Intragrade Intramedullary Nailing of an Open Tibial Shaft Fracture in a Patient With Concomitant Ipsilateral Total Knee Arthroplasty
Open tibial shaft fracture occurring below an ipsilateral total knee arthroplasty (TKA) is a unique injury pattern that presents an additional degree of complexity to an already challenging treatment algorithm. Tibial shaft fracture is a surgical emergency requiring respect for the soft-tissue envelope and consideration of the biomechanical and biologic factors involved in healing. Treatment with an intramedullary nail relative to other types of internal or external fixation methods optimizes these factors and minimizes the risks of nonunion, malunion, infection, soft-tissue compromise, and reoperation, which are prevalent after this fracture. However, tibial shaft fracture associated with an ipsilateral TKA complicates standard treatment principles and increases the risks after surgery. In many instances, this type of injury pattern in a patient with medical comorbidities that would impede fracture and wound healing would make a limb amputation the preferred method of treatment. However, in this case report, we examine treatment options for an open tibial shaft fracture in the setting of an ipsilateral TKA and propose a method of limb salvage in a patient with medical comorbidities sustaining this injury pattern.
Possible complications of this novel method for IM nail passage warrant discussion. First, potentially unfavorable aspects associated with IM reaming include impairment of endosteal blood circulation in the subacute postoperative period.32-34 If the patient develops complications, such as deep infection, nonunion, hardware failure, or periprosthetic fracture, treatment options that require removal of the nail would be very difficult to execute because this nail was passed “intragrade,” or through the fracture site, not from the knee or the calcaneus. However, unique to this case of intragrade nailing, complications associated with the proximal cortical window may occur. In particular, unintended cortical fracture may happen during impaction of the nail into the distal segment of the fracture after reduction. However, this complication may be avoided with the use of a 1-cm wide and 2-cm long window and the use of the malleable aluminum femoral finger (Synthes). Furthermore, use of a femoral nail is recommended because the Herzog curve of a tibial nail cannot be inserted in the proximal tibial segment using an “intragrade” nailing technique. However, fracture may occur intraoperatively or during rehabilitation after surgery because the cortical window creates a region of high stress distal to the tibial arthroplasty component. Likewise, the area of bone between the proximal extent of the IM nail and tibial component of the TKA represents an area of high stress susceptible to periprosthetic fracture.
Conclusion
We have presented a case of a high-energy open distal tibial diaphyseal fracture in a 66-year-old woman with medical comorbidities and treatment complicated by the presence of an ipsilateral TKA. Intramedullary nailing has become the standard of care for open fractures of the tibial diaphysis because of the high rate of union with little additional soft-tissue damage at the fracture site. Despite these advantages, the ipsilateral TKA complicated the placement of an antegrade tibial nail. An alternative treatment, such as an external fixation using an Ilizarov frame, would present equally challenging treatment aspects, including patient compliance, with little proven benefit over an IM nail. Application of a plate would be less desirable because of increased risk of infection at the fracture site, soft-tissue and periosteum disruption, and muscle necrosis compared with other treatment options. Primary amputation was an appropriate consideration for this patient given her comorbid medical circumstances, but the patient refused this treatment option. Therefore, we created a novel approach to place an IM nail, using the traumatic wound to achieve access to the medullary canal proximally and distally.
