strength of the repaired tendon was 49.90 ± 16.05 N. In the PTFE group the loading strength was 73.41 ± 19.81 N (p = 0.006). PTFE demonstrates superior strength properties in comparison to PPL for flexor tendon repairs. However, standard 2 strand techniques have proved inadequate to bear the higher biomechanic demands.

Profound improvements in function have been described in patients following reverse total shoulder arthroplasty (RSA). Previous studies have demonstrated young age, high preoperative function, and neurologic dysfunction to be predictors of poor functional improvement. However, no study to date has focused on patients electing to undergo RSA for function more than pain. The purpose of this study was to compare the outcomes of RSA in patients with minimal preoperative pain with those in patients who have higher baseline pain.We performed a retrospective matched-cohort study of RSA patients treated by a single surgeon with a minimum of 2 years' follow-up. Patients with at least moderate baseline pain (function-pain group), predefined by existing literature as a visual analog scale pain score3, were matched 3:1 based on sex, indication, and age to patients with minimal pain (function group), defined as a visual analog scale score ≤ 3. Patient-reported outcome measures, active range of motion, and overall satisfaction were compared. The percentage of maximal improvement in outcomes and the proportion of patients exceeding the established threshold that predicts excellent satisfaction were also compared.A total of 260 patients (195 in function-pain group and 65 in function group) were selected for matched analysis with a similar sex distribution; the mean age was 73.1 years, and the mean follow-up period was 50 months. No differences in most recent postoperative function, overall improvement in functional scores, and active motion were found between patients in the 2 groups (P.05). However, pain scores improved only in patients with at least moderate baseline pain (P.0001). Patient satisfaction was significantly different (P = .035), as 10.8% of patients who elected to undergo RSA for function were unsatisfied. The function cohort also had worse percentage of maximal Simple Shoulder Test score (P = .034) and American Shoulder and Elbow Surgeons score (P.0001) improvement, and a lower proportion of these patients exceeded the threshold for the percentage of maximal improvement that predicts an "excellent" outcome (P.0001).RSA patients with minimal preoperative pain achieve significant improvements in function and motion similar to those who choose to undergo RSA for both pain and function, but they are less satisfied and are less likely to achieve an excellent outcome. Patients electing to proceed with RSA with minimal pain should be counseled accordingly.

The objective of this study was to clarify the difference in thumb deformity between our case with ring chromosome 4 and thumb polydactyly, in which ulnar side was small and had no active motion, and other cases of ring chromosome 4, by analyzing previous reports. Our case had bilateral atypical thumb polydactyly, which was classified as type 4 on the right side and type 5 on the left side, according to the Japanese Society for Surgery of the Hand: Modified International Federation of Societies for Surgery of the Hand classification. Of the 39 cases in previous reports, 20 (51.3%) had thumb deformities. Among them, 19 cases (95%) showed radial ray deficiency and only 1 case (5%) showed bilateral thumb polydactyly. Clinodactyly was seen in 5 cases (12.8%). Foot deformities were present in 6 cases (15.4%). We discussed about thumb polydactyly with and without chromosomal deformities.

The propulsion of platinum-coated polystyrene prolate ellipsoids, as generated by catalytic decomposition of hydrogen peroxide, is characterized by direct visualization of the trajectories of the active particles. These Janus ellipsoids were fabricated by stretching micron-sized polystyrene spheres into different aspect ratios; half of the particle is then capped lengthwise along the ellipsoid's major axis, with platinum deposition. These particles exhibit complex dynamical trajectories in aqueous solutions of hydrogen peroxide of concentration in the range of 2-8% (w/v). In this range, a transition from three-dimensional passive Brownian motion to two-dimensional active motion is observed as the hydrogen peroxide concentration is increased. This transition from passive to active motion is complete by 4% (w/v) hydrogen peroxide. We quantify the effect of particle aspect ratio on the mean-squared displacement and mean-squared angular displacement at the highest hydrogen peroxide concentration. The two-dimensional trajectories of the individual particles were grouped into three categories for dynamical analysis. In the first category, ballistic ellipsoids translate at least 5 times more than purely diffusive ellipsoids at the characteristic time scale of rotational diffusion. In the second category, spinning ellipsoids move only short distances with a dominant rotation about the minor axis; this rotation persists for many revolutions. A third category captures trajectories that include both significant translation and rotation. We consider the physical origins of the observed categories of motion and extract the forces and torques generated by the catalytically generated propulsion as a function of aspect ratio. The particle velocity, and therefore the active force, increases with the aspect ratio.

Microorganisms use chemotaxis, regulated by internal complex chemical pathways, to swim along chemical gradients to find better living conditions. Artificial microswimmers can mimic such a strategy by a pure physical process called diffusiophoresis, where they drift and orient along the gradient in a chemical density field. Similarly, for other forms of taxis in nature such as photo- or thermotaxis the phoretic counterpart exists. In this Account, we concentrate on the chemotaxis of self-phoretic active colloids. They are driven by self-electro- and diffusiophoresis at the particle surface and thereby acquire a swimming speed. During this process, they also produce nonuniform chemical fields in their surroundings through which they interact with other colloids by translational and rotational diffusiophoresis. In combination with active motion, this gives rise to effective phoretic attraction and repulsion and thereby to diverse emergent collective behavior. A particular appealing example is dynamic clustering in dilute suspensions first reported by a group from Lyon. A subtle balance of attraction and repulsion causes very dynamic clusters, which form and resolve again. This is in stark contrast to the relatively static clusters of motility-induced phase separation at larger densities. To treat chemotaxis in active colloids confined to a plane, we formulate two Langevin equations for position and orientation, which include translational and rotational diffusiophoretic drift velocities. The colloids are chemical sinks and develop their long-range chemical profiles instantaneously. For dense packings, we include screening of the chemical fields. We present a state diagram in the two diffusiophoretic parameters governing translational, as well as rotational, drift and, thereby, explore the full range of phoretic attraction and repulsion. The identified states range from a gaslike phase over dynamic clustering states 1 and 2, which we distinguish through their cluster size distributions, to different types of collapsed states. The latter include a full chemotactic collapse for translational phoretic attraction. Turning it into an effective repulsion, with increasing strength first the collapsed cluster starts to fluctuate at the rim, then oscillates, and ultimately becomes a static collapsed cloud. We also present a state diagram without screening. Finally, we summarize how the famous Keller-Segel model derives from our Langevin equations through a multipole expansion of the full one-particle distribution function in position and orientation. The Keller-Segel model gives a continuum equation for treating chemotaxis of microorganisms on the level of their spatial density. Our theory is extensible to mixtures of active and passive particles and allows to include a dipolar correction to the chemical field resulting from the dipolar symmetry of Janus colloids.

© 2018 American Chemical Society. The quest to provide clean water to the entire population has led to a tremendous boost in the development of environmental nanotechnology. Toward this end, micro/nanomotors are emerging as attractive tools to improve the removal of various pollutants. The micro/nanomotors either are designed with functional materials in their structure or are modified to target pollutants. The active motion of these motors improves the mixing and mass transfer, greatly enhancing the rate of various remediation processes. Their motion can also be used as an indicator of the presence of a pollutant for sensing purposes. In this Perspective, we discuss different chemical aspects of micromotors mediated environmental cleanup and sensing strategies along with their scalability, reuse, and cost associated challenges.

Background: Unstable metacarpal and phalangeal fracturesrepresent more than one third fractures of the hand. The severethe trauma, the more grave the fracture that herald perfectmanagement is needed.Objective: Assessment of the clinical and radiologicaloutcomes of metacarpal and proximal phalangeal fractures inpatients who underwent open anatomic reduction and fixationwith plate and screws or by intramedullary K wire fixation.Patients and Methods: Twenty five patients with unstablemetacarpal and phalangeal fractures were treated; in group I12 male patients operated by plate and screw fixation andgroup II 13 male patients operated by intramedullary K wirefixation. For the two groups total active motion "TAM, DASHscore, postoperative lateral angulation, loss of reduction andradiological healing were assessed.Results: There was a non-significant difference betweengroup I (Plate and screw fixation) and group II (Intramedullarynail fixation) as regard the follow-up period or associationbetween loss of reduction and removal of hard ware (p>0.05).Group I showed a significant increase in the mean values ofsurgery duration and TAM (p

Proximal interphalangeal joint (PIPJ) flexion contracture is a challenging and often frustrating problem. Treatment of PIPJ contracture begins with conservative measures. With good compliance and prolonged use, favorable results can be achieved using these modalities. For contractures that fail to respond to conservative treatment, surgical intervention can be considered. The affected structures that can be released during surgery include the accessory collateral ligaments, volar plate, checkrein ligaments, retinacular ligaments, and the flexor and extensor tendons. A stepwise approach to release is typically favored in which active motion is tested after each release to determine the need for subsequent releases.

Background An understanding of the substantial clinical benefit (SCB) after total shoulder arthroplasty (TSA) may help to gauge a minimum threshold beyond which a patient perceives his or her outcome as being substantially better. This study quantifies SCB for 7 outcome metrics and active motion measurements after shoulder arthroplasty and determines how these values vary based on prosthesis type, patient age at surgery, sex, and length of follow-up. Methods A total of 1,568 shoulder arthroplasties with 2-year minimum follow-up were performed by 13 shoulder surgeons and enrolled in a multicenter registry. The SCB for the American Shoulder and Elbow Surgeons Shoulder Assessment, Constant Score, University of California Los Angeles Shoulder Rating Scale, Simple Shoulder Test, Shoulder Pain and Disability Index, global shoulder function, and visual analog scale pain scores, as well as active abduction, flexion, and external rotation were calculated for different patient cohorts using an anchor-based method. Results The anchor-based SCB results were American Shoulder and Elbow Surgeons score, 31.5 ± 2.0; Constant Score, 19.1 ± 1.7; University of California Los Angeles Shoulder Rating Scale score, 12.6 ± 0.5; Simple Shoulder Test score, 3.4 ± 0.3; Shoulder Pain and Disability Index score, 45.4 ± 2.2; global shoulder function, 3.1 ± 0.2; visual analog scale, 3.2 ± 0.3; active abduction, 28.5° ± 3.1°; active forward flexion, 35.4° ± 3.5°; and active external rotation, 11.7° ± 1.9°. Anatomic TSA patients, male patients, and patients of longer follow-up duration were associated with higher SCB values than female patients, reverse TSA patients, and patients of shorter follow-up duration. Conclusion Our analysis demonstrated two-thirds of patients achieved the SCB threshold after TSA. Generally, a change of 30% of the total possible score for each outcome metric approximates or exceeds this SCB threshold.