Weightbearing CT Analysis of the Transverse Tarsal Joint During Eversion and Inversion

Background: Understanding of the movement and function of the transverse tarsal joint (TTJt) continues to evolve. Most studies have been done in cadavers or under nonphysiologic conditions. Weightbearing computed tomographic (WBCT) scans may provide more accurate information about the position of the TTJt when the hindfoot is in valgus or varus. Methods: Five volunteers underwent bilateral weightbearing CT scans while standing on a platform that positioned both hindfeet in 20 degrees of valgus and 20 degrees of varus. Each bone of the foot was segmented, and the joint surfaces of the talus, calcaneus, cuboid, and navicular were identified. The principal axes for each joint surface were determined and used to calculate the angles and distances between the bones with the foot in valgus or varus. Results: In the coronal plane, the angle between the talus and calcaneus rotated 17.1 degrees as the hindfoot moved from valgus to varus. The distance between the centers of the talus and calcaneus decreased 7.1 mm. The cuboid translated 3.9 mm medially relative to the calcaneus. There was no change in angle or distance between the cuboid and navicular. The navicular rotated 25.4 degrees into varus relative to the talus. Conclusion: The TTJt locking mechanism was previously thought to occur from the talonavicular and calcaneocuboid joint axes moving from parallel to divergent as the hindfoot inverts. The current data show a more complex interaction between the four bones that comprise the TTJt and suggests that the locking mechanism may occur because of tightening of the ligaments and joint capsules. Clinical relevance: This study uses weight bearing CT scans of healthy, asymptomatic volunteers standing on valgus and varus platforms to characterize the normal motion of the transverse tarsal joint of the foot. A better understanding of how the transverse tarsal joint functions may assist clinicians in both the conservative and surgical management of hindfoot pathology.

Usefulness of Imaging Techniques in the Diagnosis of Selected Injuries and Lesions of the Canine Tarsus. A Review

Tarsus lesions are not common in dogs, but they can cause serious health problem. They can lead to permanent changes in the joint and, in dogs involved in canine sports, to exclusion from training. The most common diseases and injuries involving the tarsal joint are osteochondrosis, fractures and ruptures of the Achilles tendon. These conditions can be diagnosed primarily through accurate orthopedic examination, but even this may be insufficient for performing a proper diagnosis. Imaging modalities such as radiography, ultrasonography, magnetic resonance imaging or computed tomography can facilitate the detection and assessment of lesions in the canine tarsal joint. This review paper briefly presents some characteristics of the above-mentioned imaging techniques, offering a comparison of their utility in the diagnosis of lesions and injuries involving the canine tarsus.

Free moment induced by oblique transverse tarsal joint: investigation by constructive approach

The human foot provides numerous functions that let humans deal with various environments. Recently, study of the structure of the human foot and adjustment of an appropriate reaction force and vertical free moment during bipedal locomotion has gained attention. However, little is known about the mechanical (morphological) contribution of the foot structure to the reaction force and free moment. It is difficult to conduct a comparative experiment to investigate the contribution systematically by using conventional methods with human and cadaver foot experiments. This study focuses on the oblique transverse tarsal joint (TTJ) of the human foot, whose mechanical structure can generate appropriate free moments. We conduct comparative experiments with a rigid foot, a non-oblique joint foot (i.e. mimicking only the flexion/extension of the midfoot), and an oblique joint foot. Axial loading and walking experiments were conducted with these feet. The axial loading experiment demonstrated that the oblique foot generated free moment in the direction of internal rotation, as observed in the human foot. The walking experiment showed that the magnitude of the free moment generated with the oblique foot is significantly lower than that with the rigid foot during the stance phase. Using this constructive approach, the present study demonstrated that the oblique axis of the TTJ can mechanically generate free moments. This capacity might affect the transverse motion of bipedal walking.

Abnormal Biomechanical Conditions of the Foot in Child with Down Syndrome During Standing: A Finite Element Study

Background: Down syndrome children have a high incidence of pes planus. Pain follows and does harm to their daily life. To well manage their foot pain, it’s necessary to know the mechanism of the pain from the aspect of biomechanics. The purpose of this study was to characterize the abnormal biomechanical conditions of foot in Down syndrome children during standing, comparing to the normal control children by finite element method. Methods: Two participants aged 5 were recruited in this study that are a Down syndrome child with pes planus and a normal control child. Two three-dimension finite element foot models were constructed from CT of the two participants, each of which include bones, ligaments, plantar fascia, cartilages, epiphyseal plates and an encapsulated soft tissue. The plantar pressure during standing and anthropometric data were collected from the same participants for model validation and simulation. Results: The abnormal alignment of the transverse tarsal joint showed in Down syndrome child. The contact pressure in Down syndrome child was higher in tibiotalar joint, compared with the normal control child. The tensile force of spring, plantar calcaneocuboid ligaments in Down syndrome child was approximately 9 folds and 58 folds greater than normal control child, respectively. In Down syndrome child contact force of the talonavicular joint was 0.05 times the body weight and calcaneocuboid joint was near zero, whereas the value in normal control child was 0.11 and 0.01 respectively. Conclusion: The Down syndrome child showed abnormal biomechanical conditions in foot in terms of joints contact pressure, tensile force of ligament around transverse tarsal joint and contact force transmission through transverse tarsal joint. These abnormal biomechanical conditions resulted from pes planus are the potential factors that may cause their foot pain. Conservative interventions should be considered at their early age to eliminate negative effect of these potential factors.

Radiographic Characterization of Midfoot and Transverse Tarsal Joint Osteoarthritis

Category: Midfoot/Forefoot Introduction/Purpose: The burden of midfoot arthritis is staggering. Foot osteoarthritis affects over 16% of all adults over the age of 50, interfering with activities of daily living and leisure. Non-operative management often culminates in fluoroscopic guidance injections. Its management is troublesome for surgeons as conservative treatment is maximized because its surgical solution is oftentimes fraught with nonunions and other complications. The purpose of this study was to see how well surgeons are able to predict midfoot and transverse tarsal joint osteoarthritis on x-rays as it compares to CT and MRI scans. Methods: We reviewed the records of 117 patients (146 feet) with a diagnosis code of midfoot osteoarthritis who were treated from 2015 to 2019 at an academic medical center by a single surgeon. The mean age was 63.2 +- 10.7 years. The average BMI was 31.2 +- 6.4. Each of those patients had both plain radiographs and either a CT or MRI scan. Patients had weight-bearing anteroposterior and lateral radiographs according to a standardized protocol. Radiographs and advanced images were graded separately for the presence of joint space narrowing, subchondral cysts, and other signs of arthritis. We then compared how frequently a radiograph predicted an arthritic midfoot or transverse tarsal joint as compared to a CT scan or MRI using a paired t test. Results: The most common joints affected by arthritis were the 2nd TMT (83.5% by X-ray; 88.4% by CT) and 3rd TMT (71.9% by X-ray; 68.4% by CT). Advanced imaging showed a significantly higher rate of arthritis in the 1st, 4th, and 5th TMT as compared to X-rays. Only 20.2% of patients’ radiographs had a direct correlation with their CT scan. A CT scan showed one or two more affected joints by 23.6% and 17.6 % respectively, and rarely showed one or two less joints affected by arthritis, 6.8% and 0.6% respectively. Based on this data, a radiograph’s sensitivity and specificity vary wildly-from 86.0% and 57.8%, respectfully in the 3rd TMT to 43.8% and 96.0%, respectfully in the 1st TMT. Conclusion: Radiographs vary quite drastically in their sensitivities and specificities in diagnosing osteoarthritic joints in the midfoot and transverse tarsal joints. If intending to treat midfoot osteoarthritis with fluoroscopic injections, we recommend not relying on plain radiographs, but advanced imaging.