A Closer Look At Arthroscopy For Ankle Fractures And Post-Fracture Defects
Arthroscopy is an expedient tool in the management of intra-articular fractures of the ankle and post-fracture articular defects. It provides the surgeon the ability to anatomically reduce a fracture under direct visualization with minimal intervention. It also enables the surgeon to address any articular injury primarily.
The AO philosophy has remained consistent and clear. When it comes to patients with displaced, unstable ankle fractures and related problems, we strive for operative anatomic reduction and stabilization designed to bring an early return to mobility and function. Is this enough? Can one treat the injured articular surface in conjunction with osseous reduction and fixation?
New evidence is shedding light on the fact that almost 80 percent of malleolar fractures have a concomitant chondral or osteochondral defect.1,2 Historically, there has been significant attention in the literature on the management of chronic osteochondral lesions of the tibiotalar joint and their treatment outcomes.
As surgeons who manage patients with this pathology, we know osteochondral lesions of the talus are often missed and treatment can be delayed for months and often years. If we are to subject the patient to an operation for the ankle fracture, why not evaluate and primarily treat the associated intra-articular pathology that is known to be a cause of chronic ankle dysfunction?
The established AO principles of anatomic reduction with internal fixation are well known to the foot and ankle surgeon. Intra-articular incongruity is one of the main reasons fractures are surgically addressed. The tibia takes approximately five-sixths of the load at the ankle joint and patients tolerate articular malreductions poorly.
With certain fracture types and patterns, accurate anatomic reduction can be difficult to obtain without significant soft tissue disruption. Accomplishing this anatomic reduction by the least invasive yet still effective means is a matter of increasing concern. This is especially true given the complications that can ensue, especially in the geriatric and diabetic patient population. Arthroscopic assisted fracture reduction can provide a less invasive operative reduction of the fracture and respects the soft tissue envelope.
Fractures about the ankle that are amenable to arthroscopic assisted reduction and fixation include:
• medial malleolar injuries;
• posterior malleolar injuries;
• Tillaux fractures;
• triplane fractures; and
• tibial plafond fractures.
What about the case of the patient who has persistent pain several months after the fracture has healed? This persistent pain can be attributed to intra-articular pathology as previously discussed. The patient who was treated operatively or non-operatively can have fibular malunion. Chronic syndesmotic instability can also be the source of ongoing pain. Arthroscopy in conjunction with intra-articular debridement and/ or osseous realignment procedures can benefit all of these patients.
Utsugi and colleagues published a paper on 40 patients who underwent ankle arthroscopy one year after the index procedure.3 Almost a third of the patients required a functional derotation of the ankle joint. Arthroscopy showed articular cartilage damage in 33 percent of patients and arthrofibrosis in 73 percent. Furthermore, 89 percent of patients with functional derotation of the fibula and combined arthroscopic debridement showed improved articular function.
Keys To Initial Assessment And Patient Management
One should obtain standard radiographic views of the ankle for the initial assessment of the fracture pattern. Computed tomography (CT) of fractures is sometimes warranted when extensive comminution or intra-articular involvement is present. This aids in preoperative planning of fracture surgery. If there is high fibular tenderness, obtain a tibia-fibula series in order to include the ankle and knee joints. Obtain foot X-rays when the clinical exam warrants.