Medial Cuneiform Research Articles

Vascular Anomalies in the Course and Branching Pattern of the Dorsalis Pedis Artery: A Case Report

The dorsalis pedis artery (DPA) vascularizes most of the dorsum of the foot where it provides several branches. During a scheduled examination of the lower extremities of a male cadaver, a significant deviation was observed in the course and pattern of distribution of the left DPA. The artery trifurcated from its point of origin and was found to deviate from its normal course on the superior surface of the intermediate cuneiform, talus, and navicular bones. A lack of the arcuate artery was observed, and a varied branching pattern was established among the branches of the DPA on the dorsum of the foot. Knowing the detailed anatomy of the DPA and understanding its variability is of great clinical importance to surgeons, radiologists, and orthopedists due to the usefulness of this artery in different surgical interventions relating to the foot.

Association of Fusion of the First Metatarsophalangeal Joint and Pes Planus Deformity Correction.

There has been scant investigation on the relationship between the distal aspect of the medial longitudinal arch and pes planus deformity. The aim of this study was to investigate whether the reduction and stabilization of the distal aspect of the medial longitudinal arch through fusion of the first metatarsophalangeal joint (MTPJ) can subsequently improve pes planus deformity parameters. This could be useful in both further understanding the role of the distal medial longitudinal arch in patients with pes planus and planning operative intervention in patients with multifactorial medial longitudinal arch problems. A retrospective cohort study was undertaken between January 2011 and October 2021, including patients undergoing first MTPJ fusion with a pes planus deformity on weightbearing preoperative radiographs. These were compared to postoperative images, and multiple pes planus measurements were taken for comparison. A total of 511 operations were identified for further analysis, with 48 feet meeting the inclusion criteria. There was a statistically significant reduction identified between the pre- and postoperative measurements of Meary angle (3.75 degrees, 95% CI 2.9-6.47 degrees) and talonavicular coverage angle (1.48 degrees, 95% CI 1.09-3.44 degrees). There was a statistically significant increase between the pre- and postoperative measurements of calcaneal pitch angle (2.32 degrees, 95% CI 0.24-4.41 degrees) and medial cuneiform height (1.25 mm, 95% CI 0.6-1.92 mm). Reduced intermetatarsal angle was significantly associated with an increase in first MTPJ angle postfusion. Many of the measurements made were found "almost perfectly" reproducible by the Landis and Koch description. Our results demonstrate that fusion of the first MTPJ is associated with improvement of medial longitudinal arch parameters of a pes planus deformity but not to levels considered to be clinically normal. Therefore, the distal aspect of the medial longitudinal arch could, to some degree, be a feature in the pes planus deformity etiology. Level III, retrospective case control study.

Three-Dimensional Analysis of the Windlass Mechanism Using Weightbearing Computed Tomography in Healthy Volunteers.

The windlass mechanism (WM) increases the longitudinal arch of the foot via tension of the plantar aponeurosis during dorsiflexion of the metatarsophalangeal (MTP) joint. The purpose of this study was to perform a 3-dimensional evaluation of the displacement of each joint and the height of the navicular during dorsiflexion of the first MTP joint by using weightbearing computed tomography (CT). Participants were 6 men and 8 women with 23 healthy feet. CT of the foot with a load equivalent to the participant's body weight was performed. The first MTP joint was in the neutral position and dorsiflexed 30 degrees. Between the conditions, we measured the (1) rotation of each bone, (2) rotation of the distal bone with respect to the proximal bone at each joint, and (3) height of the navicular. With respect to the tibia, the calcaneus was at 0.8 ± 0.7 degrees dorsiflexion and 1.4 ± 0.9 degrees inversion, while the talus was at 2.0 ± 1.2 degrees dorsiflexion and 0.1 ± 0.8 degrees eversion. The navicular was at 1.3 ± 1.2 degrees dorsiflexion and 3.2 ± 2.1 degrees inversion, whereas the medial cuneiform was at 0.3 ± 0.6 degrees plantarflexion and 1.3 ± 1.1 degrees inversion. At the talonavicular joint, the navicular was at 0.7 ± 1.3 degrees plantarflexion, whereas at the cuneonavicular joint, the medial cuneiform bone was at 1.4 ± 1.4 degrees plantarflexion. The height of the navicular increased by 1.1 ± 0.6 mm. We 3-dimensionally confirmed the dynamics of WM and found that the calcaneus, navicular, and medial cuneiform moved in all 3 planes. The results suggest that the cuneonavicular joint has the greatest movement among the joints. We believe that these findings will help to elucidate the pathogenesis of WM-related diseases and lead to advances in treatments for pathologies involving the longitudinal arch. Level IV, case series.

Tenosynovitis of the Anterior Tibialis Tendon: Typical Clinical Radiological Correlation: A Case Report

The Anterior Tibialis Tendon (ATT) is usually the site of minor injuries due to its straight course, however, overuse injuries still possible due to repetitive foot dorsiflexion. This tendon crosses the anteromedial aspect of the ankle running toward the medial border of the foot under the inferior and superior extensor retinacula and inserts at the level of the medial cuneiform and the base of the first metatarsal bone. It can be prone to tendinosis, tenosynovitis, partial or complete tear. In the first cases, the patient experiences a pain and a swelling along the distal part of the ATT worsening while dorsiflexion. The diagnosis may be easily suspected clinically, particularly in significant lesions such a complete tear, but the compensation by the extensor hallucis longus and extensor digitorum longus muscles may delay the diagnosis [1].

Patient with two left cuneiform bones only: A first documented case report

The cuneiforms are three wedge-shaped bones, forming the tarsus of the foot along with the talus, calcaneus, navicular, and cuboid. We present the case of a 70-year-old Caucasian woman with a left unique lateral cuneiform instead of second and third cuneiform bones. Additional cuneiform bones are rare anatomical variants which have been well described in the literature. Conversely, a lesser number of cuneiform bones have never been previously reported. To our knowledge, our article represents the first documented case of this anatomical variation.

Closed Reduction and Percutaneous Fixation of Lisfranc Injury Using Suspensory Fixation.

This closed reduction and percutaneous fixation (CRPF) technique utilizing suspensory fixation is indicated for the treatment of Lisfranc injuries with displacement or instability of the tarsometatarsal joint complex-and typically only for low-energy, purely ligamentous Lisfranc injuries. The goal of this procedure is to restore joint stability and prevent common complications of Lisfranc injuries (e.g., midfoot arch collapse and posttraumatic arthritis) while avoiding the complications and risks associated with open reduction and internal fixation (ORIF) and primary arthrodesis. We recommend performing the procedure within 10 to 14 days of the injury; otherwise, an open debridement may be necessary to address scar tissue formation. We start with the patient in the supine position and perform a fluoroscopic stress examination of the joint. Next, the Lisfranc joint undergoes closed reduction, which is held in place with a clamp. Following reduction, a guidewire is drilled from the lateral border of the base of the 2nd metatarsal medially through the medial cuneiform, followed by a medial-to-lateral cannulated drill. The suspensory fixation is then passed lateral-to-medial, placing the suture button on the lateral cortex of the 2nd metatarsal base. The tape is then tensioned while a bioabsorbable interference screw is inserted to maintain tension. Prior studies have assessed both operative and nonoperative alternatives to CRPF with suspensory fixation for the treatment of Lisfranc injuries. Nonoperative treatment with closed reduction and cast immobilization of Lisfranc injuries is typically reserved for nondisplaced injuries; however, a number of studies have shown poor outcomes with use of this technique1-3. The 2 most common operative alternatives are ORIF and primary arthrodesis4. CRPF with suspensory fixation offers several benefits over both traditional surgical techniques such as ORIF and primary arthrodesis, as well as over percutaneous reduction and internal fixation (PRIF) with a screw. Compared with ORIF and primary arthrodesis, a number of studies have shown that percutaneous treatment of Lisfranc injuries minimizes soft-tissue trauma and reduces the risk of postoperative complications such as wound breakdown, infection, and complex regional pain syndrome, while allowing for earlier participation in rehabilitation5-10. A systematic review of outcomes following PRIF with screw fixation also showed that percutaneous treatment of Lisfranc injuries is a safe and effective technique with good functional outcomes11. When comparing PRIF with a screw to our technique of CRPF with suspensory fixation, CRPF has the added benefit of creating a nonrigid fixation in the Lisfranc joint, which allows for increased range of motion of the medial column and improved return to activity12,13. The rigid fixation in PRIF with a screw can also lead to metal irritation, intra-articular screw fracture, and impaired mobility, which often necessitate the need for screw removal13-15. This fixation-related drawback is not present with our technique, and also avoids the need for use of a biologic substitute such as tendon grafts13. Following CRPF with suspensory fixation, patients can expect to return to full activity at 12 to 16 weeks postoperatively. Postoperatively, patients are typically kept non-weight-bearing for 6 weeks. The operative foot is kept immobilized in a splint for the first 2 weeks, then transitioned to a boot. Between postoperative weeks 6 and 12, partial progressive weight-bearing is introduced with use of an arch support, progressing toward full weight-bearing13,16,17.For comparison, patients who underwent PRIF with screw fixation had a similar postoperative course, but almost all required screw removal at 4 to 6 months postoperatively13,16. Cho et al. retrospectively reviewed the results of 63 patients who underwent either PRIF with screw fixation (n = 32) or CRPF with a suture button (n = 31) and found that CRPF patients had significantly better American Orthopaedic Foot & Ankle Society midfoot scale scores (81 versus 74 points) and visual analog scale scores (3.1 versus 4.6 points) at 6 months postoperatively and prior to screw removal in the PRIF group (p < 0.001). There were no significant differences in these scores, radiographic outcomes, weight-bearing analysis, or complications at 1 year postoperatively. The authors concluded that both techniques provided comparable fixation stability and clinical outcomes. Of note, however, the PRIF group had 4 patients whose postoperative course was complicated by screw breakage13. Start with a fluoroscopic stress examination to identify all components of instability.Ensure that the reduction clamp does not interfere with or affect your guidewire path.If the joint cannot be reduced, convert to an open procedure and debride the obstruction. ORIF = open reduction and internal fixationPRIF = percutaneous reduction and internal fixationCRPF = closed reduction and percutaneous fixationNSAID = nonsteroidal anti-inflammatory drugOR = operating roomAP = anteroposteriorCT = computed tomographyMRI = magnetic resonance imagingAOFAS = American Orthopaedic Foot & Ankle SocietyVAS = visual analog scaleROM = range of motionPT = physical therapyASA = acetyl-salicylic acid (aspirin)BID = twice dailyPRN = as needed.

Double Arthrodesis, Postero-Medial Release and Posterior Tibial Transfer in One Step in Paralytic Inveterate Equine Varus Foot

Introduction: Varus equine foot deformity is common in developing countries. The management of these deformities is surgical in adults. Several surgical techniques have been described with more or less satisfactory results. To our knowledge, no study has been performed on the simultaneous association of double arthrodesis, posteromedial release, and posterior tibial transfer in a single operation in inveterate paralytic varus equines feet. The purpose of this work was to evaluate the results obtained. Patients and Method: This was a retrospective descriptive study from January 01, 2018 to December 31, 2021. It concerned inveterate paralytic varus equines feet operated on by the simultaneous association in a single operative time of double arthrodesis of the foot, posteromedial release of the back foot and transfer of the posterior tibial muscle to the lateral cuneiform. We identified seven patients with a mean age of 22.1 years with extremes of 11 years and 36 years. There were three males and four females. The cause of the deformity was neurological in all cases. All patients had painful walking discomfort and shoeing difficulties. The average time to management was 13.3 years with extremes of 4 and 25 years. The chronology of the interventional steps was posteromedial release, arthrodesis, and transfer of the posterior tibial muscle to the lateral cuneiform. The average postoperative follow-up was 21.7 months with extremes of 6 and 48 months. The parameters studied were the duration of the procedure, complications related to the procedure, muscle strength at the last recoil, consolidation of the arthrodesis, residual pain, patient activity, gait perimeter, stepping, ankle mobility, residual deformity, footwear, protrusion of the transferred tendon, and the possibility of walking on the heel. Final results were graded according to the Angus and Cowell criteria. Results: No intraoperative complications were noted. An early superficial infection of the surgical site was noted. It was treated with local care and healed without sequel. Residual pain was present in one case. Tibiotalar osteoarthritis was observed in one case, which required a tibiotalar arthrodesis. At the last follow-up, consolidation of the arthrodesis was effective in all patients. The posterior tibial muscle was side 5 (n = 4) and 4 (n = 3). The patients’ activity was normal without assistance in all cases. The walking perimeter was greater than 1 km in six patients. Patient activity was normal without assistance in all cases. Stepping was absent in all patients. No difficulty with footwear was noted. According to the Angus and Cowell criteria, the result was good (n = 6), i.e. 85.7% and bad (n = 1), i.e. 14.3% of cases. Conclusion: This study suggests that double arthrodesis associated with posteromedial release and transfer of the posterior tibial in one step in inveterate paralytic varus equines feet, gives satisfactory results. It allows for easy shoeing and plantigrade walking without stepping. Complications are essentially represented by the absence of fusion of the arthrodesis and tibiotalar arthrosis.

Anatomical Study of Sites and Surface Area of the Attachment Region of Tibial Posterior Tendon Attachment.

The purpose of this study was not only to examine the attachment site but also to quantify the effect of the tibialis posterior tendon (TPT) on each attachment site by examining the surface area of the attachment region. We examined 100 feet from 50 Japanese cadavers. The TPT attachment to the navicular bone (NB), medial cuneiform bone (MCB), and lateral cuneiform bone (LCB) were set as the main attachment sites (Type I). The attachment seen in Type I with the addition of one additional site of attachment was defined as Type II. Furthermore, surface area was measured using a three-dimensional scanner. Attachment to the NB, MCB, and LCB was present in all specimens. The TPT attachment to the NB, MCB, and LCB comprised 75.1% of total attachment surface area. The ratio of the NB, MCB, and LCB in each type was about 90% in Types II and III, and 70-80% in Types IV-VII. The quantitative results demonstrated the NB, MCB, and LCB to be the main sites of TPT attachment, although individual differences in attachment sites exist, further developing the findings of previous studies.

Does ankle arthrodesis induce satisfactory changes in the medial longitudinal arch height of the foot for severe varus ankle arthritis?

We designed this study to determine how changes in coronal ankle alignment affect sagittal alignment of the foot. Specifically, we focused on the changes in medial longitudinal arch height, which could be reflected by the medial cuneiform height (MCH), Meary's angle, and calcaneal pitch angle (CPA). We retrospectively analyzed the radiographic findings of 37 patients who underwent open ankle arthrodesis without inframalleolar correction (such as first metatarsal dorsal closing wedge osteotomy, calcaneal osteotomies, tendon transfers, or tarsal joint arthrodesis) of severe varus ankle arthritis. The inclusion criterion was a pre-operative tibial axis to talar dome angle of 80 degrees or less. The enrolled patients were divided into two groups according to the post-operative decrease in MCH (≥ 2mm or < 2mm). A post-operative MCH decrease of ≥ 2mm was observed in 43.2% (16 patients). Although the degree of coronal ankle varus correction was similar, the decrease in the Meary's angle was significantly greater in the group with a post-operative MCH decrease of ≥ 2mm than in those with < 2mm (- 4.1 degrees vs. - 1.3 degrees, P = 0.01). The changes in CPA were not significantly different (P = 0.172). Correction of ankle varus deformity via ankle arthrodesis could lead to a decrease in the medial longitudinal arch height in less than half of the enrolled patients. In these patients, a cavus component of the foot might be an important factor in determining a successful sagittal foot alignment change, while the CPA was maintained post-operatively.

Interference Screw vs Suture Button Fixation for Tibialis Anterior Tendon Transfer to Lateral Cuneiform: A Biomechanical Analysis with Implications for Clubfoot Treatment

Category: Other Introduction/Purpose: While transfer of the tibialis anterior tendon (TAT) to the lateral cuneiform (LC) following serial casting has been used for over 60 years to treat relapsed clubfoot deformity, modern methods of tendon fixation remain largely unstudied. Though interference screw fixation has the potential of obviate concerns of pressure necrosis and proper tendon tensioning associated with plantar button suspensory stabilization, a better understanding of LC morphology in young children is a necessary first step in assessing the viability of this fixation technique. The purpose of this investigation is therefore to define LC morphology in children aged 3-6 years. Methods: A retrospective radiographic review of 40 healthy pediatric feet aged 3-6 years who had either MRI or CT scans was performed at a single pediatric hospital. The length, width, and height of only the ossified portion of the LC were measured digitally using sagittal, coronal, and axial imaging. In addition, the maximal cross-sectional diameter of the TAT was measured at the level of the tibiotalar joint. Results: Average ossified LC width ranged from 8.5mm in the 3-year-old cohort to 10.3mm in 6-year-old children. While the average width increased with each year of age, ANOVA testing revealed no statistically significant difference in width between age groups (p=0.091). Average ossified LC length ranged from 13.5mm in the 3-year-old cohort to 18.3mm in 6-year-old children with statistically significant increases in all age groups separated by two or more years (p=0.017). the TAT to ossified LC width ratio ranged from 44% to 53% across age groups. (table 1). Conclusion: The dimensions of the LC ossification center are large enough to allow interference screw fixation in children 3 to 6 years of age.

3-Dimensional Analysis of First Tarsometatarsal Joint after First Metatarsal Osteotomy with Weightbearing CT (WBCT)

Category: Midfoot/Forefoot; Bunion Introduction/Purpose: The pathology of the bunion deformity consists of deformities in the axial, coronal, and sagittal planes of the first metatarsal and its articular surface with the medial cuneiform. While weightbearing radiographs have been utilized for assessment of these deformities, such methods have limitations with regard to image magnification, patient position, and superimposition of bone alignments. With advances with weightbearing computed tomography (WBCT), evaluation of the 3- dimensional components of the first metatarsal along with its proximal articular surface can be assessed with greater precision. This study aims to observe the effect of the midshaft osteotomy on the alignment of the tarsometatarsal joint in three dimension Methods: Ten feet in 10 subjects underwent midshaft first metatarsal osteotomies. Weight-bearing (using a load equivalent to body weight) CT scans with .3mm cubic voxel size using an original loading device preoperatively and postoperatively were collected from each of the subjects in neutral standing position. Scans were segmented, and 3D renderings of the medial cuneiform, first metatarsal, and the first phalanx were also generated from the segmentations followed by definition of reference frames to evaluate changes in the metatarsal in relationship to the medial cuneiform. (Fig.1) Results: The measurements of the rotational parameters showed greater changes in the sagittal plane postoperatively with dorsiflexion of the first metatarsal relative to the medial cuneiform at the first tarsometatarsal joint (p&lt;0.05).(Fig.2) Post-operative changes in the coronal plane and axial plane with relationship of the first metatarsal to the medial cuneiform were noted. Distance mapping showed a significant increase in surface-to-surface distance at the dorsal tarsometatarsal joint post-operatively with a reduced distance at the inferior portion of the tarsometatarsal joint. (Fig.3). Conclusion: Based on the results of the study, midshaft osteotomies of first metatarsal can cause increased dorsiflexion in the sagittal plane, significant eversion in the coronal plane, and external rotation in the axial plane at the tarsometatarsal joint. Distance mapping analysis on WBCT images identified differences in surface-to-surface interaction of the first metatarsal and the medial cuneiform

Interobserver Reliability of Radiographic Angles and Measurements in Flat Foot Deformity

Category: Other Introduction/Purpose: Radiographic angles and measurements are widely used in foot and ankle pathologies to define normal and abnormal skeletal alignment. In spite of this the inter-observer reliability of these parameters is debatable. The aim of this study was to determine the inter-observer reliability of various radiographic angles and measurements in flat foot deformity. Methods: Antero-posterior (AP) and lateral foot radiographs of 18 patients with flatfoot deformity were analysed by eight clinicians of various grade of experience (2 consultants, 4 fellows / registrars and 2 core training grades) with 11 different radiological parameters. A digital presentation demonstrating the method of measurement of all parameters using same software was provided to the participants. The inter-observer reliability was analysed using interclass correlation (ICC) model mixed for reliability at 95% confidence interval for individual parameters and different grade of experience. Results: The inter-observer reliability was excellent (&gt;0.9) in calcaneal pitch angle (CPA), medial cuneiform height (C1H) and lateral incongruency angle (LIA). It was good (0.75 - 0.90) in talo-navicular angle (TNA), medial cuneiform articular angle (CAA), medial arch sag angle (MASA), medial cuneiform - 1st MT angle (C1MTA), talonavicular coverage angle (TNCA)andtalar - 1st MT angle on AP radiograph (T1MTA). The inter-observer reliability was moderate (0.5 - 0.75) in Meary's angle and talo-navicular uncoverage percentage (TNUP). The reliability did not differ with the grade of surgeon on sub-group analysis. Conclusion: This is first study to analyse the interobserver reliability of radiographic measurements in a flatfoot deformity, including grade of surgeon. The results suggest that these radiological parameters can be reliably used in clinical practice if standard measurement techniques are followed by clinicians of all grades.

Factors Influencing Postoperative Residual Diastasis after the Operative Treatment of Acute Lisfranc Fracture-Dislocation

Category: Trauma; Midfoot/Forefoot Introduction/Purpose: 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). 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&gt;0.05 each). Preoperative foot 3D-CT evaluation showed that the rate of large (&gt;25% of 2nd tarsometatarsal joint involvement), displaced (&gt;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). Conclusion: 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.

Augmented Stress Weightbearing CT for Evaluation of Subtle Lisfranc Injuries in the Elite Athlete

Category: Midfoot/Forefoot; Trauma Introduction/Purpose: The Lisfranc joint is the interface between the midfoot and forefoot and forms a strong connection due to its bony architecture and ligamentous attachments in the foot. An unstable Lisfranc injury has traditionally been defined as displacement &gt;2 mm between the 1st and 2nd metatarsal bases or between the medial cuneiform and the second metatarsal base, when compared to the contralateral side on imaging modalities. Classically, Lisfranc injuries have been detected with standard X- ray, stress plain films, standard CT, MRI and ultrasound. We describe an imaging technique that may be used to further assist in the diagnosis and management of subtle Lisfranc injuries, and include a case to demonstrate its use in athletes. Methods: Cone beam weight bearing computed tomography (WBCT) is a well-described imaging modality for evaluation of foot and ankle injuries. We have found it highly beneficial to teach our CT technologists about Lisfranc injuries and the importance of augmented physiologic stress applied across the midfoot (in addition to the standard WBCT) to better demonstrate instability or motion, particularly at the second TMT joint. To perform an augmented stress weight bearing CT, the patient is positioned in the WBCT scanner and initial images are acquired in the standing weight bearing position with feet directed forward and weight distributed equally. A second image acquisition is then performed (augmented stress), where the patient is coached to lift both heels from the scanner platform symmetrically, in a calf-raise type exercise. It is important that the patient distributes weight as evenly as possible between the feet so the affected side is stressed sufficiently. Results: We present here a 22-year-old male collegiate football player who is an offensive lineman. While blocking during a game, his foot was plantarflexed, and he 'felt a pop' in his midfoot. On exam, the player was tender to palpation over the medial midfoot, at the Lisfranc joint. He had pain with forced pronation and abduction as well as axial load through the first webspace. Initial weight bearing radiographs did not show evidence of widening between the medial cuneiform and second metatarsal base. Due to his concerning examination, an MRI was ordered, which revealed a small bony avulsion off the plantar aspect of the second metatarsal base with an otherwise intact Lisfranc ligament. He then underwent weightbearing CT stress views of the foot, which revealed greater than 2 mm of widening between the first and second metatarsals when compared to the contralateral side, indicating instability of the Lisfranc joint. Conclusion: We present the augmented stress weightbearing CT technique of the midfoot to evaluate for subtle Lisfranc injury. The need for this imaging modality has proven useful in the elite athlete with subtle injury to the midfoot, otherwise not found on conventional imaging techniques. Timely diagnosis and treatment is imperiative to these players due to the morbidity associated with missed Lisfranc injuries. We propose this technique for diagnosing otherwise unrecognized, subtle Lisfranc injuries in patients where clinical suspicion persists despite negative imaging because this technique stresses the joint and we believe makes the weightbearing CT more sensitive for this injury.

Coronal Plane Rotation of the Medial Column in Hallux Valgus (HV), Progressive Collapsing Foot Deformity (PCFD), and Combined PCFD HV: A Retrospective Case Control Study

Category: Bunion; Hindfoot; Midfoot/Forefoot Introduction/Purpose: The presence of hyperpronation of the first metatarsal (M1) seems to have a clinically significant role in Hallux Valgus (HV). Some authors reported a decrease in recurrence rates after M1 hyperpronation correction in HV. However, when measuring the M1 head pronation relative to the ground, we are assessing and quantifying the aggregate coronal rotational profile of each bone and joint throughout the medial column. Therefore, we do not know the location of this hyperpronation. Moreover, studies showed a strong influence of the hindfoot alignment on coronal rotational measurements and Progressive Collapsing Foot Deformity (PCFD) is a condition frequently associated with HV. Our study aimed to assess and compare coronal plane alignment of medial column bones in HV, PCFD, PCFD HV and controls. Methods: We performed a retrospective IRB approved study. We collected 33 feet who consulted our center with combinations of symptomatic PCFD and HV. We then matched 33 HV, 33 PCFD, and 33 controls for BMI, Gender, and Age to this group. We assessed the coronal plane rotation of the navicular, medial cuneiform, M1 at its base and head, the Sesamoid Rotation Angle (SRA) with respect to the ground, and the hallux valgus angle (HVA) using Weight-Bearing CT images (Figure).The positions of the different joints (first naviculocuneiform (NC1), first tarsometatarsal (TMT1) and metatarsosesamoid rotation angle (MSRA)) were found by subtracting the adjacent angles. Intrinsic torsion of M1 was calculated by subtracting the M1 base angle from the M1 head angle.Normality of different variables was assessed using the Shapiro-Wilk test. Groups were compared using t test or ANOVA for normal and Mann Whitney or Kruskal Wallis for nonnormal variables. Results: HV, PCFD and PCFD HV presented higher M1 intrinsic torsion when compared to controls (respectively 7.3°[CI95%:2.9-11.7], p&lt;0.001; 7.5°[CI95%:2.5-12.6], p&lt;0.001; 7.5°[CI95%: 2.9-12],p&lt;0.001).The navicular was more pronated in PCFD HV compared to controls (respectively 20+/-5.2° vs 12.5+/-3.9°,p&lt;0.001) whereas it was not for PCFD and HV.NC1 was 6.8° significantly more supinated in HV (p&lt;0.001) and 5.7° in PCFD HV (p&lt;0.001) compared to controls whereas there was no significant difference between PCFD HV and Controls.TMT1 was 7.3° significantly more pronated in HV (p&lt;0.001) and 4.9° in PCFD HV (p&lt;0.001) compared to controls whereas there was no significant difference between PCFD HV and Controls. MSRA was significantly higher in HV (p&lt;0.001) and PCFD HV (p&lt;0.001) compared to controls whereas there was no significant difference between PCFD and Controls. In multivariate analysis, MSRA (β=0.95,[0.83;1.07], p &lt;0.0001) were associated with higher values of HVA whereas NC1 (β=-0.24,[-0.42;-0.06], p= 0.0076) were associated with lower values of HVA. Conclusion: The intrinsic increase in M1 pronation appears to be a shared developmental abnormality in PCFD and HV. Combination of PCFD and HV seems to originate from the presence of a paradoxical supinatory malposition of the NC1 which was not present in PCFD without HV in our study. The presence of this compensatory supination malposition might explain the presence of HV by causing a metatarsosesamoid dislocation in HV and PCFD HV. In contrast, hyperpronation compensation in PCFD without HV might be proximal to the navicular because there was no difference between PCFD and control regarding the navicular position in our study.

Progressive Collapsing Foot Deformity Correction using Longitudinal Arch Support Inflatable Ankle- Foot Orthosis: A Prospective Case-Control Study

Category: Midfoot/Forefoot; Ankle; Hindfoot Introduction/Purpose: Progressive Collapsing Foot Deformity (PCFD) comprises five independent deformities represented by five classes: hindfoot valgus (class A), midfoot abduction (class B), forefoot varus (class C), peritalar subluxation (class D) and ankle valgus (class E). Conservative treatment includes the use of corrective insoles and orthotics. Longitudinal arch support inflatable ankle-foot orthoses (IAFO) help control pain in PCFD patients. But we have no knowledge about the ability of IAFOs to correct deformities in PCFD. The aim of this prospective case-controlled study was to assess the ability of longitudinal arch support IAFOs to correct 3D overall PCFD alignment as well as the five different PCFD classes independently. We hypothesized that IAFOs will correct PCFD 3D overall alignment as well as the five independent classes. Methods: After IRB approval we enrolled 24 symptomatic flexible PCFD and 24 controls matched on age, sex, and BMI. Patients were scanned using Weight-Bearing CT with and without a longitudinal arch support IAFO. The Foot and Ankle Offset (FAO) was used to assess the 3D foot overall alignment. We measured the Hindfoot moment arm (HMA, Class A), the Talonavicular coverage angle (TNCA, Class B), the Meary's angle and the distance between the floor and the medial cuneiform (C1-floor) for the Class C and the middle facet uncoverage (MFunco, Class D). We did not have any Class E deformity in our PCFD cohort. Data normality was assessed by Shapiro-Wilk test. Comparisons used normality based paired T-tests or paired-Wilcoxon tests. Hypothesizing that the IAFOs would be two times less efficient than the surgery (Day et al.) in correcting the FAO in PCFD, the requisite number of subjects was 24 per group. Results: Control measurements were all significantly different than unbraced PCFD measurements confirming our PCFD selection process. Comparing PCFD without and with IAFO via FAO did not show significant improvement (respectively 6.6+/- 3.7% vs 5.5+/-4.2%, p=0.101). The HMA (8.8+/-5.8 vs 8.1+/-5.8, p=0.66), the TNCA (24.2+/-10.6 vs 21.9+/-9.7, p=0.44) and the MFunco (37+/-12% vs 31+/-18%, p=0.17) did not show any significant improvement when applying the IAFOs. The Meary's angle (17.6+/-7.2 vs 10.8+/-7.3, p=0.002) and the C1-floor (17.2+/-3.3mm vs 24.1+/-5.3mm, p&lt;0.001) were significantly improved by the IAFOs. The only measurements which was normalized when compare the PCFD to the control group after applying the IAFO was the C1-floor (24.1+/-5.3mm in PCFD with IAFO vs 25.7+/-5.4mm in controls, p=0.31) Conclusion: In this prospective case-control study, we found that longitudinal arch support IAFOs were less than half as effective as surgery in correcting overall 3D deformity in PCFD. Likewise, IAFOs were not efficient in correcting hindfoot valgus (Class A), midfoot abduction (Class B) and peritalar subluxation (Class D) in PCFD. On the other, IAFOs were effective in correcting forefoot varus and medial longitudinal arch collapse (Class C). This study provides relevant information to guide medical treatment and longitudinal arch support IAFO prescription in PCFD.

Reliability of Weight-Bearing Ultrasonography for Diagnosis of Lisfranc Joint Injuries: A Cadaveric Study

Category: Trauma Introduction/Purpose: Ultrasonography is increasingly used to evaluate the stability of various joint in the field of foot and ankle. This study aims to assess and compare the Lisfranc joint stability under stimulated weight bearing condition among progressive stages of Lisfranc ligamentous complex injuries. All the measurements were assessed using ultrasonography, fluoroscopy, and direct open measurement. We hypothesize that there is a correlation between ultrasonographic and fluoroscopic measurements, or between ultrasonographic and direct open measurements when performing stress evaluation of the Lisfranc instability. Methods: Twelve fresh below-knee amputated cadaveric specimens underwent ultrasound, fluoroscopic, and direct gross evaluation of the Lisfranc stability under simulated weight bearing condition. The assessment was first performed with all Lisfranc ligamentous complex intact and thereafter with sequential transection of the dorsal Lisfranc ligament, interosseous Lisfranc ligament, and plantar Lisfranc ligament. The simulated weight bearing condition was performed with 600N of force. The distances evaluated during the experimental set up were C1-M1, C2-M2, C1-M2, C1-C2 and M1-M2. All measurements were recorded in millimeter (mm). The ultrasound machine (GE, LOGIQ E-9 ultrasound machine, Chicago, Illinois, USA) was used to assess the Lisfranc stability by measuring the distances between the hyperechoic bone contours or the pre-defined landmark of the metatarsal and cuneiform bones. Correlations between 1) Ultrasound and fluoroscopic measurements, 2) Ultrasound and direct open measurements, and 3) Fluoroscopic and direct open measurements were evaluated using Pearson correlations coefficient. Results: Strong positive correlations between ultrasonographic and direct open measurements were found when assessed for C1-M1, C1-M2, C1-C2, M1-M2 (Pearson's correlation ranged from 0.73-0.97, p-values &lt;0.001). Strong positive correlations between ultrasonographic and fluoroscopic measurements were found when assessed for C1-M1 from dorsal, medial, and plantar aspect (Pearson's correlation ranged from 0.75-0.90, p-values &lt;0.001). Strong positive correlations between fluoroscopic and direct open measurements were found when assessed for C1-M1, C1-M2, C2-M2, M1-M2 (Pearson's correlation ranged from 0.77-0.93, p-values &lt;0.001). Inter-rater and intra-rater reliability for the ultrasonographic measurements between the MSK radiologist (TK) and the foot and ankle surgeon (JS) were substantial (ICC ranged from 0.81-0.98). Conclusion: Ultrasonography is a reliable and reproducible tool for diagnosing Lisfranc ligamentous complex injuries. Both ultrasonographic and fluoroscopic measurements appear to strongly correlate with values measured by direct open measurement. Based on these data, ultrasonography is likely to become a valuable point of care diagnostic tool due to its ability to readily and dynamically evaluate suspected Lisfranc ligamentous complex injuries, without radiation exposure.

Nitinol Shape Memory Staple Fixation of Lisfranc Fractures is Safe and Efficacious

Category: Trauma; Midfoot/Forefoot; Sports Introduction/Purpose: Surgical treatment of Lisfranc fractures has evolved from arthrodesis or transarticular screw fixation to joint preserving modalities (suture buttons and/or dorsal spanning plates), the latter commonly requiring removal due to metalwork irritation and to restore motion at the 1st-MTPJ. Shape memory staples formed from Nitinol exploit its biomechanical properties of; low Young's modulus, super elasticity and high ductility. To produce a robust implant that generates greater compressive forces at its distal end compared to traditional 316L stainless steel compression staples. Permitting the construction of a rigid fixation for Lisfranc fractures that is achieved with transarticular screws or plate fixation, but is mobile and elastic as with suture buttons. This study aims to assess the surgical outcomes of staple fixation in acute Lisfranc fractures. Methods: A prospective study to assess for union and necessity for revision surgery was completed for consecutive Lisfranc fractures treated with Nitinol shape memory staple fixation from June 2020 at a single U.K. Level 1 Major-Trauma-Centre. All operations were performed or supervised by a single fellowship trained Major Trauma Foot &amp; Ankle Surgeon through a EHL bed approach to access the base of the 2nd MT and cuneiforms. Relevant joints were debrided and reduced, held with K-wires and reduction clamps to allow for the placement of the staples. A triangular configuration for the placement of three staples (2nd MT to Middle Cuneiform, 2nd MT to Medial Cuneiform, Middle to Medial Cuneiform). Reduction of the Lisfranc complex was confirmed on intra-operative fluoroscopy. Patients were non-weight bearing for 4 weeks with appropriate VTE prophylaxis. Staples were placed so as to not penetrate the plantar cortex and inter-cuneiform instability was assessed and confirmed intra- operatively. Results: Results from 19 consecutive patients were analysed, consisting of 9 men 10 women, with a mean age of 44 years (19-76). Seven patients sustained high energy trauma. Mean time to theatre was 18 days (5-28) from date of injury. Mean total operative time was 70 minutes, (27-154) with an mean tourniquet time of 63 minutes. An mean length of follow-up was 13.5-months (range 6-20 months), with a 100% union rate on weight-bearing radiographs and no incidences of post-operative complications requiring further medical or surgical intervention. No patients reported symptomatic implant irritation which required consideration of metalwork removal. The average FADI score was 73/104 (70%) at longest follow-up. Conclusion: Nitinol shape memory staple fixation of Lisfranc fractures is safe and efficacious, removing the necessity for metalwork removal as is commonly seen with dorsal bridging plates whilst maintaining the structural rigidity of plate/trans-articular screw fixation at the same time as allowing for physiological motion at the 1st-MTPJ. Patient reported outcome measures of this technique demonstrate equitable outcomes to more conventionally used techniques. This is the largest series of shape memory alloy staple fixation of acute Lisfranc injuries the authors are aware of and demonstrates that this technique should be considered a part of a surgeons' armamentarium when treated Lisfranc injuries.

Does a 1st Metatarsophalangeal Fusion in a Patient with Pes Planus Improve the Pes Planus Deformity? A Retrospective Case Series

Category: Midfoot/Forefoot; Bunion Introduction/Purpose: A pes planus deformity is a pathology relating to the loss of normality of the complex interaction of the bones and joints of the foot resulting in a flattening of the medial longitudinal arch with or without abduction of the midfoot. The distal aspect of the medial longitudinal arch can be a feature of the deformity. The fusion of the 1st metatarsophalangeal joint (MTPJ) is a common operation. In patients with concomitant pes planus deformity, it is unknown if reducing and stabilising the distal aspect of the medial ray through a 1st MTPJ fusion can subsequently improve the pes planus deformity. We sought to analyse the pes planus deformity pre and post 1st MTPJ fusion with the null hypothesis that there was no difference. Methods: We identified patients who had undergone 1st MTPJ fusion using our electronic database from January 2011 to October 2021. To meet the inclusion criteria, cases required pre- and post-operative weightbearing plain radiographs, with a Meary's angle of &gt;4 degrees on pre-operative imaging. Routine pes planus measurements were undertaken by 2 independent observers. Pre- and post-operative measurements were tested for significant change using Wilcoxon Signed Rank Test or Paired T-Test depending on the normality testing of the data. Routine demographic data was also collected. Data was analysed using IBM SPSS v.27. Results: Following radiographic analysis, 25 feet fitted the inclusion criteria. The mean patient age was 63 years. There was no pre-operative correlation between Meary's angle and the hallux valgus angle (Kendall's tau p=.441). Pre-operatively, Meary's line broke at the talo-navicular and navicular-cuneiform joints in 12 cases each; the remaining case broke at the tarsal-metatarsal joint. A statistically significant improvement between the pre- and post-operative measurements was identified in Meary's angle, calcaneal pitch angle, talo-navicular coverage angle, intermetatarsal angle and talo-navicular angle (see table). Significant changes were also noted in the medial cuneiform height (mean increase of 2.74mm; p=.022). A post-operative Meary's angle of &lt;4°was only achieved in 4/25 (16%) of cases. Of the remaining 21 cases, the point at which Meary's line broke moved proximally one joint in 4 and distally one joint in 3 cases; it remained at the same joint in 14 cases. Conclusion: Our results suggest that 1st MTPJ fusion improves axial alignment of the foot as well as reducing Meary's angle by a statistically significant amount, although diagnostic criteria for pes planus remained in most cases.

Retrospective chart review: Weightbearing CT scans and the measurement of the Lisfranc ligamentous complex

BackgroundLisfranc Ligamentous Complex (LLC) injuries are commonly misdiagnosed due to their unreliable projection on plain films. Weightbearing CT (WBCT) scans are a relatively new imaging modality that has not yet been utilized to establish widely referenced baseline anatomic positions. MethodsA retrospective chart review was conducted of patients who had undergone weightbearing CT of the bilateral lower extremities with one-hundred and twelve being included (56 patients). Measurements of the Lisfranc joint were collected by two independent reviewers. Uninjured symmetric anatomy was used to describe a baseline for normal anatomic variation and to evaluate for sex-based or age-related differences. These measurements were then compared against the injured side. ResultsIn patients without Lisfranc injury, the 1st metatarsal base to 2nd metatarsal base distance (Base M1-M2) was 2.7 + /− 0.7 mm; 2nd metatarsal base to medial cuneiform (M2-C1) was 3.7 + /− 0.7 mm; intercuneiform distance was 1.2 + /− 0.3 mm; and sagittal descent 12.2 + /− 5.4 mm. Patients with injury to LLC had a larger M1-M2 base distance (Δ = 0.5903, p < 0.0001) and M2-C1 interval (Δ = 1.8008, p < 0.0001) compared to uninjured side. Males had significantly higher M2-C1 (p = 0.0031), intercuneiform distance (p = 0.0039), and sagittal descent (p = 0.0008) compared to female patients. No significant differences were found between left versus right side in any of the measurements. Intercuneiform distance (p = 0.0039) was found to significantly decrease as age increased, while sagittal descent significantly increased with increased age (p = 0.0066). ConclusionWeightbearing CT has high utility in identification of Lisfranc injuries particularly when comparing injured and uninjured sides, which may be its greatest utility in defining injuries. This is evident in the excellent diagnostic ability of the M2-C1 measurement. By defining baseline anatomic measurements for Lisfranc complex parameters in our patient population, we provide normal parameters for comparison when evaluating potential subtle injuries. Level of evidenceIII