Techniques for the selective cutting of ligaments in cadaver knees defined the static contributions of the posterolateral structures to external rotation, varus rotation and posterior tibial translation from 0° to 120° of flexion under defined loading conditions.

Sectioning of the popliteofibular ligament (PFL) (group 1) produced no significant changes in the limits of the knee movement studied. Sectioning of the PFL and the popliteus tendon (femoral attachment, group 2) produced an increase of only 5° to 6° in external rotation from flexion of 30° to 120° (p < 0.001). Even when other ligaments were sectioned first (group 3), the maximum effect of the PFL was negligible.

Our findings show that the popliteus muscle-tendon-ligament complex, lateral collateral ligament, and posterolateral capsular structures function as a unit. No individual structure alone is the primary restraint for the movements studied. Operative reconstruction should address all of the posterolateral structures, since restoration of only a portion may result in residual instability.

Introduction: Treating tibial plateau fractures extreme care should be given to restore articular surface height preserving knee joint stability to be able to obtain maximal range of movement and to prevent future joint degenerative changes. Preoperative evaluation with CT and 3-D reconstruction is mandatory to understand the topography of the fracture for surgical planning. Traditional bone grafting techniques together with newer bone substitutes should be utilized in addition to ligamentotaxis when necessary. Fixation with smooth or olive wires (in occasions with washers for wider contact), sometimes augmented by screws is used with the Ilizarov external frame for stabilization avoiding extended incisions. In unstable fractures, bridging of the knee with slight distraction of the joint is provided by including the distal femur to the frame with an additional ring. Guided by these principles, complex tibial plateau fractures were treated in our department and the results are reported.

Materials and Methods: Ten patients 40.6 years old on average (30–70) with Schatzker type V–VI fractures (all closed) were treated by hybrid 3 ring Ilizarov external frames alone or in combination with another procedure. Six were treated by ligamentotaxis and Ilizarov fixation alone and minimal opening for joint surface elevation when needed. The remaining 4 needed 6.5 mm canulated cancellous screw augmentation and 2 of them additional bone graft supplementation. Two patients needed extension of the frame to the femur with hinges on the center of joint rotation. All patients remain non-WB for 6 weeks and partial WB for another 6 weeks. Within 3 months the frame was removed and replaced by a brace or a cast-brace with full WB. Physiotherapy started early after the operation.

Results: The results were analyzed over an average follow-up period of 22.6 months (range 3–53). All fractures healed in an average of 12 weeks. Range of motion in all patients included full extension with 90° of flexion or more. No postoperative infections, septic arthritis or neurovascular complications were reported. Pin site infection was resolved locally. One case resulted in mild valgus alignment due to osteoporotic bone (70 years old patient).

Discussion: Ilizarov external fixation for complex tibial plateau fractures offers the advantage of minimal invasive interventions with a high level of functionality since the early post operative period. The combination with minimal invasive opening for joint surface elevation and additional screws or bone graft extends even more the scope of the treatment. Functional results were similar to previous reported series. The good observance of traditional tibial plateau surgery principles should guide the surgeons when using this modality of treatment for optimal results.

Studies derived from analyses of radiographs and dissections of cadaveric wrists have been directed at testing and disproving the commonly held theories that link chip fractures of the os triquetrum with avulsion. The authors found that the mechanism of such injuries involved a chisel action of the ulnar styloid upon the dorsum of the os triquetrum; furthermore, the impact of a fall on the outstretched arm with the hand rigidly held in strong dorsiflexion and ulnar deviation could be forceful enough to fracture the body of the os triquetrum as well. In all cases a striking prolongation of the ulnar styloid, beyond the surface of the ulnar head, was consistently noted.

1. A case of bilateral spontaneous and simultaneous rupture of the quadriceps tendons is described.

2. The underlying cause was found to be gouty affection of the tendons.

3. So far as is known, a similar case has not previously been recorded.

1. Three cases of paralysis of the radial nerve after intensive muscular effort in extension of the elbow are described. Clinical and electrophysiological evidence is recorded.

2. There was motor and sensory affection of varying degree and extent in the distribution of the radial nerve.

3. The type of lesion in each case was that of neurapraxia, and rapid spontaneous recovery occurred in each case.

4. The level of the lesion was in the arm, below the origin of the branches to the triceps.

5. The cause of the lesion was thought to be compression by a fibrous arch related to the lateral head of the triceps.

6. The cases are discussed in relation to other instances of compression of nerves by fibrous arches, and an explanation is advanced for spontaneous recovery.

1. Three cases of the Laurence-Moon-Biedl-Bardet syndrome occurring in a Yemenite family are presented. The parents were first cousins.

2. In two of the patients the complete syndrome, which comprises retinitis pigmentosa, polydactyly, obesity, genital hypoplasia and mental retardation, was found. The patients also had abnormalities of the hips.