Factors Influencing PROMIS Scores and Patient Reported Outcomes Following Surgical Intervention of Isolated Lisfranc Injury: Minimum 2 Year Follow-up

Lisfranc injuries are rare but significant foot injuries, as they often result from polytrauma patients, and are often misdiagnosed, which further complicate their evaluation and contribute to their propensity towards disability. It is recommended that, on diagnosis, Lisfranc injuries be treated as soon as possible to decrease the risk of future chronic pain, disability, or osteoarthritis. Our study evaluated patients who completed the patient reported outcome measurement information systems (PROMIS) along with the foot function index (FFI) following operative fixation for Lisfranc injury. Fifty-one patients between 2010 and 2020 met inclusion criteria and were selected for this study, with completion. Utilizing the electronic medical record (EMR), patient charts were reviewed to obtain basic patient demographic information and comorbidities. Operative reports were reviewed to determine which procedure was performed for definitive fixation. Primary arthrodesis was associated with a significant decrease in complication rates (p = .025) when compared to ORIF. Females, arthrodesis, and procedures using a home run (HR) screw were independent risk factors for significantly higher reports of PROMIS pain interference. Arthrodesis also was associated with lower PROMIS pain interference scores. Arthrodesis and males exhibited higher scores in all FFI categories. Our results provide evidence that patient reported outcomes following Lisfranc surgery reported via PROMIS, FFI and VAS scores are independently influenced by patient demographics, comorbidities, and surgical variables. Analysis of potential associations between these patient characteristics and PROMIS and FFI scores provides evidence for physicians to manage patient expectations prior to operative treatment of a nonpolytraumatic Lisfranc injury.

Open vs Minimally Invasive Resection of the First Metatarsocuneiform Joint: An Anatomical Study

BACKGROUND

The modified Lapidus arthrodesis is a standard procedure to correct middle to severe hallux valgus (HV) deformities. Recently, minimally invasive techniques of first metatarsocuneiform joint (MCJ) resection using a Shannon burr were described. The primary goal of this study is to compare the anatomical efficacy and safety of first MCJ resection using a straight 2 × 13-mm Shannon burr and minimally invasive technique (MIS) vs an open technique using an oscillating saw.

METHODS

Ten pairs of fresh frozen cadaveric feet were randomly assigned to open or MIS first MCJ resection with subsequent systematic dissection. For the MIS procedure, a dorsomedial approach was used and for the open procedure a medioplantar approach was used. Cartilage removal was investigated by analyzing standardized scaled photographs of the resected articular surfaces with ImageJ software. Nearby structures at risk were analyzed for iatrogenic violation: tibialis anterior (TA), extensor hallucis longus (EHL) and peroneus longus (PL) tendons, and the Lisfranc ligament complex (LLC).

RESULTS

In the MIS group, the median cartilage resection was 85.9% at the cuneiform and 85.6% at the metatarsal bone compared to 100% cartilage resection in open technique (P < .01). Iatrogenic damage of the LLC, EHL, and TA tendons was not found in any group. The PL tendon was thinned out (<25% of tendon thickness) in 4 cases (40%) in the open group and in 1 case (10%) in the MIS group. A safe zone of 3.0 mm between the articular surface of the cuneiform bone and the LLC was identified, which can be resected without putting the LLC at risk when performing lateral-based wedge resections.

CONCLUSION

In this cadaver study with the procedures performed by an experienced foot and ankle surgeon, and using 2 different surgical approaches, we found general parity between the Shannon burr MIS technique vs oscillating saw open technique techniques with more risk to the PL with our open technique and approximately 15% less cartilage resection with our MIS technique.

LEVEL OF EVIDENCE

Level V, cadaver study.

Defining Reference Values for the Normal Adult Lisfranc Joint Using Weightbearing Computed Tomography

The uninjured contralateral feet of consecutive patients undergoing cone-beam weightbearing computed tomography for acute Lisfranc injury between July 2017 and October 2019 were retrospectively analyzed. Of these, any cases with history or radiological evidence of trauma to the Lisfranc interval were excluded. The area of the non-weightbearing (NWBA) and weightbearing (WBA) Lisfranc joint was calculated (in mm²) using a novel technique. Area difference (AD) was calculated as WBA-NWBA. Area ratio (AR) was calculated as WBA/NWBA. A subset of cases was double-measured by 2 technologists to evaluate inter- and intraobserver variability. A total of 91 patients aged 15 to 74 years were included in the study. The measurement technique was reproducible with excellent intraobserver correlation (intraclass correlation coefficient [ICC]: 0.998, 95% confidence interval [CI]: 0.996-0.999) and high interobserver correlation (ICC: 0.964, CI: 0.939-0.979). The median NWBA was 83 (range 52-171) and median WBA was 86 (range 52-171). Median AD was 1 mm² (range -3 to 10) and median AR was 1.01 (range 0.96-1.11). No significant difference was identified in AD or AR when adjusted for age, gender, patient-weight or weight put through the foot. Both AD and AR distributions were highly skewed toward 0 and 1, respectively. Based on 95% CI, normal reference range for AD is -1 to 7 mm² and for AR is 0.98 to 1.09. Absolute area of the Lisfranc joint is highly variable between individuals. The Lisfranc joint is rigid with little to no physiologic widening in most subjects. The normal upper limit of widening of the Lisfranc area on weightbearing was 9%. Differences in age, sex, patient-weight or weight put through the foot were not significantly associated with the extent of joint widening.

Lisfranc complex injuries management and treatment: current knowledge

Lisfranc complex injuries are a spectrum of midfoot and tarsometatarsal (TMT) joint trauma, more frequent in men and in the third decade of life. Depending on the severity of the trauma can range from purely ligamentous injuries, in low-energy trauma, to bone fracture-dislocations in high-energy trauma. A quick and careful diagnosis is crucial to optimize management and treatment, reducing complications and improving functional outcomes in the middle and long-term. Up to 20% of Lisfranc fractures are unnoticed or diagnosed late, above all low-energy trauma, mistaken for simple midfoot sprains. Therefore serious complications such as post-traumatic osteoarthritis and foot deformities are not uncommon. Clinically presenting with evident swelling of the midfoot and pain, often associated with joint instability of the midfoot. Plantar region ecchymosis is highly peculiar. First level of examination is X-Ray performed in 3 projections. CT scan is useful to detect nondisplaced fractures and minimal bone sub-dislocation. MRI is the gold standard for ligament injuries. The major current controversies in literature concern the management and treatment. In stable lesions and in those without dislocation, conservative treatment with immobilization and no weight-bearing is indicated for a period of 6 weeks. Displaced injuries have worse outcomes and require surgical treatment with the two main objectives of anatomical reduction and stability of the first three cuneiform-metatarsal joints. Different surgical procedures have been proposed from closed reduction and percutaneous surgery with K-wire or external fixation (EF), to open reduction and internal fixation (ORIF) with transarticular screw (TAS), to primary arthrodesis (PA) with dorsal plate (DP), up to a combination of these last 2 techniques. There is no superiority of one technique over the other, but what determines the post-operative outcomes is rather the anatomical reduction. However, the severity of the injury and a quick diagnosis are the main determinant of the biomechanical and functional long-term outcomes.

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.

Clinical outcomes of Tightrope system in the treatment of purely ligamentous Lisfranc injuries

Background

Purely ligamentous Lisfranc injuries are mainly caused by low energy damage and often require surgical treatment. There are several operative techniques for rigid fixation to solve this problem clinically. This study evaluated the effect of using the Tightrope system to reconstruct the Lisfranc ligament for elastic fixation.

Methods

We retrospectively analyzed 11 cases with purely ligamentous Lisfranc injuries treated with the Tightrope system from 2016 to 2019, including 8 male and 3 female. X-ray was performed regularly after operation to measure the distance between the first and second metatarsal joint and the visual analogue scale (VAS) score was used to evaluate pain relief. American orthopedic foot & ankle society (AOFAS) and Maryland foot score were recorded at the last follow-up.

Results

The average follow-up time was 20.5 months (range, 17–24). There was statistically significant difference in the distance between the first and second metatarsal joint and VAS score at 3 months, 6 months, and the last follow-up when compared with preoperative values (P < 0.05).Mean of postoperative AOFAS mid-foot scale and Maryland foot score were 92.4 ± 4.3, 94.1 ± 3.5, respectively. The Tightrope system was not removed and the foot obtained better biomechanical stability. No complications occurred during the operation.

Conclusion

Tightrope system in the treatment of purely ligamentous Lisfranc injuries can stabilize the tarsometatarsal joint and achieve satisfactory effect.

Screw in Lisfranc Ligament

Background. Injury to the Lisfranc interosseous ligament is currently managed with a screw. However, this can potentially further disrupt the ligament. The objective of this study was to observe the proximity of the screw or disruption it can cause at the ligament attachment sites. Methods. Twenty-three feet were studied. A 40-mm, 4.0, partially threaded, cannulated screw was inserted from the base of the second metatarsal into the medial cuneiform. The relationship of the ligament attachment sites to the screw hole were measured. Results. The screw hole contacted at least 1 of the ligament attachment sites in 20 of the 23 feet. The screw hole fully penetrated it in 7 feet, partially disrupted it in 4 feet, and had less than or equal to 1 mm of contact in 9 feet. There was no contact with either of the attachment sites in 3 feet, with an average distance of 1.5 mm separating them. Conclusion. Our results show the proximity of the ligament to the screw and the disruption that can result from its insertion. This is clinically relevant as some amount ligamentous disruption is likely to occur with insertion of the "Lisfranc screw," which may interfere with its healing process.Levels of Evidence: Level V: Expert opinion includes case reports and technique tips.

Suture Button vs Conventional Screw Fixation for Isolated Lisfranc Ligament Injuries

BACKGROUND

Suture buttons have been used for isolated Lisfranc ligament (ILL) fixation. However, no study has reported on its clinical and radiologic outcomes.

METHODS

In this retrospective comparative study, patients with ILL injuries were divided into 2 groups according to the treatment method: 32 conventional screw group and 31 suture button group. The clinical and radiologic outcomes at preoperation, 6 months and 1 year postoperation, and last follow-up period were measured. Plantar foot pressure was measured at postoperative month 6 months. Postoperative complications at the last follow-up were evaluated.

RESULTS

The suture button group showed better American Orthopaedic Foot & Ankle Society midfoot scale (P < .001) and visual analog scale (P < .001) scores compared with the conventional screw fixation group at the postoperative month 6 period before screw removal. However, no significant difference in clinical outcome between the 2 groups was found at postoperative year 1 or last follow-up. No differences in radiologic outcomes were found between the 2 groups. Plantar foot pressure was significantly elevated in the conventional screw group at the great toe and first metatarsal head area compared with the contralateral foot just before screw removal. Recurrent Lisfranc joint diastasis was found in a single case in the conventional screw group and 2 cases in the suture button group.

CONCLUSION

Suture button fixation in the treatment of ILL injuries may provide comparable fixation stability and clinical outcome with conventional screw fixation in the early postoperative period.

LEVEL OF EVIDENCE

Level III, retrospective case-control study, therapeutic.

[Short-term effectiveness of Endobutton plate in reconstruction of Lisfranc ligament]

Objective

To observe the short-term effectiveness of Endobutton plate in the reconstruction of Lisfranc ligament in tarsometatarsal joint injury.

Methods

Between March 2015 and July 2018, 18 patients with tarsometatarsal joint injuries were treated with Lisfranc ligament reconstruction by Endobutton plate. There were 12 males and 6 females with an average age of 32.5 years (range, 16-55 years). The causes of injury were traffic accident in 8 cases, falling from height in 3 cases, crushing by a heavy objective in 4 cases, and spraining in 3 cases. There were 10 cases of Myerson type A, 4 of type B1, 2 of type B2, 1 of type C1, and 1 of type C2. The interval between injury and operation ranged from 3 to 9 days (mean, 4.9 days). X-ray examination was performed regularly after operation to measure the distance between the first and the second metatarsal joints, and the visual analogue scale (VAS) score was used to evaluate the pain relief. At last follow-up, the reduction of tarsometatarsal joint was evaluated by measuring and comparing the height of the affected and healthy arches. The foot function was evaluated according to the American Orthopaedic Foot and Ankle Society (AOFAS) score.

Results

The average follow-up time was 15.8 months (range, 10-28 months). All incisions healed by first intention. X-ray reexamination showed that there was no screw loosening or plate fracture. There were significant differences in the distance between the first and the second metatarsal joints and VAS score at 3 months after operation, before removal of the internal fixator, and at last follow-up when compared with preoperative values ( P<0.05). There was no significant difference between the time points after operation ( P>0.05). At last follow-up, there was no significant difference in the arch height between affected foot [(5.3±0.2) mm] and healthy foot [(5.4± 0.3) mm] ( t=1.798, P=0.810). The AOFAS score of foot function was 89.5±7.3 with excellent in 12 cases, good in 4 cases, and fair in 2 cases. The excellent and good rate was 88.9%.

Conclusion

The reconstruction of Lisfranc ligament with Endobutton plate can stabilize the tarsometatarsal joint and achieve satisfactory foot function at early stage.

Morphological features of the lateral plantar ligament of the transverse metatarsal arch

The aim of this study was to elucidate the morphological characteristics of the lateral Lisfranc ligament in a large sample. This investigation examined 100 legs from 50 cadavers. Each of the lower limbs was dissected to identify the plantar aspect of the transverse metatarsal arch, and morphological characteristics of the lateral plantar ligament were assessed, including the length, width, and thickness of the fiber bundles. The majority of plantar ligaments originated from the base of M5 and the plantar aspect of the lateral cuneiform (LC). The lateral plantar ligament could be classified into three types: Type I, a band-like fiber bundle originating from the base of M5 to the LC (41%); Type II, originating from the base of M5 and the plantar aspect of LC and mostly connected the blending the fiber bundles of the tibialis posterior (TP) and long plantar ligament (LPL) (21%); and Type III, with no ligaments originating from the base of M5 and plantar aspect of the LC (38%). The morphological characteristics of Type I lateral plantar ligament were as follows: length, 31.8 ± 3.7 mm; width, 2.3 ± 1.0 mm; and thickness, 0.2 ± 0.3 mm. The morphology of the lateral plantar ligament showed variation, originating from the base of M5 and the plantar aspect of LC most commonly, but this was not the case in 38% of limbs. The findings suggest that the lateral plantar ligament might play a role in the transverse tarsal arch, indicating a cooperative mechanism with the TP and LPL.

Dynamic MR imaging analysis of instability in the injured Lisfranc joint with an MRI-compatible foot stressor device

PURPOSE

To evaluate the applicability of an MRI-compatible foot stressor device in patients with image-proven or clinically suspected Lisfranc joint injuries.

METHOD

This prospective study evaluated Lisfranc joint injury by utilizing a joint-specific, stress device that was engineered to replicate weightbearing and physical examination maneuvers. Sixteen patients with either clinically suspected or image-proven Lisfranc joint injuries were recruited from September 2018 to November 2019 (9 men, 7 women; mean age, 39.3 years; age range, 14-68 years). Resting and stressed MR sequences of the injured and non-injured feet were obtained. Measured values for Lisfranc interval widths, dorsal tarsometatarsal subluxations, and lambda-angles were subtracted between the stressed and resting images to calculate net stress-induced changes. A graded injury schema was used to measure significance.

RESULTS

The foot stressor device reliably generated stress-induced changes in the Lisfranc joint during dynamic MRI examination. All morphologically abnormal ligaments on resting images demonstrated stress-induced changes, whereas all morphologically normal ligaments lacked evidence of instability. More severely injured Lisfranc ligaments allowed greater Lisfranc joint widening (IOL, p < 0.001; PCL, p < 0.001; DCL, p < 0.001). More highly graded DCL injuries allowed greater dorsal TMT subluxation when present (p < 0.001). Angular gain in the midfoot (lambda-angle) correlated with the graded IOL score (p < 0.001). Acute-to-subacute injuries demonstrated greater inducible changes than chronic injuries (p = 0.047). Seven patients underwent surgery and nine patients received physical therapy.

CONCLUSIONS

Stress-induced changes in the midfoot provided information on the degree of ligament pathology and associated joint instability in Lisfranc joint injuries.

Morphological characteristics of the Lisfranc ligament

BACKGROUND

This study aimed to clarify the morphological characteristics of the Lisfranc ligament and the cuneiform 1-metatarsal 2&3 plantar ligament (CMPL).

METHODS

Forty legs from 20 cadavers were examined. Classification proceeded according to the number of fiber bundles in the Lisfranc ligament and the CMPL. Morphological features measured were fiber bundle length, width, thickness, and angle.

RESULTS

In Type I-a, the Lisfranc ligament and the CMPL were a single fiber bundle; in Type I-b, the Lisfranc ligament was a single fiber bundle, and the CMPL was two fiber bundles; in Type II-a, the Lisfranc ligament was a two fiber bundle, and the CMPL was a single fiber bundle; in Type II-b, the Lisfranc ligament and the CMPL were two fiber bundles; in Type III-a, the Lisfranc ligament was three fiber bundles, and the CMPL was a single fiber bundle; in Type III-b, the Lisfranc ligament was three fiber bundles, and the CMPL was two fiber bundles; in Type IV, the Lisfranc ligament and the CMPL could not be separated. Type I-a was seen in 37.5%, Type I-b in 10%, Type II-a in 30%, Type II-b in 7.5%, Type III-a in 7.5%, Type III-b in 2.5%, and Type IV in 5%. The Lisfranc ligament was significantly larger than the CMPL in total fiber bundle width, total fiber bundle thickness, and total fiber bundle angle.

CONCLUSION

The Lisfranc ligament had up to 3 fiber bundles and the CMPL had one or two fiber bundles; classifications were four types and two subgroups.

Ultrasound as a Diagnostic Tool in the Assessment of Lisfranc Joint Injuries

OBJECTIVES

Ligamentous Lisfranc injuries are frequently overlooked because of subtle clinical presentations and diagnostic difficulties. The dorsal Lisfranc ligament (DLL) is easily visualized with ultrasound (US), which can provide quick, cost-effective diagnoses of disorders but is not considered standard clinical practice. This study sought to compare DLL measurement accuracy between US and cadaveric dissection.

METHODS

Ultrasound images of 22 embalmed cadaveric feet were obtained with an M-Turbo US machine and a 6-13-MHz linear array (FUJIFILM SonoSite, Inc, Bothell, WA). Images were measured in the US unit and again with ImageJ software (National Institutes of Health, Bethesda, MD). Specimens were dissected, and DLL morphologic characteristics were recorded.

RESULTS

Twenty-two specimens were scanned, however 4 were excluded, leaving a sample of 11 male and 7 female cadaveric specimens (mean age ± SD, 80.3 ± 14.03 years). The DLL length differences between SonoSite (8.39 ± 1.27 mm) and ImageJ (8.25 ± 1.84 mm) were not significant (P > .05). Both US DLL measurements significantly differed from the gross dissection measurement (10.8 ± 1.85 mm; P < .001). The morphologic characteristics of the DLL at dissection were consistent. Overall, 70% to 80% of the ligament length was represented by US compared to dissection. The dorsal joint space did not differ significantly between SonoSite (2.19 ± 0.49 mm) and ImageJ (2.05 ± 0.52; P > .05). Both US measurements were also significantly larger than dissection measurements (1.04 ± 0.24; P < .001). Intraclass correlation coefficients indicated good reliability for the DLL length (0.835) and moderate reliability for the dorsal joint space (0.714).

CONCLUSIONS

The DLL is underrepresented but easily distinguished by US, demonstrating its utility in Lisfranc injury diagnosis. Thus, we propose a 4-component assessment involving US, which may provide more rapid, cost-effective diagnoses of subtle Lisfranc injuries.

Evaluation of the Area of the Lisfranc Ligament Damaged by Screw Fixation

BACKGROUND

A cannulated screw is currently the standard fixation method to reduce and stabilize diastasis at the lisfranc joint following injury. Currently, there is no literature examining the area of the lisfranc ligament damaged by screw placement. The objective of this investigation is to define the area of the ligament damaged by fixation with a 3.5-mm cannulated screw.

MATERIALS AND METHODS

Twelve cadaveric feet were dissected to identify the Lisfranc ligament metatarsal insertion site and origin on the medial cuneiform. A 3.5-mm cannulated screw was then passed over the course of the ligament and removed. The Lisfranc joint was then dissected to measure the dimensions of the ligament and damage from screw passage at the origin and insertion using imaging software.

RESULTS

Mean injury area on the metatarsal was 3.49 mm² and the area of injury for the cuneiform was 3.33 mm². The mean percent of the area damaged was calculated to be 1.75% and 2.43% at the cuneiform and metatarsal, respectively.

CONCLUSION

A proportionally small area of the Lisfranc ligament is disrupted following screw fixation, but the implications of this on ligament healing and outcomes remain to be elucidated.

LEVELS OF EVIDENCE

Level V: Cadaveric study.

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.

Evaluation of dorsal Lisfranc ligament deformation with load using ultrasound imaging

BACKGROUND

Research findings have linked dorsal Lisfranc ligament (dLL) rupture to complete Lisfranc ligament complex rupture; identifying deformation characteristics of the dorsal Lisfranc ligament alone may be helpful in diagnosing complete ligament rupture. The goal of the present study was to assess the deformation characteristics of the asymptomatic dLL using physiologically relevant stress/loads in a clinical setting and to discern normative dLL parameters.

METHODS

Unilateral dLL measurements were taken from 50 healthy volunteers, using sonographic imaging under three different stress/load conditions. Stress/load was applied using the individuals' bodyweight (low-seated; medium-bilaterally equal weight bearing in standing; and high-single leg standing). Digital images of the dLL captured using ultrasound were visualized to determine the dLL length. One-way repeated measures ANOVA was used to assess changes in the dLL length with load.

RESULTS

The average dLL elongation, as percent resting length change, was 8.76% between seated and single leg standing positions. Most of the dLL elongation (6.26%) occurred between seated and bilateral standing.

CONCLUSIONS

The deformation and role of the dorsal Lisfranc ligament can be observed using sonographic imaging resulting from physiological loading in the clinical setting.

CLINICAL RELEVANCE

These deformation parameters can be used to generate normative data for diagnostic purposes.

MR Imaging Evaluation of the Lisfranc Ligament in Cadaveric Feet and Patients With Acute to Chronic Lisfranc Injury

BACKGROUND

Magnetic resonance (MR) imaging is known to be useful to demonstrate Lisfranc ligament injury. There are few studies that report differences in MR imaging findings of acute or chronic Lisfranc ligament injuries. We applied oblique MR imaging planes parallel to the Lisfranc ligament for better visualization of the entire course of the ligament and assessed the detailed MR imaging appearances of the Lisfranc ligament in cadavers and patients with presumed Lisfranc injuries.

METHODS

Twelve preserved cadaveric feet were examined using a small-diameter surface coil. Long axis, oblique sagittal, and oblique short axis cross sections parallel to the Lisfranc ligament, dorsal ligament, and plantar ligament were obtained. Twenty-six MR examinations from 23 patients with suspected Lisfranc joint injuries were evaluated.

RESULTS

In the cadaveric study, the Lisfranc ligament was satisfactorily visible along its entire course in a single slice on long axis and oblique sagittal MR images. The dorsal ligament and the plantar ligament were visible separately from the Lisfranc ligament in oblique sagittal and oblique short axis planes. In the patient study, 11 MR examinations led to diagnoses of complete tears of the Lisfranc ligament that were acute injuries (3-21 days after trauma) mostly associated with disruption of the dorsal and plantar ligaments. Nine studies led to diagnoses of incomplete tears of the Lisfranc ligament that were chronic injuries (2-14 months after trauma). Recovery of the continuity of the disrupted ligament was observed in 3 patients.

CONCLUSION

MR imaging demonstrated the integrity of the ligaments and was useful for diagnosing an acute Lisfranc injury. Fibrous healing of the torn ligament was observed in a chronic injury.

Three-dimensional, digital, and gross anatomy of the Lisfranc ligament

BACKGROUND

There are inconsistencies in the descriptive anatomy of the Lisfranc ligament. No information is available on orientation of fibers or presence of bundles, nor are there 3-dimensional anatomic data on the ligaments or their attachments. This study assessed the 3-dimensional anatomy of the Lisfranc ligament and its attachment sites.

METHODS

A total of 37 cadaver feet were dissected to expose the ligament attachments at the Lisfranc joint. The Lisfranc ligament and plantar ligament attachments were outlined separately and then removed with the attachment outlines preserved. A 3-dimensional digitizer was used to digitize bony and articular surfaces, as well as ligament attachment sites, at approximately 1 mm intervals; the positional accuracy was 0.23 mm. The surface areas of the entire bone, articular regions, and Lisfranc and plantar ligament attachment regions were determined and anatomic details were noted.

RESULTS

The Lisfranc ligament had a single bundle in 73% of the specimens and 2 bundles in 27%. Both variations had a single attachment to the second metatarsal (M2; mean attachment surface area, 135 mm(2)). The single-bundle variation attached to the medial cuneiform (C1; mean attachment surface area, 140 mm(2)). The plantar ligament, C1-M2-M3, attached to the anterior plantar surface of the lateral aspect of C1 (mean attachment surface, 64 mm(2)) and had attachment sites at the bases of M2 and M3. Its fibers ran anteriorly and inferiorly, with attachments to the proximal inferomedial aspect of M2 (mean attachment surface, 63 mm(2)) and fibers extending to a smaller attachment at the plantar aspect of M3 (mean attachment surface area, 26 mm(2)).

CONCLUSION

The Lisfranc ligament is variable in anatomy and can have a single- or double-bundle arrangement. Its area of attachment is larger than that of the plantar ligament.

CLINICAL RELEVANCE

Anatomic descriptions of location, dimensions, and variability in the position and surface area of the ligament attachment sites and of orientation of the bundles provide information for future attempts at repair or reconstruction of the Lisfranc ligament.