Talar Length Research Articles

Alterações radiográficas do tálus no pé torto congênito após liberação cirúrgica pela técnica de McKay

ABSTRACT Objective: To analyze the morphologic changes of the talus after surgical treatment of congenital clubfoot using the McKay procedure. Methods: We retrospectively analyzed lateral standing radiographs of the feet in 14 patients with unilateral clubfoot treated by the McKay procedure. All patients were operated on by the same surgeon, with an average of 6.53 years between surgery and the radiograph. We compared the characteristics of the talus between the operated foot and the contralateral foot. We evaluated the deformity of the domus and the head of the talus (sphericity evaluation), the talar length and height, the presence and percentage of navicular subluxation, changes in the Gissane angle, and the trabecular pattern of the bone. Results: Deformities of the head of the talus were observed in 92.8% of the patients; of the domus in 92.8%; and of the trabecular pattern in 100%. The ratio between the talar lengths of the operated foot and the contralateral foot ranged from 0.61 to 0.88 (Mean 0.79, SD = 0.09), while the height ratio ranged from 0.57 to 0.98 (Mean 0.82, SD = 0.12). The Gissane angle was increased in all of the operated feet, which also showed some degree of navicular subluxation, ranging from 6.43 to 59.75% (Mean 26.34%, SD = 16.66%). Conclusions: Abnormal talar findings were observed in 100% of the feet treated using the McKay procedure. The establishment of radiographic parameters to describe and quantify these deformities was feasible through simple and easy techniques.

The Role of Ultrasound in Clubfoot Treatment: Correlation with the Pirani Score and Assessment of the Ponseti Method

To evaluate neonates and infants with clubfoot, clinical and imaging modalities are required. Conventional radiography is of limited value because the studied bones are not fully ossified. We attempted to (1) evaluate clinically and sonographically the reliability of the Ponseti method in correcting clubfeet; and (2) determine whether various ultrasound (US) variables correlated with each other and with the Pirani score before and after treatment. We prospectively followed 17 infants (25 clubfeet) assessed using the Pirani score and US variables (medial malleolus navicular distance, navicular alignment in relation to the talar head, medial soft tissue thickness, talar length, and calcaneocuboid distance) and treated with the Ponseti method. The mean age of the patients at first casting was 30 days, and repeat assessment after treatment was performed at a mean age of 6.3 months. Patients were followed for a minimum of 0.75 months (mean, 14.1 months; range, 0.75-38 months). The Ponseti method corrected all feet. We found three clinical/US correlations. Before treatment, we observed a negative correlation between the clinical midfoot score and the sonographic medial malleolus navicular distance. After treatment we observed two negative correlations: one between the midfoot score and the sonographic talar length and the other between the hindfoot score and medial malleolus navicular distance. Four feet had recurrence of varus, two of which had an increased calcaneocuboid distance despite full restoration of navicular alignment in one foot. US can play a role in clubfoot assessment and may alert the surgeon to feet that may be prone to recurrence. Level II, prospective study. See Guidelines for Authors for a complete description of levels of evidence.

Fracturas de la cabeza, cuerpo y apófisis del astrágalo

Introduction Although infrequent, fractures of the talar head and body should be taken in serious consideration because of the severe sequelae they may entail for the function of the foot. Talar head fractures These are usually displaced and involve the talo-navicular joint, which requires a meticulous open reduction, stabilization with screws and sometimes the use of grafts to preserve the talar length; in cases of severe comminution that precludes reconstruction, we believe athrodesis is an efficacious first-line treatment. Talar body fractures These are extremely severe injuries that are characterized by a poor prognosis since they tend to be associated with such sequelae as aseptic necrosis and post-traumatic arthritis, both in the ankle and the subtalar joint. If there is a 2 mm separation they must be considered displaced thus requiring open reduction and fixation with screws, so we must be careful with the technique we select to approach these cases in order not to impair blood supply to the region any further. Fractures of the talar processes During the first examination, these tend to either go unnoticed or be considered minor injuries. Nevertheless, it has lately been shown that their sequelae can enormously disrupt the function of the foot. These injuries should always be suspected since they could easily be mistaken for a sprained ankle, which could have grave consequences not only for athletes but also for other individuals who could even develop an abnormal gait. When in doubt, a computed axial tomography should be carried out and, when appropriate, the fracture must be reduced and fixated. When the above is not possible, it is preferable to excise a fragment than to be faced with a joint incongruency.

Clinical and Radiographic Features of Operatively Treated Stiff Clubfeet after Skeletal Maturity: Etiology of the Deformities and How to Prevent Them

Residual deformities of operatively treated severe clubfeet evaluated radiographically have been rarely studied in detail in adults. Twenty-five operatively treated stiff clubfeet were analyzed at a mean age of 21 years and 6 months. The clinical evaluation used the Laaveg and Ponseti scale for clubfeet. Radiographic assessment was done with weightbearing and dynamic views. Clinical evaluation was globally good except for motion (poor). Radiographic assessment showed residual abnormalities in all feet. The distal tibial epiphysis showed slanting of its posterior part in seven feet (28%) and notching of its anterior lip in 13 (52%). Talar length, calcaneal length, and talar trochlear height were significantly smaller in clubfeet compared to normal feet. Undercorrection of hindfoot varus, was found in 19 feet (76%) but was well tolerated. Navicular wedging was present in seven (28%), and cavus deformity was found in seven (28%). Dorsal bunion, hallux varus, and skewfoot were found in four (16%), two (8%), and three (12%), respectively. The dynamic views demonstrated a significant decrease in the foot and ankle mobility with compensation mechanisms such as anterior talar incongruence or midfoot hypermobility. Severe clubfeet never become normal at adult age either clinically or radiographically. Multiple radiographic deformities exist. Their etiology and possible prevention are discussed. Despite the numerous abnormalities, clinical results were good at skeletal maturity.

Variations in Fibular Position, Talar Length, and Anterior Talofibular Ligament Length

Proprioceptive deficiencies, peroneal muscle weakness, varus hindfoot, and varus tibial plafond have each been implicated as a predisposing factor in recurrent ankle instability. Another predisposing factor for instability is a position of the fibula posterior to the transverse axis of the talus. This study examined the relationship of fibular position and ankle instability with anatomic dissection and magnetic resonance imaging (MRI). Data were obtained from 100 consecutive MRI scans of adult ankles: the malleolar index in degrees and the fibular position anterior or posterior to the anteromedial malleolar plane and relative to the transverse axis of the talus. Twenty cadaver ankles also were studied by MRI and then by anatomic dissection. The malleolar index, the talar length, and the length of the anterior talofibular (ATF) ligament were recorded. The MRI study showed that variation of the malleolar index ranged from 2 to 30 degrees. There was no correlation between the malleolar index and the talar length or the length of the ATF ligament. There is a bell-shaped curve of variation of the position of the fibula relative to the transverse axis of the talus. An ankle mortise with a more posteriorly positioned fibula has less structural stability and is more susceptible to sprain. Neither talar length nor ATF ligament length correlated with fibular position.

Alterations in talar morphology associated with adult flatfoot.

To gain a better understanding on the anatomy of the factors contributing to symptomatic flatfoot, we compared the shape of the talus in feet that were flat to that in control tali from feet with a normal arch. Computed tomographic (CT) scans were performed on 9 adult patients with 10 symptomatic flatfoot deformities. CT scans of 10 feet being evaluated for acute trauma not involving the talus were randomly selected as controls. Flatfoot tali tended to be of greater overall length than the control tali, and this difference was not statistically significant. Statistically significant differences were found when comparing ratios of talar length with talar width (P = 0.011), talar length with talar height (P = 0.001) (they were long relative to their height and width), and head length with head width (P = 0.001) for individual tali from the two groups. The tali from the flatfoot group were narrower in width and shorter in height when compared with overall length and had heads that were more elongated in the transverse plane than tali in feet with a normal appearance. CLINICAL CORRELATION: When performing surgical correction of a flatfoot in an adult, appearance of the foot rather than standard radiographic parameters should be used to judge the reduction. The altered shape of the bone may alter the standard radiographic parameters.