Incidence of lateral talar dome lesions in SER IV ankle fractures.

Osteochondral lesions of the talar dome are commonly the result of ankle trauma. While the technique of surgical repair of ankle fractures has been well reported, there are no studies that correlate the presence or absence of talar dome lesions. A possible explanation for this may be lack of intraoperative inspection of the talar articular surface. This retrospective study evaluates the incidence of lateral talar dome lesions in 50 supination-external rotation stage IV ankle fractures. Specifically, operative reports were reviewed for the presence of lateral talar dome lesions documented through intraoperative inspection. Overall, 19 of 50 fractures, or 38%, were found to have a lateral talar dome lesion. While the bimalleolar and deltoid ligament tear type fractures exhibited more talar dome lesions, there was no significant difference between these two fracture types (p = .1111). There was no statistically significant difference among the three types (unimalleolar, bimalleolar, and trimalleolar) of supination-external rotation ankle fractures (p = .0804). The authors conclude that intraoperative inspection of the lateral talar dome should be a routine part of ankle fracture repair.

Changes in the flexibility characteristics of the ankle complex due to damage to the lateral collateral ligaments: an in vitro and in vivo study.

This study was part of a long-term effort to develop a reliable diagnostic procedure for ankle ligament injuries. Earlier efforts led to the development and validation of a six-degrees-of-freedom instrumented linkage capable of measuring the flexibility characteristics of the ankle complex in vitro and in vivo. The major goal of the present study was to determine if these flexibility measurements are sufficiently sensitive to detect the presence of damage to the lateral collateral ligaments of the ankle joint both in vitro and in vivo. The in vitro testing was conducted on the legs from six fresh cadavers before and after serial sectioning of the anterior talofibular ligament and the calcaneofibular ligament. The flexibility in inversion-eversion, anterior drawer, and internal-external rotation was measured before and after resection of the ligaments. The in vivo testing was conducted on five patients with unilateral injuries to the ankle ligament. The flexibility evaluation used for in vitro specimens was also performed on both the injured and the intact ankles. For the in vitro testing, the data analysis was based on comparison of flexibility values before and after resection of the ligaments, whereas the data analysis for the in vivo testing was based on comparison of the flexibility of the injured joint with that of the intact contralateral joint. The results of the in vitro study indicated that both an isolated rupture of the anterior talofibular ligament and combined damage of the anterior talofibular and calcaneofibular ligaments produce statistically significant changes in flexibility. Furthermore, the most sensitive parameters to the presence of ligament injuries were found to be early flexibility in anterior drawer, early flexibility in inversion, and the amount of coupling between internal rotation and inversion. These parameters provided a basis for differentiating between an isolated injury to the anterior talofibular ligament and a combined anterior talofibular and calcaneofibular ligament injury. For an isolated anterior talofibular ligament injury, a significant increase in flexibility in anterior drawer was present, whereas the increase in inversion flexibility or in the amount of coupling was insignificant. However, the increases in inversion flexibility and the amount of coupling became significant when both ligaments were involved. The results of the in vivo study indicated that significant changes in flexibility can be detected in patients with lateral ankle injuries. Finally, both the in vitro and in vivo results suggest that development of a reliable diagnostic test for ankle ligament injury based on changes in passive flexibility may be possible.

Fifth metatarsal fractures. Biomechanics, classification, and treatment.

Fractures of the fifth metatarsal are treated conceptually based on anatomic location and character of the fracture site. Intra-articular disruptions require reconstruction, if possible. Malalignment of acute fractures requires either closed reduction or open reduction if the malalignment represents a load-bearing dysfunction to the forefoot. Segmental defects require bone grafting and stabilization with plate and screws. Jones fracture is most effectively managed with medullary lag screw delivery in the active or athletic patient. Casting can be considered for high-risk patients. Late bone grafting for sclerotic nonunion is necessary with inlaid grafts harvested from the calcaneus or tibia. Tuberosity fractures require open reduction only when articular involvement is a problem or when distraction is apparent. Otherwise, they can be expected to heal rapidly without long-term problems.