Midfoot Instability Research Articles

Weightbearing Imaging Assessment of Midfoot Instability in Patients with Confirmed Hallux Valgus Deformity: A Systematic Review of the Literature.

Hallux valgus deformity (HVD) involves subluxation of the first metatarsophalangeal joint. While HVD is primarily considered a forefoot condition, midfoot instability may play a significant role in its development and severity. However, very few studies have placed a heavy emphasis on studying this phenomenon. Therefore, this review had a particular focus on understanding midfoot instability based on weightbearing imaging assessments of the TMT joint. This review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and searched five databases for studies on midfoot instability in HVD patients. The severity of HVD was defined by hallux valgus angle (HVA) and distal metatarsal articular angle (DMAA). Data was extracted, and articles were graded using the Methodological Index for Non-Randomized Studies (MINORS). Of 547 initially retrieved articles, 23 met the inclusion criteria. Patients with HVD showed higher HVA and DMAA on weightbearing radiographs (WBRG) and weightbearing computed tomography (WBCT) compared to healthy individuals. Midfoot instability was assessed through intermetatarsal angle (IMA) and tarsometatarsal angle (TMT angle). Patients with HVD exhibited greater IMA and TMT angles on both WBRG and WBCT. This review highlights the importance of weightbearing imaging assessments for midfoot instability in HVD. IMA and TMT angles can differentiate between healthy individuals and HVD patients, emphasizing the significance of midfoot assessment in understanding HVD pathology. These findings validate the limited evidence thus far in the literature pertaining to consistent midfoot instability in HVD patients and are able to provide ample reasoning for physicians to place a larger emphasis on midfoot imaging when assessing HVD in its entirety.

Lisfranc Injury: Recent Trends in Management.

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

Evaluation of the heel external rotation test in soft tissue deficiencies associated with adult acquired flatfoot deformity (AAFD). A cadaver sectioning analysis.

To date, evaluation of the heel external rotation test has not been taken with respect to AAFD. Traditional 'gold standard' tests do not account for the contribution of the midfoot ligaments towards instability. These tests would be flawed as any midfoot instability may produce a false positive result. To evaluate the differential contribution of the spring, deltoid and other local ligaments in external rotation generated at the heel. Serial ligament sectioning was performed on 16 cadaveric specimens, with a 40N-external rotation force applied to the heel. These were divided into four groups with different sequences of ligament sectioning. Measurements of the total amount/range of external, tibiotalar and subtalar rotation were made. The deep component of the deltoid ligament (DD) was the main ligament influencing heel external rotation (P<0.05, in all cases), and acted primarily at the tibiotalar joint (87.9 %). The spring ligament (SL) influenced heel external rotation predominantly (91.2 %) at the subtalar joint (STJ). Greater than 20 degrees external rotation could only be achieved with DD sectioning. The interosseous (IO) and cervical (CL) ligaments did not significantly contribute to external rotation at either joint (P>0.05). Clinically relevant external rotation (>20 degrees) is solely attributable to DD failure in the presence of intact lateral ligaments (LL). This test may improve detection of DD instability and allow clinicians to subclassify patients with Stage 2 AAFD into those where DD may or may not be compromised.

Importance of Midfoot Ligaments in a Hallux Valgus Cadaveric Model

Category:BunionIntroduction/Purpose:Hallux valgus (HV) is of uncertain origin. Even though a huge amount of treatment options are available, no clear cause for this deformity exist. To be able to further understand this frequent pathology, a cadaveric model should be developed. A cadaveric model was developed trying to obtain similar deformities to the ones observed in Hallux valgus (first ray varus and pronation). The objective of this research is to recreate some characteristics of a HV deformity, through sequential ligaments sectioning.Methods:8 fresh frozen lower leg specimens were used. Markers were attached to the medial and middle foot ray bones, including talus. A constant tibial axial load of 25 kg was used. Cyclic tibial rotation (to simulate gait phases) and 5 kg pull on the extensor and flexor hallucis tendons (EHL and FHL) were applied to the specimen. Limited and sequential medial and middle column ligamentous sectioning were performed, including the, dorsal and interosseous naviculo-cuneiform, intercuneiform, metatarso-cuneiform and intermetatarsal ligaments. After each ligament damage, bony alignment was measured including frontal (bone divergence) and axial plane (bone rotation).Results:After intercuneiform, Lisfranc and naviculo-cuneiform ligaments sectioning, a significant angular increase was found in the naviculo-cuneiform, intercuneiform and naviculo-metatarsal angles (p=0.001). Specifically, for bone rotation, the biggest change was found for the intercuneiform and naviculo-cuneiform angles. Regarding bone divergence, the biggest increase was found in the talo-metatarsal angle. No additional angular change was found after adding metatarso-cuneiform ligament damage. No change in the sagittal alignment was found.Conclusion:This model was able to recreate some parameters of the hallux valgus deformity. No flatfoot deformity was produced. Surprisingly, no significant angular change was produced after metatarso-cuneiform ligament damage. Most significant changes were found after intercuneiform and naviculocuneiform damage. Our findings suggest that midfoot instability has to be present to recreate a hallux valgus deformity.

Joint-preserving surgical correction of advanced flexible planovalgus deformity of the adult foot

Adult acquired flatfoot deformity is characterized by aprogressive functional deficit of the foot that leads to an eversion of the subtalar joint complex with heel valgus, abduction of the forefoot and collapse of the medial arch. In the case of aflexible deformity, ajoint-preserving operative reconstruction is advisable, which should correct all elements of the deformity. Acalcaneal lengthening osteotomy can correct excessive abduction of the forefoot, which can be measured by the amount of talar head uncoverage visible on AP weight-bearing x‑rays of the foot. Any calcaneal lengthening osteotomy leads to an incongruence between talar and calcaneal joint surfaces of the subtalar joint, which is arisk factor for secondary degenerative changes. It is, therefore, advisable to limit the amount of lengthening to thenecessary minimum. Aresidual heel valgus can be corrected by an additional medial displacement osteotomy as adjunct to the calcaneal lengthening. Calcaneal osteotomies are usually part of acomplex reconstruction of advanced but still flexible adult flatfoot deformities. In addition to the correction of the hindfoot deformity, persistent forefoot supination needs to be corrected. In cases of midfoot instability, which is frequently located in the naviculo-cuneiforme joint line, acorrective arthrodesis is recommended. Without midfoot instability forefoot aCotton osteotomy is able to reduce forefoot supination and add to reconstruction of the medial arch of the foot. All bony corrections should be combined with soft tissue reconstruction, i.e. spring ligament repair, Flexor tendon transfer and, in cases of gastrocnemius shortening, agastroc recession.

Biomechanical Analysis of Midfoot Instability After Bifurcate Ligament Injury and Ankle Brace Application: A Cadaveric Study

This cadaveric study investigated the biomechanical characteristics and stabilizing contribution of the bifurcate ligament using a multidirectional loading method and assessed the stabilizing effect of a brace after injury of the ligament. Eight freshly frozen cadaveric feet were tested for forefoot torque in inversion, eversion, adduction, and plantarflexion. Each band of the bifurcate ligament was transected sequentially, and the contribution of each portion of the ligament, as well as the stabilizing effects of the ankle brace, were examined. Stability decreased substantially after calcaneocuboid ligament transection for inversion and adduction loading. Bracing restored some stability, except for the adduction loading direction, for which it had only limited effect. The data indicate that inversion and adduction loading are strongly related to bifurcate ligament injury. The stabilizing effect of the ankle brace may have limited effectiveness for loads under adduction.

Appropriate MRI Evaluation of Lisfranc Ligaments: How to Avoid Missing Ligamentous Lisfranc Injuries

Knowledge of injuries at the tarsal metatarsal joints continues to evolve. Fractures and ligamentous injuries at the tarsal metatarsal joints, also known as the Lisfranc joint complex, are uncommon yet can be of great clinical significance. The initial radiographic findings, suspected mechanism of injury, and physical examination findings can result in varying diagnoses and recommendations. Subtle or ligamentous injuries can be missed and result in the potential of midfoot instability and rapid progression to posttraumatic osteoarthritis. The imaging features of injury at the Lisfranc joint are reviewed, and guidance is provided as to the appropriate use and interpretation of weight bearing radiographs, computed tomography, and magnetic resonance imaging. This will include a description on the utilization of magnetic resonance imaging in evaluating ligamentous Lisfranc injuries to aid clinicians in successfully diagnosing a ligamentous or subtle injury.

Does Total Ankle Arthroplasty Preserve Midfoot Function and Mitigate Excessive Adjacent Joint Loading?

Category: Ankle Arthritis Introduction/Purpose: The progressive decline of ankle motion secondary to ankle arthritis increases midfoot joint loading during forward propulsive activities. Preservation or improvement of ankle motion following total ankle arthroplasty (TAA) is theorized to preserve adjacent joint function and potentially mitigate the cumulative effect of midfoot joint loading. If this theory were sound, the biomechanical profile of midfoot function would not change following TAA. Examination of this theory may inform TAA operative care and will directly impact postoperative rehabilitation paradigms. The purpose of this ongoing study was to be the first to prospectively evaluate the effect of TAA on midfoot function during walking, as measured by midfoot range of motion and power, at six month follow up. Methods: Nine adults [Mean (SD): Age 60.2 (3.5) years; BMI 30.4 (1.4) Kg/m2; 100% male] who received a TAA for end-stage ankle arthritis walked barefoot on level ground preoperatively and six months postoperatively. Three dimensional motion analysis was used to record three-segment foot motion (forefoot, rearfoot, tibia) and ground reaction forces. Midfoot (forefoot with respect to rearfoot) sagittal and transverse plane range of motion were measured. Inverse dynamic calculations were used to obtain midfoot negative (absorption) and positive (generation) peak power (joint torque x segmental velocity), since these metrics are biomechanical correlates of midfoot instability and stability, respectively. Accordingly, greater midfoot joint loading would be characterized by increased power absorption. Greater power generation would indicate an increased midfoot contribution to forward propulsion. Paired t-tests were used to evaluate differences across time in the involved limb and between limbs postoperatively for power variables. Results: Midfoot dorsiflexion / plantarflexion and abduction / adduction range of motion were not significantly different pre to postoperatively (mean differences &lt; 0.4 degrees; both p &gt; 0.7). Similarly, involved limb midfoot negative and positive power did not change (mean differences &lt; 0.1 W/Kg; negative power p = 0.1; positive power p = 1.0). Postoperatively, negative power was minimally different between sides (mean difference 0.1 W/Kg; p = 0.4). However, involved limb midfoot positive power was 44% less than the uninvolved limb postoperatively (mean difference 0.3 W/Kg; p = 0.1) (Figure 1). Conclusion: Study findings provide preliminary substantiation to the theory that midfoot function is preserved following TAA. At six months, the biomechanical profile of individuals receiving TAA for end-stage ankle arthritis was not different from preoperative measures. Further, since postoperative power absorption was similar between limbs, the current TAA operative approach may help mitigate midfoot joint loading. However, the asymmetrical power generation (44% less on the involved limb) suggests the midfoot is unprepared to respond to anticipated ankle power improvements as patients advance to higher level activities. Accordingly, rehabilitation targeting midfoot stability through strengthening is recommended to complement current postoperative efforts.

Etiology and Biomechanics of Midfoot (Lisfranc) Injuries in Athletes.

Tarsometatarsal (TMT) dislocations are an uncommon but debilitating athletic injury. When symptomatic midfoot instability persists, an injured athlete frequently requires surgical stabilization and rehabilitation for up to 9 months before returning to full athletic participation. Unfortunately, the limited biomechanical knowledge of this injury prevents prophylactic measures from being developed that could reduce an athlete's risk of injury. The goal of this article is to summarize the literature on TMT dislocations, with a particular emphasis on the relevant biomechanics, in an attempt to clarify the circumstances and mechanisms under which these injuries occur. Since athletic injuries represent only a small portion of all TMT dislocations, other categories of injuries are also considered for the insight they provide. This review first summarizes the anatomy of the TMT joint as well as the clinical details surrounding TMT dislocations. The various hypothesized injury mechanisms are then reviewed with particular attention given to cadaveric studies that investigate these mechanisms. Based on this critical review, gaps in the research related to epidemiologic data, full-scale and component testing, numerical modeling, and countermeasure development, are identified. Only by improving our understanding of the causes and biomechanics can steps be taken to protect athletes from these injuries.

Evaluation of the Tarsometatarsal Joint Using Conventional Radiography, CT, and MR Imaging

The tarsometatarsal, or Lisfranc, joint complex provides stability to the midfoot and forefoot through intricate osseous relationships between the distal tarsal bones and metatarsal bases and their connections with stabilizing ligamentous support structures. Lisfranc joint injuries are relatively uncommon, and their imaging findings can be subtle. These injuries have typically been divided into high-impact fracture-displacements, which are often seen after motor vehicle collisions, and low-impact midfoot sprains, which are more commonly seen in athletes. The injury mechanism often influences the imaging findings, and classification systems based primarily on imaging features have been developed to help diagnose and treat these injuries. Patients may have significant regional swelling and pain that prevent thorough physical examination or may have other more critical injuries at initial posttrauma evaluation. These factors may cause diagnostic delays and lead to subsequent morbidities, such as midfoot instability, deformity, and debilitating osteoarthritis. Missed Lisfranc ligament injuries are among the most common causes of litigation against radiologists and emergency department physicians. Radiologists must understand the pathophysiology of these injuries and the patterns of imaging findings seen at conventional radiography, computed tomography, and magnetic resonance imaging to improve injury detection and obtain additional information for referring physicians that may affect the selection of the injury classification system, treatment, and prognosis.

Intramedullary medial column support with the Midfoot Fusion Bolt (MFB) is not sufficient for osseous healing of arthrodesis in neuroosteoarthropathic feet

IntroductionTo address midfoot instability of Charcot disease a promising intramedullary implant has recently been developed to allow for an arthrodesis of the bones of the medial foot column in an anatomic position. We report on a group of patients with Charcot arthropathy and instability at the midfoot where the Midfoot Fusion Bolt had been employed as an implant for the reconstruction of the collapsed medial foot column. Material and methodsA total of 7 patients (median age 56.3 years, range 47–68) were enrolled with severe Charcot deformation at Eichenholtz stages I–II (Sanders and Frykberg types II and III). The medial column was stabilised primarily with an intramedullary rod (Midfoot Fusion Bolt) in stand-alone technique in order to reconstruct the osseous foot geometry. The bolt was inserted in a retrograde mode via the head of MTI and forwarded into the talus. Follow-up time averaged 27 months (range 9–30). ResultsIntraoperative plantigrade reconstruction and restoration of the anatomic foot axes of the medial column was achieved in all cases with the need for revision surgery in 6 out of 7 patients due to soft tissue problems (2 impaired wound healing, 1 postoperative haematoma, 3 early infection). Implant-associated problems were seen in one case intra-operatively with fracture of the first metatarsal shaft and two cases with implant loosening of the MFB and need for implant removal during long time follow-up. Two patients underwent lower leg amputation due to a progressive deep soft tissue infection. One patient healed uneventfully without need for revision surgery. Except for one case recurrent ulcerations were not observed, so far. ConclusionMedial column support in midfoot instability of Charcot arthropathy with a single intramedullary rod does not provide enough stability to achieve osseous fusion. MFB loosening was associated with deep infection in a majority of our cases. To prevent early loosening of the intramedullary rod and to increase rotational stability, additional implants as angular stable plates are needed at the medial column and eventually an additional stabilisation of the lateral foot column where manifest instability exists at the time of primary surgical intervention.

Midfoot Fusion Bolt, a New Implant, and Description of the Technique for Stabilization of Severe Midfoot Instability Including Charcot Foot Reconstruction

Midfoot Fusion Bolt, a New Implant, and Description of the Technique for Stabilization of Severe Midfoot Instability Including Charcot Foot Reconstruction

Stabilization of Joint Forces of the Subtalar Complex via HyProCure Sinus Tarsi Stent

The foot is the foundation of the body. The stability of the osseous hindfoot structure is crucial in bipedal locomotion. The subtalar joint is responsible for conversion of the rotatory forces of the lower extremities and dictates the movements of the midtarsal joints and the forefoot. In a hyperpronated foot, excessive abnormal pronation results in partial to full obliteration of the sinus tarsi. The hypothesis is that the HyProCure device will prevent obliteration of the sinus tarsi, thereby stabilizing the subtalar joint complex and eliminating the excessive forces to the proximal and distal musculoskeletal system that occur with every step. Five fresh-frozen human foot cadaver specimens that represented pathologic hindfoot and midfoot instability and partial to full obliteration of the sinus tarsi were axially compressed to 2,000 N and internally rotated by 15° to produce maximum pronation of the subtalar joint using a biaxial materials testing machine. The forces were measured across the posterior and anterior talocalcaneal joint facets before and after placement of the HyProCure stent. The subtalar joint stabilized after placement of the HyProCure sinus tarsi stent. The mean ± 1 SD forces in the posterior talocalcaneal joint increased from 795.88 ± 106 N to 1,004.86 ± 72.41 N (P < 0.05, two-tailed paired t test). The mean ± SD forces at the anterior talocalcaneal joint decreased from 520.15 ± 127.18 N to 394.56 ± 73.83 N (P < 0.05), shifting the contact area posteriorly. Placement of the HyProCure subtalar stabilization stent in a hyperpronated foot prevents excessive talar subluxation and assists in proper distribution of the axial loads on the subtalar facet joints.

Prediction of Midfoot Instability in the Subtle Lisfranc Injury: Comparison of Magnetic Resonance Imaging with Intraoperative Findings

Prediction of Midfoot Instability in the Subtle Lisfranc Injury: Comparison of Magnetic Resonance Imaging with Intraoperative Findings

Prediction of Midfoot Instability in the Subtle Lisfranc Injury

The objective of the present study was to assess the utility of magnetic resonance imaging for the diagnosis of an injury to the Lisfranc and adjacent ligaments and to determine whether conventional magnetic resonance imaging is a reliable diagnostic tool, with manual stress radiographic evaluation with the patient under anesthesia and surgical findings being used as a reference standard. Magnetic resonance images of twenty-one feet in twenty patients (ten women and ten men with a mean age of 33.6 years [range, twenty to fifty-six years]) were evaluated with regard to the integrity of the dorsal and plantar bundles of the Lisfranc ligament, the plantar tarsal-metatarsal ligaments, and the medial-middle cuneiform ligament. Furthermore, the presence of fluid along the first metatarsal base and the presence of fractures also were evaluated. Radiographic observations were compared with intraoperative findings with respect to the stability of the Lisfranc joint, and logistic regression was used to find the best predictors of Lisfranc joint instability. Intraoperatively, seventeen unstable and four stable Lisfranc joints were identified. The strongest predictor of instability was disruption of the plantar ligament between the first cuneiform and the bases of the second and third metatarsals (the pC1-M2M3 ligament), with a sensitivity, specificity, and positive predictive value of 94%, 75%, and 94%, respectively. Nineteen (90%) of the twenty-one Lisfranc joint complexes were correctly classified on magnetic resonance imaging; in one case an intraoperatively stable Lisfranc joint complex was interpreted as unstable on magnetic resonance imaging, and in another case an intraoperatively unstable Lisfranc joint complex was interpreted as stable on magnetic resonance imaging. The majority (eighteen) of the twenty-one feet demonstrated disruption of the second plantar tarsal-metatarsal ligament, which had little clinical correlation with instability. Magnetic resonance imaging is accurate for detecting traumatic injury of the Lisfranc ligament and for predicting Lisfranc joint complex instability when the plantar Lisfranc ligament bundle is used as a predictor. Rupture or grade-2 sprain of the plantar ligament between the first cuneiform and the bases of the second and third metatarsals is highly suggestive of an unstable midfoot, for which surgical stabilization has been recommended. The appearance of a normal ligament is suggestive of a stable midfoot, and documentation of its integrity may obviate the need for a manual stress radiographic evaluation under anesthesia for a patient with equivocal clinical and radiographic examinations.