Flexor digitorum longus transfer with medial displacement calcaneal osteotomy. Biomechanical rationale.

The rationale behind combining a medical displacement calcaneal osteotomy with a flexor digitorum longus (FDL) transfer is to realign the valgus heel under the mechanical axis of the leg and to reduce the deforming valgus moment of the gastrocnemius soleus muscle group on the hindfoot. This reduces the antagonistic force on the relatively weak FDL transfer. This combination has a potential for producing a more mechanically balanced foot and acts as a double tendon transfer in which the Achilles tendon is transferred medially in addition to the FDL transfer, which substitutes for the degenerative posterior tibial tendon.

MRI of injury to the lateral collateral ligamentous complex of the ankle.

We retrospectively evaluated the lateral collateral ligamentous complex of 43 patients who had complained of ankle pain following ankle sprain. The MR signs of ligamentous abnormality included discontinuity or absence, increased signal within the ligament, and ligamentous irregularity or waviness with normal thickness and signal intensity. Using these criteria, 30 anterior talofibular, 20 calcaneofibular, and no posterior talofibular ligament injuries were diagnosed. Compared with surgery (nine patients), MRI demonstrated six of seven anterior talofibular ligament injuries and six of six calcaneofibular ligament injuries. Magnetic resonance showed ligamentous abnormalities in 12 of 23 cases with normal stress radiography. Magnetic resonance imaging provides useful information for the evaluation of patients presenting with chronic pain after ankle sprain.

Treatment of the unstable intertrochanteric fracture. Effect of the placement of the screw, its angle of insertion, and osteotomy.

We created unstable intertrochanteric fractures with a large posteromedial defect in eighteen pairs of fresh-frozen femora from cadavera, and used the femora to evaluate the stability of six combinations of treatment with sliding compression screws and sideplates. The variables that were tested were high (150-degree) angle plates compared with low (130-degree) angle plates, the position of the lag-screw in the femoral head and neck (in the center of the head as seen on both anteroposterior and lateral roentgenograms compared with posteroinferiorly), and whether or not medial cortical contact had been re-established with a limited osteotomy of the greater trochanter. The femora were loaded to the point of failure. The mode of failure, maximum load to failure, and bending rigidity of each method of fixation were measured. Of the six types of treatment, the use of a 150-degree-angle plate, position of the lag-screw in the center of the head as seen on both anteroposterior and lateral roentgenograms, and osteotomy of the greater trochanter resulted in the highest mean load to failure and the greatest rigidity. Over-all, re-establishment of medial cortical contact by means of an osteotomy of the greater trochanter significantly improved the mean load to failure and the rigidity of the fixation. The higher-angle plate, although more difficult to insert, increased the mean load to failure but had no effect on rigidity. The position of the lag-screw (in the center of the head as seen on both anteroposterior and lateral roentgenograms or posteroinferiorly) had no bearing on the mean load to failure, but it significantly affected the mode of failure.