Factors associated with surgeon recommendation for additional cast immobilization of a CT-verified nondisplaced scaphoid waist fracture
Authors: Bulstra Anne Eva J. , Crijns Tom J. , Janssen Stein J. , Buijze Geert A. , Ring David , Jaarsma Ruurd L. , Kerkhoffs Gino M. M. J. , Obdeijn Miryam C. , Doornberg Job N. ,   The Science of Variation Group, Peters A. , Spoor A. B. , Shrivastava Abhay , Chauhan Aakash , Shafritz Adam , Ilyas Asif M. , Vochteloo Anne J. H. , Powell Andrew John , Castillo Alberto Pérez , Godoy-Santos Alexandre Leme , Gelvez Amparo Gomez , Bauer Andrea , Barquet Antonio , Kristan Anze , Prkic Ante , Jubel Axel , Mirck Boj , Kreis B. E. , Bamberger H. Brent , Belangero William Dias , Hearon Bernard F. , Palmer Bradley , Hyatt Brad , Wills Brian P. D. , Broekhuyse Henry , Buckley Richard , Altintas Burak , Campbell Sean T. , Ekholm Carl , Fernandes Carlos Henrique , Fernandes C. H. , Weiss Carl , Garnavos Christos , Metzger Charles , Wilson Christopher J. , Bainbridge Chris , Deml Christian , Moreta Jesus , Kleweno Conor , Moreno-Serrano Constanza L. , Ordway Craig B. , Klostermann Cyrus , Zeltser David , Dennison David G. , Verbeek Diederik O. , Polatsch Dan , Barreto Camilo Jose Romero , Kabir Koroush , Shafi Mohamed , Patiño Juan M. , van Riet Roger , Sodha Samir , Duncan Scott , Wascher Daniel C. , Ibrahim Edward F. , Ballas Efstathios G. , Harvey Edward , Rodriguez Edward K. , Pemovska Emilia Stojkovska , Walbeehm E. , Evans Peter J. , Zaidenberg Ezequiel E. , O’Brien Fred , Seibert Franz Josef , Bloemers Frank W. , Caro Gladys Cecilia Zambrano , DeSilva Gregory , Babis George , Pianka George , Githens Michael , Veríssimo Giselly Miranda , Garrigues Grant E. , Fierro Guido , Durchholz Holger , Hall Jeremy , McCutchan Hal , Nancollas Michael , Young Colby , Watchmaker Greg P. , Pess Gary M. , Lane Lewis B. , Villamizar Harold Alonso , Pountos Ippokratis , Kimball Hervey L. , Hofmeister Eric P. , McGraw Iain , Erol Konul , Di Giovanni J.F. , Brubacher Jacob W. , Biert Jan , Fanuele Jason C. , Tavakolian Jason D. , Choueka Jack , Ribeiro Jose Eduardo Grandi , Filho Jose Eduardo Grandi Ribeiro , Conflitti Joseph M. , Roiz J. M. R , Munyak John , Nappi James F. , Doornberg Job N. , Erickson John M. , Boretto Jorge G. , Post Joel M. , Rubio Jorge , Scolaro John A. , Taras John , Domenech Julio , Sandoval Julio , Wint Jeffrey , Faust Katherine Celeste , Butters Ken , Jeray Kyle , Prommersberger Karl-Josef , Ozer Kagan , Kraan G. A. , Chepla Kyle J. , Poelhekke L. M. S. J. , Mica Ladislav , Weiss Lawrence , Adolfsson Lars , Borris Lars C. , Grandizio Louis Christopher , Elmans Leon , Náquira Escobar Luis Felipe , van der Plaat L. W. , Verhofstad M. , Sanmartin-Fernandez Marcos , Di Micoli Mario , Kastelec Matej , Calcagni Maurizio , Talbot Max , Bronkhorst Maarten W. G. A. , McAuliffe John A. , Behrman Michael , Quell M. , Nakashian Michael , Patel Minoo , Bengard Matthew , Palmer M. Jason , Prayson Michael , Knobe Matthias , Pirpiris Marinis , Tyllianakis Minos , Grafe Michael W. , Chen Neal , Elias Nelson , Akabudike Ngozi M. , Hoekzema Nathan A. , Shortt Nicholas L. , Kanakaris Nikolaos , Kazmers Nikolas H. , Lightdale-Miric Nina , Calandruccio Jim , Brink Ole , Richardson Martin , Ortiz Jr Jose A. , Hannemann Pascal F. W. , van Eerten P. V. , Inna Prashanth , Althausen Peter , Lygdas Panagiotis , Parnes Nata , Martineau Paul A. , Benhaim Prosper , Forno Philip , Choudhari Pradeep , Hahn Peter , Townsend Peter Fedele , Giannoudis Peter , Guidera Paul , Muhl Philipp , Streubel Philipp , Jebson Peter , Owens Patrick W. , Pritsch Tamir , Scibetta Paul J. , Nelissen Rob , Haverlag Robert , van Leerdam R. H. , de Bedout Ramon , Rowinski Sergio , Draeger Reid W. , Fricker R. , Wallensten Richard , Gilbert Richard S. , Rizzo Marco , Jenkinson Richard , Van Demark Jr Robert E. , Rodner Craig , Rohde Rachel S. M. D. , Page Richard S. , Ruch David , Sabesan Vani J. , Kennedy Stephen A. , Schep Niels W. L. , Mitchell Scott , Farr Sebastian , Sibley Paul A. D. O. , Kaar Scott G. , Meylaerts S. A. , Henry Steven L. , Meletiou Steven , Morgan Steven J. , Swiontkowski Marc , Schepers T. , DeCoster Thomas , Baxamusa Taizoon , Kaplan F. Thomas D. , Begue Thierry , Mittlmeier Thomas , Rebele Thomas , Apard T , Chesser Tim , Havlifçek Tomo , Rozental T. , Tosounidis Theodoros , Utkan Aydin H. , Giordano Vincenzo , Gajendran Varun Kashyap , Nikolaou Vasileios S. , Ruggiero Vincent , Hammert Warren C. , Weil Yoram , Satora Wojciech , Balogh Zsolt 
Published: July 2021

Abstract
Introduction
Data from clinical trials suggest that CT-confirmed nondisplaced scaphoid waist fractures heal with less than the conventional 8–12 weeks of immobilization. Barriers to adopting shorter immobilization times in clinical practice may include a strong influence of fracture tenderness and radiographic appearance on decision-making. This study aimed to investigate (1) the degree to which surgeons use fracture tenderness and radiographic appearance of union, among other factors, to decide whether or not to recommend additional cast immobilization after 8 or 12 weeks of immobilization; (2) identify surgeon factors associated with the decision to continue cast immobilization after 8 or 12 weeks.

Materials and methods
In a survey-based study, 218 surgeons reviewed 16 patient scenarios of CT-confirmed nondisplaced waist fractures treated with cast immobilization for 8 or 12 weeks and recommended for or against additional cast immobilization. Clinical variables included patient sex, age, a description of radiographic fracture consolidation, fracture tenderness and duration of cast immobilization completed (8 versus 12 weeks). To assess the impact of clinical factors on recommendation to continue immobilization we calculated posterior probabilities and determined variable importance using a random forest algorithm. Multilevel logistic mixed regression analysis was used to identify surgeon characteristics associated with recommendation for additional cast immobilization.

Results
Unclear fracture healing on radiographs, fracture tenderness and 8 (versus 12) weeks of completed cast immobilization were the most important factors influencing surgeons’ decision to recommend continued cast immobilization. Women surgeons (OR 2.96; 95% CI 1.28–6.81, p  =  0.011), surgeons not specialized in orthopedic trauma, hand and wrist or shoulder and elbow surgery (categorized as ‘other’) (OR 2.64; 95% CI 1.31–5.33, p  =  0.007) and surgeons practicing in the United States (OR 6.53, 95% CI 2.18–19.52, p  =  0.01 versus Europe) were more likely to recommend continued immobilization.

Conclusion
Adoption of shorter immobilization times for CT-confirmed nondisplaced scaphoid waist fractures may be hindered by surgeon attention to fracture tenderness and radiographic appearance.