Prediction of midfoot instability in the subtle Lisfranc injury. Comparison of magnetic resonance imaging with intraoperative findings

Effect of dorsoplantar miniscrew fixation of the second metatarsal base fracture on residual diastases in acute lisfranc fracture-dislocation

PURPOSE

This study aimed to evaluate and compare the clinico-radiographic outcomes between two techniques for acute Lisfranc fracture-dislocation with a large, displaced second metatarsal base plantar fracture: isolated Lisfranc screw fixation versus Lisfranc joint fixation with dorsoplantar miniscrew fixation of the second metatarsal base.

METHODS

We retrospectively compared the clinico-radiographic outcome between patients who underwent isolated Lisfranc screw fixation (Group 1, 26 patients) and those who underwent Lisfranc joint fixation with dorsoplantar miniscrew fixation of the second metatarsal base (Group 2, 23 patients). The main outcome measurements were the postoperative distance between the medial cuneiform and second metatarsal base on standing anteroposterior foot radiographs, known as the C1-M2 distance. Residual diastasis was defined as C1-M2 distance ≥ 2 mm on the affected side compared with that on the contralateral side. We also assessed the Foot and Ankle Ability Measure (FAAM)-activities of daily living (ADL) and sports subscale scores at three, six and ≥ 18 months postoperatively.

RESULTS

At the final follow-up, the mean C1-M2 distance on the affected side compared with that on the contralateral side was significantly greater in Group 1 than in Group 2 (3.9 versus 0.7 mm, P = 0.027). Furthermore, Group 1 showed a higher incidence of residual diastases at the final follow-up (69.2%) than the Group 2 (13.0%, P < 0.001). The FAAM-ADL scores at the final follow-up did not differ significantly between the groups (P = 0.518), but the FAAM Sports score was significantly higher in Group 2 than in Group 1 (P = 0.001).

CONCLUSIONS

The postoperative C1-M2 distance was better maintained with Lisfranc joint fixation with dorsoplantar miniscrew fixation of the second metatarsal base than with isolated Lisfranc screw fixation. We recommend that surgeons exercise caution when dealing with a second metatarsal plantar fracture and consider performing secure fixation using the dorsoplantar miniscrew technique for improved clinical outcomes.

The utility of point-of-care dynamic ultrasonography for the diagnosis of subtle isolated ligamentous Lisfranc injuries: a cadaveric study

OBJECTIVES

To assess if Lisfranc injury can be detected by US with and without abduction stress.

METHODS

Eight cadaveric feet were obtained. The following measurements were obtained in the uninjured feet: C1M2 and C1C2 intervals and TMT1 and TMT2 dorsal step-off distances. Measurements were obtained both with and without abduction stress using ultrasound. The injury model was created by transecting the Lisfranc ligament complex, after which the observers performed the measurements again. Statistical analysis was used to identify differences between intact and injured models, to determine diagnostic cut-off values for identifying Lisfranc injuries, and to assess interobserver/intraobserver reliability.

RESULTS

There was a significant difference in the mean C1M2 interval, both with and without abduction stress, between the intact and torn Lisfranc ligament (p < 0.001). A C1M2 interval with stress of > 2.03 mm yielded 81% sensitivity and 72% specificity for Lisfranc disruption. There was no significant difference in the mean C1C2 interval of the torn versus intact Lisfranc ligament without stress (p = 0.10); however, the distance was significantly different with the application of stress (p < 0.001). The C1C2 interval of > 1.78 mm yielded 72% sensitivity and 69% specificity for Lisfranc injury under stress. There were no significant differences in the mean TMT1 or TMT2 dorsal step-off measurements between the intact and torn Lisfranc ligaments. All observers showed good intraobserver ICCs. The interobserver ICCs for all measurements were good or excellent, except for TMT1, which was moderate.

CONCLUSION

Ultrasonography is a promising point-of-care imaging tool to detect Lisfranc ligamentous injuries when measuring C1M2 and C1C2 distances under abduction stress.

Lisfranc Injuries

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.

Augmented Stress Weight-bearing CT for Evaluation of Subtle Lisfranc Injuries in the Elite Athlete

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.

MATERIALS AND 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.

CONCLUSION

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.

LEVELS OF EVIDENCE

Level 4: Case Report.

Comparison of diagnostic performance of X‑ray, CT and MRI in patients with surgically confirmed subtle Lisfranc injuries

The present study aimed to compare the diagnostic performance of three imaging tests: X-ray, computed tomography (CT) and magnetic resonance imaging (MRI), for subtle Lisfranc injuries and three anatomical subtype injuries. The non-weight-bearing X-ray, CT and MRI imaging results of patients with subtle Lisfranc injuries from September 2013 to March 2022 were retrospectively reviewed. Subtle Lisfranc injuries and three anatomical subtypes (first, second and cuneiform rays) were diagnosed based on the surgical reports. The diagnostic performance of X-ray, CT and MRI was compared. The sensitivity (Sn), specificity (Sp), positive predictive value, negative predictive value, area under the receiver operating characteristic curve (AUC) and κ coefficient were reported. A total of 31 patients were included in the study. The correct diagnosis was made in 48.4% (15/31), 87.1% (27/31) and 96.8% (30/31) of patients by X-ray, CT and MRI, respectively. A total of 54 different anatomical injuries were found intraoperatively in all patients, with MRI and CT having high agreement (Sn, 72.2 and 87.0%; κ, 0.69 and 0.78, respectively) and X-ray having a low agreement (Sn, 29.6%; κ, 0.26) with the surgical findings. Regarding the first-ray injuries, CT had the highest Sn (76.9%), Sp (100%) and AUC (0.885) in diagnosing subtle Lisfranc injuries. MRI showed the best Sn (88.5 and 93.3%, respectively) and AUC (0.942 and 0.904, respectively) in both second and cuneiform rays. In conclusion, non-weight-bearing X-rays had poor diagnostic accuracy for subtle Lisfranc injuries and their subtypes. CT was superior to X-rays and MRI in diagnosing first-ray injuries. Although not significantly different from CT in terms of overall diagnosis, MRI was superior to X-ray and CT in diagnosing second and cuneiform-ray injuries.

Lisfranc Injury Diagnosis: What Is the Diagnostic Reliability of New Radiographic Signs Using Three-dimensional CT?

BACKGROUND

Up to one-third of Lisfranc injuries (an injury affecting the normal stability, alignment, and congruency of the tarsometatarsal joints) are misdiagnosed. Delayed diagnosis and improper treatment may lead to long-term, irreversible sequela and functional disability. Recently, the employment of three-dimensional (3D) CT demonstrated higher diagnostic reliability, but there is limited evidence on this, and radiologic features of Lisfranc injuries when using this diagnostic modality are not well described.

QUESTION/PURPOSE

What is the diagnostic performance of several novel radiographic signs on 3D CT when evaluating for Lisfranc injury, namely the Mercedes sign, the peeking metatarsal sign, and the peeking cuneiform sign, and what is the interobserver and intraobserver reliability of those diagnostic signs?

METHODS

In this retrospective, diagnostic study, video clips of 3D CT reconstructions of 52 feet with intraoperatively confirmed Lisfranc injuries and 50 asymptomatic feet with a normal appearance of the tarsometatarsal joints, as ascertained by a subspecialty-trained foot and ankle surgeon and a musculoskeletal radiologist, were analyzed by two foot and ankle specialists and three orthopaedic residents twice each, with a washout period of 2 weeks. Among the 52 patients with intraoperative evidence of Lisfranc injury, there were 27 male patients and 25 female patients, with a median (IQR) age of 40 years (23 to 58); among the 50 controls, there were 36 male and 14 female patients, with a median age of 38 years (IQR 33 to 49). For each video clip, the presence of all three radiographic signs was documented (each sign was rated in a binary yes/no fashion). Before the evaluations, all observers underwent a short training session by the head of the foot and ankle department. Later, these reading were used to assess for the sensitivity, specificity, and area under the receiver operating characteristic curve in terms of Lisfranc diagnosis against the gold standard of intraoperative testing of tarsometatarsal joint stability. Intraoperatively, the congruency and stability of the second tarsometatarsal joint had been evaluated by direct visualization and by the insertion of a probe into the joint between the base of the second metatarsus and the medial cuneiform and twisting the probe to assess for stability. The individuals evaluating the video clips were unaware of the surgically obtained diagnosis at the time they performed their evaluations.

RESULTS

All 3D radiographic signs that were examined had excellent diagnostic reliability in terms of sensitivity and specificity, ranging from 92% to 97% and from 92% to 93%, respectively. When assessing the association between the suggested 3D radiographic signs and Lisfranc injury diagnosis as a function of the area under the receiver operating characteristic curve, the Mercedes sign demonstrated a higher area under the curve than the other signs did (0.91 versus 0.87 versus 0.8; p < 0.001). The mean intraobserver and interobserver reliability (kappa) values were excellent for all 3D radiographic signs that were evaluated.

CONCLUSION

The proposed radiographic findings demonstrated excellent diagnostic performance and were repeatable within and among observers. Three-dimensional CT radiographic signs could function as a valuable diagnostic tool for the evaluation and initial screening for Lisfranc injury in the acute injury phase because obtaining AP bilateral standing radiographs of the foot is often impractical in the acute setting. Further research and comparison with AP weightbearing radiographs of the bilateral feet may be warranted.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Weightbearing Computed Tomography vs Conventional Tomography for Examination of Varying Degrees of Lisfranc Injures: A Systematic Review of the Literature

Background

Lisfranc injuries, if not accurately diagnosed, can result in chronic pain and instability. Previous studies have examined ultrasonographs, radiographs, magnetic resonance imaging (MRI), and conventional computed tomography (CT) scan to differentiate Lisfranc instability, but they focused on a healthy/injured scale without differentiating subtle injury. Weightbearing CT (WBCT) has emerged as a diagnostic tool for detecting subtle Lisfranc injuries. This systematic review aimed to compare WBCT with conventional CT in diagnosing Lisfranc injury, and the ability to differentiate injuries of varying severities.

Methods

The review encompassed PubMed, CINAHL, MEDLINE, SPORTDiscus, and Web of Science databases from inception until July 5, 2023. Inclusion criteria involved studies on CT and/or WBCT for Lisfranc injuries and nonoperative studies. Exclusion criteria composed case reports, commentaries, postoperative imaging studies, pediatric patients, studies with nonobjective radiographic measurements, studies exclusively focused on injury classification, and studies with fewer than 5 patients because of poor statistical power. Data extraction focused on radiographic measurements of the Lisfranc complex, categorized into conventional CT, partial WBCT, and total WBCT.

Results

Out of the initially retrieved 489 articles, 9 met the inclusion criteria. Several studies consistently demonstrate that WBCT provides a higher level of accuracy in measuring the Lisfranc area, offering enhanced sensitivity to detect subtle alterations in joint structure. Moreover, WBCT exhibits superior sensitivity in distinguishing between healthy Lisfranc joints and those with injuries, particularly when identifying dorsal ligament damage. This imaging modality allows for the detection of significant variations in critical measurements like first-second metatarsal (M1-M2) distance, first cuneiform (C1)-M2 distance, and joint volumes, enabling a more comprehensive assessment of Lisfranc joint health especially with subtle instability.

Conclusion

This review evaluates the extant literature on WBCT's utility in diagnosing Lisfranc injuries and compares its effectiveness to CT in distinguishing between injuries of varying severity. WBCT, with reliable measurement techniques, appears more adept at detecting subtle Lisfranc instability compared to CT, likely by allowing the assessment of injury under load.

Lisfranc Injury: Recent Trends in Management

Lisfranc injury refers to a group of bony or ligamentous injuries in which one or more of the metatarsals are displaced with respect to the tarsus. These injuries can occur as a result of either high-energy trauma like motor vehicle accidents and falls from height, or low-energy trauma from sports activities. A significant proportion of Lisfranc injuries are missed initially. The effects of delayed and missed diagnosed cases can be devastating as patients may develop progressive midfoot instability, collapse of arch, abduction of forefoot, and post-traumatic osteoarthritis, which can cause chronic pain, stiffness, and foot and ankle complex dysfunction. Favourable outcomes are associated with early diagnosis and prompt treatment. Open reduction and internal fixation (ORIF) with arthrodesis has better results than ORIF alone in functional outcomes. Dorsal bridge plates are currently the preferred mode of fixation due to advantages over trans-articular screws.

Is the diagnostic validity of conventional radiography for Lisfranc injury acceptable?

BACKGROUND

Lisfranc injuries mainly involve the tarsometatarsal joint complex and are commonly misdiagnosed or missed in clinical settings. Most medical institutions prefer to use conventional radiography. However, existing studies on conventional radiographs in Lisfranc injury lack a large population-based sample, influencing the validity of the results. We aimed to determine the diagnostic validity and reliability of conventional radiography for Lisfranc injury and whether computed tomography can alter clinical decision-making.

METHODS

This retrospective study included 307 patients with, and 100 patients without, Lisfranc injury from January 2017 to December 2019. Diagnosis was confirmed using computed tomography. A senior and junior surgeon independently completed two assessments of the same set of anonymised conventional radiographs at least 3 months apart. The surgeons were then asked to suggest one of two treatment options (surgery or conservative treatment) for each case based on the radiographs and subsequently on the CT images.

RESULTS

All inter- and intra-observer reliabilities were moderate to very good (all κ coefficients > 0.4). The mean (range) true positive rate was 81.8% (73.9%-87.0%), true negative rate was 90.0% (85.0%-94.0%), false positive rate was 10.0% (6.0%-15.0%), false negative rate was 18.2% (13.0%-26.1%), positive predictive value was 96.1% (93.8%-97.8%), negative predictive value was 62.4% (51.5%-69.7%), classification accuracy was 83.8% (76.7%-88.2%), and balanced error rate was 14.1% (10.2%-20.5%). Three-column injuries were most likely to be recognized (mean rate, 92.1%), followed by intermediate-lateral-column injuries (mean rate, 81.5%). Medial-column injuries were relatively difficult to identify (mean rate, 60.7%). The diagnostic rate for non-displaced injuries (mean rate, 76.7%) was lower than that for displaced injuries (mean rate, 95.5%). The typical examples are given. A significant difference between the two surgeons was found in the recognition rate of non-displaced injuries (p = 0.005). The mean alteration rate was 21.9%; the senior surgeon tended to a lower rate (15.6%) than the junior one (28.3%) (p < 0.001).

CONCLUSIONS

The sensitivity, specificity, and classification accuracy of conventional radiographs for Lisfranc injury were 81.8%, 90.0%, and 83.8%, respectively. Three-column or displaced injuries were most likely to be recognized. The possibility of changing the initial treatment decision after subsequently evaluating computed tomography images was 21.9%. The diagnostic and clinical decision-making of surgeons with different experience levels demonstrated some degree of variability. Protected weight-bearing and a further CT scan should be considered if a Lisfranc injury is suspected and conventional radiography is negative.

Lisfranc Injuries in the Athlete

LisFranc injuries in the active, athletic, and military populations can be devastating injuries. There has been much debate over open reduction and internal fixation versus arthrodesis as primary treatment in these injuries. This article aims to present the existing evidence-based medicine to help guide appropriate treatment in this population. With the introduction of flexible fixation, the variety of ways to address these injuries surgically has expanded.

Surgical controversies and current concepts in Lisfranc injuries

INTRODUCTION

Lisfranc injuries, not as rare as previously reported, range from ligamentous to complex fracture-dislocations. Anatomical studies have identified a complex of discrete structures, and defined the anatomical characteristics of the Lisfranc joint.

SOURCES OF DATA

A narrative evidence-based review encompassed and analyzed published systematic reviews. Outcomes included clinical and surgical decision-making, including clinical-presentation, diagnosis, pathological-assessment, surgical-management techniques and indications, post-surgical care and comparative outcomes.

AREAS OF AGREEMENT

Better understanding of the Lisfranc complex anatomy aids surgical treatment and tactics. Prognosis is related to injury severity, estimated by the number of foot columns affected. Surgical outcome is determined by anatomical reduction for most fixation and fusion techniques. Appropriate treatment allows return to sport, improving outcome scores.

AREAS OF CONTROVERSY

Identification of Lisfranc injuries may be improved by imaging modalities such as weight-bearing computer tomography. Recent evidence supports dorsal plate fixation as a result of better quality of reduction. In complex injuries, the use of combined techniques such as trans-articular screw and plate fixation has been associated with poorer outcomes, and fusion may instead offer greater benefits.

GROWING POINTS

Open reduction is mandatory if closed reduction fails, highlighting the importance of understanding surgical anatomy. If anatomical reduction is achieved, acute arthrodesis is a safe alternative to open reduction internal fixation in selected patients, as demonstrated by comparable outcomes in subgroup analysis.

AREAS FOR DEVELOPING RESEARCH

The current controversies in surgical treatment remain around techniques and outcomes, as randomized controlled trials are infrequent.

Lisfranc injury: Prevalence and maintaining a high index of suspicion for optimal evaluation

OBJECTIVES

To quantify the long-term prevalence of game-related Lisfranc trauma in college football on artificial turf and natural grass.

METHODS

32 universities were evaluated over 10 competitive seasons across all Football Bowl Subdivision (FBS) conferences. Outcomes of interest included injury severity, injury category, primary type of injury, player and skill position, injury mechanism and situation, elective imaging and surgical procedures, and field conditions. Injury incidence rates (IIR) were calculated using injuries per 10 games = (number of injuries) number of games) × 10.

RESULTS

Of the 1577 games documented, 783 games (49.7%) were played on a 3-layer artificial turf (≥9.0 lbs/ft²) infill system versus 794 games (50.3%) played on natural grass. In sum, 78 Lisfranc cases were documented with 34 (43.6%) occurring on artificial turf, and 44 (56.4%) on natural grass. MANOVAs indicated significant main effects by injury category (F_3,74 = 6.439; P = .001), and injury mechanism (F_5,72 = 3.372; P = .009) observed between surfaces, but not by injury severity (F_2,75 = 0.720; P = .490), primary type of injury (F_4,73 = 0.772; P = .547), overall player (F_2,75 = 0.219; P = .804) and skill positions (F_8,69 = 0.850; P = .563), injury situation (F_10,67 = 1.030; P = .428), elective imaging and surgical procedures (F_3,74 = 0.515; P = .673), or field conditions (F_2,75 = 0.375; P = .688). Post hoc analyses indicated significantly greater incidences (P < .05) of Lisfranc trauma on natural grass attributed to shoe:surface interaction during noncontact play, and during no contact, foot rotation or planting. Ligament tears (n = 8; 57.1%), with minimal cases of subluxation/dislocations (n = 4; 28.6%) and fractures (n = 2; 14.3%) comprised grade 3 cases across both surfaces.

CONCLUSION

In regards to Lisfranc trauma, a 3-layer, heavyweight artificial infill surface is as safe or safer than natural grass. The findings of this study may be generalizable only to this level of football competition.

Factors influencing postoperative residual diastasis after the operative treatment of acute Lisfranc fracture dislocation

INTRODUCTION

Clinically, surgeons may frequently encounter residual diastasis between the medial cuneiform and 2nd metatarsal base after the operative treatment of acute Lisfranc fracture dislocations. The purpose of this study was to identify factors influencing postoperative residual diastasis. We specifically focused on the preoperative fracture pattern using 3-dimensional computed tomography (3D-CT).

MATERIALS AND METHODS

Radiographic and clinical findings of 66 patients who underwent operative treatment for acute Lisfranc fracture dislocation were reviewed. Patients were grouped according to residual diastasis evaluated by weight-bearing anteroposterior radiograph of the foot at the final follow-up. Residual diastasis was defined as distance between the medial cuneiform and 2nd metatarsal base greater than the distance on the contralateral side by 2 mm or more. Demographic parameters and fracture patterns based on preoperative foot 3D-CT were compared. A paired t test was used to compare continuous numeric parameters, while a Chi-square test was used for the proportional parameters. Statistical significance was set at P value less than 0.05 for all analyses.

RESULTS

The mean age at operation, sex, body mass index, and the rate of underlying diabetes were not significantly different between the two groups (P > 0.05 each). Preoperative foot 3D-CT evaluation showed that the rate of large (> 25% of 2nd tarsometatarsal joint involvement), displaced (> 2 mm) fracture fragments on the plantar side of the 2nd metatarsal base was more pronounced in the group with residual diastasis (P = 0.001), while medial wall avulsion of the 2nd metatarsal base was more frequent in the group without residual diastasis (P = 0.001).

CONCLUSIONS

While treating acute Lisfranc injuries, surgeons should be aware of the presence of a 2nd metatarsal base plantar fracture. A dorsoplantar inter-fragmentary fixation can be considered if the fragment is large and displaced.

The role of three dimension computed tomography in Lisfranc injury diagnosis

PURPOSE

To evaluate the intra/inter observer and diagnostic reliability of 3-dimensional (3D) model reconstruction computed tomography (CT) compared to the traditional two-dimensional (2D) CT when evaluating Lisfranc (LF) injuries.

METHODS

A retrospective study was performed on CT studies of patients with clinically suspected LF injuries examined in the emergency department at medium size medical center. Each CT study was evaluated for metatarsal fractures and subluxations employing both standard 2D and 3D CT model reconstruction. Four orthopaedists, 2 senior and 2 residents, were assigned to review and evaluate each CT. Each CT study was reviewed twice by each reader in a randomized order. Descriptive statistics were calculated for all measured variables. The intra-observer and inter-observer agreement Kappa coefficients were calculated to evaluate reliability and reproducibility between and within readers for each modality.

RESULTS

The study included 44 patients. Median age was 41.4 years (interquartile range, 23-58). The intra-observer and inter-observer reliability was good (intra-observer; 3D Kappa; 0.76 and 2D Kappa 0.73 p<0.001, inter-observer; 3D Kappa 0.68, 2D Kappa 0.63 and combined 2D and 3D kappa 0.68, p<0.001). Three dimensional CT was found to be more sensitive than 2D CT, specifically when evaluating for second metatarsal dislocation (sensitivity: 70% vs 47%). Combined evaluation of 2D and 3D CT, greatly improved sensitivity rate to 85.7%. In terms of fracture diagnosis, combined evaluation of 2D and 3D CT showed higher sensitivity and specificity rates as compared to 2D or 3D alone.

CONCLUSION

The employment of 3D CT in LF injury diagnosis, in isolation and in combination with 2D CT, seems to improve the diagnostic accuracy and reliability between and within observers compared to 2D CT alone.

Deep Learning Algorithms Improve the Detection of Subtle Lisfranc Malalignments on Weightbearing Radiographs

BACKGROUND

Detection of Lisfranc malalignment leading to the instability of the joint, particularly in subtle cases, has been a concern for foot and ankle care providers. X-ray radiographs are the mainstay in the diagnosis of these injuries; thus, improving the performance of clinicians in interpreting radiographs can noticeably affect the quality of health care in these patients. Here we assessed the performance of deep learning algorithms on weightbearing radiographs for detection of Lisfranc joint malalignment in patients with Lisfranc instability.

METHODS

In a retrospective study, 640 patients with Lisfranc malalignment leading to instability were recruited plus 640 individuals with uninjured feet and healthy Lisfranc joint as the control group. All radiographs were screened by orthopaedic surgeons. Two deep learning models were trained, validated, and tested (in a ratio 80:10:10) using a single-view (anteroposterior) and 3-view (anteroposterior, lateral, oblique) radiographs. The performances of the models were reported as sensitivity, specificity, positive and negative predictive values, accuracy, F score, and area under the curve (AUC).

RESULTS

No significant differences were observed between the patients and the controls regarding age, gender, race, and body mass index. The best deep learning algorithm outperformed our human interpreters (<1% vs ~10% misdiagnosis), 94.8% sensitivity, 96.9% specificity, 98.6% accuracy, 95.8% F score, and 99.4% AUC.

CONCLUSION

Deep learning methods have shown promising potential in acting as an assistant interpreter of radiographic images in patients with Lisfranc malalignment. Developing these algorithms can hasten and improve the accuracy of diagnosis and reduce further costs and burdens on the patients and health care system.

LEVEL OF EVIDENCE

Level III, case-control Machine Learning study.

Outcome after nonoperative treatment of stable Lisfranc injuries. A prospective cohort study

BACKGROUND

The aim of this study was to evaluate the outcome after nondisplaced and stable Lisfranc injuries.

METHODS

26 patients with injuries to the Lisfranc joint complex detected on CT scans, but without displacement were tested to be stable using a fluoroscopic stress test. The patients were immobilized in a non-weightbearing short leg cast for 6 weeks. The final follow-up was 55 (IQR 53-60) months after injury.

RESULTS

All the Lisfranc injuries were confirmed to be stable on follow-up weightbearing radiographs at a minimum of 3 months after injury. Median American Foot and Ankle Society (AOFAS) midfoot score at 1-year follow-up was 89 (IQR 84-97) and at final follow-up 100 (IQR 90-100); The AOFAS score continued to improve after 1-year (P=.005). The median visual analog scale (VAS) for pain was 0 (IQR 0-0) at the final follow-up. One patient had radiological signs of osteoarthritis at 1-year follow-up.

CONCLUSION

Stable Lisfranc injuries treated nonoperatively had an excellent outcome in this study with a median follow-up of 55 months. The AOFAS score continued to improve after 1 year.

The Diagnostic Accuracy of MRI to Evaluate Acute Lisfranc Joint Injuries: Comparison With Direct Operative Observations

Background:

Early diagnosis is important in patients with Lisfranc joint injury to avoid subsequent complications. As the ligaments in the Lisfranc joint are relatively small and course obliquely, isotropic 3-dimensional (3D) magnetic resonance imaging (MRI) can be beneficial to evaluate ligament injury. The purpose of this study was to investigate the diagnostic accuracy of MRI, including isotropic 3D MRI for acute injury of the Lisfranc joint, especially of the interosseous C1-M2 ligament (Lisfranc ligament), the dorsal C1-M2 ligament (dorsal ligament), and the interosseous C1-C2 ligament, compared with direct operative observations.

Methods:

This retrospective review identified 27 patients who had undergone MR examination for acute Lisfranc joint injury followed by surgery. We reviewed the operative reports that described the Lisfranc, dorsal, and interosseous C1-C2 ligaments. All patients underwent an MRI, including a 2D oblique plane image parallel to the Lisfranc ligament and an isotropic 3D MRI. An image analysis of the integrity of the 3 ligaments and other associated injuries was performed. The diagnostic accuracy of MRI was analyzed using operative findings as a reference standard.

Results:

Lisfranc and dorsal ligament injuries were identified on MRI in all patients. MRI depicted disruption of the interosseous C1-C2 ligament in 12 patients. MRI diagnostic accuracy for detection of Lisfranc, dorsal, and interosseous C1-C2 ligaments was 100% (95% CI 0.82-1.0), 74% (95% CI 0.54-0.89), and 70% (95% CI 0.50-0.86), respectively.

Conclusion:

MRI with oblique planes parallel to the Lisfranc ligament and isotropic 3D MRI was reliable for detecting Lisfranc ligament injury, whereas MRI findings of the dorsal and interosseous C1-C2 ligaments were less consistent with operative observations.

Level of Evidence:

Level IV, case series.

The Lisfranc Injury: A Literature Review of Anatomy, Etiology, Evaluation, and Management

Despite being first described in the 1800s, the Lisfranc injury remains one of the most controversial topics in foot and ankle surgery. From the basic anatomy of the ligament complex to the optimal diagnostic and management methods, new research both sharpens and yet confounds our understanding of this unique injury. This article reviews the literature from established and classic papers to recent studies evaluating newer techniques. We discuss the unique bony and ligamentous anatomy, which confer strength to the Lisfranc complex, the typical mechanisms of injury, the most common classification systems, the clinical presentation, current imaging modalities, and conservative and surgical treatment options. We review studies comparing open reduction and internal fixation with primary arthrodesis of acute injuries, in addition to studies evaluating the various methods for obtaining fixation, including intra-articular screws, dorsal plates, and flexible fixation. It is clear from this review that despite the vast number of studies in the literature, much is still to be learned about the diagnosis and management of this challenging injury.Levels of Evidence: Level V: Expert opinion.

Isolated Medial Cuneiform Fractures: A Systematic Search and Qualitative Analysis of Case Studies

BACKGROUND

Isolated medial cuneiform fracture is a rare but diagnostically challenging condition. Diagnostic delay in these cases may lead to delays in ideal treatment approaches and prolonged symptoms. An understanding of clinical presentation is needed to expedite diagnosis, facilitate decision making, and guide treatment approach.

METHODS

Case studies/series were searched in four databases until September 2019. Included studies had participants with a history of traumatic closed medial cuneiform fracture. Studies were excluded if the medial cuneiform fractures were open fractures, associated with multitrauma, or associated with dislocation/Lisfranc injury. Three blinded reviewers assessed the methodological quality of the studies, and a qualitative synthesis was performed.

RESULTS

Ten studies comprising 15 patients were identified. Mean ± SD patient age was 38.0 ± 12.8 years, with 86.7% of reported participants being men. The overall methodological quality was moderate to high, and reporting of the patient selection criteria was poor overall. The most commonly reported clinical symptoms were localized tenderness (60.0%) and edema (53.3%). Direct blow was the most common inciting trauma (46.2%), followed by axial load (30.8%) and avulsion injuries (23.1%). Baseline radiographs were occult in 72.7% of patients; magnetic resonance imaging and computed tomography were the most common diagnostic modalities. Mean ± SD diagnostic delay was 64.7 ± 89.6 days. Conservative management was pursued in 54.5% of patients, with reported resolution of symptoms in 3 to 6 months. Surgical intervention occurred in 45.5% of patients and resulted in functional restoration in 3 to 6 months in all but one patient.

CONCLUSIONS

Initial radiographs for isolated medial cuneiform fractures are frequently occult. Due to expedience and relatively low cost, radiographs are still a viable first-line imaging modality. If clinical concern remains, magnetic resonance imaging may be pursued to minimize diagnostic delay. Conservative management is a viable treatment method, with expected return to full function in 3 to 6 months.

Case Study: The Conservative Management of a Complex Mid Foot Injury in an Elite Professional Footballer

Lisfranc injuries, often accompanied with tarsometatarsal joint (TMTJ) disruption, are not well documented in football despite becoming increasingly more prevalent within other athletic populations. Currently there is a paucity of evidence documenting prognosis, rehabilitation strategy and outcome. The presented case summarizes the conservative rehabilitation and return to play of a 26-year-old elite professional footballer who presented with a Lisfranc injury alongside a 3^rd TMTJ coalition stress response. Injury was sustained when landing awkwardly from a jump causing the midfoot to be forced into a hyper-plantarflexed position. Palpation identified tenderness over the 2^nd and 3^rd MT, with a positive piano key test. Magnetic resonance imaging (MRI), computed tomography (CT), stork view x-ray and review from a leading foot and ankle specialist confirmed diagnosis, post-contradictory MRI results. Presented is a summary of the assessment process, conservative management of the injury and the resultant rehabilitation process followed, which led to the successful return to play of the athlete.

In-Season Management of Acute and Subacute Sports Foot Injuries

In athletes, foot injuries present with a variety of mechanisms, severity, and implications for return to play. Although potentially given less attention than knee and shoulder injuries by the team physician, foot injuries are common and thus require knowledgeable consideration. In this article, we review the anatomy, presentation, workup, and management of several of the most common athletic foot injuries, including turf toe, Lisfranc injuries, Jones fractures, and navicular stress fractures. The goal is to provide the team physician with the information necessary to evaluate and manage these injuries on the sideline and in the training room.

Sports-Related Lisfranc Injuries and Recognition of Lisfranc Variants: Surgical Strategies for Stabilization

Much has changed since Lisfranc described lesions at the tarsometatarsal (TMT) joint in 1815. What was considered an osseous high-energy condition nowadays is understood as myriad possible presentations, occurring in minor and inconspicuous traumas. Advancements in diagnostics of Lisfranc injury allow recognizing many variants of this trauma presentation, most of them with a focus on ligaments. This perception shifted trends in surgical planning, especially for implants and fixation techniques. These revolutions established a new and evolving universe around TMT lesions, different from what was known only a few years ago and still not enough to completely settle the disease scenario.

Anatomy and biomechanics of the Lisfranc ligamentous complex: A systematic literature review

Lisfranc injuries are challenging to treat and can have a detrimental effect on active individuals. Over the past decade researchers have investigated methods for the reconstruction of the Lisfranc ligamentous complex (LLC) to preserve its functional stability and mobility. To aid in this innovation, this study presents the current understanding of the anatomical and biomechanical characteristics of the LLC through a systematic review. Three medical databases (PubMed, Scopus, and Embase) were searched from inception through July 2019. Original studies investigating the anatomy and/or biomechanical properties of the LLC were considered for inclusion. Data recorded from each study included: number of cadavers, number of feet, gender, laterality, age, type of specimen, measurement methods, reported ligamentous bundles, ligament origins and insertions, geometric characteristics, and biomechanical properties of the LLC. The Quality Appraisal for Cadaveric Studies (QUACS) scale was used to assess the methodologic quality of included articles. Eight cadaveric studies investigating the LLC were included out of 1204 screened articles. Most articles described the LLC as three distinct structures: the dorsal- (DLL), interosseous- (ILL), and plantar- (PLL) Lisfranc Ligaments. The ILL had the largest thickness and insertional area of osseous attachment. Biomechanically, the ILL also had the highest stiffness and resistance to load prior to failure when loaded parallel to its fiber orientation. Current knowledge of the anatomical and biomechanical properties of the LLC are presented and highlight its significant role of stabilizing the tarsometatarsal articulation. Appreciating the biomechanical characteristics of the ILL may improve clinical insight in managing LLC injuries.

Updates on Lisfranc Complex Injuries

Lisfranc injuries are a disruption of one or more of the tarsometatarsal joints and have an estimated incidence of 1/55 000 people. However, the total number of Lisfranc injuries could be underreported, because almost 20% of these injuries are initially missed. Because of the relative infrequency of these injuries, the current literature is inconsistent in regard to proper treatment. This article provides a review of Lisfranc complex injuries including relevant anatomy, diagnosis, treatment, classifications, operative approaches, and outcomes and complications. Based on existing evidence, it also proposes an algorithm the authors prefer for the evaluation and treatment of Lisfranc complex injuries.

Outcomes after nonoperatively treated non-displaced Lisfranc injury: a retrospective case series of 55 patients

BACKGROUND

Current knowledge of the role of the nonoperative treatment of Lisfranc injuries is based on a few retrospective case series. Hence, consensus on which patients can be treated nonoperatively does not exist. The aim of this study was to investigate outcomes after nonoperative treatment of Lisfranc injuries.

METHODS

In this study, patients were collected by recruiting all computer tomography-confirmed Lisfranc injuries treated during a 5-year period at a major trauma hospital. Between 2 and 6 years after suffering the injury, patients completed the visual analogue scale foot and ankle questionnaire.

RESULTS

In total, 55 patients returned adequately completed questionnaires and were included in the study. Of those, 22 patients had avulsion fractures and 33 had simple non-displaced intra-articular fractures. Of these patients, 30 (55%) scored over 90 points in both the pain and function subscales of the VAS-FA, and 35 (64%) scored over 90 points overall. In addition, three (5%) patients scored under 60 points in both the pain and function subscales of the VAS-FA, and four (7%) scored under 60 points overall. Only one patient with avulsion fractures underwent secondary surgery.

CONCLUSION

Nonoperative treatment has a role in the treatment of Lisfranc injuries, and the results of our study support the view that avulsion and simple intra-articular fractures with < 2 mm of displacement can be treated nonoperatively with high functional outcomes. The results of nonoperative and operative treatment should be compared in a prospective randomized controlled study setting in future studies.

LEVEL OF EVIDENCE

IV, retrospective case series.

Lisfranc injury: A review and simplified treatment algorithm

BACKGROUND

Lisfranc injuries encompass large spectrum of injuries varying from low energy to high energy complex fracture dislocations. Whilst multiple complex classification systems exist; these do little to aid and direct the clinical management of patients. Therefore, this study aims to provide a simplified treatment algorithm allowing clinicians to standardise care of Lisfranc injuries.

METHODS

A comprehensive literature search was performed, and abstracts were reviewed to identify relevant literature.

RESULTS

Delay in diagnosis has a negative impact on outcome. If a Lisfranc injury is suspected and plain radiographs are inconclusive; computed tomography and if necessary magnetic resonance imaging are indicated if there is still an index of suspicion. In the absence of joint dislocation/subluxation management will be determined by stability which can be best assessed by weightbearing radiographs. If stable, injuries can be treated conservatively in a non-weight bearing cast for 6 weeks followed by a period of graduated weight bearing. Evidence is mounting that with regard to unstable purely ligamentous Lisfranc injuries primary arthrodesis (PA) has: better functional outcomes, increased cost effectiveness and reduced rates of return to theatre. With regard to bony unstable Lisfranc injuries more research is required before a single treatment modality - PA or open reduction internal fixation can be advocated, due to the lack of randomized control trials and limited patient follow-up periods in existing studies.

CONCLUSION

A simplified treatment algorithm excluding the requirement for complex classifications is suggested. This may help with the diagnosis and management of these injuries. It is our believe that this algorithm will aid health professionals to standardize care for these injuries. Further prospective research trials are required to assess outcomes of different modalities of operative management, particularly with regards to open reduction and internal fixation versus primary arthrodesis for bony Lisfranc injuries.

LEVEL OF EVIDENCE

Level 5.

How to Identify Unstable Lisfranc Injuries? Review of Diagnostic Strategies and Algorithm Proposal

"Misdiagnosed Lisfranc injuries can be as high as 50%, leading to chronic pain, functional impairment, and posttraumatic arthritis. Subtle or incomplete lesions are the most problematic group for an adequate diagnosis. Conventional non-weight-bearing radiographs can overlook up to 30% of unstable cases. Abduction stress radiographs and anteroposterior monopodial comparative weight-bearing radiographic views are very useful to identify instability. Computed tomography gives detailed information about fracture patterns and comminution. MRI can predict instability but it is expensive and not readily available in the acute setting."

Change in the First Cuneiform-Second Metatarsal Distance After Simulated Ligamentous Lisfranc Injury Evaluated by Weightbearing CT Scans

BACKGROUND

This study aimed to investigate the widening between the first cuneiform (C1) and second metatarsal (M2) in a Lisfranc ligamentous complex (LLC) joint injury model subjected to successive ligament dissections evaluated by weightbearing computed tomography (CT) scans.

METHODS

Twenty-four intact cadaveric feet served as the control (condition 1). Each component of the LLC (dorsal, interosseous, and plantar ligaments-conditions 2, 3, and 4, respectively) were then sequentially dissected. The specimens were equally randomized to 1 of 3 additional dissections (first or second tarsometatarsal [TMT] joint capsule or first-second intercuneiform ligament [ICL]-conditions 5a, 5b, and 5c, respectively). One additional ligament was then randomly transected (eg, condition 6ac-transection of the first TMT capsule and ICL). Finally, the remaining ligament was transected (condition 7). After each dissection, CT scans were acquired under nonweightbearing (NWB, 0 kg), partial-weightbearing (PWB, 40 kg), and full-weightbearing (FWB, 80 kg) conditions. The distance between the lateral border of C1 and the medial border of M2 was assessed to evaluate diastasis. Linear regressions with 95% CIs and converted q values were used to compare the measured data.

RESULTS

No significant differences were found within the control. In condition 4, an average axial plane widening relative to control of 1.6 mm (95% CI, 1.5-1.8) and 2.1 mm (95% CI, 1.9-2.2) was observed under PWB and FWB. A coronal plane widening of 1.5 mm (95% CI, 1.3-1.6) and 1.9 mm (95% CI, 1.7-2.1) under PWB and FWB, respectively, was measured. A 95% CI of at least a 2-mm widening during PWB was demonstrated in 5c, 6ac, 6bc, and 7.

CONCLUSIONS

Weightbearing computed tomography (WBCT) scans were used to detect ligamentous Lisfranc injuries in a cadaveric model. Relative axial widening greater than 1.5 mm under PWB conditions could indicate a complete LLC injury. Complete transection of the intercuneiform 1-2 ligament was required to detect a 2-mm widening in the nonweightbearing condition.

CLINICAL RELEVANCE

This study provides insight on the detection of various severities of LLC injuries using WBCT imaging.

Clinical study on the surgical treatment of atypical Lisfranc joint complex injury

BACKGROUND

Lisfranc injuries have not received much attention by orthopedic doctors in the past, and there is little related research on the diagnosis and treatment of these injuries. In recent years with the rise in foot and ankle surgery, doctors are now paying more attention to this type of injury. However, there is still a high rate of missed diagnosis due to insufficient attention causing treatment delays or inadequate treatments, which eventually result in greater sequelae; including long-term pain, arthritis, foot deformity etc. In particular, for cases with a mild Lisfranc joint complex injury, the incidence of sequelae is higher.

AIM

To select an active surgical treatment for an atypical Lisfranc joint complex injury and to evaluate the clinical efficacy of the surgical treatment.

METHODS

The clinical data of 18 patients, including 10 males and 8 females aged 20-64 years with Lisfranc injuries treated in our department from January 2017 to September 2019 were retrospectively analyzed. All patients were treated with an open reduction and internal fixation method using locking titanium mini-plates and hollow screws or Kirschner wires. X-ray images were taken and follow-up was performed monthly after the operation; the internal fixation was then removed 4-5 mo after the operation; and the American Orthopedic Foot and Ankle Society (AOFAS) score was used for evaluation on the last follow-up.

RESULTS

All patients were followed up for 6-12 mo. A good/excellent AOFAS score was observed in 88.9% of patients.

CONCLUSION

For atypical Lisfranc joint complex injuries, active open reduction and internal fixation can be performed to enable patients to obtain a good prognosis and satisfactory functional recovery.

Asymmetric lambda sign of the second tarsometatarsal joint on axial weight-bearing cone-beam CT scans of the foot: preliminary investigation for diagnosis of subtle ligamentous Lisfranc injuries in a cadaveric model

BACKGROUND

Subtle Lisfranc joint injuries remain challenging to diagnose. Although of questionable accuracy, the current gold standard to assess these injuries is through bilateral weight-bearing radiography. However, weight-bearing cone beam-computed tomography (CBCT), providing clearer visualization of bony landmarks, can also be utilized for evaluation. This study aims to establish the hypothesis that a specific weight-bearing CBCT finding (asymmetric lambda sign) can serve as an independent indicator of a subtle Lisfranc injury.

METHODS

Weight-bearing CBCT images of 24 match-paired cadaveric legs were acquired, initially intact, and then following sequential dissection of each aspect (dorsal, interosseous, and plantar ligaments, respectively) of the Lisfranc ligamentous complex (LLC). All scans were taken in non- (NWB, 0 kg), partial- (PWB, 40 kg), and full-weight-bearing (FWB, 80 kg) manners. The lambda sign was then inspected axially for asymmetry (positive sign) by identifying three symmetrical joint spaces created between the medial cuneiform and the second metatarsal base (C1-M2), the medial and middle cuneiform (C1-C2), and the second metatarsal base and middle cuneiform (M2-C2).

RESULTS

A positive sign was observed in 25.6% (221/864) of all studies. Most notably, the fully dissected specimens demonstrated an asymmetric lambda sign in 33.3%, 72.2%, and 83.3% in NWB, PWB, and FWB conditions, respectively. The inter- and intra-observer reliability kappa value was calculated to be 0.843 and 0.912.

CONCLUSION

An asymmetric lambda sign is a simple and useful indicator for a complete LLC injury in PWB and FWB conditions using a cadaver model.

Magnetic resonance imaging of the ankle and foot

This article reviews the magnetic resonance imaging (MRI) findings of the normal anatomy and various pathologic conditions of the ankle and foot commonly encountered in clinical practice. The spectrum of entities discussed includes osseous and osteochondral injuries, ligamentous injuries, common traumatic and degenerative tendon pathology, abnormalities of transverse tarsal joint (Chopart) and tarsometatarsal joint (Lisfranc) complexes, pathological conditions affecting capsuloligamentous structures of the great toe and lesser toes, as well as pedal infection, with a focus on diabetic osteomyelitis and neuropathic osteoarthropathy.

Lisfranc injuries: Incidence, mechanisms of injury and predictors of instability

BACKGROUND

In Lisfranc injuries the stability of the tarsometatarsal joints guides the treatment of the injury. Determining the stability, especially in the subtle Lisfranc injuries, can be challenging. The purpose of this study was to identify incidence, mechanisms of injury and predictors for instability in Lisfranc injuries.

METHODS

Eighty-four Lisfranc injuries presenting at Oslo University Hospital between September 2014 and August 2015 were included. The diagnosis was based on radiologically verified injuries to the tarsometatarsal joints. Associations between radiographic findings and stability were examined.

RESULTS

The incidence of Lisfranc injuries was 14/100,000 person-years, and only 31% were high-energy injuries. The incidence of unstable injuries was 6/100,000 person-years, and these were more common in women than men (P = 0.016). Intraarticular fractures in the two lateral tarsometatarsal joints increased the risk of instability (P = 0.007). The height of the second tarsometatarsal joint was less in the unstable injuries than in the stable injuries (P = 0.036).

CONCLUSION

The incidence of Lisfranc injuries in the present study is higher than previously published. The most common mechanism of injury is low-energy trauma. Intraarticular fractures in the two lateral tarsometatarsal joints, female gender and shorter second tarsometatarsal joint height increase the risk of an unstable injury.

LEVEL OF EVIDENCE

Level III, cross-sectional study.

Surgical outcome of chronic Lisfranc injury without secondary degenerative arthritis: A systematic literature review✰

BACKGROUND

Chronic Lisfranc joint injuries (tarsometatarsal, TMT) can present as a variety of clinical symptoms and radiographic findings. If significant arthritis at the Lisfranc joint is present, salvage arthrodesis is an option. For patients who receive a delayed diagnosis and/or present with no signs of arthritic changes, selecting the most appropriate treatment can be challenging. This article provides a systematic review of current surgical treatment options and outcomes for patients with a chronic Lisfranc injury but no secondary degenerative changes.

METHODS

Four major medical databases were searched from inception through March 5, 2019: PubMed, Science Direct, Scopus, and Embase. Studies were included if they were original research studies that assessed the outcome of patients treated surgically for chronic Lisfranc injuries without secondary osteoarthritic changes. Only studies written in English and German were considered. The following data were recorded from each study: number of patients and feet included, study design (prospective vs. retrospective, single vs. multicenter, level of evidence), time between initial injury and operation, operative techniques, age, mechanism of injury, type of injury (purely ligamentous or ligamentous with concomitant bony fractures), indications for surgery, pre-operative assessment, postoperative follow-up time, time to return to activity or sport, and clinical outcome. The modified Coleman Score was used to assess the methodologic quality of the included studies.

RESULTS

Of the 6,845 screened, ten studies met the above criteria and were included. All but one were single center studies. All studies were either retrospective or prospective case series. Overall, studies generally reported low complication rates and good functional outcomes. Postoperative outcomes were most frequently measured with the American Orthopaedic Foot and Ankle (AOFAS) score; the overall mean preoperative AOFAS scores of 55.7 significantly improved to 88.1 at final follow-up.

CONCLUSIONS

No definitive consensus exists on how Lisfranc instability without concurrent osteoarthritis should be surgically managed. Despite the delay in diagnosis, patients who undergo surgical repair for chronic, unstable Lisfranc injury without osteoarthritis have improved patient outcome and few post-surgical complications. While the quality of these studies is satisfactory, a larger patient cohort and prospective analysis could further strengthen arguments for or against certain surgeries.

LEVEL OF EVIDENCE

Level IV; Systematic Review of Level IV Studies.

ACR Appropriateness Criteria® Acute Trauma to the Foot

Acute injuries to the foot are frequently encountered in the emergency room and in general practice settings. This publication defines best practices for imaging evaluations for several variants of patients presenting with acute foot trauma. The variants include scenarios when the Ottawa rules can be evaluated, when there are exclusionary criteria, and when suspected pathology is in anatomic areas not addressed by the Ottawa rules. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Imaging in Lisfranc injury: a systematic literature review

OBJECTIVES

To systematically review current diagnostic imaging options for assessment of the Lisfranc joint.

MATERIALS AND METHODS

PubMed and ScienceDirect were systematically searched. Thirty articles were subdivided by imaging modality: conventional radiography (17 articles), ultrasonography (six articles), computed tomography (CT) (four articles), and magnetic resonance imaging (MRI) (11 articles). Some articles discussed multiple modalities. The following data were extracted: imaging modality, measurement methods, participant number, sensitivity, specificity, and measurement technique accuracy. Methodological quality was assessed by the QUADAS-2 tool.

RESULTS

Conventional radiography commonly assesses Lisfranc injuries by evaluating the distance between either the first and second metatarsal base (M1-M2) or the medial cuneiform and second metatarsal base (C1-M2) and the congruence between each metatarsal base and its connecting tarsal bone. For ultrasonography, C1-M2 distance and dorsal Lisfranc ligament (DLL) length and thickness are evaluated. CT clarifies tarsometatarsal (TMT) joint alignment and occult fractures obscured on radiographs. Most MRI studies assessed Lisfranc ligament integrity. Overall, included studies show low bias for all domains except patient selection and are applicable to daily practice.

CONCLUSIONS

While conventional radiography can demonstrate frank diastasis at the TMT joints; applying weightbearing can improve the viewer's capacity to detect subtle Lisfranc injury by radiography. Although ultrasonography can evaluate the DLL, its accuracy for diagnosing Lisfranc instability remains unproven. CT is more beneficial than radiography for detecting non-displaced fractures and minimal osseous subluxation. MRI is clearly the best for detecting ligament abnormalities; however, its utility for detecting subtle Lisfranc instability needs further investigation. Overall, the available studies' methodological quality was satisfactory.

Inter- and intraobserver reliability of non-weight-bearing foot radiographs compared with CT in Lisfranc injuries

BACKGROUND

Injury of the tarsometatarsal (TMT) joint complex, known as Lisfranc injury, covers a wide range of injuries from subtle ligamentous injuries to severely displaced crush injuries. Although it is known that these injuries are commonly missed, the literature on the accuracy of the diagnostics is limited. The diagnostic accuracy of non-weight-bearing radiography (inter- or intraobserver reliability), however, has not previously been assessed among patients with Lisfranc injury.

METHODS

One hundred sets of foot radiographs acquired due to acute foot injury were collected and anonymised. The diagnosis of these patients was confirmed with a CT scan. In one-third of the radiographs, there was no Lisfranc injury; in one-third, a nondisplaced (< 2 mm) injury; and in one-third, a displaced injury. The radiographs were assessed independently by three senior orthopaedic surgeons and three orthopaedic surgery residents.

RESULTS

Fleiss kappa (κ) coefficient for interobserver reliability resulted in moderate correlation κ = 0.50 (95% CI: 0.45- 0.55) (first evaluation) and κ = 0.58 (95% CI: 0.52-0.63) (second evaluation). After three months, the evaluation was repeated and the Cohen's kappa (κ) coefficient for intraobserver reliability showed substantial correlation κ = 0.71 (from 0.64 to 0.85). The mean (range) sensitivity was 76.1% (60.6-92.4) and specificity was 85.3% (52.9-100). The sensitivity of subtle injuries was lower than severe injuries (65.4% vs 87.1% p = 0.003).

CONCLUSIONS

Diagnosis of Lisfranc injury based on non-weight-bearing radiographs has moderate agreement between observers and substantial agreement between the same observer in different moments. A substantial number (24%) of injuries are missed if only non-weight-bearing radiographs are used. Nondisplaced injuries were more commonly missed than displaced injuries, and therefore, special caution should be used when the clinical signs are subtle.

LEVEL OF EVIDENCE

III.

Update on Investigation Methods for Lower Extremity Biomechanics

Imaging with biomechanical analysis augments the clinical examination and improves outcomes by correlating imaging findings with the examination. Plain film radiographs are the gold standard to assess osseous alignment. The biomechanical examination provides information to formulate an accurate assessment. Weightbearing computed tomography scanning is a potentially valuable for functional information about joint biomechanics. True alignment of the lower extremity can be appreciated on weightbearing computed tomography scanning. Soft tissue structures can be assessed with diagnostic ultrasound examination. Acute and chronic injuries that compromise joint stability can be identified.

Undisplaced subtle ligamentous Lisfranc injuries, conservative or surgical treatment with percutaneous position screws?

PURPOSE

Undisplaced subtle ligamentous Lisfranc injuries are easy to miss or underestimate, and many cases are treated without surgical fixation. It has not yet widely known whether conservative treatment for undisplaced subtle ligamentous Lisfranc injuries may lead to a poor outcome. The purpose of this study is to compare the outcomes of conservative versus surgical management (percutaneous position screw) of undisplaced subtle ligamentous Lisfranc injury.

METHODS

We analysed 61 cases in this retrospective study, including 38 males and 23 females. Forty-one patients were managed conservatively, while 20 patients received surgical treatment involving minimal invasive percutaneous position screw. American orthopaedic foot &ankle society (AOFAS), foot function index (FFI, including FFI disability, FFI pain score and activity limitation scale) scores, Maryland foot score and short form-36 (SF-36) were recorded and compared after a follow-up of 10-16 months (average 12.3).

RESULTS

Patients in the surgical management group had higher scores in all evaluation methods (p < 0.05). The complications in the conservative management group had higher incidence, mainly including secondary diastasis (34.1% vs. 5.0%), joint stiffness after 3 months (82.9% vs. 0%), and secondary arthrodesis (12.2% vs. 0%). The highest rate of complication in surgical management group was temporary forefoot pain (55.0%).

CONCLUSION

The results of this study suggest that the outcomes of the surgical management with percutaneous position screw fixation are better than the conservative management to treat undisplaced subtle ligamentous Lisfranc injuries. This study can serve as a resource for orthopaedic surgeons in recognizing and managing such injuries.

Lisfranc fracture-dislocations: current management

It is essential to know and understand the anatomy of the tarsometatarsal (TMT) joint (Lisfranc joint) to achieve a correct diagnosis and proper treatment of the injuries that occur at that level.

Up to 20% of Lisfranc fracture-dislocations go unnoticed or are diagnosed late, especially low-energy injuries or purely ligamentous injuries. Severe sequelae such as post-traumatic osteoarthritis and foot deformities can create serious disability.

We must be attentive to the clinical and radiological signs of an injury to the Lisfranc joint and expand the study with weight-bearing radiographs or computed tomography (CT) scans.

Only in stable lesions and in those without displacement is conservative treatment indicated, along with immobilisation and initial avoidance of weight-bearing.

Through surgical treatment we seek to achieve two objectives: optimal anatomical reduction, a factor that directly influences the results; and the stability of the first, second and third cuneiform-metatarsal joints.

There are three main controversies regarding the surgical treatment of Lisfranc injuries: osteosynthesis versus primary arthrodesis; transarticular screws versus dorsal plates; and the most appropriate surgical approach.

The surgical treatment we prefer is open reduction and internal fixation (ORIF) with transarticular screws or with dorsal plates in cases of comminution of metatarsals or cuneiform bones.

Cite this article: EFORT Open Rev 2019;4:430-444. DOI: 10.1302/2058-5241.4.180076

Injury Pattern in Ligamentous Lisfranc Injuries in Competitive Athletes

BACKGROUND:

We report data on the largest cohort to date of patients who sustained a ligamentous Lisfranc injury during sport. To date, the prevalence of concurrent intercuneiform ligament injuries in the competitive athlete with subtle Lisfranc instability has not been reported.

METHODS:

Eighty-two patients (64 males, 18 females) sustained an unstable Lisfranc injury (49 left, 33 right) and met inclusion criteria. Injuries were classified as traditional dislocation (TRAD, first to second TMT ligament tear), medial column dislocation (MCD, second TMT, and medial-middle cuneiform ligament tear), or proximal extension dislocation (PE, first, second, and medial-middle cuneiform ligament tear) and the injury pattern confirmed at surgery. All athletes underwent open reduction with internal fixation (ORIF) of each unstable midfoot segment. Fisher exact tests and 2-tailed t tests were used to analyze statistical significance according to injury pattern, sport, gender difference, hindfoot angle alignment, and injured side ( P < .05).

RESULTS:

Average age of athletes was 21.0 ± 5.3 years old (range 12-40), and return to sports was 7.5 ± 2.1 months. Injury distribution was as follows: TRAD (n = 40), MCD (n = 17), and PE (n = 23). MCD trended toward a longer return to sport (8.4 ± 3.3 months, P = .074). Football was the most common sport at time of injury (n = 48). Wakeboard athletes (n = 5) were older (31.4 ± 3.2, P = .0002), and MCD tears were more prevalent among them ( P = .061). Basketball (n = 13) players were significantly younger (19.1 ± 2.5 years, P = .028) and returned to sports quicker (5.2 ± 0.7, P = .0002). Return to sport data indicated a typical population for athletes with Lisfranc injury in these sports.

CONCLUSION:

Proximal extension disruption (intercuneiform ligament tear) occurred in 50% of these low-energy Lisfranc athletic injuries. MCD and PE may be more prevalent than previously understood. This is the first study to document the extent, pattern, and prevalence of associated intercuneiform ligament tears in the competitive athlete with a low-energy subtle, unstable Lisfranc injury.

LEVEL OF EVIDENCE:

Level IV, retrospective case series.

Reliability, Surgeon Preferences, and Eye-Tracking Assessment of the Stress Examination of the Tarsometatarsal (Lisfranc) Joint Complex

The primary objective of this investigation was to determine the level of agreement and reliability of the stress examination of the Lisfranc tarsometatarsal joint complex. Secondary objectives were to determine surgeon preferences with respect to this testing and to use gaze recognition software to perform an eye-tracking assessment during the performance of the test. Twelve foot and ankle surgeons, 12 residents, and 12 students were shown 2 intraoperative fluoroscopic still images and 1 video of the stress examination of the tarsometatarsal joint complex using stress abduction of the forefoot on the rearfoot. Participants were asked to evaluate the result as being "positive" or "negative" for tarsometatarsal joint stability. The overall reliability of the interpretation of the stress examination was a kappa of 0.281 (surgeons 0.182; residents 0.423; students 0.256) indicating "fair" agreement. Survey results indicated wide variability in the perioperative preferences and protocols of surgeons dealing with the evaluation and treatment of the tarsometatarsal joint. Eye-tracking results also demonstrated variability in the anatomic structures of interest focused on during performance of this testing. The results of this investigation provide evidence of reliability well below what would be expected of a gold standard test during stress examination of the Lisfranc tarsometatarsal joint complex. These results indicate that future scientific endeavors are required to standardize the performance and interpretation of this testing.

Low-Energy Lisfranc Injuries in an Athletic Population: A Comprehensive Review of the Literature and the Role of Minimally Invasive Techniques in Their Management

Tarsometatarsal (TMT) joint complex injuries can be caused by either direct or indirect injuries. The Lisfranc joint represents approximately 0.2% of all fractures. Up to 20% of these injuries are misdiagnosed or missed on initial radiographic assessment; therefore, a high index of suspicion is needed to accurately diagnose TMT joint injuries and avoid the late sequelae of substantial midfoot arthrosis, pain, decreased function, and loss of quality of life. This review discusses the anatomy, diagnosis, and management of athletic Lisfranc injuries, including a description of the preferred minimally invasive surgical techniques used by the senior author of this article.

Imaging in Foot and Ankle Instability

This article reviews the imaging aspects relevant to ligamentous instabilities of the foot and ankle with a focus on MRI and ultrasound imaging. A pictorial review of the anatomy of the medial and lateral ankle ligaments, syndesmosis, spring ligament, Lisfranc complex, hallux sesamoid complex, and lesser toe plantar plate as seen on MRI is presented. Selected cases of ligamentous pathology relevant to foot and ankle instability are presented. The value of imaging in the assessment of foot and ankle instability is reviewed.

Management of Midfoot Fractures and Dislocations

PURPOSE OF REVIEW

To outline the classic and recent literature of midfoot fractures and dislocations.

RECENT FINDINGS

There has been an evolution of implant technology to include mini-fragment fixation, suture fixation, and staples. Their efficacy is still being elucidated in the literature. Also, there has been a recent push for primary fusion, which we will discuss. Open reduction internal fixation of the midfoot remains to be the gold standard treatment, to which all other treatments are compared. It remains to be seen if adjunct fixation techniques are efficacious enough to provide a good result. Further study is needed to determine which patients are likely to progress to debilitating arthrosis and require fusion.