{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T05:54:53Z","timestamp":1790142893574,"version":"4.0.1"},"reference-count":27,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"11","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,6,4]]},"abstract":"\n Background:<\/jats:title>\n After a lower-extremity fracture, the patient\u2019s priority is to regain function. To date, our ability to measure function has been limited. However, high-fidelity sensors in smartphones continuously measure mobility, providing an expansive pre- and post-injury gait history. We assessed whether pre-injury mobility data, combined with demographic and injury data, reliably predicted post-fracture mobility.<\/jats:p>\n <\/jats:sec>\n \n Methods:<\/jats:title>\n We enrolled 107 adult patients (mean age, 45 years; 43% female, 62% White, 36% Black, 1% Asian, 1% more than one race) \u22656 months after the surgical treatment of a lower-extremity fracture. Consenting patients exported their Apple iPhone mobility metrics, including step count, walking speed, step length, walking asymmetry, and double-support time. We integrated these mobility measures with demographic and injury data. Using nonlinear modeling, we assessed whether pre-injury mobility metrics combined with baseline data predicted post-fracture mobility.<\/jats:p>\n <\/jats:sec>\n \n Results:<\/jats:title>\n \n All models were well calibrated and had model fits ranging from an adjusted R\n 2<\/jats:sup>\n of 0.18 (walking asymmetry) to 0.61 (double-support time). Pre-injury function strongly predicted post-injury mobility in all models. After the injury, the average daily step count increased by 65 steps each week (95% confidence interval [CI], 56 to 75). Weekly gains were significantly greater within 6 weeks after the injury (92 daily steps per week; 95% CI, 58 to 127) than 20 to 26 weeks post-injury (19 daily steps per week; 95% CI, 11 to 27; p < 0.001). Greater pre-injury steps were associated with increased post-injury mobility (301 daily steps post-injury per 1,000 steps pre-injury; 95% CI, 235 to 367). Mean walking speed declined by 0.200 m\/s (95% CI, \u22120.257 to \u22120.143) from injury to 8 weeks post-injury. From 12 to 26 weeks post-injury, the average walking speed increased by 0.071 m\/s (95% CI, 0.044 to 0.097).\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions:<\/jats:title>\n These proof-of-concept findings highlight the value of high-fidelity pre-injury mobility data in predicting recovery. Individualized recovery projections can provide patient-friendly counseling tools and useful clinical insight for surgeons.<\/jats:p>\n <\/jats:sec>\n \n Level of Evidence:<\/jats:title>\n \n Prognostic\n Level III<\/jats:underline>\n . See Instructions for Authors for a complete description of levels of evidence.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.2106\/jbjs.24.01305","type":"journal-article","created":{"date-parts":[[2025,4,28]],"date-time":"2025-04-28T14:00:43Z","timestamp":1745848843000},"page":"e57","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":4,"title":["Predicting Post-Fracture Recovery with Smartphone Mobility Data"],"prefix":"10.2106","volume":"107","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0470-0330","authenticated-orcid":false,"given":"Brian M.","family":"Shear","sequence":"first","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8685-5373","authenticated-orcid":false,"given":"Dane J.","family":"Brodke","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6313-006X","authenticated-orcid":false,"given":"Gregory R.","family":"Hancock","sequence":"additional","affiliation":[{"name":"Department of Human Development and Quantitative Methodology, University of Maryland College of Education, College Park, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8974-1988","authenticated-orcid":false,"given":"Patrick","family":"McGlone","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Surgery, Walter Reed National Military Medical Center, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8977-1191","authenticated-orcid":false,"given":"Haley","family":"Demyanovich","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vivian","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alice","family":"Bell","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1424-4458","authenticated-orcid":false,"given":"David","family":"Okhuereigbe","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9111-9239","authenticated-orcid":false,"given":"Gerard P.","family":"Slobogean","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5628-6584","authenticated-orcid":false,"given":"Robert V.","family":"O\u2019Toole","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nathan N.","family":"O\u2019Hara","sequence":"additional","affiliation":[{"name":"Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2025,4,28]]},"reference":[{"key":"bib1-20260205","doi-asserted-by":"crossref","first-page":"21514593241236647","DOI":"10.1177\/21514593241236647","article-title":"Fix or replace? 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