{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T16:14:28Z","timestamp":1789661668241,"version":"4.0.1"},"reference-count":38,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:00:00Z","timestamp":1786665600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["beva.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Equine Veterinary Journal"],"abstract":"Abstract<\/jats:title>\n \n Background<\/jats:title>\n \n Back pain and poor performance in horses are difficult to assess objectively and thoracolumbar flexion\u2010extension range of motion (FE\n ROM<\/jats:sub>\n ) is not reliably evaluated by subjective observation alone. A handheld, smartphone\u2010based markerless computer vision system (RealHorse\u00ae; RH) may enable objective clinical and field\u2010based FE\n ROM<\/jats:sub>\n assessment but requires validation against an established optical motion capture reference system (Qualisys\u00ae; QS).\n <\/jats:p>\n <\/jats:sec>\n \n Objectives<\/jats:title>\n \n To compare the accuracy and precision of RH relative to QS for measuring FE\n ROM<\/jats:sub>\n in horses trotting on a straight line and on a circle.\n <\/jats:p>\n <\/jats:sec>\n \n Study Design<\/jats:title>\n Cross\u2010sectional comparative validation study.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n Fifty\u2010nine horses were recorded trotting on a straight line; 23 of these were also recorded on a circle. Data were collected simultaneously using RH and QS, with a light source for manual frame\u2010level synchronisation. The validation videos of horses were not used to train the RH algorithm. Agreement between RH and QS was analysed separately for straight\u2010line and circular trot at stride and trial levels using mean signed error (MSE), mean absolute error (MAE), and Bland\u2013Altman limits of agreement (LoA).<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n On the straight\u2010line, stride\u2010level MSE was \u22120.08\u00b0, MAE 0.96\u00b0, and LoA \u22122.49\u00b0 to 2.32\u00b0. Trial\u2010level agreement was high, with MSE \u22120.13\u00b0, MAE 0.44\u00b0, and LoA \u22121.22\u00b0 to 0.94\u00b0. On the circle, stride\u2010level MSE was \u22120.71\u00b0, MAE 1.14\u00b0, and LoA \u22123.17\u00b0 to 1.74\u00b0. At the trial\u2010level, variability was moderate (MSE \u22120.62\u00b0, MAE 0.78\u00b0, LoA \u22122.18\u00b0 to 0.93\u00b0). Overall agreement was lower on the circle than on the straight\u2010line and higher at trial\u2010level than at stride\u2010level.<\/jats:p>\n <\/jats:sec>\n \n Conclusions<\/jats:title>\n Clinically, RH may support objective clinic and field\u2010based monitoring of thoracolumbar flexion\u2010extension range of motion, especially for repeated within\u2010horse assessments, but decision thresholds remain to be established. Stride\u2010level agreement between RH and QS was influenced by expected stride\u2010to\u2010stride variability, whereas averaging across strides improved agreement at the trial\u2010level.<\/jats:p>\n <\/jats:sec>","DOI":"10.1002\/evj.70310","type":"journal-article","created":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T09:53:06Z","timestamp":1786701186000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Validation of a handheld smartphone markerless method for quantifying thoracolumbar flexion\u2013extension range of motion in horses at trot"],"prefix":"10.1002","author":[{"given":"Maria Rosendahl","family":"Christensen","sequence":"first","affiliation":[{"name":"iKeyVet Fredensborg Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jakob","family":"Kirkegaard","sequence":"additional","affiliation":[{"name":"Keydiagnostics (RealHorse\u00ae) Fredensborg Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katja","family":"Berg","sequence":"additional","affiliation":[{"name":"Keydiagnostics (RealHorse\u00ae) Fredensborg Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristian Ringkj\u00e6r","family":"Andresen","sequence":"additional","affiliation":[{"name":"iKeyVet Fredensborg Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4227-9890","authenticated-orcid":false,"given":"Sabrina","family":"Skov Hansen","sequence":"additional","affiliation":[{"name":"Department of Veterinary Clinical Sciences University of Copenhagen Copenhagen Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-4678-2316","authenticated-orcid":false,"given":"Karsten","family":"Key","sequence":"additional","affiliation":[{"name":"Keydiagnostics (RealHorse\u00ae) Fredensborg Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,8,14]]},"reference":[{"key":"e_1_2_14_2_1","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1111\/j.2042-3306.1982.tb02366.x","article-title":"Effect of induced back pain on gait and performance of trotting horses","volume":"14","author":"Jeffcott LB","year":"1982","journal-title":"Equine Vet J"},{"key":"e_1_2_14_3_1","doi-asserted-by":"crossref","first-page":"707","DOI":"10.2746\/0425164044848226","article-title":"Kinematic evaluation of the back in the sport horse with back pain","volume":"36","author":"Wennerstrand J","year":"2004","journal-title":"Equine Vet J"},{"key":"e_1_2_14_4_1","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/j.tvjl.2017.03.009","article-title":"Alterations in thoracolumbosacral movement when pain causing lameness has been improved by diagnostic analgesia","volume":"224","author":"Greve L","year":"2017","journal-title":"Vet J"},{"key":"e_1_2_14_5_1","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.tvjl.2017.01.003","article-title":"Thoracolumbar movement in sound horses trotting in straight lines in hand and on the lunge and the relationship with hind limb symmetry or asymmetry","volume":"220","author":"Greve L","year":"2017","journal-title":"Vet J"},{"key":"e_1_2_14_6_1","doi-asserted-by":"crossref","first-page":"1112","DOI":"10.1111\/evj.13906","article-title":"Adaptations in equine axial movement and muscle activity occur during induced fore\u2010 and hindlimb lameness: a kinematic and electromyographic evaluation during in\u2010hand trot","volume":"55","author":"Spoormakers TJP","year":"2023","journal-title":"Equine Vet J"},{"key":"e_1_2_14_7_1","doi-asserted-by":"crossref","first-page":"130","DOI":"10.2746\/042516408X345099","article-title":"Osteoarthritis of the thoracolumbar synovial intervertebral articulations: clinical and radiographic features in 77 horses with poor performance and back pain","volume":"41","author":"Girodroux M","year":"2009","journal-title":"Equine Vet J"},{"key":"e_1_2_14_8_1","doi-asserted-by":"crossref","DOI":"10.3390\/s23249625","article-title":"A method for quantifying back flexion\/extension from three inertial measurement units mounted on a horse's withers, thoracolumbar region, and pelvis","volume":"23","author":"Hatrisse C","year":"2023","journal-title":"Sensors (Basel, Switzerland)"},{"key":"e_1_2_14_9_1","doi-asserted-by":"crossref","first-page":"280","DOI":"10.2746\/042516409X394454","article-title":"Basic kinematics of the saddle and rider in high\u2010level dressage horses trotting on a treadmill","volume":"41","author":"Bystr\u00f6m A","year":"2009","journal-title":"Equine Vet J"},{"key":"e_1_2_14_10_1","doi-asserted-by":"crossref","first-page":"495","DOI":"10.2746\/0425164044877431","article-title":"Kinematic evaluation of the back in fully functioning riding horses","volume":"36","author":"Johnston C","year":"2004","journal-title":"Equine Vet J"},{"key":"e_1_2_14_11_1","doi-asserted-by":"crossref","first-page":"210","DOI":"10.1111\/j.2042-3306.1999.tb05219.x","article-title":"Kinematics of the equine back: flexion\u2010extension movements in sound trotting horses","volume":"31","author":"Audigi\u00e9 F","year":"1999","journal-title":"Equine Vet J"},{"key":"e_1_2_14_12_1","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0222822","article-title":"Range of motion and between\u2010measurement variation of spinal kinematics in sound horses at trot on the straight line and on the lunge","volume":"15","author":"Hardeman AM","year":"2020","journal-title":"PLoS One"},{"key":"e_1_2_14_13_1","doi-asserted-by":"crossref","first-page":"92","DOI":"10.2746\/042516409X479568","article-title":"Repeatability of subjective evaluation of lameness in horses","volume":"42","author":"Keegan KG","year":"2010","journal-title":"Equine Vet J"},{"key":"e_1_2_14_14_1","doi-asserted-by":"crossref","first-page":"112","DOI":"10.2746\/042516408X343000","article-title":"Evidence of the development of \u2018domain\u2010restricted\u2019 expertise in the recognition of asymmetric motion characteristics of hindlimb lameness in the horse","volume":"41","author":"Parkes RSV","year":"2009","journal-title":"Equine Vet J"},{"issue":"1","key":"e_1_2_14_15_1","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1111\/evj.14516","article-title":"Agreement between subjective gait assessment and markerless video gait\u2010analysis in endurance horses","volume":"58","author":"De Chiara M","year":"2025","journal-title":"Equine Vet J"},{"key":"e_1_2_14_16_1","doi-asserted-by":"crossref","DOI":"10.3390\/s23146301","article-title":"Inertial sensor technologies\u2014their role in equine gait analysis, a review","volume":"23","author":"Crecan CM","year":"2023","journal-title":"Sensors (Basel, Switzerland)"},{"key":"e_1_2_14_17_1","doi-asserted-by":"crossref","first-page":"813","DOI":"10.1111\/evj.13076","article-title":"Research trends in equine movement analysis, future opportunities and potential barriers in the digital age: a scoping review from 1978 to 2018","volume":"51","author":"Egan S","year":"2019","journal-title":"Equine Vet J"},{"key":"e_1_2_14_18_1","doi-asserted-by":"crossref","first-page":"757","DOI":"10.2460\/ajvr.2001.62.757","article-title":"Basic three\u2010dimensional kinematics of the vertebral column of horses trotting on a treadmill","volume":"62","author":"Faber M","year":"2001","journal-title":"Am J Vet Res"},{"key":"e_1_2_14_19_1","doi-asserted-by":"crossref","first-page":"235","DOI":"10.2746\/042516402776186010","article-title":"Repeatability of back kinematics in horses during treadmill locomotion","volume":"34","author":"Faber M","year":"2002","journal-title":"Equine Vet J"},{"key":"e_1_2_14_20_1","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1111\/j.2042-3306.2010.00200.x","article-title":"Inertial sensors for assessment of back movement in horses during locomotion over ground","volume":"42","author":"Warner SM","year":"2010","journal-title":"Equine Vet J"},{"key":"e_1_2_14_21_1","doi-asserted-by":"crossref","DOI":"10.3390\/s18030850","article-title":"EquiMoves: a wireless networked inertial measurement system for objective examination of horse gait","volume":"18","author":"Bosch S","year":"2018","journal-title":"Sensors (Basel, Switzerland)"},{"key":"e_1_2_14_22_1","doi-asserted-by":"crossref","first-page":"153","DOI":"10.2746\/042516408X250292","article-title":"Effect of chiropractic manipulations on the kinematics of back and limbs in horses with clinically diagnosed back problems","volume":"40","author":"G\u00f3mez \u00c1lvarez CB","year":"2008","journal-title":"Equine Vet J"},{"key":"e_1_2_14_23_1","doi-asserted-by":"crossref","first-page":"448","DOI":"10.3415\/VCOT-08-09-0088","article-title":"Spinal kinematics in horses with induced back pain","volume":"22","author":"Wennerstrand J","year":"2009","journal-title":"Vet Comp Orthop Traumatol"},{"key":"e_1_2_14_24_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41746-020-00376-2","article-title":"Deep learning\u2010enabled medical computer vision","volume":"4","author":"Esteva A","year":"2021","journal-title":"NPJ Digit Med"},{"key":"e_1_2_14_25_1","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1038\/s41592-018-0234-5","article-title":"Fast animal pose estimation using deep neural networks","volume":"16","author":"Pereira TD","year":"2019","journal-title":"Nat Methods"},{"key":"e_1_2_14_26_1","doi-asserted-by":"publisher","DOI":"10.1002\/vms3.70739"},{"key":"e_1_2_14_27_1","doi-asserted-by":"publisher","DOI":"10.1111\/evj.70109"},{"key":"e_1_2_14_28_1","doi-asserted-by":"publisher","DOI":"10.1002\/evj.70149"},{"key":"e_1_2_14_29_1","doi-asserted-by":"crossref","first-page":"976","DOI":"10.1145\/3412841.3441973","volume-title":"Proceedings of the 36th annual ACM symposium on applied computing","author":"Wang Y","year":"2021"},{"key":"e_1_2_14_30_1","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1111\/j.2042-3306.2002.tb05439.x","article-title":"Effect of conformational aspects on the movement of the equine back","volume":"34","author":"Johnston C","year":"2002","journal-title":"Equine Vet J"},{"key":"e_1_2_14_31_1","doi-asserted-by":"crossref","DOI":"10.1016\/j.bspc.2019.101674","article-title":"Quantitative lameness assessment in the horse based on upper body movement symmetry: the effect of different filtering techniques on the quantification of motion symmetry","volume":"57","author":"Serra Bragan\u00e7a FM","year":"2020","journal-title":"Biomed Signal Process Control"},{"key":"e_1_2_14_32_1","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1111\/evj.12446","article-title":"Head and pelvic movement asymmetry during lungeing in horses with symmetrical movement on the straight","volume":"48","author":"Rhodin M","year":"2016","journal-title":"Equine Vet J"},{"key":"e_1_2_14_33_1","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1111\/j.2042-3306.2006.tb05588.x","article-title":"Head and body centre of mass movement in horses trotting on a circular path","volume":"38","author":"Clayton HM","year":"2006","journal-title":"Equine Vet J"},{"key":"e_1_2_14_34_1","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/S0140-6736(86)90837-8","article-title":"Statistical methods for assessing agreement between two methods of clinical measurement","volume":"1","author":"Bland JM","year":"1986","journal-title":"Lancet"},{"key":"e_1_2_14_35_1","doi-asserted-by":"crossref","first-page":"571","DOI":"10.1080\/10543400701329422","article-title":"Agreement between methods of measurement with multiple observations per individual","volume":"17","author":"Bland JM","year":"2007","journal-title":"J Biopharm Stat"},{"key":"e_1_2_14_36_1","doi-asserted-by":"crossref","first-page":"337","DOI":"10.1016\/0010-4825(90)90013-F","article-title":"A note on the use of the intraclass correlation coefficient in the evaluation of agreement between two methods of measurement","volume":"20","author":"Bland JM","year":"1990","journal-title":"Comput Biol Med"},{"key":"e_1_2_14_37_1","doi-asserted-by":"crossref","first-page":"141","DOI":"10.11613\/BM.2015.015","article-title":"Understanding Bland Altman analysis","volume":"25","author":"Giavarina D","year":"2015","journal-title":"Biochem Med (Zagreb)"},{"key":"e_1_2_14_38_1","doi-asserted-by":"crossref","first-page":"818","DOI":"10.1111\/evj.12844","article-title":"Vertical movement symmetry of the withers in horses with induced forelimb and hindlimb lameness at trot","volume":"50","author":"Rhodin M","year":"2018","journal-title":"Equine Vet J"},{"key":"e_1_2_14_39_1","doi-asserted-by":"crossref","first-page":"301","DOI":"10.2460\/ajvr.2001.62.301","article-title":"Methodology and validity of assessing kinematics of the thoracolumbar vertebral column in horses on the basis of skin\u2010fixated markers","volume":"62","author":"Faber M","year":"2001","journal-title":"Am J Vet Res"}],"container-title":["Equine Veterinary Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/beva.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/evj.70310","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/beva.onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/evj.70310","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/beva.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/evj.70310","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T09:53:10Z","timestamp":1786701190000},"score":1,"resource":{"primary":{"URL":"https:\/\/beva.onlinelibrary.wiley.com\/doi\/10.1002\/evj.70310"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,14]]},"references-count":38,"alternative-id":["10.1002\/evj.70310"],"URL":"https:\/\/doi.org\/10.1002\/evj.70310","archive":["Portico"],"relation":{},"ISSN":["0425-1644","2042-3306"],"issn-type":[{"value":"0425-1644","type":"print"},{"value":"2042-3306","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,14]]},"assertion":[{"value":"2026-01-28","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-30","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-08-14","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"evj.70310"}}