Injury to the posterior malleolus in Maisonneuve fractures

PURPOSE

The aim of this study was to describe the incidence and a complex pathoanatomy of posterior malleolus fractures in a Maisonneuve fracture.

METHODS

The study included 100 prospectively collected patients with a complete clinical and radiological documentation of an ankle fracture or fracture-dislocation including a fracture of the proximal quarter of the fibula.

RESULTS

A posterior malleolus fracture was identified in 74 patients, and in 27% of these cases it carried more than one quarter of the fibular notch. Displacement of the posterior fragment by more than 2 mm was shown by scans in 72% of cases. Small intercalary fragments were identified in 43% of cases. Fractures of the Tillaux-Chaput tubercle were identified in 20 patients.

CONCLUSION

Our study has proved a high rate of posterior malleolus fractures associated with a Maisonneuve fracture, and documented their considerable variability in terms of involvement of the fibular notch, tibiotalar contact area, direction of displacement and frequency of intercalary fragments. Of no less importance is a combination of Tillaux-Chaput fractures with a Maisonneuve fracture.

Lateral malleolar crest and its clinical importance

PURPOSE

During study of anatomy of a fractured posterior malleolus of the ankle on CT scans, the authors noticed a prominent crest on the lateral malleolus, which they termed the lateral malleolar crest (LMC). As, in their view, LMC is a clinically important structure which was only briefly mentioned by a few authors without an official term, they focused on the anatomy of this structure.

MATERIALS AND METHODS

A total of 352 dry fibulae were analyzed and the following parameters recorded: (F) length of the fibula, (LMC) total length of LMC, (A) length of the part of the examined crest from the superior border of the articular facet of the lateral malleolus (AFLM) to its most proximal intersection with the midline of the fibula, (B) height of the medial triangular rough surface, and (A/F) A/F ratio.

RESULTS

The crest was observed in all specimens. (F) was 346.5 ± 26 mm (95% confidence interval [CI] 344-349), (LMC) was 85.4 ± 11.6 mm (95% CI 84.2-86.6), (A/F) was 25% ± 3% (95% CI 24.7-25.3) in the whole group. (A) was 25.9 ± 6.5 mm (95% CI 24.8-26.8) in the whole group, (B) was 34.9 ± 4.7 mm (95% CI 34.3-35.5) in the whole group, 36 ± 6.1 mm (95% CI 35.1-36.9).

CONCLUSION

LMC is an important structure on the lateral malleolus. The knowledge of its anatomy is essential for placement of syndesmotic screws or/and the fibular plate.

A fibular notch approach for the treatment of ankle fractures involving the distal tibial plafond

Background

Although efficacy is related to many factors, the surgical approach is one of the most important intervention factors for complex ankle fractures. Ankle fractures involving the distal tibial plafond frequently present a surgical challenge in choosing which incisions will be best for surgical treatment. Here, we present an innovative fibular notch approach for the treatment of some specific ankle fractures and present a series of patients with either functional or radiographic outcomes.

Methods

Twenty-two patients with distal tibial plafond fractures with concomitant fibular and distal tibiofibular syndesmosis injuries were treated through a fibular notch approach in this retrospective study. The details of the surgical technique were reviewed from the operative notes. Relevant data were reviewed from the medical records. The quality of fractures and syndesmosis reduction was examined using CT scans, and lateral stability of the ankle was assessed by physical examination and stress radiographs. The American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS) score was implemented for clinical functional assessment.

Results

All surgeries were successfully performed via the fibular notch approach as the primary approach with excellent intraoperative visualization. Postoperative radiography revealed satisfying restoration of all fractures and syndesmosis. All fractures healed with an average time of 17.3 ± 3.6 weeks. Mild posttraumatic osteoarthritis (PTOA) was present in 4 patients. The average AOFAS score was 88.8 at the last follow-up.

Conclusions

The fibular notch approach is a safe and reliable approach for the treatment of specific ankle fractures involving the distal tibial plafond. This approach provides excellent direct visualization of the fragments and articular surface without significantly increasing iatrogenic injuries. Satisfactory radiographic and clinical results were observed, and further clinical and anatomical studies are recommended to ascertain the feasibility of this approach in the treatment of complex distal tibial fractures.

A standardised computed tomography measurement method for distal fibular rotation

PURPOSE

The aim of the study is to identify an ideal location to measure fibular rotation in the ankle joint using axial computed tomography (CT) scans. Another objective was to detect the average fibular rotation in the uninjured ankle joint in a large cohort.

METHODS

Standardised axial CT with coronal/sagittal reconstructions was performed in healthy ankle joints. Three investigators performed the measurements. In the axial view, each investigator appointed the ideal location to measure the angle of fibular rotation with the use of reference lines either 4, 6, 8 or 10 mm distal from the talar joint line. Inter- and intraobserver reliability, as well as the intraclass correlation coefficient, were determined.

RESULTS

CT scans of one hundred individuals-78 males and 22 females-were analysed. The most common locations for measuring the fibular rotation were in 31% of cases 4 mm and in 51% of cases 6 mm distal the talar joint line. The external rotation of the fibula averaged 8.42° ± 4.86° (range 0°-26°). The intraclass coefficient correlations (ICC) for interrater and intrarater reliability were 0.75.

CONCLUSIONS

The results of the study demonstrate a reproducible location to measure the fibular rotation in the ankle joint. The most convenient location to measure fibular rotation with a high reliability was 6 mm distal to the talar joint line.