Weight-bearing computed tomography (WBCT) was introduced in 2012 for foot and ankle applications as a breakthrough technology that enables full weight-bearing, three-dimensional imaging unaffected by x-ray beam projections or foot orientation. The literature describing the use of WBCT in the treatment of foot and ankle disorders is growing, and this article provides an overview of what can be measured with WBCT.

UNASSIGNED: Early detection of Lisfranc injury is critical for improving clinical outcomes, but diagnosing subtle injury can be difficult. Weightbearing computed tomography (WBCT) allows evaluation of such injuries in 3 dimensions (3D) under physiologic load. This study aimed to assess the utility of 1-, 2-, and 3-dimensional measurements on WBCT to diagnose subtle injury in isolated ligamentous Lisfranc injuries.
UNASSIGNED: Ten cadaveric specimens underwent WBCT evaluation of the Lisfranc joint complex in the intact state and subsequently with sequential sectioning of the dorsal Lisfranc ligament and interosseous Lisfranc ligament (IOL) to create subtle Lisfranc injury, and finally after transectioning of plantar Lisfranc ligament (PLL) to create the injury conditions for complete ligamentous Lisfranc injury. Measurements under static vertical tibial load of 80 kg were performed on WBCT images including (1) Lisfranc joint (medial cuneiform-base of second metatarsal) volume, (2) Lisfranc joint area, (3) C1-C2 intercuneiform area, (4) C1-M2 distance, (5) C1-C2 distance, (6) M1-M2 intermetatarsal distance, (7) first tarsometatarsal (TMT1) alignment, (8) second tarsometatarsal (TMT2) alignment, (9) TMT1 dorsal step-off distance, and (10) TMT2 dorsal step-off distance.
UNASSIGNED: In the subtle Lisfranc injury state, Lisfranc joint volume and area, C1-M2 distance, and M1-M2 distance measurements on WBCT significantly increased, when compared with the intact state (P values .001 to .014). Additionally, Lisfranc joint volume and area, C1-M2 distance, M1-M2 distance, TMT2 alignment, and TMT2 dorsal step-off measurements were increased in the complete Lisfranc injury state. Of all measurements, C1-M2 distance had the largest area under the curve (AUC) of 0.96 (sensitivity = 90%; specificity = 90%), followed by Lisfranc volume (AUC = 0.90; sensitivity = 80%; specificity = 80%) and Lisfranc area (AUC = 0.89; sensitivity = 80%; specificity = 100%).
UNASSIGNED: In a cadaveric model we found that WBCT scan can increase the diagnostic accuracy for subtle Lisfranc injury. Among the measurements, C1-M2 distance exhibited the highest level of accuracy. The 2D joint area and 3D joint volume also proved to be accurate, with 3D volume measurements of the Lisfranc joint displaying the most significant absolute difference between the intact state and increasing severity of Lisfranc injury. These findings suggest that 2D joint area and 3D joint volume may have potential as supplementary measurements to more accurately diagnose subtle Lisfranc injuries.
UNASSIGNED: WBCT may help surgeons detect subtle Lisfranc injuries.

BACKGROUND: Studies report that Lisfranc injury is more common than thought. Several imaging methods for assessing the stability of Lisfranc injury have been described but many are impossible to standardize and not accurate enough.
OBJECTIVE: To present a three-dimensional (3D) method for analyzing the changes in the joint space width of the midfoot joint and the joints of the medial part of the Lisfranc complex in healthy individuals.
METHODS: Non-weightbearing and weightbearing cone-beam computed tomography (CBCT) images of 11 healthy feet were acquired and analyzed with 3D software. The mean range of joint space width changes of each joint was computed from the changes in individual image pairs.
RESULTS: 3D analysis software was used to analyze the medial part of the Lisfranc complex. In this sample of healthy feet, the changes in the joint spaces in the medial part of Lisfranc complex, calculated with 3D analysis software, was less than 0.6 mm. The distance between bones increased or decreased, depending on which part of the joint surface the measurements were taken.
CONCLUSIONS: In this study, we present a 3D analysis method to evaluate midfoot joint space width changes. Our analysis revealed that in healthy feet there are only minimal changes in the joint space width between weightbearing and non-weightbearing indicating minimal movement of the midtarsal joints. The 3D analysis of weightbearing CBCT data provides a promising tool for analyzing the small midfoot joints in a variety of conditions.

UNASSIGNED: Primary arthrodesis of Lisfranc fracture-dislocations is a reliable treatment option, yet concerns remain about nonunion. Nitinol staple use has recently proliferated in midfoot arthrodesis. The purpose of this study is to examine the union rate of primary arthrodesis of acute Lisfranc fracture-dislocations treated with nitinol staples compared with traditional plate-and-screw fixation. The secondary objective is to assess the difference in operative times and reoperation rates.
UNASSIGNED: Midfoot fracture-dislocations treated with primary arthrodesis by 7 foot and ankle orthopaedic surgeons were reviewed. Of 160 eligible patients, 121 patients (305 joints) met the required 4-month minimum radiographic follow-up. Radiographic outcomes were analyzed at the individual joint level. Each joint was classified as either staples alone (45 patients, 154 joints), staples plus plates and screws (hybrid) (45 patients, 40 joints), or plates and screws alone (31 patients, 111 joints). The primary outcome was arthrodesis union at each joint fused.
UNASSIGNED: Nonunion was more common (9.0%, 10/111) among joints fixed with plate and screws than with hybrid (2.5%, 1/40) or staples only (1.3%, 2/154) (P = .0085). Multivariable regression demonstrated that autograft use was independent associated with union (P = .0035) and plate-and-screw only fixation was an independent risk factor for nonunion (P = .0407). Median operating room and tourniquet times were shorter for hybrid (92 and 83 minutes) and staple only (67 and 63 minutes) constructs compared to plate-and-screw only fixation (105 and 95 minutes) (P ≤ .0001 and .0003). There was no difference in reoperation rates among patients with different fixation types.
UNASSIGNED: We found that use of nitinol compression staple and bone autograft in primary arthrodesis of Lisfranc and midfoot fracture-dislocations was associated with both improved union rates and shorter tourniquet and operative times compared to traditional plate-and-screw fixation techniques.
UNASSIGNED: Level III, therapeutic.

Lisfranc injuries were thought to primarily occur during high-energy events, leading to a preference for fusion treatment; however, recent data have shifted this perspective by highlighting a greater occurrence of low-energy injuries and reshaping the focus on open reduction internal fixation. This multifaceted process is guided by various factors, including the nature of the injury, specific anatomic considerations, and the involved joints. Our overarching goal remains to achieve anatomic reduction, with flexibility in hardware fixation methods. In cases of comminution, bridge plating may be warranted, potentially followed by arthrodesis in the future.

Background During the COVID-19 pandemic, Americans transitioned away from their normal routines, drove in motor vehicles less, and reduced their physical activity, ultimately influencing the incidence and nature of orthopedic injuries that were operatively managed. The purpose of this study was to evaluate the effect of the COVID-19 pandemic lockdown and subsequent deconditioning on the mechanism of injury and severity of Lisfranc injury. Methods This retrospective study included patients with a traumatic Lisfranc injury who were surgically treated by a foot and ankle fellowship-trained orthopedic surgeon between 2015 and 2021. Electronic health records were queried for patient demographics, mechanism of injury, physical exam findings, and pain scores. Preoperative radiographs were reviewed to grade Lisfranc injuries using the previously described Nunley-Vertullo classification system. Descriptive and univariate statistics were performed to compare 15 patients in the pre-COVID-19 cohort and 15 patients in the post-COVID-19 cohort. Results In the pre-COVID-19 cohort, 80% (n=12/15) of the patients were female, the mean age was 46±15 years, the mean BMI was 29.7±7 kg/m2, and the mean follow-up period was 18.1±12 months. In the post-COVID-19 cohort, 53% (n=8/15) of the patients were female, the mean age was 48.5±17 years, the mean BMI was 31.4±7 kg/m2, and the mean follow-up period was 9.5±4 months. Significantly higher proportions of plantar ecchymosis (n=8/15, 53%), neuropathic pain (n=7/15, 47%), and swelling (n=12/15, 80%) were present in the post-COVID-19 cohort. A low-energy mechanism of injury was sustained by 73% (n=11/15) of the pre-COVID-19 cohort and 80% (n=12/15) of the post-COVID-19 cohort. Lisfranc injuries for the pre-COVID-19 cohort and the post-COVID-19 cohort demonstrated the following classifications: Grade 1 (33%, n=5/15 vs. 40%, n=6/15), Grade 2 (60%, n=9/15 vs. 53%, n=8/15), and Grade 3 (7%, n=1/15 vs. 7%, n=1/15). Conclusion Although a higher proportion of plantar ecchymosis, neuropathic pain, and swelling was observed, there was no association between a low mechanism of injury and a higher grade of Lisfranc injury following the COVID-19 pandemic.

BACKGROUND: Lisfranc injuries refer to a disruption or displacement of the tarsometatarsal joint of the foot. Subtle Lisfranc injuries can go undiagnosed on conventional imaging leading to devastating consequences and poor functional outcomes for elite athletes. Objective. The objective of this case study is to present a novel imaging technique using weight-bearing computed tomography (CT) with enhanced stress to identify subtle, dynamically unstable Lisfranc injuries. We illustrate this with a case presentation of an elite athlete who ultimately required surgical fixation for a subtle Lisfranc injury.
METHODS: To perform an augmented stress weight-bearing CT, the patient was positioned standing, with their feet facing forward, and weight equally distributed. The patient was then coached to symmetrically raise both heels from the scanner platform. This plantarflexion provided augmented stress on the midfoot, allowing for more sensitive imaging of the Lisfranc injury. The weight-bearing CT and augmented stress images undergo 3D reconstruction and postprocessing to render coronal and sagittal images, allowing for comparison of the standard weight-bearing and augmented stress images.
RESULTS: We present the case of a 22-year-old collegiate football lineman sustaining a Lisfranc injury. The injury diagnosis was made by magnetic resonance imaging (MRI) and clinical examination, without evidence of injury on weight-bearing XR or standard weight-bearing CT. With augmented stress CT imaging, the Lisfranc instability was noted, leading to surgical fixation, and return to sport the next season.
CONCLUSIONS: We propose this technique for diagnosing subtle, unstable Lisfranc injuries where clinical suspicion persists despite inconclusive imaging, particularly in elite athletes. Further research is needed with larger sample sizes to investigate the sensitivity of this novel imaging technique for the detection of Lisfranc injury.
UNASSIGNED: Level 4: Case Report.

Injury to the tarsometatarsal joint (TMT) results in instability throughout the midfoot that does not often improve with conservative management. If instability is identified, surgical intervention is frequently recommended, either open reduction and internal fixation (ORIF) or primary arthrodesis (PA). These 2 treatment options have been compared in the literature multiple times, often reporting similar outcomes. Due to this, as well as the need for subsequent hardware removal after ORIF has led many surgeons towards PA at the index surgery. Concern for nonunion is a leading concern with surgeons who advocate instead for ORIF. The purpose of this study is to review patients who underwent PA and observe nonunion rates. Nonunion at the TMT has been previously studied, but only in the chronic setting. We performed a retrospective study of 34 patients who had PA in the management of an acute Lisfranc injury. The average age in our study was 43.9 years old (range 19-72, SD 17.4) with an average follow-up of 9.4 months (range 4-33, SD 6.2). Radiographs were evaluated for signs of nonunion at regular postoperative intervals. Within the patients included in the study, a total of 71 TMT joints were fused. Overall successful fusion rate was 95.8% at an average of 7.9 weeks (range 6-12, SD 1.4) postoperatively. Individual nonunion rates at the first, second, and third TMT were 0%, 1.4% and 2.8% respectively. Our study demonstrates that primary arthrodesis provides a predictable outcome with low nonunion rates in the management of acute Lisfranc injury.

UNASSIGNED: There is a lack of consensus in the use of open reduction internal fixation (ORIF) vs primary arthrodesis (PA) in the management of Lisfranc injuries. Statistical fragility represents the number of events needed to flip statistical significance and provides context to interpret P values of outcomes from conflicting studies. The current study evaluates the statistical fragility of existing research with an outcome-specific approach to provide statistical clarity to the ORIF vs PA discussion. We hypothesized that statistical fragility analysis would offer clinically relevant insight when interpreting conflicting outcomes regarding ORIF vs PA management of Lisfranc injuries.
UNASSIGNED: All comparative studies, RCTs, and case-series investigating ORIF vs PA management of Lisfranc injuries published through October 5, 2023, were identified. Descriptive characteristics, dichotomous outcomes, and continuous outcomes were extracted. Fragility index and continuous fragility index were calculated by the number of event reversals needed to alter significance. Outcomes were categorized by clinical relevance, and median FI and CFI were reported.
UNASSIGNED: A total of 244 studies were screened. Ten studies and 67 outcomes (44 dichotomous, 23 continuous) were included in the fragility analysis. Of the 10 studies, 4 studies claimed PA to correlate with superior outcomes compared to ORIF with regard to functional scores and return to function outcomes. Of these 4 studies, 3 were statistically robust. Six studies claimed PA and ORIF to have no differences in outcomes, in which only 2 studies were statistically robust.
UNASSIGNED: The overall research regarding ORIF vs PA is relatively robust compared with other orthopaedic areas of controversy. Although the full statistical context of each article must be considered, studies supporting PA superiority with regard to functional scores and return to function metrics were found to be statistically robust. Outcome-specific analysis revealed moderate fragility in several clinically relevant outcomes such as functional score, return to function, and wound complications.

BACKGROUND: Traditionally, early surgical management of Lisfranc injuries with transarticular screws (TAS) was deemed to be the optimal treatment. However, concerns of potential iatrogenic articular cartilage disruption has led to discrepancies in opinion amongst surgeons, with many surgeons now utilizing dorsal bridge plates (DBP) for ORIF of Lisfranc injuries.
OBJECTIVE: This study sought to investigate the clinical outcomes at medium-term follow-up of consecutive patients in our institution who underwent ORIF with DBP for Lisfranc injuries.
METHODS: All consecutive patients who underwent ORIF with DBPs for Lisfranc injuries were identified. Outcomes of interest included; visual analogue scale (VAS), functional foot index (FFI), American Orthopaedic Foot & Ankle Surgeons (AOFAS) hindfoot scores, and complications.
RESULTS: Overall, 37 consecutive patients (24 males) with a mean age of 34.8 ± 13.0 years underwent ORIF with DBPs for lisfranc injuries. After a mean 48.3 ± 28.7 months, the mean reported AOFAS and FFI scores were 77.4 ± 23.8 and 31.9 ± 32.7 respectively, with satisfactory reported pain scores as measured by VAS post-operatively at rest and whilst walking (2.2 ± 2.5 and 3.1 ± 2.6 respectively). The reported satisfaction rate was 86.5% (32/37). Overall, 25 patients (67.6%) had subsequent removal of metal or were listed for same, 88% (22/25) of whom did so electively in the absence of broken screws or infection.
CONCLUSIONS: This study found that the use of Dorsal Bridge Plates for Open Reduction and Internal Fixation of Lisfranc Injuries resulted in satisfactory functional outcomes, high rates of patient-reported satisfaction and a low complication rate at medium-term follow-up.
METHODS: Level IV; Retrospective Series of Consecutive Patients.