Open ankle fractures in the elderly: predisposing factors and the associated mortality.

The purpose of this study was to investigate the independent effect of open ankle fractures on postoperative mortality and to identify factors leading to open ankle fractures in the elderly population. This is a retrospective case-control study of 1,045 patients aged 65 years and older, with ankle fractures undergoing surgical fixation between 2010 and 2020 at three medical centers (Levels 1-2). A logistic regression analysis was used to identify risk factors for open fractures. Propensity score matching and survival analysis were used to measure the hazard of mortality attributable to open versus closed ankle fractures. There were 128 (12.2%) patients with open ankle fractures. Patients with open ankle fractures were more likely to be older, to be active smokers (OR = 1.7, p = 0.049), and tended to have a higher number of medical comorbidities including hypertension (OR = 2, p = 0.006) and chronic kidney disease (OR = 2.9, p = 0.005). Open ankle fractures were, independently of comorbid conditions and age, associated with higher risk of mortality (HR = 1.7, p = 0.03).

Critical Portions of a Foot or Ankle Surgical Procedure From Patient and Surgeon Perspectives.

BACKGROUND: Over the past decade, overlapping procedures in orthopaedic surgery have come under increased public scrutiny. Central to this discussion is what should constitute a "critical portion" of any surgical procedure-a definition which may differ between patients and surgeons. This study therefore aimed to assess which components of three common foot and ankle procedures are considered "critical" from both the patient and surgeon perspectives. METHODS: For this survey-based study, questionnaires were administered to patients who presented to an orthopaedic foot and ankle clinic and separately administered to foot and ankle surgeons through e-mail. The questionnaires broached all steps involved in three common foot and ankle procedures: open reduction and internal fixation of ankle fracture, Achilles tendon repair, and ankle arthroscopy. Respondents were asked to characterize each step as "always critical," "often critical," sometimes critical," rarely critical," or "never critical." A combined "always critical" and "often critical" response rate of greater than 50% was used to define a step as genuinely critical. Patient and surgeon responses were thereafter compared using Mann-Whitney U and Kruskal-Wallis tests ( P -value <0.05 was considered significant). RESULTS: Notably, both patients and surgeons considered informed consent, preoperative marking of the surgical site, preoperative time-out, surgical soft-tissue dissection, and certain procedure-specific steps (critical portions) of these procedures. By contrast, only patients considered skin incision and wound closure to be critical steps. CONCLUSION: Patients and surgeons were largely in agreement as to what should comprise the critical portions of several common foot and ankle procedures. Certain discrepancies did exist, however, such as skin incision and closure, and both groups were also in general agreement regarding what was not considered a critical component of these operations. Such findings highlight a potential opportunity for improved preoperative patient education and patient-physician communication. LEVEL OF EVIDENCE: Level IV: Evidence from well-designed case-control or cohort studies.

The Influence of Patient Characteristics and Social Determinants of Health on Postoperative Complications Following Achilles Tendon Rupture.

BACKGROUND: The influence of social determinants of health (SDH) on postoperative complications has been investigated in several studies, although correlation with Achilles tendon rupture (ATR) repair remains uninvestigated. SDH encompasses several factors, including insurance status and area-based measurements, including the Area Deprivation Index (ADI) and Social Vulnerability Index (SVI), which ranks neighborhoods by social disadvantage. This study investigated the correlation between patient demographics, SDH, and complications following ATR repair. METHODS: A retrospective cohort study was conducted on 521 patients who presented with acute ATR and met the inclusion criteria, including age ≥18 years, a minimum of 30-day follow-up, and repair within 28 days of rupture. We reviewed patient demographics, time to surgery (TTS), and postoperative complications, including venous thromboembolism (VTE), rerupture, surgical site infection (SSI), wound dehiscence, and sural nerve injury. SDH variables included race, smoking status, insurance status, level of education, ADI, and SVI. Univariate regression tested the correlation between complications and SDH indicators. Significant variables (P < .05) were included in a multivariate regression. RESULTS: Sixty-eight complications occurred in 59 patients (11.3%). Multivariate regression showed that a higher ADI, that is, socially deprived individuals, was associated with lower rates of VTE (OR = 0.41, P = .04). Higher body mass index (BMI) was associated with rerupture (OR = 8.73, P < .01). Male patients had lower rates of wound dehiscence (OR = 0.31, P = .03) and VTE (OR = 0.32, P = .02) compared with women. Longer TTS correlated with sural nerve injuries (OR = 2.23, P < .01) and shorter TTS with reruptures (OR = 0.02, P = .02). CONCLUSION: Some measures of SDH were associated with postoperative complications. Gender also may have an effect, with male sex associated with lower rates of wound dehiscence and VTE. BMI was associated with higher rates of reruptures and overall general complications.

Automation improves the efficiency of weightbearing CT scan 3D volumetric assessments of the syndesmosis.

BACKGROUND: Weight-bearing CT (WBCT) 3D volumetric measurement has shown promising accuracy for the diagnosis of syndesmotic instability. However, these measurements are rather complex and time-consuming, rendering them a clinically unfavorable option. We hypothesized that automatized measurements would be more accurate and time-efficient than manual ones. METHODS: Thirty cases of intraoperatively confirmed syndesmotic instability along with thirty individuals with no injuries to the ankle joint were recruited as cases and controls, retrospectively. Two observers conducted the manual volumetric measurements two times, at a one-week interval. An automated algorithm for 3D WBCT measurements was developed to conduct the measurements on the axial images. The time spent on each method was recorded. Mann-Whitney U test was used to compare the values between human raters and computers. Inter- and intra-class reliability were calculated. RESULTS: The intra-class correlation coefficient was found to be "excellent" for the automated measurements (0.97) and "good" for the observers (0.75). Similarly, the Cronbach's alpha was shown to be higher for the computer (0.88) than the observers (0.60 and 0.62). The mean time spent on the measurements was different between human raters and the computer-assisted method (p < 0.001). CONCLUSION: Automated volumetric assessment of syndesmosis seems to be a faster and more reliable option than the manual one. We suggest future larger-scale prospective studies conducted under actual clinical circumstances for more definitive conclusions. LEVEL OF EVIDENCE: Retrospective case-control study - Level 3.

Gender Differences in Achilles Tendon Ruptures-A Retrospective Study and a Review of the Literature.

Achilles tendon ruptures are common injuries typically sustained during sport with higher incidence in men, though little is understood regarding sex-specific risk factors or outcomes following injury management. This cross-sectional clinical study and systematic review aimed to examine sex-specific Achilles tendon rupture incidence and outcomes following intervention. This study included patients who sustained a rupture between 2011-2021, were ≥18 years old, and who had a minimum follow-up of at least six months, and evaluated age, sex, sport involvement, mechanism of injury, and postoperative complications and revision. Separately, a systematic literature review in the PubMed, EMBASE, and Cochrane databases was performed. A total of 705 male and 158 female patients were included in this retrospective study. 71.1% of men and 52.5% of women sustained a sports-related rupture (p < .001), with sport involvement demonstrating a positive correlation with revision rate (coefficient = 0.09, p = .02). A total of 21 studies with 250,907 patients (87,514 male, 35,792 female) were included in the systematic review. All studies revealed an increased incidence of ATR in men. Functional outcomes were worse in women, and female sex was an independent risk factor for postoperative complications and need for revision surgery. This study demonstrated a higher incidence of sports-related ATR in men than women, likely related to their higher ball sport participation. Although the retrospective analysis did not find a significant difference in complication or revision rates, the systematic review demonstrates poorer functional outcomes, with increased likelihood for postoperative complication and revision surgery in women as compared to men.

Unveiling Syndesmotic Malreduction: A Proof-of-Concept towards Portable Ultrasound Detection.

Objectives: To evaluate the utility and diagnostic performance of portable handheld ultrasound for evaluating fibular rotation at the distal tibiofibular articulation after syndesmotic disruption. Methods: Four above-the-knee cadaveric specimens were included. Syndesmotic disruption was precipitated by transecting the Anterior Inferior Tibiofibular Ligament, Interosseous Ligament, and Posterior Inferior Tibiofibular Ligament. Thereafter, a proximal fibular osteotomy was performed, and three conditions were modeled at the distal syndesmosis: 1) reduced, 2) 5 degree internal rotation malreduction, and 3) 5 degree external rotation malreduction. Two blinded observers performed separate ultrasonographic examinations for each condition at the level of both the anterior and posterior distal tibiofibular articular surfaces. Syndesmotic gap penetrance, defined as the ability of the P-US to generate signal between the distal fibula and tibia at the level of the incisura, was graded positive if the sonographic waves penetrated between the distal tibiofibular joint and negative if no penetrating waves were detected. The accuracy measures of the anterior and posterior gap penetrance were evaluated individually. Results: Our preliminary results showed that posterior gap penetrance showed good performance when detecting either internal or external rotational malreduction of the fibula with very good specificity (87.5%) and PPV (90.0%). On the other hand, the anterior gap penetrance showed limited performance when detecting either form of rotational malreduction. Conclusion: We introduced a novel sign, the "gap penetrance sign", best measured from the posterior ankle, which can accurately detect syndesmotic malreduction using P-US in a manner that does not require specific quantitative measurements and is readily accessible to early P-US users.

Using machine learning in the prediction of symptomatic venous thromboembolism following ankle fracture.

BACKGROUND: Venous thromboembolism (VTE) is a major cause of morbidity and mortality in the trauma setting, and both prediction and prevention of VTE have long been a concern for healthcare providers in orthopedic surgery. The purpose of this study was to evaluate the use of novel statistical analysis and machine-learning in predicting the risk of VTE and the usefulness of prophylaxis following ankle fractures. METHODS: The medical profiles of 16,421 patients with ankle fractures were screened retrospectively for symptomatic VTE. In total, 238 patients sustaining either surgical or nonsurgical treatment for ankle fracture with subsequently confirmed VTE within 180 days following the injury were placed in the case group. Alternatively, 937 patients who sustained ankle fractures managed similarly but had no documented evidence of VTE were randomly chosen as the control group. Individuals from both the case and control populations were also divided into those who had received VTE prophylaxis and those who had not. Over 110 variables were included. Conventional statistics and machine learning methods were used for data analysis. RESULTS: Patients who had a motor vehicle accident, surgical treatment, increased hospital stay, and were on warfarin were shown to have a higher incidence of VTE, whereas patients who were on statins had a lower incidence of VTE. The highest Area Under the Receiver Operating Characteristic Curves (AUROC) showing the performance of our machine learning approach was 0.88 with 0.94 sensitivity and 0.36 specificity. The most balanced performance was seen in a model that was trained using selected variables with 0.86 AUROC, 0.75 sensitivity, and 0.85 specificity. CONCLUSION: By using machine learning, this study successfully pinpointed several predictive factors linked to the occurrence or absence of VTE in patients who experienced an ankle fracture. Training these algorithms using larger, more granular, and multicentric data will further increase their validity and reliability and should be considered the standard for the development of such algorithms. LEVEL OF EVIDENCE: Case-Control study - 3.

The use of deep learning enables high diagnostic accuracy in detecting syndesmotic instability on weight-bearing CT scanning.

PURPOSE: Delayed diagnosis of syndesmosis instability can lead to significant morbidity and accelerated arthritic change in the ankle joint. Weight-bearing computed tomography (WBCT) has shown promising potential for early and reliable detection of isolated syndesmotic instability using 3D volumetric measurements. While these measurements have been reported to be highly accurate, they are also experience-dependent, time-consuming, and need a particular 3D measurement software tool that leads the clinicians to still show more interest in the conventional diagnostic methods for syndesmotic instability. The purpose of this study was to increase accuracy, accelerate analysis time, and reduce interobserver bias by automating 3D volume assessment of syndesmosis anatomy using WBCT scans. METHODS: A retrospective study was conducted using previously collected WBCT scans of patients with unilateral syndesmotic instability. One-hundred and forty-four bilateral ankle WBCT scans were evaluated (48 unstable, 96 control). We developed three deep learning models for analyzing WBCT scans to recognize syndesmosis instability. These three models included two state-of-the-art models (Model 1-3D Convolutional Neural Network [CNN], and Model 2-CNN with long short-term memory [LSTM]), and a new model (Model 3-differential CNN LSTM) that we introduced in this study. RESULTS: Model 1 failed to analyze the WBCT scans (F1 score = 0). Model 2 only misclassified two cases (F1 score = 0.80). Model 3 outperformed Model 2 and achieved a nearly perfect performance, misclassifying only one case (F1 score = 0.91) in the control group as unstable while being faster than Model 2. CONCLUSIONS: In this study, a deep learning model for 3D WBCT syndesmosis assessment was developed that achieved very high accuracy and accelerated analytics. This deep learning model shows promise for use by clinicians to improve diagnostic accuracy, reduce measurement bias, and save both time and expenditure for the healthcare system. LEVEL OF EVIDENCE: II.

Development and external validation of automated detection, classification, and localization of ankle fractures: inside the black box of a convolutional neural network (CNN).

PURPOSE: Convolutional neural networks (CNNs) are increasingly being developed for automated fracture detection in orthopaedic trauma surgery. Studies to date, however, are limited to providing classification based on the entire image-and only produce heatmaps for approximate fracture localization instead of delineating exact fracture morphology. Therefore, we aimed to answer (1) what is the performance of a CNN that detects, classifies, localizes, and segments an ankle fracture, and (2) would this be externally valid? METHODS: The training set included 326 isolated fibula fractures and 423 non-fracture radiographs. The Detectron2 implementation of the Mask R-CNN was trained with labelled and annotated radiographs. The internal validation (or 'test set') and external validation sets consisted of 300 and 334 radiographs, respectively. Consensus agreement between three experienced fellowship-trained trauma surgeons was defined as the ground truth label. Diagnostic accuracy and area under the receiver operator characteristic curve (AUC) were used to assess classification performance. The Intersection over Union (IoU) was used to quantify accuracy of the segmentation predictions by the CNN, where a value of 0.5 is generally considered an adequate segmentation. RESULTS: The final CNN was able to classify fibula fractures according to four classes (Danis-Weber A, B, C and No Fracture) with AUC values ranging from 0.93 to 0.99. Diagnostic accuracy was 89% on the test set with average sensitivity of 89% and specificity of 96%. External validity was 89-90% accurate on a set of radiographs from a different hospital. Accuracies/AUCs observed were 100/0.99 for the 'No Fracture' class, 92/0.99 for 'Weber B', 88/0.93 for 'Weber C', and 76/0.97 for 'Weber A'. For the fracture bounding box prediction by the CNN, a mean IoU of 0.65 (SD ± 0.16) was observed. The fracture segmentation predictions by the CNN resulted in a mean IoU of 0.47 (SD ± 0.17). CONCLUSIONS: This study presents a look into the 'black box' of CNNs and represents the first automated delineation (segmentation) of fracture lines on (ankle) radiographs. The AUC values presented in this paper indicate good discriminatory capability of the CNN and substantiate further study of CNNs in detecting and classifying ankle fractures. LEVEL OF EVIDENCE: II, Diagnostic imaging study.

Arthroscopic assessment of syndesmotic instability: Are we pulling correctly in the coronal plane?

BACKGROUND: While the lateral hook test (LHT) has been widely used to arthroscopically evaluate syndesmotic instability in the coronal plane, it is unclear whether the angulation of the applied force has any impact on the degree of instability. We aimed to determine if changing the direction of the force applied while performing the LHT impacts the amount of coronal diastasis observed in subtle syndesmotic injuries. METHODS: In 10 cadaveric specimens, arthroscopic evaluation of the syndesmotic joint was performed by measuring anterior and posterior-third coronal plane diastasis in the intact state, and repeated after sequential transection of the 1) anterior inferior tibiofibular ligament (AITFL), 2) interosseous ligament (IOL), and 3) posterior inferior tibiofibular ligament (PITFL). In all scenarios, LHT was performed under 100 N of laterally directed force. Additionally, LHT was also performed under: 1) anterior inclination of 15 degrees and 2) posterior inclination of 15 degrees in intact and AITFL+IOL deficient state. RESULTS: Compared to the intact state, the syndesmosis became unstable after AITFL +IOL transection under laterally directed force with no angulation (p = 0.029 and 0.025 for anterior and posterior-third diastasis, respectively), which worsened with subsequent PITFL transection (p = <0.001). Moreover, there was no statistical difference in anterior and posterior-third coronal diastasis in both intact and AITFL+IOL deficient states under neutral, anterior, and posteriorly directed force (p-values ranging from 0.816 to 0.993 and 0.396-0.80, respectively). However, in AITFL+IOL transected state, posteriorly directed forces resulted in greater diastasis than neutral or anteriorly directed forces. CONCLUSIONS: Angulation of the applied force ranging from 15 degrees anteriorly to 15 degrees posteriorly during intraoperative LHT has no effect on coronal plane measurements in patients with subtle syndesmotic instability. On the other hand, posteriorly directed forces result in more sizable diastasis, potentially increasing their sensitivity. CLINICAL RELEVANCE: When arthroscopically evaluating subtle syndesmotic instability, clinicians should assess coronal diastasis with the hook angled 15 degrees posteriorly.

Short-Term Risk Factors for Subtalar Arthrodesis After Primary Tibiotalar Arthrodesis.

While adjacent joint arthritis is a recognized long-term downside of primary tibiotalar arthrodesis (TTA), few studies have identified risk factors for early subtalar arthrodesis (STA) after TTA. This study aims to identify the risk factors for STA within the first few years following TTA. All patients older than 18 years undergoing TTA between 2008 and 2016 were identified retrospectively. Demographic data and comorbidities were collected alongside prior operative procedures, postoperative complications, and subsequent STA. Pre-and postoperative Kellgren-Lawrence osteoarthritis grade of the subtalar joint and postoperative radiographic alignment were obtained. A total of 240 patients who underwent primary TTA were included in this study with median follow up of 13.8 months. Twenty patients (8.3%) underwent STA after TTA due to symptomatic nonunion of TTA in 13 (65%), progression of symptomatic subtalar osteoarthritis (OA) in 4 (20%), and symptomatic nonunion of primary TTA combined progressively symptomatic subtalar OA in 2 (10%). Preoperative radiographic subtalar OA severity and postoperative radiographic alignment were not correlated with subsequent STA. Diabetes mellitus, Charcot arthropathy, neuropathy, alcohol use, substance use disorder, and psychiatric disease were significantly associated with having a subsequent STA. The most common postoperative contributing factor for subsequent STA following primary TTA was the salvage of symptomatic ankle nonunion rather than subtalar joint disease. Patients considering an ankle fusion should be counseled of the risk of subsequent STA, especially if they have risk factors that include diabetes, Charcot arthropathy, neuropathy, alcohol use, substance use disorder, or psychiatric disease.

Fluoroscopic Evaluation of the Role of Syndesmotic Injury in Lateral Ankle Instability in a Cadaver Model.

BACKGROUND: There is a high prevalence of concomitant lateral ankle ligament injuries and syndesmotic ligamentous injuries. However, it is unclear whether syndesmotic ligaments directly contribute toward the stability of the lateral ankle. Therefore, the aim of this study was to fluoroscopically evaluate the role of the syndesmotic ligaments in stabilizing the lateral ankle. METHODS: Twenty-four cadaveric specimens were divided into 3 groups and fluoroscopically evaluated for lateral ankle stability with all syndesmotic and ankle ligaments intact and then following serial differential ligamentous transection. Group 1: (1) anterior talofibular ligament (ATFL), (2) calcaneofibular ligament (CFL), and (3) posterior talofibular ligament (PTFL). Group 2: (1) anterior inferior tibiofibular ligament (AITFL), (2) interosseous ligament (IOL), (3) posterior inferior tibiofibular ligament (PITFL), (4) ATFL, (5) CFL, and (6) PTFL. Group 3: (1) AITFL, (2) ATFL, (3) CFL, (4) IOL, (5) PTFL, and (6) PITFL. At each transection state, 3 loading conditions were used: (1) anterior drawer test performed using 50 and 80 N of direct force, (2) talar tilt <1.7 Nm torque, and (2) lateral clear space (LCS) <1.7 Nm torque. These measurements were in turn compared with those of the stressed intact ligamentous state. Wilcoxon rank-sum test was used to compare the findings of each ligamentous transection state to the intact state. A P value <.05 was considered statistically significant. RESULTS: The lateral ankle remained stable after transection of all syndesmotic ligaments (AITFL, IOL, PITFL). However, after additional transection of the ATFL, the lateral ankle became unstable in varus and anterior drawer testing conditions (P values ranging from .036 to .012). Lateral ankle instability was also observed after transection of the ATFL and AITFL in varus and anterior drawer testing conditions (P values ranging from .036 to .012). Subsequent transection of the CFL and PTFL worsened the lateral ankle instability. CONCLUSION: Our findings suggest that isolated syndesmosis disruption does not result in lateral ankle instability. However, the lateral ankle became unstable when the syndesmosis was injured along with ATFL disruption. CLINICAL RELEVANCE: When combined with ATFL release, disruption of the syndesmosis appeared to destabilize the lateral ankle.

Detection of ankle fractures using deep learning algorithms.

BACKGROUND: Early and accurate detection of ankle fractures are crucial for optimizing treatment and thus reducing future complications. Radiographs are the most abundant imaging techniques for assessing fractures. Deep learning (DL) methods, through adequately trained deep convolutional neural networks (DCNNs), have been previously shown to faster and accurately analyze radiographic images without human intervention. Herein, we aimed to assess the performance of two different DCNNs in detecting ankle fractures using radiographs compared to the ground truth. METHODS: In this retrospective case-control study, our DCNNs were trained using radiographs obtained from 1050 patients with ankle fracture and the same number of individuals with otherwise healthy ankles. Inception V3 and Renet-50 pretrained models were used in our algorithms. Danis-Weber classification method was used. Out of 1050, 72 individuals were labeled as occult fractures as they were not detected in the primary radiographic assessment. Single-view (anteroposterior) radiographs was compared with 3-views (anteroposterior, mortise, lateral) for training the DCNNs. RESULTS: Our DCNNs showed a better performance using 3-views images versus single-view based on greater values for accuracy, F-score, and area under the curve (AUC). The highest sensitivity was 98.7 % and specificity was 98.6 % in detection of ankle fractures using 3-views using inception V3. This model missed only one fracture on radiographs. CONCLUSION: The performance of our DCNNs showed that it can be used for developing the currently used image interpretation programs or as a separate assistant solution for the clinicians to detect ankle fractures faster and more precisely. LEVEL OF EVIDENCE: III.

Isolated injuries to the lateral ankle ligaments have no direct effect on syndesmotic stability.

PURPOSE: This study aim was to detect the impact of lateral ankle ligaments injury on syndesmotic laxity when evaluated arthroscopically in a cadaveric model. The null hypothesis was that lateral ankle ligament injury does not affect the stability of syndesmosis. METHODS: Sixteen fresh-frozen above-knee amputated cadaveric specimens were divided into two groups of eight specimens that underwent arthroscopic evaluation of the distal tibiofibular joint. In both the groups, the assessment was first done with all syndesmotic and ankle ligaments intact. Thereafter, Group 1 underwent sequential transection of the three lateral ankle ligaments first to identify the effects of lateral ligament injury: (1) anterior talofibular ligament (ATFL), (2) calcaneofibular ligament (CFL), (3) posterior talofibular ligament (PTFL), then followed by the syndesmotic ligaments, (4) AITFL, (5) Interosseous ligament (IOL), and (6) PITFL. Group 2 underwent sequential transection of the (1) AITFL, (2) ATFL, (3) CFL, (4) IOL, (5) PTFL, and (6) PITFL, which represent the most commonly injured pattern in ankle sprain. In all scenarios, four loading conditions were considered under 100 N of direct force: (1) unstressed, (2) a lateral fibular hook test, (3) anterior to posterior (AP) fibular translation test, and (4) posterior to anterior (PA) fibular translation test. Distal tibiofibular coronal plane diastasis at the anterior and posterior third of syndesmosis, as well as AP and PA sagittal plane translation, were arthroscopically measured. RESULTS: The distal tibiofibular joint remained stable after transection of all lateral ankle ligaments (ATFL, CFL, and PTFL) as well as the AITFL. However, after additional transection of the IOL, the syndesmosis became unstable in both the coronal and sagittal plane. Syndesmosis laxity in the coronal plane was also observed after transection of the ATFL, CFL, AITFL, and IOL. Subsequent transection of the PITFL precipitated syndesmosis laxity in the sagittal plane, as well. CONCLUSIONS: The findings from the present study suggest that lateral ankle ligament injuries itself do not directly affect the stability of syndesmosis. However, if it combines with IOL injuries, even partial injuries cause syndesmotic laxity. As a clinical relevance, accurate diagnosis is the key for surgeons to determine syndesmosis fixation whether there is only AITFL injury or combined IOL injury in concomitant acute syndesmotic and lateral ligament injury.

Lisfranc injury: Refined diagnostic methodology using weightbearing and non-weightbearing radiographs.

BACKGROUND: To compare diagnostic parameters for Lisfranc instability on WB and NWB radiographs and to assess the inter-observer reliability of a standardized diagnostic protocol. PATIENTS AND METHODS: Patients who had undergone surgical treatment for subtle, purely ligamentous Lisfranc injury with both WB and NWB post-injury, pre-surgery films (n = 26) were included in this multicentre, retrospective comparative study. Also included was a control group (n = 26) of patients with isolated fifth metatarsal avulsion fractures who similarly had both WB and NWB films. Multiple midfoot distance and alignment measurements were used to evaluate the Lisfranc joint on both WB and NWB views. To evaluate interobserver reliability, measurements were made by two independent observers across a cohort subset. RESULTS: When comparing the NWB views between groups, only C1M2 (medial cuneiform- second metatarsal) distance was found to be significantly larger (∆ = 1.35 mm, p <0.001) for Lisfranc injuries. Most notably, C2M2 (Intermediate cuneiform - second metatarsal) step off-caused by lateral translation of the second metatarsal base-was not significantly different (∆ = 0.39 mm, p = 0.101) between Lisfranc patients and controls. On WB views, Lisfranc patients had significantly larger changes to C1M2 distance and C2M2 step-off as compared to controls (∆ = 2.97 mm, p <0.001 and ∆ =  1.98 mm, p <0.001 respectively). M1M2 (first to second intermetatarsal) distance was not significantly different between patients and controls in WB films. Within the cohort of ligamentous Lisfranc patients, C1M2 distance and C2M2 step-off were significantly larger in WB when compared to NWB films (∆ =  1.77 mm, p <0.001 and ∆ =  1.58 mm, p <0.001 respectively). For these parameters, inter-observer reliability scores (ICC) of >0. 90 were found when interpreting WB radiographs and ICC's ranging between 0.61 and 0.80 were found when interpreting NWB radiographs. CONCLUSION: Using WB imaging for diagnosing subtle Lisfranc instability reveals larger diastasis in the tarsometatarsal joint and has a higher interobserver reliability compared to NWB imaging. Clinical concern for subtle or occult Lisfranc instability in any patient should therefore trigger WB radiographic assessment since such injuries may be missed on NWB views.

Isolated Intermetatarsal Ligament Release as Primary Operative Management for Morton's Neuroma: Short-term Results.

BACKGROUND: Although the precise pathoetiology of Morton's neuroma remains unclear, chronic nerve entrapment from the overlying intermetatarsal ligament (IML) may play a role. Traditional operative management entails neuroma excision but risks unpredictable formation of stump neuroma. MATERIALS AND METHODS: Medical records were examined for adult patients who failed at least 3 months of conservative treatment for symptomatic and recalcitrant Morton's neuroma and who then underwent isolated IML decompression without neuroma resection. RESULTS: A total of 12 patients underwent isolated IML decompression for Morton's neuroma with an average follow-up of 13.5 months. Visual Analog Pain Scale averaged 6.4 ± 1.8 (4-9) preoperatively and decreased to an average of 2 ± 2.1 (0-7) at final follow-up (P = .002). All patients reported significant improvement. CONCLUSION: Isolated IML release of chronically symptomatic Morton's neuroma shows promising short-term results regarding pain relief, with no demonstrated risk of recurrent neuroma formation, permanent numbness, or postoperative symptom exacerbation. LEVEL OF EVIDENCE: Level IV: Case series.

Fusion Versus Joint-Sparing Reconstruction for Patients With Flexible Flatfoot.

AIMS: Passively correctible, adult-acquired flatfoot deformities (AAFD) are treated with joint-sparing procedures. Questions remain as to the efficacy of such procedures when clinical deformities are severe. In severe deformities, a primary fusion may lead to predictable outcomes, but risks nonunion. We evaluated pre- and postsurgical flexible AAFD patients undergoing joint-sparing or fusion procedures, comparing reoperation and complication rates. METHODS: We identified patients with flexible AAFD between January 1, 2001 and 2016. Exclusion criteria were incomplete medical record, rigid AAFD, and prior flatfoot surgery. Patient demographics, pre- and postsurgical radiographic measurements, surgery performed, and postoperative complications were evaluated by bivariate analysis, comparing joint-sparing versus fusion procedures. RESULTS: Of 239 patients (255 feet) (mean follow-up 62 ± 50 months), 209 (87%) underwent joint-sparing reconstructions, 30 (12.6%) underwent fusions. Fifty-four (24.1%) feet underwent joint-sparing reconstruction with reoperation versus 11 (35.5%) in fusion patients (P = .17). Radiographic improvement in talonavicular angle, talar first-metatarsal (anteroposterior view), and Meary's angle was higher in fusion patients (P < .001, P < .001, and P = .003, respectively). DISCUSSION: More nonunion reoperations among fusion patients were offset by reoperations in joint-sparing patients. Fusion uniquely corrected Meary's angle. Nonunion is of less concern for joint-sparing versus fusion for patients with severe flexible AAFD. Degree of deformity versus advantage of joint motion should improve decision making. LEVELS OF EVIDENCE: Level IV: Retrospective case series.

Diagnosis and Treatment of Syndesmotic Unstable Injuries: Where We Are Now and Where We Are Headed.

Up to 10% of ankle sprains are considered "high ankle" sprains with associated syndesmotic injury. Initial diagnosis of syndesmotic injury is based on physical examination, but further evaluation of the distal tibiofibular joint in the sagittal, coronal, and rotational planes is necessary to determine instability. Imaging modalities including weight-bearing CT and ultrasonography allow a physiologic and dynamic assessment of the syndesmosis. These modalities in turn provide the clinician useful information in two and three dimensions to identify and consequently treat syndesmotic instability, especially when subtle. Because there is notable variability in the shape of the incisura between individuals, contralateral comparison with the uninjured ankle as an optimal internal control is advised. Once syndesmotic instability is identified, surgical treatment is recommended. Several fixation methods have been described, but the foremost aspect is to achieve an anatomic reduction. Identifying any associated injuries and characteristics of the syndesmotic instability will lead to the appropriate treatment that restores the anatomy and stability of the distal tibiofibular joint.

Do Coronal or Sagittal Plane Measurements Have the Highest Accuracy to Arthroscopically Diagnose Syndesmotic Instability?

BACKGROUND: To compare the accuracy of arthroscopic sagittal versus coronal plane distal tibiofibular motion toward diagnosing syndesmotic instability. METHODS: Arthroscopic assessment of the syndesmosis was performed on 21 above-knee cadaveric specimens, first with all ligaments intact and subsequently with sequential transection of the anterior inferior tibiofibular ligament, the interosseous ligament, the posterior inferior tibiofibular ligament, and the deltoid ligament. A lateral hook test, an anterior-to-posterior (AP) translation test, and a posterior-to-anterior (PA) translation test were performed under 100 N of applied force. Anterior and posterior third coronal plane diastasis and AP and PA sagittal plane fibular translations were measured relative to the static tibia. RESULTS: Receiver operating characteristic (ROC) curve analysis revealed that the area under the curve (AUC) was higher for the combined AP and PA sagittal measurements (AUC, 0.91; accuracy, 83.5%; sensitivity, 78%; specificity, 89%) than the coronal plane measurements (anterior third: AUC, 0.65; accuracy, 60.5%; sensitivity, 63%; specificity, 59%; posterior third: AUC, 0.73; accuracy, 68.5%; sensitivity, 80%; specificity, 57%) (P < .001), underscoring the higher accuracy of sagittal plane measurements. CONCLUSION: Arthroscopic measurement of sagittal plane fibular translation is more accurate than coronal plane diastasis for evaluating syndesmotic instability. CLINICAL RELEVANCE: Clinicians should focus on distal tibiofibular motion in the sagittal plane when arthroscopically evaluating suspected syndesmotic instability. LEVEL OF EVIDENCE: Biomechanical cadaveric study.