CORR Insights®: Comparing Open and Arthroscopic Grafting for Scaphoid Nonunion: Is There Truly a Noticeable Difference?

Where Are We Now? Scaphoid fractures are the most common carpal bone injuries, and they are associated with a high risk of symptomatic nonunion when not treated in a timely fashion. They can subsequently progress into symptomatic arthritis if not addressed appropriately. Having said that, scaphoid nonunion management remains a challenge with no clear consensus on treatment. Surgical repair frequently relies on some form of bone grafting and fixation, which can be achieved through a variety of strategies that depend on surgeon experience and preferences, including open or arthroscopic approaches, free or vascularized bone grafts, a choice of fixation devices, various postoperative management protocols, and other considerations. Although open grafting offers direct visualization and has a long track record, surgeons who prefer arthroscopy appreciate the augmented ability to look beyond the fracture, to identify other ligamentous injuries that would otherwise be missed, and express concerns about the insult to the surrounding ligaments that threatens an already poor vascular supply. On the other hand, arthroscopic management is technically challenging and requires mastery of advanced arthroscopic techniques as well as the willingness to accept surgical times that generally are longer than would be needed with open approaches. With this background in mind, the study by Eravsar et al. [3], published in this issue of Clinical Orthopaedics and Related Research®, addresses the question of whether arthroscopic management leads to better functional and/or objective outcomes than open procedures through a retrospective review of patients with a minimum of 1 year of follow-up. The authors, who have extensive experience in scaphoid nonunion management (141 cases over 10 years), found no meaningful differences in functional outcomes and objective measures between arthroscopic and open bone grafting at both the 1-year and 2-year follow-up visits. They concluded that the ability to identify and address concomitant intraarticular pathologies did not seem to affect outcomes. Where Do We Need To Go? This findings of this article invite the following simple question: Is arthroscopic management worth the trouble? Adding layers of complexity and pursuing interventions that do not seem to contribute to improved patient outcomes yet are likely to increase costs (direct, indirect, and societal) may not be in the best interest of patients, healthcare systems, and communities at large. The identification of pathology does not necessarily indicate that it occurred as a direct effect of a recent injury (that is, at the time of the scaphoid fracture), nor does it substantiate that it contributes to patient symptoms in a meaningful way. One major matter to be considered is the value added by arthroscopic interventions that address findings that may never cause symptoms. Such incidental findings are so common in radiology studies that they earned the nickname "incidentaloma" [1]. The prevalence of asymptomatic findings observed incidentally in wrists is well known. One such example is asymptomatic triangular fibrocartilage complex (TFCC) tears, the incidence of which increases with age. A 2012 MRI study of 103 asymptomatic patients identified TFCC tears in 22% of participants—again, all patients were asymptomatic [5]—which is slightly more than the 19% (6 of 31) of TFCC tears identified and debrided in the article. This finding makes an argument that sometimes arthroscopy leads to "surgery of opportunity": performing surgery simply because the surgeon happened to come across an incidental finding that, if left untreated, never would have resulted in symptoms. It would be interesting if future studies demonstrate the development of symptoms when incidental arthroscopic findings are left untreated. Another concern is related to the "law of the instrument," a form of cognitive bias commonly known as Maslow's Hammer or the Golden Hammer [10], which describes the tendency to overuse a familiar (or favorite) tool. This phenomenon was described by Abraham Maslow who wrote in 1966, "If the only tool you have is a hammer, it is tempting to treat everything as if it were a nail [4]." For these reasons, it is imperative to distinguish the true value of what we do from the selling points that we rely on to justify what we do. Do we truly know that open exposure of scaphoids jeopardizes their vascularity? If so, does that affect union rate or delay recovery? Do we truly know that open exposure through the wrist capsule compromises mechanics, proprioception, and neuromuscular control in a consequential way? Future studies need to help us answer these questions. How Do We Get There? Looking at the effect of open versus arthroscopic exposure on scaphoid vascularity and healing and wrist mechanics can be particularly challenging because of the numerous factors involved in the care of those injuries and their outcomes. Many of those factors are patient-, fracture-, and surgeon-specific, which makes prospective or randomized control trials difficult to execute without massive investment in funding and effort. To have a meaningful comparison, a surgeon or group of surgeons who are established experts in open and arthroscopic management of scaphoid fractures should investigate outcomes prospectively, thus eliminating the effect of the learning curve and the use of historic data, which can skew the conclusions. We can revisit the vascular supply of the scaphoid with the above concerns in mind. We could assess perfusion of native scaphoids and compare dorsal, volar, and arthroscopic approaches on blood flow to the proximal pole using micro-CT [6]. This would involve injecting specimens with a contrast agent after exposure, extracting the scaphoids, and scanning them using a micro-CT scanner. A more clinically oriented evaluation could be done noninvasively with the help of laser-Doppler flowmetry and spectrophotometry, which has been used to assess scaphoid microcirculation previously [9]. Regarding the mechanics after exposure, this study may be challenging to perform in a basic science setting as we do not have good models of healed capsulotomies. Read This Next Readers who are interested in learning more about cognitive bias and its relationship to surgical outcomes and safety are encouraged to read this systematic review [2]. Although this review does not specifically address the law of the instrument in particular, it does demonstrate how our own biases affect our performance and our patients' well-being and can have negative impact across all points of surgical care. In another take on cognitive bias, the authors view it as a "shortcut" that we apply subconsciously to new scenarios to simplify decision-making [8]. The authors specifically defined specialty bias as an observation that physicians are more likely to favor treatments within their scope of practice. This point may be particularly relevant to this article, as advanced arthroscopists are the ones who highlight the benefits of arthroscopic interventions compared with open techniques and emphasize the theoretical downsides of the latter. Such bias can lead to unnecessary interventions. For a broader review of recent technical and technological developments in wrist arthroscopy, this article describes the current and most recent advances in bone grafting for scaphoid nonunion, transosseous repair and reconstruction of the TFCC, and reconstruction of the scapholunate and lunotriquetral ligaments [7]. For a glimpse of the future, this article suggested the use of robot‐assisted fixation that uses three‐dimensional intraoperative real‐time image navigation in conjunction with wrist arthroscopy for the treatment of scaphoid nonunions [11].