Outcomes of tibial pilon fracture fixation based on four-column theory

A systematic review of posterior pilon variant fractures

Posterior pilon variant ankle fractures (PPVF) are a unique subtype of posterior malleolar fractures which have been a source of controversy and confusion in recent years. There has not been a thorough literature review previously written on the topic. Database searches of PubMed and Embase were conducted from inception until June 2023. The key words included "pilon variant," "posterior pilon variant," and "posterior pilon" fractures. Outcomes were evaluated by union time, rates of delayed union, nonunion, malunion, and complication. A total of 15 articles relevant to surgical repair of pilon variant fractures were included in the literature review. The unique mechanism of injury has been reported to involve both rotational and axial forces, leading to involvement of the posterior and medial aspects of the distal tibia. Pilon variant fractures can be suspected by several characteristics on radiographs and have a high confirmation rate via CT images. Multiple systems have been proposed to classify this fracture pattern, but there is no consensus on the ideal classification system. Surgically, direct fixation has shown better short-term clinical outcomes versus indirect fixation or no fixation. PPVF have a distinct fracture pattern involving the posterior and medial columns of the distal tibial plafond, and results from a mechanism intermediate to rotational and axial forces. These fractures are more severe than tri-malleolar fractures due to increased rates of articular impaction and incongruity. Future classification systems should focus on joint surface area and the tibial pilon column involved to avoid confusion with less severe posterior malleolar fractures.

Preoperative temporary fixation for fractures around the ankle using a simple extensible external fixator significantly improves patient comfort

BACKGROUND

The authors developed a simple extensible external fixator, which has the advantages of easy application and inexpensiveness. The present study aimed to make a comparison between this external fixator and calcaneal traction in preoperative temporary fixation for malaligned ankle fractures and pilon fractures.

METHODS

From May 2020 to February 2022, patients with malaligned ankle fractures or Rüedi-Allgöwer type 2 or 3 pilon fractures with obvious soft tissue swelling were retrospectively reviewed and divided into the calcaneal traction group and the external fixation group. The two groups of patients were matched 1:1 before making comparisons.

RESULTS

A total of 38 patients were included. Higher General Comfort Questionnaire score and lower visual analog scale score were noticed in the external fixation group during hospitalization (p < 0.05), while the operation latency time, total cost, patient satisfaction, and functional outcomes one year after surgery were not significantly different between the two groups. No wound complications were observed.

CONCLUSION

Preoperative temporary fixation for fractures around the ankle using this simple extensible external fixator significantly improves patient comfort when compared to calcaneal traction.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Osteoperiosteal Iliac Autograft Transplantation for Unreconstructable Tibial Plafond After Malunions of Pilon Fractures in Young Patients

BACKGROUND

Malunion of tibial pilon fracture, especially with a large cartilage loss of the tibial plafond, is a tough clinical conundrum. This study describes a joint-preserving technique that mainly involves corrective intraarticular osteotomy and osteoperiosteal iliac autograft transplantation for treating these generally considered unreconstructable tibial plafond.

METHODS

Sixteen patients with an average age of 33.6 years who were treated with this joint-preserving method between 2013 and 2020 were retrospectively analyzed. Ankle distraction was applied in all patients. Additional osteochondral autograft transplantation for talus was performed in 4 patients and supramalleolar osteotomy in 2 patients. The visual analog scale (VAS) score, the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, the 36-Item Short Form Health Survey (SF-36) score, and the ankle range of motion (ROM) were used for outcome analysis. Radiographic assessment was conducted, and the complications were recorded.

RESULTS

At a mean follow-up of 41.1 months, the mean VAS, AOFAS, and SF-36 scores improved from 6.3, 47.6, and 38.0 to 1.7, 84.4, and 70.8, respectively (P < .001 for each). The ankle ROM improved from 27.5 to 32.2 degrees (P = .023). The mean area of ilium blocks was 3.5 cm2, and the mean external fixation time was 94.1 days. Radiographs showed that good osteointegration was found in all patients and no significant progression of osteoarthritis in 15 patients. The major complications included poor incision healing in 2 patients and severe ankle stiffness in 2 patients, with one of them developing considerable varus-type osteoarthritis but reporting no pain. No deep infection, nonunion, or malunion occurred, and no secondary arthrodesis was performed during the final follow-up.

CONCLUSION

Osteoperiosteal iliac autograft transplantation might be an alternative surgical option for reconstructing unreconstructable malunited pilon fractures with a large cartilage loss of the tibial plafond in young patients.

LEVEL OF EVIDENCE

Level IV, case series.

Analysis of the Ability of a Distal Tibial Anatomical Locking Plate to Capture the Distal Tibial Fragments in Patients with Pilon Fractures

OBJECTIVE

Although pilon fractures are rare in clinical practice, they are difficult to treat because of their complexity. Effective fixation of the fracture fragment is the key to the treatment of pilon fractures. Plate osteosynthesis is common clinically, but there are many types of plates and the evaluation of the effect of fixation plates is not comprehensive. This study attempted to compare the capture effect of different fixation plates on the fracture fragments based on 3D modeling and fine distinctions of fracture fragments.

METHODS

The computed tomography (CT) images before treatment of 127 patients with pilon fractures from January 2019 to December 2021 were retrospectively collected. The fracture lines were mapped and digitally displayed as 3D images using MIMICS 21 software. APLUS distal tibia anatomical locking plate (Plate A) and ZIMMER distal tibia anatomical plate (Plate B) were placed on a pseudo-bone model and CT scans were used to determine the number of screws in the major and minor fragments of pilon fractures. The frequency of the two plates capturing the fracture fragments was recorded.

RESULTS

Under Assumption 1 or 2, Plate A performed significantly better than Plate B in capturing the major, Chaput, Volkmann, medial malleolus, and die-punch fracture fragments. Plate A captured markedly more minor fragments than Plate B under Assumption 2 but was not significantly different from Plate B under Assumption 1. Plate A or Plate B showed no obvious difference between major and minor capture rates under the same assumption, and A1 or B1 showed a markedly higher capture rate compared with A2 or B2. In addition, there was a significant positive correlation between the major capture rate and the major fragments in B1, and a significant negative correlation between the minor capture rate and the minor fragments in Plates A and B. However, there was no correlation between the major capture rate of Plate A and the major fragments.

CONCLUSION

The APLUS distal tibial anatomical locking plate is superior to the ZIMMER distal tibia anatomical plate in the ability to capture distal tibial fragments in pilon fracture cases.