Pedis Research Articles

Анализ результатов лечения пациентов с деформациями стоп при подагре

Анализ результатов лечения пациентов с деформациями стоп при подагре

Orthopedic Lower Limb Deformities in Cerebral Palsy

Introduction: One-third of children with cerebral palsy (CP) do not yet walk at the age of 5. Orthopedic deformity is one of the pathologies that may compromise the efficiency of gait in those patients. The aim of our study was to describe the clinical characteristics of orthopedic deformities for CP patients and to describe device prescription to manage the deformities. Methods: A retrospective chart review was conducted at the Equipment Teaching Hospital of Madagascar, after ethic committee approval, during a period of 1 year, from the beginning of January 2017 to the end of December 2017. Patients diagnosed with CP, during the period of the study, regardless of age and gender, were included in the study. Incomplete patients' records have been excluded from the study. The different types of orthopedic deformities were analyzed. Results: New cases of CP were in the order of 5.61% (n = 100) in 1783 new patients seen in consultation during 2017. Ninety-five patients were kept out. Eighty-nine percent of patients reported to the hospital after 12 months of age. Orthopedic deformity was detected in 48 patients, including 27.36% with deformity of the foot, 5.26% of the knee, 4.21% of the hip, and 16.84% of the spine. More than 73% of the patients had spasticity. In 45.26% of the cases, patients with CP had a complete functional restriction with a Gross Motor Function Classification System V (GMFCS), and only 27 patients had GMFCS I or II. In 82.1% of the cases, patients with CP needed devices to reduce their deficit or maintain functional gain. Conclusion: CP is a public health problem. Orthopedic deformities are often discovered late, affecting the gait quality for these patients. Orthopedic deformities prevention is crucial, and multidisciplinary care should be done early.

Designing and evaluation of new dynamic prosthetic foot on transtibial amputees in a low resource setup

BACKGROUND: Foot as an essential part in lower extremity, serves for variety of purposes in daily life. Complex anatomy and biomechanics of normal foot makes its prosthetic replacement quite challenging. Technological boom in prosthetic industries has somehow improved the performance of prosthetic foot but also hike the cost, resulting in limited accessibility to majority of prosthetic user. In this study, we have designed a new dynamic prosthetic foot at low cost and compare its efficacy from the traditional solid-ankle, cushion-heel (SACH) foot.MATERIALS AND METHODS: The current prototype presented is a dynamic foot design consisting of commercially available thermoplastic materials that resembles a hybrid model with true ankle articulation and a flexible keel in order to mimic motion in all cardinal planes. A posttest experimental study has been conducted with fifteen individuals selected purposively. The gait parameters with current prototype and SACH foot were analyzed in conventional way by using 10 meter walk test and energy cost was estimated by calculating physiological cost index (PCI). The correlation between gait variables and PCI were analyzed through a paired t-test.RESULTS: Data analysis shows significant differences in the gait characteristics as stride length (P = 0.000), cadence (P = 0.001), velocity (P = 0.000), and PCI (P value 0.001), comparing the SACH foot and current foot prototype.CONCLUSION: The study outcome reveals the advantage of current prototype over conventional SACH foot in terms of gait characteristic and energy cost at self-selected walking speed.

ПРОТОТИП ТРАНСФЕМОРАЛЬНОГО ПРОТЕЗА С АКТИВНЫМ ИСКУССТВЕННЫМ КОЛЕННЫМ СУСТАВОМ

This article presents a transfemoral prosthesis prototype with active control of an artificial knee joint. One of the main criteria used in the design of the prosthesis was to achieve the maximum biological similarity of this device in order to provide optimal conditions conducive to user natural walking. The artificial knee joint, designed on the basis of a polycentric higed mechanism with intersecting links, provides such conditions at the design level, and a three-level hierarchical control system, built on the basis of an intelligent-synergetic concept, at the control level. To recognize user's intentions, the intelligent subsystem uses algorithms for comparing graphic images of user's walking phases by the method of estimating the invariant moments of Hu. After that, prosthesis elements movements are planned in the synergistic subsystem in accordance with the synergistic quality criteria. The algorithms used in the control system are adjusted depending on what type of artificial foot is used in the prosthesis: active, semi-active or passive (purely mechanical). Mathematical modeling of the prosthesis operation shows that the nature of its functioning corresponds to the quality criteria adopted in the design.

Clasificador de huellas plantares mediante imagen digital

Flat foot and cavus foot are two types of foot that can cause health problems at an advanced age. These types of foot may change because they evolve with age. Due to this, it is possible to correct the flat and cavus foot. Footprints can be used in order to detect these types of foot. This paper presents the development of a digital podoscope which, with the help of software, can generate a prognosis classification (cavus, normal or flat). The podoscope consisted of a glass supported by a metal frame with a camera at the bottom and lighting on the sides. The software consisted of a user interface developed with Visual Studio and image processing with MATLAB. The feet of 51 children of age range between 6 and 12 years were classified in an approximate time of 1 hour and a half over four days. The estimated time of each standing classification was approximately 1.5 minutes.

Centrifuge modelling of uplift response of suction caisson groups in soft clay

This paper describes a program of centrifuge model tests on the uplift behaviour of suction caisson foundations. The parameters considered were the loading rate, caisson diameter (D), soil strength profile, and type of footing (i.e., mono-caisson and tetra-caissons group). The loading responses were examined in terms of total uplift resistance, suction beneath the caisson lid, and the vertical displacements of the caisson and at the soil surface. There exists a critical uplift displacement, approximately 0.02D and 0.01D for the mono-caisson and the tetra-caissons groups, respectively, at which a turning point can be identified in the load–displacement curve. This was found to be attributed to the adhesion on the caisson–soil interface reaching a peak response and then dropping. Of interest is that the tetra-caissons group exhibits much greater normalized uplift resistance than the mono-caisson group before reaching an uplift displacement of about 0.02D, suggesting superiority of the former in term of serviceability. However, a reversed trend was observed at greater displacement, and accordingly an empirical model was derived to quantify the shadowing effect of caisson groups. Regarding the cyclic response, several cycles of large-amplitude loading are sufficient to reduce the ultimate bearing capacity of caisson(s) to below the self-weight of the inner soil plug(s), indicating a transition of failure mechanism.

DESIGN INVESTIGATION ON FOOT DEFORMITIES WORKING FOOTWEAR

Footwear was planned to protect the feet from the environment. Choosing the right footwear based on foot conditions and requirements enabling to reduce the risk of injury, fast fatigue, and foot pains. Good footwear should provide stability to the joints of the foot and a foundation upon which the foot can function. The objective of this study is to provide information that will assist researchers and designers in identifying, designing and offering appropriate and better working footwear designs for those with foot deformities. Two identified workers from the footwear factory with congenital foot deformities participated in this prospective intervention study for over 12 months. An interview and a video on how the participant wears and walk with normal commercial shoes were recorded. The physical examination was also assessed including the footwear, feet, legs, and hips of the subjects. They were examined with a focus on the areas of deformities. Each leg has different shape and concerns. Hence, each footwear designed for those with foot deformities must be customized base on the factors of type of deformities, body size and the remaining skeletal structure and muscular. With proper modification, people who have foot deformities and unable to buy suitable footwear will be able to relieve the pain and at the same time increase the individual motivation in job satisfaction, motivation or enthusiasm to work and reducing levels of stress or emotional upset.

Case of Deep Venous Thrombosis Secondary to May-Thurner Syndrome

May-Thurner syndrome (MTS) remains an underdiagnosed cause of venous thromboembolism (VTE) because most individuals with MTS anatomy are asymptomatic. The most common variant of MTS is due to compression of the left iliac vein between the overlying right common iliac artery and the fifth lumbar vertebrae. Clinical features include chronic venous hypertension that usually presents as lower extremity pain and swelling. Acute VTE almost exclusively affects the left lower extremity. In cases of acute VTE of an unknown etiology, MTS should be considered when other more common pathologies have been ruled out. A 65-year-old African American gentleman with past medical history of hypertension and coronary artery disease presented with left lower extremity pain and swelling of the leg for five days. He had no history of leg trauma, recent surgery, bed rest, travel, malignancy, previous clotting episodes or family history of hypercoagulable disorders. Patient regularly ambulates. He is a lifetime non-smoker and does not take any medication. His left lower extremity was swollen from the calf down to the ankle and foot, tense, erythematous and tender to palpation. Dorsalis pedis and posterior tibial pulses were weakly palpable. Homan’s sign was appreciated while the rest of the physical exam was unremarkable. Duplex ultrasound of the left lower extremity showed thrombi in the left popliteal, posterior tibial and peroneal veins. CT abdomen and pelvis with IV contrast demonstrated significant compression of the left common iliac vein as it crosses posterior to the left internal iliac artery, consistent with MTS. Spiral chest CT was significant for subsegmental emboli in the bilateral lobe pulmonary arteries. Patient was started on anticoagulation, then he was referred to an advanced vascular center to consider the need for angioplasty and stenting and for possible thrombolysis. MTS was first described in 1908 by Virchow, who observed that iliofemoral vein thrombosis was five times more likely to occur in the left leg than in the right leg. May and Thurner discovered an anatomical variant where the right iliac artery compressed the left iliac vein against the fifth lumbar vertebra. Clinicians should have a high index of suspicion for MTS in the presence of unprovoked DVT in the left lower extremity, and/or signs of chronic venous hypertension. Angioplasty and stenting of the affected lesion is the definitive treatment for MTS, while anticoagulation management is similar to patients with provoked VTE. Therefore, it can be argued that in patients with an unexplained cause of VTE, investigation for MTS if clinically suspected can impact management decisions.

PO 18191 - Congenital distal tibiofibular diastasis

Introduction: Congenital distal tibiofibular diastasis is an extremely rare entity of unknown etiology that compromises the feet and ankles with different degrees of deformity, although in general, the feet show equinovarus deformity, and the talus is proximally dislocated due to the separation of the distal tibial and fibular epiphyses. There are few reports of this disorder in the literature, and most describe cases that ultimately lead to limb amputation. We present the cases of 2 patients treated from birth to skeletal maturity. Methods: Two female patients with clubfoot at birth were diagnosed with congenital distal tibiofibular diastasis. One of them had the deformity of the right foot, and the other had deformity of both limbs. Both patients underwent early distal tibiofibular arthrodesis and serial stretching of the compromised feet and legs. Results: After 20 years of clinical follow-up and after reaching skeletal maturity, both patients had plantigrade feet without significant shortening of the lower limbs or pain, and both performed activities of daily living without restrictions, wearing conventional shoes. Conclusion: Early distal tibiofibular arthrodesis followed by limb stretching was effective for treating congenital distal tibiofibular diastasis and is a good alternative to amputation, which is indicated in the literature.

PO 18035 - Metatarsophalangeal arthrodesis for hallux valgus treatment

Introduction: Hallux valgus is the most common deformity of the adult foot and is often highly debilitating, especially when severe. First metatarsophalangeal arthrodesis (FMTPA) is a reliable method of hallux valgus correction, with a high success rate and a low relapse rate. This study assesses the union rate and degree of satisfaction and compares the pre- and postoperative American Orthopedic Foot and Ankle Society (AOFAS) scale scores of patients subjected to FMTPA for hallux valgus treatment. This study is a retrospective review of 29 feet that underwent FMTPA fixed with crossed 1.5-mm Kirschner wires, with or without cerclage. Union was assessed radiologically and clinically. Methods: From March 2011 to April 2018, 23 patients diagnosed with hallux valgus underwent surgery using the FMTPA technique fixed with crossed Kirschner wires. One patient died of unrelated causes, and another was not located for the review, leaving a total of 21 patients for the analysis (29 feet). Eight patients were operated on bilaterally, 6 underwent operation of the right foot, and 7 underwent surgery of the left foot. The mean follow-up was 32 months (7-94 months), and the mean age at the time of surgery was 69 years (45-88). Results: The AOFAS score improved from a mean of 26.8 points before the surgery (10-55) to a mean of 77.6 points after (57-90). The patients were fully satisfied with 17 of the 29 procedures and satisfied with reservations in 12 cases. No patient was dissatisfied with the outcome. Clinical and radiological union was observed in all cases. The orthopedic hardware was removed due to pain or local discomfort in 18 feet (62% of cases). Conclusion: FMTPA fixed with crossed Kirschner wires for hallux valgus treatment is highly effective, with a high union rate and a high degree of patient satisfaction.

Open reduction and osteotomy for old pilon fracture

Objective To investigate the efficacy of open reduction and osteotomy combined with internal fixation to reconstruct the distal tibial articular surface in the treatment of old pilon fracture. Methods A retrospective case series study was conducted to analyze the clinical data of 20 patients with old pilon fracture admitted to Zhengzhou Orthopaedic Hospital from July 2014 to February 2018. There were 14 males and six females, aged 21-45 years, with an average of 31.5 years. According to AO classification, there were four patients with C1 type, seven with C2 type and nine with C3 type, all of which were closed fractures. Eleven patients received non-operative treatment while nine patients underwent surgeries. After the surgery, malunion was seen in eight patients, and incomplete union in 12 patients. There were eight patients with posterior articular surface collapse of distal tibia, seven patients with anterior articular surface collapse of distal tibia, three patients with varus deformity and two patients with valgus deformity. All patients were treated with open reduction and osteotomy with internal fixation to reconstruct the articular surface of distal tibia. The time of fracture healing was recorded, and the Visual Analogue Scale (VAS), ankle flexion and extension range of motion, and AOFAS ankle-hind foot function score were compared before and at the last follow-up. The complications were recorded. Results All patients were followed up for 7-36 months, with an average of 26.4 months. Fracture healing time was 3-7 months, with an average of 4.1 months. At the last follow-up, VAS, ankle metatarsal flexion, dorsal extension and AOFAS scores were significantly improved compared with those before operation [(1.9±1.0)points vs. (6.6±1.4)points, (31.6±2.4)° vs. (18.5±4.4)°, (25.7±2.7)° vs. (15.6±2.7)°, (79.6±7.3)points vs. (42.6±5.6)points] (P<0.05). One patient developed severe ankle traumatic arthritis 7 months after operation and underwent fusion of ankle joint. Conclusion For old pilon fracture, open reduction and osteotomy to reconstruct the distal tibial articular surface can effectively relieve pain, improve joint mobility and restore ankle function. Key words: Osteotomy; Foot deformities; Pilon fracture

Primary tumor (tumoral) calcification is a rare disease in the practice of a rheumatologist and orthopedist: experience with the use of an interleukin-1 inhibitor in combination with surgical correction

Background. Primary tumoral calcinosis is an orphan disease. There are few data in the literature on the incidence of this disease, as well as clinical recommendations for treatment.&#x0D; Clinical case. This report presents the case of an 11.5-year-old boy with primary tumoral calcinosis and equinus deformity of the foot. The patient had multiple foci of the subcutaneal calcification, cannot walk, experienced fatigue, and had high fever and equinus deformity of the left foot. Immunological and genetic studies were performed, but any specific mutations were not found. After the diagnosis was verified and interleukin-1 inhibitor therapy was prescribed, there was a significant positive trend observed in the patient: a significant improvement in the patients general condition, a decrease in the number of calcinates, and a reduction in inflammation. Calcification of the Achilles tendon and gastrocnemius muscle was the cause of the deformity of the left foot.&#x0D; Discussion. Significant improvement was achieved during treatment: the boy started walking, fatigue was decreased, no new calcificates were formed, and inflammation was under the control. Using an inhibitor of interleukin-1 as a permanent therapy of primary tumoral calcification allowed performsurgical treatment without complications from an operation site, as well as a relapse of deformity.&#x0D; Conclusion. The clinical case presented here demonstrated the application of an interdisciplinary approach to the treatment of an extremely rare disease.

Radiographic Predictors for Adverse Outcomes Following Surgical Correction of Hammertoe Deformity

Category:Lesser ToesIntroduction/Purpose:Hammertoe deformities are common, often painful deformities of the lesser foot and are known to severely affect physical function. When patients seek surgical management, x-ray imagining is utilized for diagnosis, evaluation for surgical candidacy, and selection of the operative technique. Postoperatively, radiographs are retaken to assess bone health, healing status, and alignment. Despite their frequent use, no previous data support particular X-ray findings as being indicative of clinical presentation nor surgical outcomes. The aim of this study is to identify specific radiographic parameters that are predictive of pain and function outcomes after surgical correction of hammertoe deformity.Methods:Prospectively collected data was reviewed on 116 patients who underwent hammertoe correctional surgery. Patient demographics, comorbidities, and postsurgical complications were recorded from their electronic medical records. Clinical outcomes were assessed utilizing preoperative and postoperative pain Visual Analogue Scale (VAS) and Short Form Health Survey Physical Component (SF-36 PCS) scores with 1-year follow-up. Radiographs were scored by a foot & ankle fellowship-trained orthopaedic surgeon to assess preoperative severity, postoperative joint fusion, and both pre- and postoperative joint instability. Data was examined using chi-squared, t-test, and ANOVA analyses.Results:Preoperatively, 14.7% of patients had a deformity classified radiographically as mild, 37.1% as moderate, and 48.3% as severe. X-rays prior to surgery showed that 65.5% had MTP joint instability, 9.5% had joint dislocation, and 18.1% had joint arthritis. Postoperatively, 78.5% had PIP joint fusion, 38.8% had MTP joint arthritis, and 17.2% had MTP joint instability. A significant association was found between postoperative MTP joint instability and a lower 1-year SF-36 PCS (p=0.0032). There were no associations found between the other radiographic findings and postoperative outcomes, and no parameters were associated with pain VAS scores.Conclusion:After undergoing surgical correction of hammertoe deformity, the postoperative radiographic finding of MTP joint instability was determined to be predictive of physical function. However, neither metatarsophalangeal joint arthritis nor PIP fusion were predictive of outcomes. This work informs foot and ankle specialists that proper joint alignment and stabilization is critical to ensuring success in hammertoe surgery.

Correlation between FPI and radiologic measurement and in-shoe plantar pressure in the normal subjects

Calcaneo-cuboid-cuneiform (triple C) osteotomies correct all levels of deformity of flexible planovalgus feet (PVF) in patients with cerebral palsy (CP). The objective was assessing short term results and the hypothesis was that static pedobarography correlates with radiological parameters as outcome measures.A prospective case series of consecutive skeletally immature ambulatory spastic CP patients above the age of 4 years who underwent triple C for PVF. Assessment was done using static pedobarography and standing dorsoplantar (DP) and lateral radiographs. The calcaneal pitch, lateral talocalcaneal, lateral and DP talo-first metatarsal, and DP talonavicular coverage angles were measured.Eighteen feet (12 patients) were analyzed. Postoperative changes in lateral and DP talo-first metatarsal, and DP talonavicular coverage angles were statistically significant (P-value = 0 with paired T-test). Post operative foot pressure changes were significant and highest in mid-foot. Both outcomes were related together with a p-value of 1 using McNemar test.The triple C and associated soft tissue procedures reliably corrected PVF deformities. Static pedobarography can be used for postoperative assessment of adequate correction.

Patient Knowledge Regarding Radiation Exposure From Foot and Ankle Imaging.

Foot and ankle surgeons routinely prescribe diagnostic imaging that exposes patients to potentially harmful ionizing radiation. It is unclear how well patients understand the radiation to which they are exposed. In this study, 946 consecutive new patients were surveyed regarding medical imaging and radiation exposure prior to their first appointment. Respondents compared the amount of radiation associated with chest X-rays (CXRs) with various types of foot and ankle imaging. Results were compared with actual values of radiation exposure from the published literature. Of 946 patients surveyed, 841 (88.9%) participated. Most had private insurance (82.8%) and a bachelor's degree or higher (60.6%). Most believed that foot X-ray, ankle X-ray, "low dose" foot and ankle computed tomography (CT) scan (alluding to cone-beam CT), and traditional foot and ankle CT scan contain similar amounts of ionizing radiation to CXR. This contradicts the published literature that suggests that the actual exposure to patients is 0.006, 0.006, 0.127, and 0.833 CXR equivalents of radiation, respectively. Of patients who had undergone an X-ray, 55.9% thought about the issue of radiation prior to the study, whereas 46.1% of those undergoing a CT scan considered radiation prior to the exam. Similarly, 35.2% and 27.6% reported their doctor having discussed radiation with them prior to obtaining an X-ray and CT scan, respectively. Patients greatly overestimate the radiation exposure associated with plain film X-rays and cone-beam CT scans of the foot and ankle, and may benefit from increased counseling regarding the relatively low radiation exposure associated with these imaging modalities.Level of Evidence: Level III: Prospective questionnaire.

Genetic Markers of the Cattle Foot and Mouth Disease Virus: Genomic Analysis

Objective of this work was to search for genome loci of various types of foot and mouth disease (FMD) virus, characterized by the lowest variability, to be used as genetic markers in the PCR-indication of the virus.Materials and methods. The resources of the National Center for Biotechnology Information (NCBI) and BLAST and Vector NTI 9.1.0 software utilities were employed in the research. Plasmid DNA with marker insertion was utilized for PCR amplification.Results and discussion. The nucleotide sequences of FMD virus genomes, the types A, Asia-1, C, O and SAT (1, 2 and 3), were analyzed. In the process of aligning of isolate genomes of each type, potentially conservative sites were identified. The comparison between these loci has revealed one most conserved locus, and the subsequent BLAST analysis has established its high specificity to FMD virus genome. Primers and a probe were selected for this locus. In addition, the oligonucleotide primers were selected for the three genes included in the cattle genome that are least homologous to the specific oligonucleotides. The primers/probe were used as internal control of amplification. To control the progress of amplification, a positive control has been developed that has a nucleotide sequence of the marker region of FMD virus genome. It was found out that genomes of certain virus isolates show high level of polymorphism in relation to PCR-probe (12 isolates by A, Asia-1, SAT1, and SAT2 serotypes). However, modifications of the PCR-probe (Pas FMDV and Psat FMDV) allow for elimination of the effect of such variability on the number of virus isolates identification. Nucleotide sequences of the primers, probes and positive controls are presented in the tables.

Abnormal hypersynchronization of body balance control system in children with post-burn foot deformity

Relevance. Treatment of children with post-burn foot deformities is an important task of reconstructive plastic surgery. The scars formed on the back surface of the feet, even with adequate surgical approach, in the acute period of thermal injury, further often lead to deformities of the entire foot, which leads to a derangement of its support function. The importance of the problem lies in the fact that with the growth of the child, secondary abnormal changes develop on the part of the joints of the lower extremities and the spine, leading to impaired locomotor function, including deviations in the body balance control system.&#x0D; Purpose of the study. To study postural stability in children with post-burn foot deformities before and after surgical treatment.&#x0D; Material and methods. The stabilometric study was conducted in 12 patients with post-burn cicatricial foot deformity, the average age of the patients was 9.8 ± 0.93 years old. The control group consisted of 12 children of the same age with no signs of orthopedic abnormality. To assess the results, the methods of descriptive statistics with the inclusion of correlation and regression analysis were used.&#x0D; Results. In patients with post-burn cicatricial deformity of the foot at the pre-treatment stage, a compensatory redistribution of the static load towards the intact lower limb was revealed. Analysis of postural control indicators in patients of the main group showed an abnormal increase in the synchronization of the system of body balance control. After reconstructive operations on the affected foot, symmetry of the distribution of the load and restoration of the support of the limb of the affected side were noted. Correlation analysis revealed a pronounced decrease in abnormal hypersynchronization between stabilometric parameters, which may indicate a trend towards normalization of the postural control strategy in patients after treatment.&#x0D; Conclusion. Elimination of post-burn foot deformity contributed to the restoration of its anatomical shape and was accompanied by pronounced positive dynamics in the state of the system of vertical balance of the patient’s body.

Effects of midsole bending stiffness on arch deformation of the human foot during running

It has been postulated that the arch of the human foot stores and releases elastic strain energy during locomotion via ligamentous and tendinous structures (Ker, Bennett, Bibby, Kester, & Alexander...

Percutaneous minimally invasive screwing assisted by 3D printing patient-specific external guide template for pelvic and acetabular fractures

Objective To evaluate the efficacy and safety of 3D printing patient-specific external guide template in assisting minimally invasive screwing for treatment of pelvic and acetabular fractures. Methods The clinical and follow-up data of 39 pelvic or acetabular fractures were retrospectively analyzed which had been treated from June 2016 to February 2018 at Department of Orthopaedics, Wuhan Union Hospital. The patients were divided into a template group and a freehand group. In the template group, there were 14 men and 7 women with an age of 46.3±18.2 years and 17 pelvic fractures and 4 acetabular fractures; in the freehand group, there were 12 men and 6 women with an age of 43.8±12.2 years and 14 pelvic fractures and 4 acetabular fractures. The 2 groups were compared in terms of operation time, fluoroscopic frequency, guide wire adjustments, fracture reduction, screw penetration rate, function evaluation and adverse events. Results All the 39 patients were followed up for 9 to 13 months (average, 11.6 months). A total of 42 screws were placed in the template group and 35 screws in the freehand group. The values of operation time (43.8±22.2 min), fluoroscopic frequency (29.6±10.7 times) and guide wire adjustments (1.8±1.2 times) in the external guide template group were all significantly lower than those in the freehand group (73.8±22.6 min, 54.6±16.5 times and 9.8±2.8 times, respectively) (P 0.05). One case in the freehand group experienced numbness after operation on unilateral dorsi pedis which disappeared at 3-month follow-up. Conclusion The 3D printing patient-specific external guide template can reduce fluoroscopic frequency, save operation time and improve accuracy of screw insertion, providing a new means for minimally invasive treatment of pelvis and acetabular fractures. Key words: Pelvis; Acetabulum; Fractures, bone; Surgical procedures, minimally invasive; 3D printing technology

Determination of the Moisture Content and the Generation of Airborne Particulate Matter From Various Types of Footing From Indoor Riding Arenas Considered to Have Optimal Rideability

It has been known for some years now that the occurrence of lameness in horses is closely related to the characteristics of the riding surface and that respiratory tract diseases can be induced by airborne particles. To ensure both optimal rideability (e.g., grip, elasticity, etc.) and low dust production, riding surfaces have to be regularly attended to, which also includes watering the floor. However, at present, it is not known what the individual moisture content of the various types of riding surface should be to ensure optimal rideability or what their potential for releasing dust is at the time of optimal rideability. The aim of the present study was to determine the moisture content, the density as weight/liter, particle size distribution and the release of airborne particulate matter (APM) with a diameter <10 μm (PM10) of the footing material from three types of indoor riding arena surfaces considered to have optimal rideability. Loose footing material samples were taken from the surfaces of 25 indoor riding arenas [5 pure sand (S), 10 sand-wood chips (SW), and 10 sand-fibre (SF)] and investigated under standardized conditions. The evaluation of the surface's rideability was carried out subjectively by the respective facility manager. The ambient particulate monitor TEOM 1400a was used to measure the PM10 production from the footing samples. Although, according to the facility managers, all of the investigated riding surfaces had optimal rideability at the time of sampling; obvious differences could be found with respect to their moisture content, density, particle size distribution, and release of APM, both between and within the 25 indoor arenas. The moisture content of SW (14.96 ± 4.00%) was significantly higher than that of SF (8.99 ± 2.95%; P = .0046), but the S moisture content (10.82 ± 2.65%) was not significantly different to either of them (S vs. SW: P = .0982 and S vs. SF: P = .2446). With respect to the release of APM, it could be shown that the average release from SF was 2.50–5.47 times higher than either for the S or SW (CSum—S: 12.81 mg/m³air, SW: 5.86 mg/m³air, and SF: 32.06 mg/m³air; t-test—S vs. SW: P = .3882, S vs. SF: P = .2560, and SW vs. SF: P = .0031). The reason for this was the extremely high APM release in three of the ten investigated SF samples. In addition, significant differences were also observed in the APM release within the three individual types of footing. Although no factors significantly affected the release of APM in either the S or SW footings, the density of the SF footing was found to have a significant influence on its APM production: the higher the density, the lower the APM release. The density itself was related to both the footing's moisture content and fiber content. The reason why SF footings with a low density (associated with a high fibrous material content) and a high moisture content tended to cause a greater release of APM is that there was a segregation of the fibrous material caused by the measuring technique used. This led to the fibrous material rising to the top of the sample resulting in a release of APM directly from this material. To prevent such a high release of particles from SF footings with a high fiber content occurring in practice, such footings should be regularly and adequately watered, and any segregation of the fibrous material should be prevented using suitable arena grooming techniques.