Fibula Plating vs Intramedullary K-Wire in Bimalleolar Ankle Fractures

This study was conducted to evaluate and compare the functional outcomes of two commonly employed surgical techniques for the management of bimalleolar ankle fractures: fibula plating and intramedullary K-wire fixation combined with medial malleolar screw fixation. Bimalleolar fractures of the ankle represent a significant portion of ankle injuries and are typically the result of rotational forces acting on the ankle joint. While low-energy mechanisms such as simple falls are common causes, there has been an increasing trend in high-energy trauma, particularly road traffic accidents, which has led to more complex fracture patterns with associated soft tissue injury.

The ankle joint is a highly complex structure composed of osseous and ligamentous components that function together to maintain stability and enable movement. Stability of the ankle depends not only on the integrity of the tibia, fibula, and talus but also on the surrounding ligamentous structures, particularly the deltoid ligament medially and the lateral ligament complex. Any disruption to this osteoligamentous unit can result in joint instability, altered biomechanics, and long-term functional impairment if not managed appropriately.

The deltoid ligament, in particular, plays a critical role in maintaining medial stability of the ankle joint. Injury to this ligament, whether partial or complete, can lead to significant instability, widening of the medial clear space, and potential long-term complications such as chronic pain, deformity, and post-traumatic arthritis. Therefore, a thorough clinical and radiological evaluation is essential in all cases of ankle fractures. Initial assessment should include neurovascular examination to rule out any compromise in circulation, as well as careful evaluation of soft tissue condition, as open fractures or severe soft tissue injury may significantly influence treatment options and prognosis.

Management of bimalleolar ankle fractures is generally surgical, as these injuries are considered unstable. Open reduction and internal fixation (ORIF) has long been considered the gold standard for treatment, particularly for achieving anatomical alignment, restoring joint congruity, and allowing early mobilization. Traditional fibular plating techniques provide rigid fixation and excellent stability; however, they require extensive soft tissue dissection, which may increase the risk of complications such as wound infection, skin necrosis, and delayed healing. These concerns have led to the exploration of less invasive fixation methods.

Intramedullary K-wire fixation represents a minimally invasive alternative that aims to reduce soft tissue disruption while still providing adequate stabilization of the fibula. This technique may be associated with reduced operative time, smaller incisions, and potentially fewer wound-related complications. However, concerns remain regarding the adequacy of fixation strength, maintenance of reduction, and overall functional outcomes when compared to traditional plating methods. Despite increasing use of this technique, there is limited high-quality comparative data evaluating its effectiveness, particularly in relation to early functional recovery.

Given these considerations, the present randomized controlled trial was designed to compare the outcomes of fibula plating versus intramedullary K-wire fixation with medial malleolar screw fixation in patients with bimalleolar ankle fractures. The study was conducted in the Orthopaedic Department of PGMI / Shaikh Zayed Hospital, Lahore, over a six-month period following ethical approval. A total of 200 patients who met the inclusion criteria were enrolled using a non-probability consecutive sampling technique. Inclusion criteria consisted of patients aged between 18 and 60 years of either gender presenting with radiographically confirmed bimalleolar ankle fractures. Patients with compound fractures, associated injuries, or those managed non-operatively were excluded from the study.

After obtaining informed consent, patients were randomly assigned into two equal groups using a lottery method. Group A underwent fibula plating, while Group B received intramedullary K-wire fixation. In both groups, fixation of the lateral malleolus was performed first, followed by fixation of the medial malleolus. All procedures were carried out under standardized surgical protocols with the patient positioned supine and a tourniquet applied after limb exsanguination to provide a bloodless field.

In the fibula plating group, a longitudinal incision was made along the posterior border of the fibula to expose the fracture site. Careful dissection was performed to avoid injury to nearby structures, including the short saphenous vein and the sural nerve. The fracture was exposed, reduced anatomically, and stabilized using a one-third tubular plate. In the intramedullary K-wire group, a less invasive approach was utilized. A small incision was made, and a K-wire was inserted into the intramedullary canal of the fibula under fluoroscopic guidance to maintain alignment and fixation.

The medial malleolus was addressed through an anteromedial approach. The fracture site was exposed, cleared of interposed soft tissue, and reduced anatomically. Temporary K-wire fixation was used to hold the reduction, followed by definitive fixation using a malleolar screw. After completing the procedure, the tourniquet was released, hemostasis was ensured, and wounds were closed in layers. A below-knee plaster of Paris slab was applied in all patients to provide additional support during the early postoperative period.

Postoperative management included administration of antibiotics, limb elevation, and encouragement of active toe movements to prevent stiffness and improve circulation. Sutures were removed on the 14th postoperative day, and patients were followed up regularly. The primary outcome measure was functional recovery, assessed using the Olerud-Molander Ankle (OMA) score at three months postoperatively. This scoring system evaluates ankle function across several domains, including pain, stiffness, swelling, stair climbing ability, use of supports, ability to perform daily activities, and participation in sports. The maximum score is 100, with higher scores indicating better functional outcomes.

The primary objective of the study was to determine whether there was a significant difference in functional outcomes between fibula plating and intramedullary K-wire fixation with medial malleolar screw, as measured by the OMA score. The study was designed with a hypothesis that the two techniques would yield different outcomes, thereby providing evidence to guide clinical decision-making and optimize treatment strategies for patients with bimalleolar ankle fractures.