Mid-diaphyseal fibular fractures with syndesmotic disruption: should we plate the fibula?

Weber C ankle fractures with tibiofibular diastasis: syndesmosis-only fixation

OBJECTIVES:

To evaluate syndesmosis-only fixation in Weber C ankle fractures with tibiofibular diastasis and to assess the need for additional fibular fixation.

METHODS:

Twenty-one patients with Weber C ankle fractures and tibiofibular diastasis were followed for at least 24 months after treatment. In treatment of the Weber C fractures, only a syndesmosis screw was used through a mini open lateral incision if the syndesmosis could be anatomically reduced and fibular length and rotation could be restored. At follow-up, anteroposterior tibiofibular distance, lateral fibular distance, medial mortise distance and fracture healing were compared and patients were clinically evaluated using the Olerud and Molander ankle scale scoring system.

RESULTS:

The average duration of follow-up was 49 months and the decreases in anteroposterior tibiofibular distance and lateral fibular distance were statistically significant. At the last follow-up the average clinical score was 86. Ankle mortise was reduced at follow-up in all cases except one, which resulted in a late diastasis.

CONCLUSIONS:

Syndesmosis-only fixation can be an effective method of treating Weber type-C lateral malleolar fractures with syndesmosis disruption in cases where intraoperative fibular length can be restored and anatomical syndesmosis reduction can be achieved. Level of Evidence IV, Case Series.

Comparison of modern locked plating and antiglide plating for fixation of osteoporotic distal fibular fractures

BACKGROUND

Fractures in osteoporotic patients can be difficult to treat because of poor bone quality and inability to gain screw purchase. The purpose of this study is to compare modern lateral periarticular distal fibula locked plating to antiglide plating in the setting of an osteoporotic, unstable distal fibula fracture.

METHODS

AO/OTA 44-B2 distal fibula fractures were created in sixteen paired fresh frozen cadaveric ankles and fixed with a lateral locking plate and an independent lag screw or an antiglide plate with a lag screw through the plate. The specimens underwent stiffness, cyclic loading, and load to failure testing. The energy absorbed until failure, torque to failure, construct stiffness, angle at failure, and energy at failure was recorded.

RESULTS

The lateral locking construct had a higher torque to failure (p=0.02) and construct stiffness (p=0.04). The locking construct showed a trend toward increased angle at failure, but did not reach statistical significance (p=0.07). Seven of the eight lateral locking plate specimens failed through the distal locking screws, while the antiglide plating construct failed with pullout of the distal screws and displacement of the fracture in six of the eight specimens.

CONCLUSION

In our study, the newly designed distal fibula periarticular locking plate with increased distal fixation is biomechanically stronger than a non-locking one third tubular plate applied in antiglide fashion for the treatment of AO/OTA 44-B2 osteoporotic distal fibula fractures.

LEVEL OF EVIDENCE

V: This is an ex-vivo study performed on cadavers and is not a study performed on live patients. Therefore, this is considered Level V evidence.

Evaluation of the syndesmotic-only fixation for Weber-C ankle fractures with syndesmotic injury

BACKGROUND

With the length of the fibula restored and the syndesmosis reduced anatomically, internal fixation using a plating device may not be necessary for supra-syndesmotic fibular fractures combined with diastasis of inferior tibio-fibular joint. A retrospective observational study was performed in patients who had this injury pattern treated with syndesmosis-only fixation.

MATERIALS AND METHODS

12 patients who had Weber type-C injury pattern were treated with syndesmosis only fixation. The treatment plan was followed only if the fibular length could be restored and if the syndesmosis could be anatomically reduced. Through a percutaneous or mini-open reduction and clamp stabilization of the syndesmosis, all but one patient had a single tricortical screw fixation across the syndesmosis. Patients were kept non-weight-bearing for 6 weeks, followed by screw removal at an average of 8 weeks. Outcomes were assessed using an objective ankle scoring system (Olerud and Molander scale) and by radiographic assessment of the ankle mortise.

RESULTS

At a mean follow-up of 13 months, the functional outcome score was 75. Excellent to good outcomes were noted in 83% of the patients. Ankle mortise was reduced in all cases, and all but one fibular fracture united without loss of fixation. Six patients had more than one malleolar injury, needing either screw or anchor fixations. One patient had late diastasis after removal of the syndesmotic screw and underwent revision surgery with bone grafting of the fibula. This was probably due to early screw removal, before union of the fibular fracture had occurred.

CONCLUSION

We recommend syndesmosis-only fixation as an effective treatment option for a combination of syndesmosis disruption and Weber type-C lateral malleolar fractures.