Abstract
Background:
Temporary management of closed trimalleolar ankle fractures may involve closed reduction and splint application vs external fixation (ex-fix). One of the primary concerns of using splinting is loss of reduction and soft tissue compromise. The objective of this study was to determine if there is a clinically significant difference in short-term soft tissue complications (STCs) in patients with trimalleolar or trimalleolar-equivalent ankle fractures treated with temporary closed reduction and splinting vs ex-fix.
Methods:
In this multicenter retrospective review from 2 level 1 trauma centers, patients with closed trimalleolar ankle fractures treated surgically from 2017 to 2022 were identified. Demographic data, surgical details, radiographic data, and postoperative details were reviewed and collected to determine postoperative soft tissue complications.
Results:
Overall, 488 patients met inclusion criteria; 395 patients (80.9%) were managed with temporary splinting and 93 with ex-fix (19.1%). Median follow-up was 24 weeks (range 8-292). The cohort’s STC rate was 8.4% (41 of 488), including 2.9% (14 of 488) that required reoperation and 5.5% (27 of 488) that required nonoperative treatment. STC occurred in 6 of 93 ex-fix patients (6.5%) and 35 of 395 temporary splinting patients (8.9%) (risk difference −2.4% [95% CI −7.1% to 4.9%]; OR 0.70 [95% CI 0.28-1.74]; P = .45). Reoperation for STC occurred in 3 of 93 ex-fix patients (3.2%) and 11 of 395 temporary splinting patients (2.8%) (risk difference 0.4% [95% CI −2.5% to 6.4%]; OR 1.16 [95% CI 0.31-4.25]; P = .73).
Conclusion:
The results suggest similar rates of STC with ex-fix and temporary splinting before definitive fixation of ankle fractures with a posterior malleolus component. Surgeons must consider if there is a benefit to use ex-fix, considering the additional cost and burden to patients.
This is a visual representation of the abstract.
Introduction
Ankle fracture dislocations are injuries that are commonly encountered by the orthopaedic surgeon.1,8,14 These injuries require prompt closed reduction and splinting to restore the relationship of normal anatomy, limit pressure and tension on the soft tissue envelope, decrease pressure on the cartilage, and allow perfusion to the foot.5,6,13 Following an adequate closed reduction and splint application of closed injuries, multiple pathways exist between a closed reduction and definitive surgical treatment of the ankle fracture. 11 Patients may undergo immediate or delayed definitive fixation. In the case of the latter, a decision must be made regarding maintenance of the ankle reduction in a splint prior to definitive fixation vs temporary ankle-spanning external fixation (ex-fix). Both methods have been accepted, with proponents of each tactic.
Some surgeons use ex-fix for multiple reasons, including concern for instability, better evaluation of soft tissues, and presence of neuropathy and/or obesity. Loss of reduction in a splint may predispose patients to a higher risk of skin necrosis from pressure wounds and to a delay to definitive fixation. 4 Certain fracture features may be more concerning for instability, such as trimalleolar fracture patterns with larger posterior malleolus fragments. 9 Skin conditions are more easily evaluated and exposed in an external fixator vs a splint. Concern regarding patient compliance in a splint may be alleviated, although not eliminated, with ex-fix.
Other surgeons may almost exclusively maintain splints following closed reduction until the time of definitive fixation and reserve ex-fix for irreducible ankles with poor soft tissue envelopes not amenable to immediate definitive fixation or other unstable fracture characteristics. This practice requires skilled providers in the emergency room setting to reduce and apply appropriately molded splints or casts. Potential advantages of this treatment algorithm include the reduced burden of additional surgery for ex-fix and elimination of potential complications of pin site infections and fractures around pin sites. 2
Several small retrospective studies have been published on the topic of evaluating redislocations and complications in ankle fractures managed with temporary splinting vs ex-fix.4,9,15 There is a lack of consensus and evidence to support the use of ex-fix for temporary immobilization of ankle fractures that may otherwise be adequately treated in a splint. This multicenter retrospective cohort study between two level 1 trauma centers had the primary objective of determining if there is a difference in short-term soft tissue complications in patients with trimalleolar or trimalleolar-equivalent ankle fractures treated with temporary closed reduction and splinting vs ex-fix. Secondary objectives included evaluating redislocation rates, pin site–related complications, and other predictors of soft tissue complications. The hypothesis was that there is no clinically significant difference in the rate of soft tissue complications or the need for additional surgery to manage soft tissue complications between patients treated with temporary splinting vs ex-fix. The goal of the study was to further guide management of these injuries and possibly avoid unnecessary ex-fix events.
Methods
Institutional Review Board approval for this retrospective review was obtained at both participating centers; due to the nature of the study, the requirement for participant consent was waived. Current Procedural Terminology (CPT) codes (27769, 27822, 27823, 27827, and 27828) were utilized to identify patients treated between January 2017 through January 2023 for ankle fractures of interest at two level 1 trauma tertiary care centers. A prospective fracture registry at one center was also utilized to extract patients with fractures of interest. Radiographs were reviewed and classified according to the AO Foundation/Orthopaedic Trauma Association (AO/OTA) classification system. 12 The following classifications were included: 44-B3.1, 44-B3.2, 44-B3.3, 44-C1.3, 44-C2.3, and 44-C3.3. These fracture patterns represent rotational ankle fractures with a posterior malleolus component, including Maisonneuve-type injuries.
Medical records were reviewed for demographic, treatment, and postoperative details. Time to surgery was calculated as the time from the initial presenting radiograph to the recorded time the patient entered the operating room. Posterior fixation methods and use of syndesmotic fixation were recorded. Patients with open fractures, ipsilateral midfoot or hindfoot injuries, contralateral foot and ankle injuries, incomplete medical records or radiographs, follow-up less than 8 weeks, an open physis, and pathologic fractures were excluded. Ankle fractures that underwent a resplinting event were excluded, assuming additional trauma to soft tissues. Additionally, a closed reduction with more than 5 mm of talar displacement relative to the tibia in the medial to lateral or anterior to posterior directions was excluded. A 5 mm cut-off was chosen to include an upper limit of acceptable closed reduction. Fractures were considered dislocated initially if, on any ankle radiograph, the talus was displaced 50% or more in any direction relative to the plafond. Instances of soft tissue complications (STC) were recorded, such as wound dehiscence, postoperative skin necrosis, and infection. These complications were further categorized as either nonoperative complications treated with modalities such as local wound care and/or antibiotics or operative complications treated with surgical intervention. Other complications, including pin site infections and pin site fractures, were recorded.
All patients received initial consultation and management in the emergency department setting by orthopaedic surgery residents in a level 1 trauma center and teaching hospital. Patients underwent initial closed reduction and plaster splinting in the emergency department, followed by either splint retention or temporary ex-fix before definitive open reduction internal fixation. The splinting components were the same in all patients, consisting of padding, below-knee plaster with a direct posterior slab and U configuration, following over-wrap with elastic bandage. The decision for ex-fix was made at the discretion of the attending surgeon. All events of ex-fix occurred within 24 hours of presentation to the treating center. Patients underwent definitive fixation when soft tissue conditions and operating room availability were amenable. Techniques for definitive fixation were variable depending on the fracture and treating surgeon, but predominantly included plate fixation of the fibula, screw fixation of the medial malleolus, suture or screw syndesmotic fixation when indicated, and plate or screw fixation of the posterior malleolus when felt indicated. Routine closures were performed with buried absorbable suture and nylon skin closure of variable patterns.
The typical treatment algorithm followed at each trauma center is notably different, but provided the framework for the study. The practice culture at trauma center 2 is use of temporary splinting until definitive fixation with very little use of ex-fix. This contrasts with trauma center 1, where ex-fix is frequently used for temporary stabilization. The majority of treating surgeons are either trauma or foot and ankle fellowship–trained surgeons.
Statistical Analysis
Statistical analyses were performed with IBM SPSS Statistics v27 (IBM Corporation, Armonk, NY). Tests conducted were 2-tailed and a P <.05 defined statistical significance. Normality was assessed by Shapiro-Wilk test (P > .05) and Q-Q Plot. Comparisons were conducted with Mann-Whitney U test, χ2 test, or Fisher exact test. Logistic regression was used to control for confounding in the STC comparison. Confounders were selected based on group imbalance and biological association with soft tissue complications. Multicollinearity and influential cases were absent.
Results
Between 2017 and 2023, 965 patients underwent operative ankle fracture fixation at 2 level 1 trauma centers (Figure 1). Excluded from analysis were 306 patients treated for tibial shaft fractures (10.9%, 105 of 965), pilon fractures (9.0%, 87 of 965), bimalleolar fractures (4.1%, 40 of 965), medial malleolus fractures (1.8%, 17 of 965), distal tibia fractures (0.9%, 9 of 965), Maisonneuve fractures without posterior malleolus facture (0.5%, 5 of 965), lateral malleolus fractures (0.3%, 3 of 965), or other midfoot, hindfoot, gunshot wound, and pathologic fractures (4.1%, 40 of 965). Of the remaining 659 patients, an additional 171 were excluded for having open injuries (13.9%, 92 of 659) or less than 8 weeks of follow-up (11.9%, 79 of 659).
Inclusion and exclusion process.
Overall, 488 patients met the inclusion criteria; 395 patients (80.9%) were managed with temporary splinting and 93 with ex-fix (19.1%). Both groups had similar distributions in age, sex, body mass index (BMI), smoking status, diabetes status, and fracture classifications (Table 1). Median follow-up was 24 weeks (range 8-292 weeks). Trauma center 1 performed ex-fix in 92 of 198 patients (46.4%), and trauma center 2 performed temporary splinting in 289 of 290 patients (99.6%). The most common fracture classification was 44B3.2 (67.2%, 328 of 488), followed by 44C2.3 (11.7%, 57 of 488) (Table 2). Neuropathy was more prevalent in ex-fix patients (10.8% [10 of 93] vs 2.0% [8 of 395]; P < .001). One neuropathic patient treated with temporary splinting experienced an STC. Dislocation at the time of injury was more prevalent in the ex-fix patients (88.2% [82 of 93] vs 62.0% [245 of 395]; P < .001). STC occurred in 6 of 82 dislocation ex-fix patients (7.3%) compared with 24 of 245 dislocation temporary splint patients (9.8%).
Comparisons of Group Characteristics and Outcomes. a
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; IQR, interquartile range; LOS, length of stay; STC, soft tissue complication.
Data are presented as n (%) unless otherwise specified.
BMI has 18.4% missing data.
Fracture Characteristics.
Abbreviation: AO/OTA, AO Foundation/Orthopaedic Trauma Association.
The cohort’s overall STC rate was 8.4% (41 of 488), including 2.9% (14 of 488) that required reoperation and 5.5% (27 of 488) that required nonoperative treatment. STC occurred in 6 of 93 ex-fix patients (6.5%) and 35 of 395 temporary splinting patients (8.9%) (risk difference −2.4% [95% CI −7.1% to 4.9%]; OR 0.70 [95% CI 0.28-1.74]; P = .45). When adjusted for confounding, ex-fix’s association with STC compared to temporary splinting was estimated at OR 0.93 (95% CI 0.30-2.87; P = .90) (Table 3). Reoperation for STC occurred in 3 of 93 ex-fix patients (3.2%) and 11 of 395 temporary splinting patients (2.8%) (risk difference 0.4% [95% CI −2.5% to 6.4%]; OR 1.16 [95% CI 0.31-4.25]; P = .73). A descriptive table of each patient requiring a reoperation for STC is shown in Table 4. The cohort’s overall redislocation rate was 1.6% (8 of 488), 1.3% (5 of 395) with temporary splinting, and 3.2% (3 of 93) with ex-fix. There were 2 superficial pin site infections that occurred in the ex-fix group. Both patients were treated with antibiotics and went on to successful union after definitive ORIF with no recurrent complications. There were no pin site–related fractures in the ex-fix group.
χ2 and Multivariable Logistic Regression Analysis of Soft Tissue Complications.
Abbreviation: OR, odds ratio.
Description of Patients Undergoing Reoperation for Soft Tissue Complications
Definitive Fixation >48 Hours
In patients receiving definitive fixation later than 48 hours from the time of presentation, 5 of 91 ex-fix patients (5.5%) experienced STC compared with 13 of 141 temporary splint patients (9.2%) (risk difference −3.7% [95% Cl −10.4% to 3.9%]; OR 0.57 [95% CI 0.19-1.66]; P = .30). Reoperation for STC was required in 2 of 91 ex-fix patients (2.2%) and 2 of 141 temporary splint patients (1.4%) (risk difference 0.7% [95% CI −3.1% to 6.3%]; OR 1.56 [95% CI 0.21-11.28]; P = .64).
Definitive Fixation >48 Hours and No Posterior Approach
In patients undergoing definitive fixation later than 48 hours from injury who received either no posterior fixation or limited screw fixation without a direct open approach to the posterior malleolus, 4 of 62 ex-fix patients (6.5%) experienced STC compared with 8 of 114 temporary splint patients (7.0%) (risk difference −0.5% [95% CI −7.9% to 9.0%]; OR 0.91 [95% CI 0.26-3.16]; P = .99). No patients required reoperation for STC in the splint group and 2 of 62 (3.2%) required reoperation in the ex-fix group.
Definitive Fixation Using a Posterior Approach With Direct Posterior Fixation
STCs were evaluated in patients that had either a posterior lateral or posterior medial approach to the posterior malleolus with fixation. In patients with a posterior approach, there were 10 of 86 patients (11.6%) with an STC vs 31 of 402 (7.7%) with no posterior approach (P = .28). When comparing between patients treated with ex-fix or splinting with and without posterior approaches, no difference was found (Table 5).
Soft Tissue Complications in Patients Treated With Splinting or External Fixation With and Without a Posterior Approach.
Discussion
This study could not identify clinically significant differences in soft tissue complications in patients treated with temporary ankle splinting vs ex-fix. Buyukkuscu et al 4 published 69 fracture dislocations treated with splinting vs 48 with ex-fix. The study included both bimalleolar and trimalleolar ankle fractures with more than 50% tibiotalar subluxation. They had higher rates of reduction loss with splinting at 25% vs 4% with ex-fix. Additionally, they found higher rates of skin necrosis with splinting vs ex-fix (22% vs 6%, P = .002). However, this finding did not result in significant differences in wound dehiscence or superficial infection. This study found higher rates of redislocation events compared with our study, which found a 1.3% (5 of 395) redislocation rate in splints and 3.2% (3 of 93) in ex-fix. Like our study, there was not a significant difference in wound dehiscence or infection between groups.
Gerlach et al 9 recently published their series of 162 fracture dislocations, 54 treated with ex-fix and 108 treated with splinting. The definition of dislocation in this study was 5 mm of displacement. They found perhaps a clinical but not a statistically significant difference in loss of reduction in the splinting group. The ex-fix group had higher rates of wound complications following surgery, but those rates were not statistically significant. In comparison, our study found slightly higher STC in the splint group vs the ex-fix group that was not statistically significant (8.9% vs 6.5%, P = .45).
In 2020, Wawrose et al 15 published a small retrospective series comparing 28 patients treated with splinting vs 28 patients treated with temporary ex-fix. They found a 50% redislocation rate in splinting vs 0% with ex-fix. They also reported that 5 of 28 patients in the splinting group developed anteromedial skin necrosis, whereas none in the ex-fix group developed skin necrosis. This study has a relatively small sample size; however, it did not find a significant difference in postoperative complications between groups, similar to our study.
The use of posterior approaches directed at fixation of posterior malleolus fractures has been associated with relatively high soft tissue complication rates. 10 Therefore, patients were subgrouped into those with and without approaches made to fix posterior malleolus fractures. Despite the grouping, no clinical or statistical difference could be found in STC. The previous studies discussed did not provide data of approach use.
To date, this study is the largest one focused on the topic. A clinically or statistically significant difference could not be identified in STC in patients treated with temporary splint vs ex-fix for ankle fractures with a posterior malleolus component. Regardless of treatment with splinting or ex-fix, the overall STC rate requiring reoperation was low at 2.9% (14 of 488).
There are several important features of the study design that should be discussed. Soft tissue complications were chosen as the primary outcome because it generally seems to be of interest and concern. 7 In addition, it is a reliable outcome to identify in a retrospective study. Minimum follow-up for this study was 8 weeks. Because the outcome variables studied were either in-hospital related or short-term wound complications, the follow-up timing was adequate. The median time to diagnosis of early infections after ankle fractures has been found to be 19 days in a previous study. 3 However, subgrouped data at minimum 6-month follow-up has also been provided in this study. Like other published studies on the topic, redislocations were identified either by routine radiographs in some cases or targeted radiographs with suspicion for dislocation. This study, as well as those previously discussed, were not specifically designed to identify joint reduction before definitive fixation, and therefore those results should be interpreted with caution. Only ankle fractures with a posterior malleolus component were included because this fracture type may be considered for ex-fix, whereas bimalleolar fractures generally are not. Moreover, posterior malleolus fracture patterns have been found to be more unstable, with larger fragment sizes associated with a higher risk of instability. 4
The study does have several limitations. The possibility of selection bias cannot be eliminated with this design. It is possible that some patients were selectively chosen for ex-fix for reasons such as poor soft tissue conditions in the setting of a closed fracture or concerning fracture characteristics not identified in this study. There was a higher rate of ex-fix in patients with neuropathy and dislocations. As indicated in Table 1, only 1 patient from trauma center 1 was managed with an ex-fix, which represents a known cultural difference in treatment trends between the 2 centers and allowed for an adequate sample size in each group to create the study. Therefore, selection bias would be expected to be decreased, although not eliminated, with this knowledge. Time to surgery is calculated from presentation to the treating hospital, which may not account for delayed presentations for a multitude of reasons.
The use of temporary ex-fix in these situations is influenced by many factors. One notable finding of this study is that equivocal results can be obtained with splinting. This assumes that skilled personnel are available at the emergency department level to reduce and appropriately splint unstable ankles, which may not always be the case. The authors believe there is a strong indication to consider ex-fix for ankles that are found to redislocate in a well-applied splint, with unfavorable soft tissues for definitive fixation.
Conclusion
The results of this study suggest similar rates of STC with ex-fix and splinting before definitive fixation of ankle fractures with a posterior malleolus component, even when accounting for utilization of posterior approaches and time to definitive fixation. Surgeons must consider if there is a benefit to use ex-fix, considering the additional cost and burden to patients.
Supplemental Material
sj-pdf-1-fai-10.1177_10711007251337743 – Supplemental material for Soft Tissue Complications Following Temporary External Fixation vs Splinting of Trimalleolar Ankle Fractures
Supplemental material, sj-pdf-1-fai-10.1177_10711007251337743 for Soft Tissue Complications Following Temporary External Fixation vs Splinting of Trimalleolar Ankle Fractures by Elias G. Joseph, Joseph Kocan, Mitchell Scull, Paul Mercado, Andrew W. Wilson, Bernard Rohrbacher, Bryce A. Cunningham, Dirk Kiner and Warren Gardner in Foot & Ankle International
Footnotes
Ethical Approval
Institutional Review Board approval for this retrospective review was obtained from the University at Buffalo IRB Study 00006258 and The University of Tennessee College of Medicine IRB Study 2013965.
Declaration of Conflicting Interests
The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Bryce A. Cunningham, MD, reports disclosures relevant to manuscript as paid consultant for Johnson & Johnson, DePuy Synthes. Dirk Kiner, MD, reports disclosures relevant to manuscript as paid consultant for Globus Medical. Disclosure forms for all authors are available online.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
Consent to participate
Due to the retrospective nature of the study, the requirement for participant consent was waived.
Data Availability
Data for this study are available from the corresponding author on reasonable request.
References
Supplementary Material
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