Vertical talus presents with which of the following x-ray changes?(B) Dislocated navicular
Congenital vertical talus presents as the talus fixed in a vertical position with hypoplasia of the talar neck and head.
and articulates with the dorsal aspect of the talar neck
. The tibionavicular
and dorsal talonavicular
ligaments are contracted preventing reduction of the navicular.
Congenital vertical talus is a complex deformity involving bone, tendon, capsule, and soft tissue abnormality. It has a similar appearance at birth to talipes calcaneovalgus, but there is lack of motion at the subtalar joint
and ankle joint within 6 months
after birth, a negative
calcaneal inclination angle, and complete dislocation of the talonavicular joint
. It cannot
be reduced with serial casting.
What iatrogenic problem can occur with derotational casting for clubfoot by aggressive dorsiflexion for the equinus component?Vertical Talus.
How is congenital calcaneovalgus deformity easily distinguished from congenital convex pes plano valgus deformity on clinical examination?Congenital calcaneovalgus is flexible and allows for passive correction.
- CONGENITAL VERTICAL TALUS A.K.A.Congenital Convex Pes Plano Valgus.Reverse Clubfoot. Persian Slipper.Rockerbottom Flatfoot)
- DESCRIPTION-Primary dislocation of the navicular dorsally on the neck of the talus locking the talus in a vertical position-Forefoot is abducted and dorsiflexed at the midtarsal joint-Calcaneus is in valgus and equinus-RIGIDITY is the hallmark of the deformity -Contracted gastrocsoleus, and elongated spring ligament-Majority B/L-R>L-Often occurs with other congenital deformities most notably Arthrogryphosis-Foot may actually touch the front of the tibia at birth-Walking is not delayed because the condition is not painful in childhood, however gait is awkward, clumsy and almost peg-like and shoes may be difficult to wear-Talar head is prominent on medial plantar aspect of foot and may have a callus over it from bearing most of the body weight-STJ facets are abnormal Anterior-absent Middle-hypoplastic Posterior-malformed(misshapen)
- RADIOGRAPHIC EVALUATION-Definitive diagnosis is determined by taking a lateral x-ray and comparing it to a second lateral x-ray with the foot maximally plantarflexed demonstrating that the talonavicualar relationship does not change. Navicular is not evident radiographically until age 3 so it is difficult to establish its subluxation.-Line bisecting talus(on lateral x-ray) is parallel to tibia-Talocalcaneal angle on A/P is increased, usually > 40°-Talar neck is hypoplastic and so may have an hourglass shape and may have a flat surface-Navicular articulates with the dorsal neck of the talus-(-)Hubscher maneuver
- TREATMENT CLOSED REDUCTION-rarely successful-Manipulation and casting is recommended as a means of stretching the soft tissues for future definitive surgical treatment in an attempt to avoid skin sloughing
- OPEN REDUCTION 3 MONTHS-3YEARS-If closed reduction fails, open reduction should be performed at 3 months of age-Many procedures have been described, they all involve a posterior release and reduction of the talonavicular joint 3-6YEARS-In addition to open reduction an extra-articular arthrodesis(Green-Gricetype) or arthroereisis may be attempted to maintain reduction and stabilizethe STJ 6 YEARS AND UP-At this point it's best to postpone surgery until skeletal maturity(10-14years of age) at which time a triple arthrodesis is performed which may require removal of the head and neck of the talus to obtain reduction
Congenital Vertical Talus (Congenital Convex Pes Valgus, Rocker Bottom Foot)-this idiopathic anomaly, a form of clubfoot, is characterized by a foot that may actually contact the pretibial surface at birth. The plantar surface is convex (rocker bottom), and the talar head can be identified on the medial plantar aspect of the longitudinal arch, with the hindfoot in equinovalgus. Deforming muscle groups displaying contracture include- gastrosoleus complex (ankle equinus); ankle dorsiflexors (TA, EDL, EHL.) and the peroneal tendons; and the peroneal and tibialis posterior are relatively more anteriorly migrated than normal. Ligamentous shortening involves the dorsal talonavicular, tibionavicular,calcaneofibular, calcaneal-cuboid, interosseous talocalcaneal ligaments; and the posterior AJ and STJ capsules are tightened. The spring ligament, conversely, is elongated.Radiographic evaluation employs use of the Ap, lateral and forced plantarflexion views(Figure 9-11 ).In the lateral view, the long axis of the talus appears vertical and parallel to that of the tibia while the calcaneus is in equinus and the forefoot dorsiflexed. In the AP view,the TCA is increased to >400 The navicular cannot be radiographically evaluated until 3-4years of age, when it ossifies. When it has ossified, the navicular is identified in a dorsallydislocated position. The stress plantarflexion latera l view allows comparison of the firstmetatarsal on standard lateral and the stress view, so that rigidity of the deformity can bedetermined. Normally, the talar and first metatarsal axes are parallel; however in thepresence of a rigid plantarflexed talus, the talar axis passes through sole of foot and the firstmetatarsal ax is passes dorsal to head of talus. In the forced plantarflexion view, thisrelationship will not be reduced. Convex pes valgus is categorized as either Type I or TypeII. Type I involves dislocation ofthe TNJ, subluxation ofthe TCJ, and a normal CCJ. Type IIis more rigid and involves dislocation ofthe TNJ, subluxation of the TCJ and CCJ, and ankleequinus. The differential diagnosis for calcaneovalgus includes talipes calcaneovalgus,severe pes valgoplanus with gastrosoleus equinus, paralytic pes valgoplanus,myelomeningocele, polio, and rigid pes valgus due to tarsal coalition. Associateddeformities include cleft palate, arthrogryposis, and spastic equinus due to CP and others.Treatment of congenital vertical talus focuses on restoring the normal TN, TC, andCCJ relationship as soon as possible. This condition is notoriously res istantto nonsurgicaltreatment As with ta lipes equinovarus, manipulation and serial corrective casting(Ponsetti method) are useful. At birth, gentle manipulation is used to stretch the contractedsoft tissues. Manipulation entails stretch oftriceps surae and calcaneofibular ligament viadistal and medial traction, plantarflexion and adduction of the FFto stretch dorsiflexors andeverters, and distal traction of the FF and TNJ to effect adductus and varus stretch of thetibionavicular and talonavicular ligam ents. The stretch is held for 15 seconds and thenreleased, and the exercise is continued for 15 minutes after which the cast is applied. Thecast is changed twice per week for six weeks. As correction ensues, focus more on TNreduction by means of distal FF traction until the head of the talus dorsiflexes and thecalcaneus is pulled under the ta lus. It may become necessary to maintain the closedreduction with percutaneous pin stabilization. If, after 4-6 months of closed reduction,Figure 9.11Ch.9 Congenital Deformities and Juvenile Surgery 241impasse is reached, then open reduction should be performed. The longer the TNdislocation persists, the more the soft tissue contracture deforms bone and surroundingjoints. Surgical repair of congenital vertical talus employs a medial, curvilinear skinincision extending from the medial aspect ofthe Achilles tendon at a point 4-6 cm proximalto the ankle, around the tip of the medial malleolus, and onward to the junction of the firstmetatarsal and medial cuneiform. The neurovascular bundle is retracted, after which theAchilles, TA, EHL, and peroneal tendons are Z-plasty lengthened. The tibionavicular, TN,bifurcate, and dorsal calcaneocuboid, calcaneofibular and TC interosseous ligaments arethen sectioned. The talar head is manipulated dorsally and the navicular moved in aplantar direction with inversion. A smooth 0.062" K-wire is then driven from the posterioraspect ofthe talus across the reduced TNJ, and continued anteriorly across the NCJ. Thespring ligament is then reefed tightly, and an AK cast used to maintain the correction for12-16weeks. The K-wire can be removed around 6 weeks postop. Avascular necrosis ofthetalus is a possible complication. Excision of the navicular has been effective in the treatmentof rigid arthrogryposis in patients 3-6 years of age. In children >6 years old, rigid bone andjoint adaptation may indicate the need fortriple arthrodesis.