Understanding multicentric haemangioendothelioma: diagnostic dilemmas and treatment strategies.

Epithelioid haemangioendothelioma (EH) is a rare malignant vascular tumour occurring mainly in the liver and lungs, with bones being a rare site and primarily seen in the adult population. This case presents a male patient in his 40s who presented to the outpatient department with a chief issue of a painless swelling over the inguinal region for 4 months, gradually increasing in size, along with a history of a gradually enlarging, painless mass on his left knee over the past 5 years. Despite occasional discomfort during physical activities, the mass exhibited no associated trauma, fever, weight loss or systemic symptoms. Physical examination revealed a firm mass on the left knee and a matted lymph nodal swelling in the left inguinal region. Subsequent imaging studies identified multiple soft tissue lesions, osseous involvement and pulmonary metastases, suggestive of multicentric haemangioendothelioma. The patient underwent surgical excision of the inguinal mass and fixation of a pathological fracture in the left femur. He is currently undergoing chemotherapy and is scheduled for regular follow-up appointments. This case underscores the importance of thorough diagnostic evaluation and multidisciplinary management in complex oncological conditions like multicentric haemangioendothelioma.

Registry-based cohort study comparing percentages of patients reaching PASS for knee function outcomes after revision ACLR compared to primary ACLR.

OBJECTIVES: Reaching the Patient-Acceptable Symptom State (PASS) threshold for the Knee injury and Osteoarthritis Outcome Score (KOOS) has previously been reported to successfully identify individuals experiencing clinical success after anterior cruciate ligament reconstruction (ACLR). Thus, the objectives of this study were to examine and compare the percentages of patients meeting PASS thresholds for the different KOOS subscales 1 year postoperatively after primary ACLR compared with revision ACLR (rACLR) and multiply revised ACLR (mrACLR), and second, to examine the predictors for reaching PASS for KOOS Quality of Life (QoL) and Function in Sport and Recreation (Sport/Rec) after mrACLR. DESIGN: Prospective observational registry study. SETTING: The data used in this study was obtained from the Swedish National Ligament Registry and collected between 2005 and 2020. PARTICIPANTS: The study sample was divided into three different groups: (1) primary ACLR, (2) rACLR and (3) mrACLR. Data on patient demographic, injury and surgical characteristics were obtained as well as mean 1-year postoperative scores for KOOS subscales and the per cent of patients meeting PASS for each subscale. Additionally, the predictors of reaching PASS for KOOS Sport/Rec, and QoL subscales were evaluated in patients undergoing mrACLR. RESULTS: Of the 22 928 patients included in the study, 1144 underwent rACLR and 36 underwent mrACLR. Across all KOOS subscales, the percentage of patients meeting PASS thresholds was statistically lower for rACLR compared with primary ACLR (KOOS Symptoms 22.5% vs 32.9%, KOOS Pain 84.9% vs 92.9%, KOOS Activities of Daily Living 23.5% vs 31.4%, KOOS Sport/Rec 26.3% vs 45.6%, KOOS QoL 26.9% vs 51.4%). Percentages of patients reaching PASS thresholds for all KOOS subscales were comparable between patients undergoing rACLR versus mrACLR. No predictive factors were found to be associated with reaching PASS for KOOS QoL and KOOS Sport/Rec 1 year postoperatively after mrACLR. CONCLUSION: Patients undergoing ACLR in the revision setting had lower rates of reaching acceptable symptom states for functional knee outcomes than those undergoing primary ACLR. LEVEL OF EVIDENCE: Prospective observational registry study, level of evidence II.

Effectiveness of a physiotherapy self-management programme for adult patients with chronic non-specific low back pain in low- and middle-income countries: protocol for a systematic review and meta-analysis.

INTRODUCTION: Chronic non-specific low back pain (CNLBP) is among the most common musculoskeletal system conditions reported worldwide; however, few studies are available from low- and middle-income countries (LMICs). Self-management is a set of tasks performed by the patient aiming at managing their symptoms and interference in activities, mood and relationships due to pain. A physiotherapy-guided self-management programme (SMP) following a biopsychosocial approach has been reported as effective and affordable in the management of CNLBP in high-income countries. The objective of this systematic review is to determine the overall effectiveness of SMPs for adults with CNLBP in LMICs. METHODS AND ANALYSIS: In this systematic review, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Protocol (PRISMA-P) guidelines will be followed. A three-step search strategy will be used to search the electronic databases (PubMed, MEDLINE, SPORTDiscus, Scopus and CINAHL, Academic Search Complete and PEDro) for randomised controlled trials assessing the effectiveness of physiotherapy-guided self-management for CNLBP among adult participants in LMICs. The processes of screening search results for eligible studies, extracting data from included studies and appraising will be done independently by at least two review authors. Random effects meta-analysis will be used to synthesise results and heterogeneity will be assessed using the I2 test statistic and χ2 test. ETHICS AND DISSEMINATION: Ethics clearance was obtained for the broader PhD study on the development of a physiotherapy-guided SMP for adult people with CNLBP in Limpopo Province, South Africa. The results of the manuscript for this protocol will be published in peer-reviewed journals and also presented at conferences, symposia, and congresses. PROSPERO REGISTRATION NUMBER: CRD42023399572.

Health-related quality of life for children with anterior cruciate ligament deficiency: Ensuring content validity of the new KIDS-KNEES-ACL questionnaire.

PURPOSE: The existing knee-specific pediatric patient-reported outcome measures (PROMs) lack content and construct validity for children with anterior cruciate ligament (ACL) injury. This impairs their accuracy which can lead to false interpretations of data and inaccurate clinical guidelines. The purpose of this study was to develop a content-valid PROM for children with an ACL injury. METHODS: The process adhered to the COnsensus-based Standards for the selection of health Measurement INstruments guidelines for PROM development. Informants were children with ACL deficiency and sampled based on age, sex, and treatment. Semistructured interviews were conducted exploring themes within the International Classification of Functioning, Disability and Health model. Interviews continued beyond data saturation. By thematic analysis and by probing items from the adult PROM 'KNEES-ACL', new themes and items emerged. Content coverage, relevance and understandability were continuously evaluated. All interviews were recorded and transcribed verbatim. The NVivo 12 software was used for data analysis and coding of items. RESULTS: A PROM of 60 items across nine subscales was formed. From cognitive interviews, 19 new items emerged. Forty-one of 55 items from KNEES-ACL were endorsed as relevant; however, all required rewording to ensure understandability. Substantial differences in the psychosocial impact between adults and children were observed. The children experienced a more considerable negative psychosocial impact caused by a loss of participation in sports, lower self-confidence and loss of social networks. This resulted in four new domains. The physical issues were similar to adults, with few exceptions. CONCLUSION: The 'KIDS-KNEES-ACL' 1.0 (qualitative version) was developed. This version will be subjected to psychometric analysis, resulting in adequate measurement properties of the final KIDS-KNEES-ACL 2.0. As the only adequate pediatric ACL-specific PROM, its use in clinical trials and databases will enhance PROM data quality, and strengthen clinical guidelines and thus the treatment of children with ACL injury. LEVEL OF EVIDENCE: Not applicable.

Profile of Sport and Exercise Physician trainee's clinical practice within Australasia in 2019: a cross-sectional study.

Objective: To identify the patient population profile and the spectrum of training activities and influencing factors of Australasian College of Sport and Exercise Physician (ACSEP) trainees. Design: Retrospective cross-sectional design. Setting: Training settings for ACSEP trainees. Participants: Twenty ACSEP trainees undertaking full-time training in training period 2 of the 2019 training year (1 August 2019-31 January 2020). Exclusion criteria were trainees undertaking part time study and new fellows who completed their fellowship exams in 2019. Independent variables: Patient and practitioner demographics. Method: Retrospective cross-sectional design. Main outcome measurements: Patient data recorded in ACSEP trainees' logbook. Short questionnaire capturing pertinent trainee demographics. Results: Most ACSEP trainee patients are adults aged 18-65 years of age (78.2%), presenting with knee (18.7%), ankle (17%) and spinal complaints (13.1%) in clinical practice or sporting team environments. Youths 10-17 make up 13.1% of presentations and older adults 66 years and older make up 8%. Only Australian trainees are engaging in additional training activities, such as surgical assisting outside of the clinic or sporting team environment. Conclusion: Australasian Sport and Exercise Physician trainees appear to consult primarily musculoskeletal complaints, including providing broader care to paediatric and older populations, and work with sporting teams. There are differences between Australia and New Zealand trainee employment conditions, which appear to be affecting training experiences. These differences warrant consideration to ensure equitable training experiences and financial stability for trainees.

Evaluation of Tibial Slope on Radiographs in Pediatric Patients With Tibial Spine Fractures: An Age- and Sex-Matched Study.

Background: A recent study has reported that the radiographic measurement of posterior tibial slope (PTS) is larger in male pediatric patients with tibial spine fractures (TSF) than in controls. However, they found no difference in PTS between female patients and controls. Purpose: (1) To identify whether PTS is larger in female pediatric patients with TSF than in female controls and (2) to validate the relationship between PTS and pediatric TSF in male patients. Study Design: Cross-sectional study; Level of evidence, 3. Methods: After an a priori power analysis, 84 pediatric patients with TSF (50 female patients and 34 male patients) and 84 age- and sex-matched controls were enrolled in this study. Demographic information, including sex, age, and race, was recorded. Skeletal maturity was determined based on the stage of epiphyseal union on knee radiographs. PTS was defined as the angle between a line perpendicular to the longitudinal axis of the tibia and the posterior inclination of the medial tibial plateau on standard knee lateral radiographs. Results: The mean age when the TSF occurred was 11.2 ± 2.7 years for female patients and 12.9 ± 2.5 years for male patients. There was no significant difference in skeletal maturity between female patients and female controls or between male patients and male controls. The mean PTS was not significantly different between female patients (8.8°± 2.8°) and female controls (8.3°± 3.1°) (P = .366) or between male patients (9.0°± 2.8°) and male controls (9.3°± 2.6°) (P = .675). Those with a PTS >1 SD (2.9°) above the mean (8.8°) had no greater odds (1.0 [95% CI, 0.4-2.5]; P≥ .999) of having a TSF than others. Conclusion: PTS was not found to be a risk factor for pediatric TSF in female or male patients in this study.

Publications and ranking in orthopaedics and sports medicine of European countries during the last three decades: A bibliometric analysis.

Introduction: The present investigation examined the trend of publications and ranking in Orthopaedics and Sports Medicine of European countries during the years 1996 to 2022 and compared these with all the regions globally. Methods: In September 2023, the SCOPUS data of publications in Orthopaedics and Sports Medicine from the SCImago Journal & Country Rank website were retrieved. All the data from Western and Eastern Europe were extracted from the overall data of the global countries and merged into Excel files, for each of the years 1996-2022 and 2022. Results: Western European countries contributed significantly to the global share of publications in Orthopaedics and Sports Medicine with nearly 1/3rd of the total publications. Eastern European countries' contribution was minimal to the global publications and was almost 10 times less than the Western European countries. The total number of publications in the area of Orthopaedics and Sports Medicine from 1996 to 2022 at the European scale was led by the United Kingdom (N = 51510) and has maintained its supremacy until recently, in 2022. Amongst Western European countries, during the cumulative period of 1996-2022, the maximum contributions were made by the United Kingdom (N = 51510), and also in 2022, the United Kingdom contributed maximally (N = 3339). In the cumulative period of 1996-2022, Poland contributed maximally (N = 4049) among the Eastern European countries. In 2022, the maximum contribution from the Eastern European countries came from the Russian Federation (N = 462). Conclusion: The European continent is the major contributor to Orthopaedics and Sports Medicine research and publications, with almost 1/3rd of the global share of publications. Western European countries are far ahead in their contributions than Eastern European countries.

Qualitative and quantitative return-to-sport test battery and second anterior cruciate ligament injury risk factors.

Objective: To determine risk factors for second anterior cruciate ligament (ACL) injury following primary ACL reconstruction (ACLR) using return-to-sport (RTS) tests consisting of qualitative and quantitative measures in young athletes. Methods: A case-control study design was used, and a retrospective review of adolescent athletes after primary ACLR was performed. All athletes completed an RTS test consisting of qualitative and quantitative assessments and psychological assessments with the Tampa Scale of Kinesiophobia. Athlete demographics, surgical characteristics and sports participation were also examined. A binary logistic regression was performed to verify an independent association between risk factors and second ACL injury using adjusted OR (aORs), 95% CI and p<0.05. Results: In 72 eligible athletes, 12 (16.7%) suffered a second ACL injury. The mean Tegner activity level was 8.4+1.1, and the mean time from ACLR to RTS test completion was 10.4+2.9 months. One variable that showed the lowest p-value in the preliminary analysis was entered into the binary logistic regression model, which resulted in that qualitative assessment of knee valgus during the sidestep cut was associated with second ACL injury (aOR=4.64, 95% CI: 1.18 to 18.23, p=0.03). Conclusion: Athletes who demonstrated excessive dynamic knee valgus on the involved limb during the sidestep cut were approximately 4.6 times more likely to suffer a second ACL injury.

Youth Sport Specialization: Current Concepts and Clinical Guides.

The concept of youth sport specialization has evolved over the past decade, from a focus on the risk of overuse injury to a broader awareness of its effects on mental health, social well-being, quality of life, growth and maturation, sport performance, and long-term athletic success. This review article considers a recently revised definition of youth sport specialization, as well as guidelines and consensus statements from various sports medicine organizations, with practical applications for young athletes.

Patellofemoral Instability in Pediatric and Adolescent Athletes: A Review of Risk Factors and Treatments.

Pediatric patellar instability can impair function and restrict activity participation. If left untreated, it can lead to a degenerative knee. The incidence of patellar dislocations is highest in adolescents between 10 and 17 years of age; more than half of all first-time patellar dislocations occur during sports. This article reviews the evidence of risk factors for traumatic patellar instability, surgical interventions, and return-to-sport (RTS) considerations for pediatric and adolescent athletes. Anatomic risk factors for patellar instability in pediatric and adolescent patients include trochlear dysplasia, elevated tibial tuberosity-trochlear groove (TT-TG) distance, patella alta, genu valgum, femoral anteversion and tibial torsion, and hyperlaxity.

An Explorative Anatomical Study on Inter-Individual Variation of the Tibial Nerve and Landmarks for Perineural Anesthesia in Horses.

Perineural anesthesia of the tibial nerve can be performed ultrasound-guided or blindly, with the latter still being commonly used in equine practice due to practical constraints, despite its lower accuracy and hence, common failure to achieve desensitization. This may be associated with anatomical variations or inadequate landmarks for injection. To examine the course of the tibial nerve, document potential anatomical variations, and determine optimal landmarks for perineural injection, dissection was conducted along the medial aspect of the tibia in 10 paired cadaver hindlimbs. No anatomical variations of the tibial nerve were observed. Mean tibial nerve thickness was 6 ± 1 mm. The junction with the plantar nerves was located at a maximum of 85 mm and the junction with the medial cutaneous branch was at a maximum of 150 mm proximal to the proximal aspect of the calcaneal tubercle. The mean distance of the tibial nerve to the cranial border of the superficial digital flexor was 11 ± 6 mm. In conclusion, problems with perineural anesthesia of the tibial nerve cannot simply be attributed to anatomical variations. The thickness of the nerve and the amount of perineural tissue may present specific challenges for achieving adequate desensitization. Our results support the generally recommended site for tibial nerve perineural injection at 100 mm proximal to the calcaneal tubercle and 11 mm cranial to the superficial digital flexor.

Reliability of Ultrasound Assessment of Hamstring Morphology, Quality, and Stiffness Among Healthy Adults and Athletes: A Systematic Review.

CONTEXT: The incidence and recurrence rate of hamstring strain injuries remain persistently high, with recurrent injuries leading to increased time lost during play and extended recovery periods compared with initial injury. Ultrasound imaging assesses important factors such as hamstring fascicle length (FL), pennation angle (PA), cross-sectional area (CSA), muscle thickness (MT), echo intensity (EI), and shear wave elastography (SWE), all impacting athletic performance. However, its reliability must be established before employing any measurement tool in research or clinical settings. OBJECTIVES: To determine the reliability and measurement error of ultrasound for assessing hamstring FL, PA, CSA, MT, EI, and SWE among healthy adults and athletes; to synthesize the information regarding the operationalization of ultrasound. EVIDENCE ACQUISITION: A systematic literature search was done from January 1990 to February 5, 2023, to identify reliability and validity studies of hamstring ultrasound assessment published in peer-reviewed journals with identifiable methodology of outcome measures. EVIDENCE SYNTHESIS: Intraclass correlation coefficient measurement of 14 included studies reported moderate to excellent intrarater, interrater, and test-retest reliabilities of FL, PA, and MT regardless of the site of muscle testing, probe size, and setting, state of muscle, and use of different techniques in the extrapolation of FL. Good to excellent test-retest reliability rates for all hamstring anatomic CSA along midmuscle and different percentages of thigh length using panoramic imaging. Good intrarater reliability of EI regardless of gender and orientation of the probe but with excellent intrarater reliability in transverse scan using maximum region of interest. Good intrarater, interrater, and interday repeatability on SWE with the muscle in a stretched position. CONCLUSION: Evidence from studies with a predominantly low risk of bias shows that ultrasound is a reliable tool to measure hamstring FL, PA, CSA, MT, EI, and SWE in healthy adults and athletes under various experimental conditions.

Annual Trends of High Tibial Osteotomy: Analysis of an Official Registry in Italy.

Background and Objectives: Knee osteoarthritis is a serious burden for modern countries. Timing of surgery and treatment choice are still a matter of controversy in the orthopedic literature. The purpose of this study was to ascertain the incidence and hospitalization trends of high tibial osteotomy in Italy from 2001 to 2016. Materials and Methods: Data are sourced from the National Hospital Discharge Reports (SDO) of the Italian Ministry of Health between 2001 and 2016. Results: A total of 34,402 high tibial osteotomies were performed over the study period in Italy. The cumulative incidence was 3.6 cases per 100,000 residents. The age classes 50-54, 55-59 showed the higher number of procedures. In pediatric patients (0-19 years), high tibial osteotomies are also largely performed. The majority of patients having surgery were men with a M/F ratio of 1.5. The mean age of patients was 44.2 ± 19.2 years. Males were significantly younger than females (43.3 ± 20.7 vs. 45.6 ± 17.7). The average length of hospitalization was 6.1 ± 7.3 days. Over the course of the analysis, a declining trend in hospital stay length was seen. The main primary diagnosis codes were "Varus knee" (736.42 ICD-9-CM code, 33.9%), "Osteoarthrosis, localized, primary, leg region" (715.16 ICD-9-CM code, 9.5%). Conclusions: Over the study period, high tibial osteotomies in Italy almost halved. Varus deformity and knee osteoarthritis are the leading causes requiring high tibial osteotomy. Except for the pediatric setting, results showed that from the 20-24 age class to the 50-54 age class, there was an increasing request for knee osteotomy, whereas in those aged >60 years, the incidence progressively decreased. The evident decline in HTO performed over the years in Italy seems to reflect a minor role for knee osteotomy in the management of knee OA, as it seems to be primarily reserved for younger male patients.

Endoscopic-Assisted Evacuation: A Useful Adjunct for the Management of Prepatellar Hematomas.

Management of prepatellar hematomas can be difficult, and recurrences or persistent oozing are common. Endoscopic-assisted management of these hematomas has not been reported. We present the case of a 44-year-old lady with traumatic prepatellar hematoma who was managed with the evacuation of the hematoma assisted by endoscopic visualization and debridement. She recovered completely within three weeks and remained asymptomatic on the last follow-up at six months. Endoscopic visualization of the hematoma cavity is a useful adjunct to managing prepatellar hematomas, with the potential to identify and control sources of future concerns in wound healing.

Efficacy of soothing cream gel in the range of motion and chronic pain at the shoulder and elbow: protocol of a double-blinded, randomised, placebo-controlled trial.

INTRODUCTION: Upper limb problems have a significant impact on the global population leading to pain and restricted joint mobility, ultimately impacting their quality of life. Traditional treatments, such as non-steroidal anti-inflammatory drugs and corticosteroids, often come with undesirable side effects, prompting patients to seek alternative therapies. In this trial, we hypothesise that soothing cream gel (SCG) will improve range of motion and chronic pain in the shoulder and elbow. The objective of this trial is to evaluate the efficacy of SCG in improving the range of motion and chronic pain in the shoulder and elbow. METHODS AND ANALYSIS: A double-blinded, randomised, placebo-controlled trial is conducted to compare the effects of SCG and placebo gel. SCG contains Vitis vinifera essence, Melaleuca viridiflora essential oil, etc, and is manufactured according to Good Manufacturing Practice standards. The placebo gel will be processed with similar appearance, texture and scent but will lack active ingredients. 70 participants with upper limb problems will be recruited from four study sites, including clinical centres and a sport department at the Chinese University of Hong Kong (CUHK). Participants will be randomly assigned to either treatment group or placebo group for 2 weeks. Primary outcome will be the range of motion in the upper limb, assessed by a goniometer, to measure active flexion and abduction for the shoulder, and active flexion and extension for the elbow. The primary efficacy analyses will be based on the full analysis set following the intention-to-treat principle. ETHICS AND DISSEMINATION: The trial has obtained approval from the joint CUHK-New Territories East Cluster (CRE-2023.142), and the patient enrolment commenced in July 2023. Written informed consent will be obtained from all participants prior to participation. Study results will be disseminated through publication in peer-reviewed journals and presentations at conference. TRIAL REGISTRATION NUMBER: NCT05799391.

Calcific tendinitis of gluteus maximus insertion.

Calcific tendinitis, classified as enthesopathy, is a self-limiting disease that rarely involves the tendons of the gluteus maximus. We discuss a 52-year-old woman with a 1-year history of localized, reproducible posterolateral pain of her left hip, which was previously treated with steroid injection to her left greater trochanteric bursa without significant pain relief. Plain radiography and magnetic resonance imaging of the left hip revealed abnormal edema and calcifications at the insertion of the gluteus maximus tendon to the gluteal tuberosity, corresponding to the area of maximal tenderness on examination. This case report contributes to the growing medical literature for the rare presentation of calcific tendinitis of gluteus maximus insertion and reinforces the importance of the patient history, focused physical examination with special testing, and pertinent imaging for proper diagnosis and management.

Deciphering the Complexity: Addressing Recurrent Hamstring Injury in a Long-Distance Female Athlete.

Hamstring muscle injuries are prevalent in sports, presenting substantial hurdles for athletes and teams due to their high recurrence rates and prolonged recovery periods. The biceps femoris (BF) muscle is frequently implicated in these injuries, with notably high recurrence rates, particularly at the distal musculotendinous T-junction (DMTJ), where half of BF reinjuries occur. This paper presents a case study of a 31-year-old female long-distance athlete with a history of DMTJ rupture, shedding light on the intricacies associated with hamstring injuries. The case underscores the challenges in accurately interpreting imaging findings, reinforcing the need for clinical-imaging correlation and exploration of lesion mechanisms to achieve an accurate diagnosis, optimize outcomes, and facilitate a safe return to sport.

Prevalence of therapeutic use exemptions at the Olympic Games and Paralympic Games: an analysis of data from 2016 to 2022.

OBJECTIVES: The objectives of this study are to describe the prevalence of therapeutic use exemptions (TUEs) among athletes competing in four Olympic and four Paralympic games. The secondary objective was to present the prohibited substance and methods classes associated with TUEs. METHODS: Data from the Anti-Doping Administration and Management System were extracted for this cross-sectional observation study. Eight cohorts were created to include athletes with TUEs who competed in the Rio 2016, Pyeongchang 2018, Tokyo 2020 and Beijing 2022 Olympic and Paralympic games. Prevalence of TUEs and proportion of prohibited substance and methods classes were defined as percentages among all athletes competing at each games. RESULTS: 28 583 athletes competed in four editions of the Olympic games. Total prevalence of athletes with TUEs was 0.90% among all competitors. At the four Paralympic games, a total of 9852 athletes competed and the total TUE prevalence was 2.76%. The most frequently observed substances associated with TUEs at the Summer Olympics were glucocorticoids (0.50% in Rio) and stimulants (0.39% in Tokyo). At the Summer Paralympics, diuretics (0.79% in Rio) and stimulants (0.75% in Tokyo) were the most common. Winter games had somewhat similar trends, although TUE numbers were very low. CONCLUSIONS: The number of athletes competing with valid TUEs at the Olympic and Paralympic games was <1% and <3%, respectively. Variations in substances and methods associated with TUEs for different medical conditions were identified. Nevertheless, numbers were low, further reaffirming that TUEs are not widespread in elite sport.

Evaluation of surface type and time of day on agility course performance.

Introduction: Canine agility competitions are performed on a variety of surfaces. In the equine and human literature, surface type has been associated with speed, performance, and injury risk. The aim of this study was to evaluate the effect of general surface type and time of day on calculated speed (yards per second over a measured course distance) and course performance during the UKI Agility International (UKI) U.S. Open. We hypothesized that surface type would affect calculated speed, with sand being the slowest. Materials and methods: Data on course performance from the 2021 and 2022 events were obtained directly from UKI. The officiating judge measured course length, automatic timers recorded dogs' course times, and speeds were calculated from these values. Three surfaces (dirt, grass, and sand) were compared across three categories of courses (jumpers, standard, and speedstakes). Differences in calculated speeds and qualifying rates were estimated using generalized estimating equations (GEE) to account for multiple runs by the same handler. Results: Among jumpers courses, those run on sand in 2021 were markedly slower than those run on dirt. Grass and dirt were more similar in terms of average calculated speed, though some courses run on grass were significantly faster than courses run on dirt and vice versa. Time of day effects observed were inconsistent, with more variability observed for dirt and sand than for grass. Discussion: There was a notable variation in calculate speed based on surface with sand being slowest, likely due to the increased energy cost required to run on sand due to its high compliance. Calculated speeds on grass and dirt appeared generally similar, but there was substantial variability of calculated speed among various courses, making comparison of surface effects challenging. Variables within the surface itself (such as compaction level and moisture content) likely play a role in the effects of surface on speed and performance. This study provides insight into the complexity of surface effects on performance in agility dogs and highlights the need for canine-specific surface studies on the effect of surface variables and how these relate to risk of development of musculoskeletal injuries.