Multi-segment foot kinematics during gait in children with spastic cerebral palsy.

BACKGROUND: Foot deformities (e.g. planovalgus and cavovarus) are very common in children with spastic cerebral palsy (CP), with the midfoot often being involved. Dynamic foot function can be assessed with 3D gait analysis including a multi-segment foot model. Incorporating a midfoot segment in such a model, allows quantification of separate Chopart and Lisfranc joint kinematics. Yet, midfoot kinematics have not previously been reported in CP. RESEARCH QUESTIONS: What is the difference in multi-segment kinematics including midfoot joints between common foot deformities in CP and typically-developing feet? METHODS: 103 feet of 57 children with spastic CP and related conditions were retrospectively included and compared with 15 typically-developing children. All children underwent clinical gait analysis with the Amsterdam Foot Model marker set. Multi-segment foot kinematics were calculated for three strides per foot and averaged. A k-means cluster analysis was performed to identify foot deformity groups that were present within CP data. The deformity type represented by each cluster was based on the foot posture index. Kinematic output of the clusters was compared to typically-developing data for a static standing trial and for the range of motion and kinematic waveforms during walking, using regular and SPM independent t-tests respectively. RESULTS: A neutral, planovalgus and varus cluster were identified. Neutral feet showed mostly similar kinematics as typically-developing data. Planovalgus feet showed increased ankle valgus and Chopart dorsiflexion, eversion and abduction. Varus feet showed increased ankle varus and Chopart inversion and adduction. SIGNIFICANCE: This study is the first to describe Chopart and Lisfranc joint kinematics in different foot deformities of children with CP. It shows that adding a midfoot segment can provide additional clinical and kinematic information. It highlights joint angles that are more distinctive between deformities, which could be helpful to optimize the use of multi-segment foot kinematics in the clinical decision making process.

Various Flexible Fixation Techniques Using Suture Button for Ligamentous Lisfranc Injuries: A Review of Surgical Options.

Contrary to Lisfranc joint fracture-dislocation, ligamentous Lisfranc injury can lead to additional instability and arthritis and is difficult to diagnose. Appropriate procedure selection is necessary for a better prognosis. Several surgical methods have recently been introduced. Here, we present three distinct surgical techniques for treating ligamentous Lisfranc employing flexible fixation. First is the "Single Tightrope procedure", which involves reduction and fixation between the second metatarsal base and the medial cuneiform via making a bone tunnel and inserting Tightrope. Second is the "Dual Tightrope Technique", which is similar to the "Single Tightrope technique", with additional fixation of an intercuneiform joint using one MiniLok Quick Anchor Plus. Last but not least, the "internal brace approach" uses the SwiveLock anchor, particularly when intercueniform instability is seen. Each approach has its own advantages and disadvantages in terms of surgical complexity and stability. These flexible fixation methods, on the other hand, are more physiologic and have the potential to lessen the difficulties that have been linked to the use of conventional screws in the past.

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.

Classification of the interosseous tarsometatarsal ligaments of the foot.

BACKGROUND: The aim of this study was to clarify the anatomical features of the interosseous tarsometatarsal ligaments of foot and to classify their types based on the combinations of their ligamentous components. METHODS: Fifty feet from 27 adult Korean cadavers were dissected. RESULTS: The interosseous tarsometatarsal ligaments were observed in the first, second, and third cuneometatarsal joint spaces. The interosseous tarsometatarsal ligament of the first cuneometatarsal space consistently connected the medial cuneiform and the second metatarsal, and was accompanied by one or two accessory ligaments above (34%) and/or below (6%) the Lisfranc ligament. The interosseous tarsometatarsal ligaments of the second and third cuneometatarsal joint spaces comprised seven and five components, and were classified into five and three types depending on the number and combination of the components, respectively. CONCLUSIONS: These results are expected to advance the current knowledge on the tarsometatarsal joint and provide helpful information for more accurate and successful diagnosis and treatment of lesions at this joint.

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.

Screw-plate fixation versus non-cannulated screw fixation for Lisfranc ligament injury: a 3-D finite element analysis / 中华创伤骨科杂志

Objective:To compare biomechanical stabilities between screw-plate fixation and non-cannulated screw fixation for Lisfranc ligament injury by a 3-D finite element analysis.Methods:A 3-D model of a healthy foot was developed from computed tomography images. The 1st and the 2nd dorsal tarsometatarsal ligaments and Lisfranc ligament were cut in the 3-D model of a healthy foot to establish a Lisfranc ligament injury model, in which screw-plate fixation (with 2 locking plates and 8 standard screws and one non-cannulated screw) and non-cannulated screw fixation (with 3 non-cannulated screws) for Lisfranc ligament injury were simulated respectively. Finite element analyses were carried out by Abaqus 6.14 software after loads were added in the 3-D models of screw-plate fixation and non-cannulated screw fixation for Lisfranc ligament injury. The overall stress-strain nephogram, the stress distribution and displacement of the foot bone, and the stress distribution on the internal fixation system were compared between the 2 kinds of models.Results:Under the same load, the stress of the whole screw-plate fixation was concentrated on the fixators, and the stress of the non-cannulated screws was also greater than that of the bones. In both models, the strain of the whole foot led to arch collapse, especially in the medial column. The maximum stress on the screw holes in the medial and middle columns in the screw-plate fixation model was 39.91 MPa, smaller than that in the non-cannulated screw fixation model (53.13 MPa). The relative displacement of the first metatarsal joint in the screw-plate fixation model was 8.515 × 10 -1 mm, much greater than that in the non-cannulated screw fixation model (3.893 × 10 -1 mm). Stress concentration was observed in both models. The stress of the screw-plate system was concentrated on the fibular side of the middle section of the plate used to fix the first tarsometatarsal joint, decreasing towards both ends. The maximum stress of the non-cannulated screws was located in the middle of the medial column screw for fixation of the first tarsometatarsal joint, significantly greater than those of the both ends. The maximum stress of the screw-plate system was 239.5 MPa, smaller than that of the non-cannulated screws (256.8 MPa). Conclusions:Non-cannulated screw fixation demonstrates a greater biomechanical stability for Lisfranc ligament injury than screw-plate fixation. However, the former may have a higher risk of screw breakage because it bears a greater stress.

Reliability of measurements assessing the Lisfranc joint using weightbearing computed tomography imaging.

INTRODUCTION: Subtle Lisfranc joint injuries remain challenging to diagnose in clinical practice. Although of questionable accuracy, bilateral weightbearing radiographs are considered the current gold standard to assess these injuries. However, weightbearing computed tomography (WBCT), which provides clearer visualization of bony landmarks, can also be used for evaluation. This study aims to design a protocol that reliably measures the distance between the medial cuneiform (C1) and second metatarsal (M2) to assess the Lisfranc joint using WBCT imaging. METHODS: Two unique methods of measuring the C1-M2 distance were designed that localize the center of the interosseous Lisfranc ligament (ILL, reference point). This reference point was located by (I) measuring a specific distance at the M2 base, or (II) approximating from nearby bony landmarks, on both axial (Ax) and coronal (Cor) WBCT images. Four parameters (I-Ax, I-Cor, II-Ax, and II-Cor) were evaluated for each of 96 specimens. Measurements were recorded by three independent observers and repeated for inter- and intra-observer agreement. RESULTS: In total, 96 patient image series were included and assessed in our study with an average age of 46 (19-66, SD 16.1) and average BMI of 25.8 (17.8-30.5, SD 4.3). I-Ax showed excellent agreement for intra-observer evaluation (R = 0.802) and good agreement for inter-observer evaluation (R = 0.727). I-Cor demonstrated excellent inter- (R = 0.814) and intra-observer (R = 0.840) agreement. Good agreement was found for both II-Ax and II-Cor for both intra- (R = 0.730, R = 0.708) and inter-observer (R = 0.705, R = 0.645) evaluation. CONCLUSION: Measuring the C1-M2 joint space with coronal WBCT imaging through a protocol that localizes the ILL is reproducible, simple, and can potentially be utilized clinically to evaluate the Lisfranc joint.

Using area and volume measurement via weightbearing CT to detect Lisfranc instability.

Weightbearing CT (WBCT) allows evaluation of the Lisfranc joint under physiologic load. We compared the diagnostic sensitivities of one-dimensional (1D) distance, two-dimensional (2D) area, and three-dimensional (3D) volumetric measurement of the injured Lisfranc joint complex (tarsometatarsal, intertarsal, and intermetatarsal) on WBCT among patients with surgically-confirmed Lisfranc instability. The experimental group comprised of 14 patients having unilateral Lisfranc instability requiring operative fixation who underwent preoperative bilateral foot and ankle WBCT. The control group included 36 patients without foot injury who underwent similar imaging. Measurements performed on WBCT images included: (1) Lisfranc joint (medial cuneiform-base of second metatarsal) area, (2) C1-C2 intercuneiform area, (3) C1-M2 distance, (4) C1-C2 distance, (5) M1-M2 distance, (6) first tarsometatarsal (TMT1) angular alignment, (7) second tarsometatarsal (TMT2) angular alignment, (8) TMT1 dorsal step off distance, and (9) TMT2 dorsal step-off distance. In addition, the volume of the Lisfranc joint in the coronal and axial plane were calculated. Among patients with unilateral Lisfranc instability, all WBCT measurements were increased on the injured side as compared to the contralateral uninjured side (p values: <.001-.008). Volumetric measurements in the coronal and axial plane had a higher sensitivity (92.3%; 91.6%, respectively) and specificity (97.7%; 96.5%, respectively) than 2D and 1D Lisfranc joint measurements, suggesting them to be the most accurate in diagnosing Lisfranc instability. The control group showed no difference in any of the measurements between the two sides. WBCT scan can effectively differentiate between stable and unstable Lisfranc injuries. Lisfranc joint volume measurements demonstrate high sensitivity and specificity, suggesting that this new assessment has high clinical implications for diagnosing subtle Lisfranc instability.

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.

Deep Peroneal Neurectomy for Midfoot Arthritis.

Osteoarthrosis of the tarsometatarsal joint (TMTJ) and naviculocuneiform joint (NCJ) is a common pathology treated by foot and ankle specialists. Arthrodesis is the most widely accepted surgical treatment. Patients that are not candidates for arthrodesis are often left without surgical treatment options. Neurectomy has been described for treatment of upper extremity joint arthrosis but has not been well described in the foot. The deep peroneal nerve innervates the first, second, third TMTJs and NCJ. We present a retrospective case series on the outcomes of patients treated with deep peroneal neurectomy for TMTJ and NCJ arthrosis (N = 34 feet in 26 patients). The median postoperative American Orthopedic Foot and Ankle Society midfoot score was 53 (range 16-75) points. Twenty two (85%) of 26 patients stated that their expectations were met as a result of the deep peroneal neurectomy procedure, and 20 (77%) of 26 patients stated that they would have deep peroneal neurectomy for their symptoms again. There were recurrent symptoms prompting patients to seek additional treatment in 7 (21%) of 34 feet. Recurrent pain is also documented in hand denervation studies and the physiologic explanation remains unclear. Our results suggest that deep peroneal neurectomy is an effective treatment option for TMTJ and NCJ arthritis and may be particularly helpful in patients that are poor candidates for arthrodesis.

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.

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.

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.

[Selective tarsometatarsal arthrodesis for old Lisfranc injury].

Objective: To discuss the methods and clinical outcomes of selective tarsometatarsal (TMT) arthrodesis for old Lisfranc injury. Methods: The clinical data of 36 cases with old Lisfranc injury treated by selective arthrodesis from January 2010 to October 2016 in the Department of Orthopedics in Shanghai Sixth People's Hospital were analyzed retrospectively. There were 16 males and 20 females in this group with a mean age of (40±6) years. The information of pre-operative and post-operative X-ray, American Orthopaedics Foot and Ankle Society (AOFAS) midfoot score and pain Visual Analogue Scale (VAS) score was collected. The complications were also recorded. The pre- and post-operative data were compared with t test. Results: The 36 patients got a follow-up for at-least 2 years (averaged (4.3±1.6) years, ranged from 2 to 8 years). The post-operative AOFAS midfoot score was improved from (44±7)(28-60) to (83±7)(76-97)(t=-37.1, P<0.05), and the VAS score decreased from (6.3±2.5)(5-9) to (1.6±1.3)(0-3)(t=23.7, P<0.05). Implant breakage occurred in two patients and the symptom was relieved after the removal of implants. Conclusion: The selective TMT arthrodesis for old Lisfranc injury may relieve the symptoms, improve the function and life quality of patients by restoring the medial arch and midfoot and forefoot alignment.

The computed tomographybased anatomy of the ossa cuneiformia.

There is a lack of basic anatomic information regarding the ossa cuneiformia. The aim of the present descriptive study was the detailed evaluation of the anatomy of the ossa cuneiformia. We analyzed 100 computer tomography scans of feet without deformities or previous trauma. The length, height and width of each cuneiforme and their articular surfaces were assessed. We itemized the data to gender differences and to foot length. The medial cuneiforme os had a length of 24.0 mm ± 2.4 (mean ± standard deviation), a width of 17.3 mm ± 2.8 and a height of 28.0 mm ± 3.4. The respective values for the intermediate cuneiforme were 18.2 mm ± 2.1, 15.8 mm ± 2.1 and 22.5 ± 2.2 and for the lateral cuneiforme 26.4 mm ± 2.7, 17.2 mm ± 2.9 and 22.8 mm ± 2.9. We found statistical relevant differences regarding gender and foot length subgroups whereas not for all parameters. The present study illustrates basic anatomic data regarding the ossa cuneiformia. This information might be helpful for implant design and placement during midfoot surgery.

Variations of the plantar tarsometatarsal ligaments.

This study investigated the morphological variations of the plantar tarsometatarsal ligaments of the foot by classifying them based on their ligamentous components. Fifty embalmed feet from 27 adult Korean cadavers were used. The plantar tarsometatarsal ligaments comprised nine components (medial cuneiform-first metatarsal, pCn1-M1; medial cuneiform-second metatarsal, pCn1-M2; medial cuneiform-second and third metatarsals, pCn1-M2,3; median cuneiform-second metatarsal, pCn2-M2; lateral cuneiform-third metatarsal, pCn3-M3; lateral cuneiform-fourth metatarsal, pCn3-M4; lateral cuneiform-third and fourth metatarsals, pCn3-M3,4; cuboid-fourth metatarsal, pCb-M4; and cuboid-fifth metatarsal, pCb-M5). pCn1-M2 was newly observed in the present study. The number of the bands composing the ligament was one in the pCn1-M2, pCn2-M2, pCn3-M3, and pCn3-M4 components, and one or two in the pCn1-M1, pCn1-M2,3, pCn3-M3,4, pCb-M4, and pCb-M5 components. The plantar tarsometatarsal ligaments were classified into five types based on the combination of their components. The pCn1-M1, pCn1-M2,3, and pCn2-M2 components were consistently observed in types I-IV (88%), along with pCn3-M3,4 in type I, pCn3-M4 and pCb-M5 in type II, and pCn3-M3 in type IV. In type V (12%), the pCn1-M1 and pCb-M5 components were consistently present. Improved comprehension of the variations in plantar tarsometatarsal ligament anatomy is expected to help diagnose diverse injuries to this region, better understand the structural pathomechanism of the injuries, and contribute to successful treatment. Clin. Anat. 32:699-705, 2019. © 2019 Wiley Periodicals, Inc.