Prospective Cohort Study to Investigate Factors Associated With Continued Immobilization of a Nondisplaced Scaphoid Waist Fracture

Purpose: The decision to continue immobilization of a nondisplaced scaphoid waist fracture is often based on radiographic appearance (despite evidence that radiographs are unreliable and inaccurate for diagnosing scaphoid union 6–12 weeks after fracture) and fracture tenderness (even though it is influenced by cognitive biases on pain). This may result in unhelpful additional immobilization. We studied nondisplaced scaphoid waist fractures to determine the factors associated with (1) the surgeon's decision to continue cast or splint immobilization at the first visit when cast removal was being considered; (2) greater pain on examination; and (3) the surgeon's concern about radiographic consolidation. Methods: We prospectively included 46 patients with a nondisplaced scaphoid waist fracture treated nonoperatively. At the first visit when cast removal was considered – after an average of 6 weeks of immobilization – patients rated pain during 4 examination maneuvers. The treating surgeon assessed union on radiographs and decided whether to continue or discontinue immobilization. Patients completed measures of the following: (1) the degree to which pain limits activities (Patient-Reported Outcome Measure Interactive System [PROMIS] Pain Interference Computer Adaptive Test [CAT], Pain Self-Efficacy Questionnaire-2); (2) symptoms of depression (PROMIS Depression CAT); and (3) upper extremity function (PROMIS Upper Extremity Function CAT). We used multivariable regression analysis to investigate the factors associated with each outcome. Results: Perceived inadequate radiographic healing and greater symptoms of depression were independently associated with continued immobilization. Pain during the examination was not associated with continued immobilization. Patient age was associated with pain on examination. Shorter immobilization duration was the only factor associated with the surgeon's perception of inadequate radiographic consolidation. Conclusions: Inadequate radiographic healing and greater symptoms of depression are associated with a surgeon's decision to continue cast or splint immobilization of a nondisplaced scaphoid waist fracture. Clinical relevance: Overreliance on radiographs and inadequate accounting for psychological distress may hinder the adoption of shorter immobilization times for nondisplaced waist fractures.