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Is Tension Band Fixation Underutilized For Medial Malleolar Fractures?
Ankle fractures can span from open fractures to isolated fibular fractures. The ankle joint is a complex hinge that includes three separate bones connecting the leg to the foot. As a result, these fractures can be complex and management varies from closed reduction and casting to rigid fixation techniques. One must note that the mechanism of injury of most ankle fractures is rotational in nature. This must be distinguished from distal tibial plafond fractures where the mechanism is usually high-energy impact. One of the most common components of an ankle fracture include medial malleolar fractures. The incidence of medial malleolar fractures is 187 per 100,000 fractures.1 One can sometimes treat isolated and non-displaced medial malleolar fractures conservatively with cast immobilization. However, many individuals undergo open reduction and internal fixation of medial malleolar fractures. Persistent displacement of the medial malleolus can lead to varus tilt of the talus.2,3
Many different medial malleolar fracture patterns exist. Oblique, transverse, vertical and comminuted fractures are the most commonly encountered.1 Many fixation techniques demonstrate excellent outcomes, such as two lag screws, tension band fixation, hook plate and anti-glide plate fixation.1-3 AO recommends lag screws or tension band wiring for the treatment of transverse fractures of the medial malleolus.2 Both constructs allow for absolute stability across the fracture site, leading to primary bone healing.1,2 Tension band fixation has been suggested as the gold standard for the treatment of transverse medial malleolar fractures.3 Recent trends, however, favor the use of two parallel crossing lag screws.
Tension banding converts tensile forces to compressive forces at the fracture site.1 To achieve interfragmentary compression, one applies fixation at the tension side of the fractured bone. This fixation technique results in absolute stability as it allows direct bone healing. Indications include fractures of the olecranon, tuberosity of the humerus, lateral and medial malleolus, and the trochanter of the femur.1 The purpose of this article is to review the relevant literature for both lag screw and tension banding techniques, and to pose the question, “Do we need to revert back to tension band fixation?”
Pertinent Technique Pearls: What You Need To Know
Once we expose and irrigate the fracture site, we can proceed with reduction. It is important to note that in our experience, one must not completely strip the periosteum in order to allow for optimal bone healing. We then insert two 0.062 Kirschner wires (K-wires) perpendicular to the fracture site. These wires must be parallel to each other, purchasing the distal inferior and posteromedial cortices of the tibia. One needs to engage two cortices for effective fixation.
Of note, we utilize two K-wires, as we find this provides rotational stability. In our experience, just using a single K-wire will prompt the fractured bone to rotate. Therefore, it is imperative to use two K-wires to eliminate any rotational forces along the fracture. Often, a fully threaded cancellous screw is inserted just proximal to the fracture site and transverse to the long axis of the tibia. One must be careful to avoid inserting this screw in to the tibiofibular joint. Moreover, the senior author prefers to have bicortical purchase, particularly in osteoporotic bone. We then bend the ends of the K-wire and apply a 22-gauge tension band wire in a figure-of-eight configuration. A pertinent pearl that one can utilize is to avoid twisting one wire around the other. Rather, a double helix structure is preferrable. We continue to tighten the wire is tightened until achieving adequate compression at the fracture site. The wires are bent flush against the superior medial surface of the medial malleolus.
What Does The Literature Reveal?
Classically, tension band fixation was the gold standard to treating avulsion fractures In extremities. However, we have observed a recent trend utilizing two cannulated parallel lag screws for fixation of medial malleolar fractures.
Ostrum and colleagues conducted a prospective study on tension band fixation of medial malleolar fractures on 30 consecutive patients, reporting no non-unions or displacement of wires postoperatively.3 Only one complication occurred where a fragment had two mm of displacement after fixation, but did progress to union. The authors performed a comparative study of K-wires, K-wires with tension band and two cancellous screws. Their biomechanical study found that tension band fixation provided the greatest resistance to pronatory forces.3 The tension band construct was also four times stiffer than using two screws.3 The authors concluded tension band fixation to be biomechanically stronger than utilizing cancellous screws.3
Mohammed and team also conducted a comparative study in fixation methods of medial malleolar fractures between tension band wiring and screw fixation.4 The group undergoing tension band fixation showed quicker union time (9.4 weeks) compared to screw fixation (11.8 weeks).4 Moreover, the tension band fixation group reflected better scores on the modified ankle scoring system of Olerud and Molander.4
Ebraheim and colleagues conducted a large study of 111 medial malleolar fractures.1 Their study compared treatment of vertical, transverse, oblique and comminuted fractures with buttress plate, lag screw, tension band or K-wire fixation.1The authors found that tension band fixation showed the highest rate of union, highest average AOFAS score, lowest revision rate and lowest complication rate.1 It is important to note that the use of two lag screws also showed similar favorable outcomes. However, tension band fixation required less need for revision surgery.1
Lastly, we conducted a yet-unpublished cost study at our institution regarding the use of cannulated screws versus a tension band construct for medial malleolar fractures. Utilizing a 1.25mm coil wire and one 4.0 cancellous screw equated to billable cost of $71.01. Conversely, the cost of utilizing two cannulated 4.0 cancellous screws equated to $318.00. Therefore, we found this technique is 4.5 times less expensive than the use of cannulated screws. Please note that these prices may vary at different institutions.
Concluding Thoughts
Tension band fixation is an under utilized standard of treatment for medial malleolar fractures. This construct, historically described as the technique of choice for surgically treating avulsion fractures, helps correct rotation, alignment and length along the fracture site. Recently, many surgeons seem to prefer using cannulated screws for fixation of medial malleolar fractures. We hypothesize that this may be due to easier surgical technique and individual surgeon preference. A deeper dive into the topic poses the question, “Do we need to revert back to tension band fixation as the gold standard?” Studies certainly show lesser complications, quicker union rates and an overall favorable prognosis with this construct.
Dr. Kissel is board-certified by the American Board of Foot and Ankle Surgery and is in practice in Southeast Michigan.
Dr. Shamim is a second-year podiatric resident at Detroit Medical Center in Detroit.
Dr. Dandashlii is a third-year podiatric resident at Detroit Medical Center in Detroit.
- Ebraheim NA, Ludwig T, Weston JT, Carroll T, Liu J. Comparison of surgical techniques of 111 medial malleolar fractures classified by fracture geometry. Foot Ankle Int. 2014;35(5):471-477.
- Barbosa P, Bonnaire F, Kojima K, Demmer P. Malleoli reduction and fixation. AO Foundation. 2006. Available at: https://www2. aofoundation.org/wps/portal/surgery?showPage=diagnosis& bone=Tibia&segment=Malleoli. Accessed May 19, 2021.
- Ostrum RF, Litsky AS. Tension band fixation of medial malleolus fractures. J Orthop Trauma. 1992;6(4):464-468.
- Mohammed AA, Abbas KA, Mawlood AS. A comparative study in fixation methods of medial malleolus fractures between tension bands wiring and screw fixation. SpringerPlus. 2016;5:530.