Failed proximal femur fracture fixation with Broken Cephalomedullary Nails: Outcomes of Conversion Total Hip Arthroplasty Using a Monoblock Tapered Fluted Revision Stem

When a bone in the upper leg breaks, surgeons often repair it by inserting a long metal rod that runs down the center of the bone, anchored near the hip joint. This rod, known as a cephalomedullary nail, acts as an internal splint, holding the broken pieces together while they heal. However, in some cases, the metal rod itself snaps under the stress of daily movement, leaving the patient with a broken implant and a broken bone that has failed to heal. This creates a difficult situation for elderly patients who need to walk again. The bone around the break is often damaged, and the usual methods for replacing the hip joint cannot be used because the top part of the leg bone is too compromised to hold a standard replacement. The medical community has long sought a reliable way to fix these specific, complex failures without causing new problems or requiring further surgeries.

A team of surgeons in Italy recently examined how well a specific type of revision surgery works for these exact cases. They focused on twenty patients who had suffered a broken metal rod inside their hip and underwent a conversion to a total hip replacement. Instead of using a standard hip stem, the surgeons used a special, solid metal rod designed to bypass the damaged upper section of the bone entirely. This new rod, which is tapered and fluted to grip the inner walls of the bone shaft, was inserted deep into the healthy lower part of the femur. The researchers wanted to see if this approach could provide a stable foundation for the new hip joint and allow patients to regain mobility, even when the upper bone was in poor condition.

The study followed these patients for an average of over two and a half years. The results showed that the special metal rod held firm. None of the stems shifted, loosened, or required replacement during the observation period. The surgeons were able to restore the natural mechanics of the hip, ensuring the leg length and the angle of the joint were correct. While the metal rod provided a solid anchor, the surgery was not without challenges. The upper part of the bone, where the muscle that lifts the leg attaches, was often unstable. In most cases, the surgeons had to use strong cables to reattach this muscle to the bone. Despite the complexity of the operations, the primary goal of securing the new hip joint was met. No stem failed, and no patient needed a second surgery to fix the metal rod itself.

Complications did occur in six of the twenty patients, highlighting the difficulty of these procedures. Three patients experienced a dislocation of the new hip joint within the first two months, and two of them required additional surgery to stabilize the joint. One patient suffered a fracture of the metal rod during the initial operation, which was fixed immediately, and another broke their leg far below the implant years later after a fall. A small number of patients also had a collection of blood under the skin that required drainage. However, none of these issues led to the failure of the main metal rod. The researchers found that the success of the surgery in terms of pain relief and movement was not determined by the patient's age, but rather by their overall physical health before the operation. Patients who were in better physical condition before the surgery tended to have better outcomes afterward.

The findings suggest that using a solid, uncemented metal rod that grips the deep, healthy part of the bone is a reliable way to reconstruct the hip after a broken internal nail. This method avoids the need for cement, which can be difficult to apply when the bone is damaged, and eliminates the weak points found in some modular implants. While the surgery is demanding and carries a risk of complications like dislocation, the core structure of the new hip remains stable. For patients facing this specific type of failure, the study indicates that a well-planned reconstruction using this specialized stem can offer a durable solution, allowing them to return to daily activities, provided their overall health supports the recovery.