Overview of Surgical Management of Femoral Neck Fractures
A femoral neck fracture (FNF) is a break that happens where the long part of the thigh bone and its head meet. This kind of break can be a big problem. It’s a break in an important place, and it can really affect someone’s ability to move and their overall health. FNFs are more common in older people and can even be deadly — about 36% of people with this type of fracture pass away within a year.
These fractures also cost a lot to treat, which has a big impact on all of society. FNFs can happen in two main ways. They can happen to older people from low-impact injuries (like a fall), or to younger people from high-impact trauma (like a car crash).
But most FNFs happen to older people, especially those who have osteoporosis, are female, smoke a lot, or don’t weigh very much. Doctors need to understand all the ways FNFs can be treated surgically so they can help their patients the best they can.
Anatomy and Physiology of Surgical Management of Femoral Neck Fractures
The hip joint is kind of like a ball-and-socket, formed where the femur (thigh bone) links with the pelvic bone. This joint allows a wide range of movements like bending, stretching, moving the leg inward and outward, and even rotation. The ‘neck’ of the femur plays a crucial part in this, acting like a bridge between the ‘head’ of the femur and its main body or shaft. This part of the bone is quite prone to fractures, especially in elderly people who have osteoporosis, which is a condition where the bones become weak and brittle.
About half of all hip fractures take place within the joint capsule, which is a kind of pocket surrounding the joint. People with osteoporosis are especially prone to this type of fracture. It’s important to distinguish these fractures, as they have limited healing potential because they lack blood supply and mainly rely on the nutritional fluids present in the joint for upkeep. When an in-joint fracture occurs, it’s critical to maintain the integrity of the joint pocket, as any damage might disrupt the blood supply to the femur’s head and lead to even more complications.
The blood supply for the head of the femur comes from three main places. First, an artery known as the ‘profunda femoris’ splits into smaller arteries which are critical to the femur head’s health. Next, there’s the ‘ligamentum teres’, a primary blood source that plays a bigger role in childhood and dwindles in importance as we age. Lastly, minimal blood supply comes from the bone’s internal canal and the inferior gluteal artery.
People who have these in-joint fractures run the risk of developing avascular necrosis (AVN), a condition that cuts off the blood supply to a section of bone and can lead to bone collapse if not addressed. The hip joint’s nerve supply stems from branches of the femoral, obturator, and sciatic nerves, which control sensation in the joint and movement in the surrounding muscles.
If these in-joint fractures occur in older people and are displaced (i.e., the bones are no longer aligned), the femur’s head and neck are often replaced with an artificial part. This procedure, called hip hemiarthroplasty or total hip arthroplasty (THA), is usually adopted. For fractures where the bones are still aligned, the injury might be stabilized using screws.
On the other hand, fractures outside the joint capsule aren’t likely to disrupt the blood supply to the femur’s head and neck. Therefore, a wider range of surgical methods could be used to treat these injuries. The likelihood of femur head AVN is quite low in the case of these fractures.
Why do People Need Surgical Management of Femoral Neck Fractures
If one has a femoral neck fracture (FNF), which is a break in the bone right below the ball of the hip joint, it requires proper care by a team of healthcare professionals. Usually, surgery is most helpful to fix the broken bone, helps in managing pain, allows for better movement, and enables the bone to heal.
However, for those who cannot walk and have significant existing health problems, surgery may not be the best solution. In these cases, the focus is on managing pain and gradually moving as much as possible. If the patient cannot walk at all, they may experience pain likely caused by a pelvic bone issue. Immediately after the injury, it’s important to control pain and keep the body steady. Attempts at moving around are possible once the body has started repairing the bone, which often happens a few weeks after the injury. However, avoiding surgery can increase the chances of lung problems, pneumonia, urinary tract infections, pressure sores (like sacral decubitus ulcers), deep vein thrombosis (DVT), and venous thromboembolism (VTE) due to long periods of immobility.
For those who undergo surgery for FNFs, there are different procedures that can be performed, where each procedure depends on the patient’s condition. A Hip Hemiarthroplasty or femoral head replacement, helps in treating displaced FNFs, typically in older patients who are not very active. Total Hip Arthroplasty (THA) is another procedure preferred in patients who can easily move around or are experiencing hip pain and arthritis. Dual mobility cups can be used in THA in active older people to improve their functional results. Girdlestone Resection Arthroplasty, another option, could be performed if there’s a systemic infection or severe neurological impairment – although it has fewer benefits than the Hemiarthroplasty.
In older patients with a non-displaced or still in place FNF, a procedure called Cannulated Screw Fixation can be performed. This is also applicable to younger people with excellent bone quality and displaced fractures. The procedure involves the insertion of 3 or 4 screws in a specific pattern that help keep the fracture secure. However, the treatment’s success might be similar whether internal fixation or arthroplasty is performed.
Another surgical option is the Sliding Hip Screw (SHS) Fixation. This involves a large screw that goes from the side of the thigh bone, across the fracture, and ends near the center of the ball of the hip joint. This screw can slide inside a metal sleeve connected to a fixation plate, which is then secured with multiple screws to the thigh bone’s upper part. This kind of fixation is beneficial for stable hip fractures, basicervical FNFs, and vertical FNFs. As the patient walks after the surgery, the fracture compresses down as the screw slides into the barrel, which helps in healing.
When a Person Should Avoid Surgical Management of Femoral Neck Fractures
For some types of hip fractures, a procedure known as a sliding hip screw fixation is not recommended. The reasons for this include:
- Reverse obliquity: This is a type of fracture where the break runs diagonally from top to bottom, which can make the bone unstable.
- Transtrochanteric involvement: This means the fracture goes through a specific part of the hip bone, possibly making it unstable.
- Comminuted fracture patterns with a large posteromedial fragment: In plain English, this means the bone is broken into many pieces, with one large fragment at the back of the bone. The absence of a part known as the medial calcar buttress makes the fracture unstable.
- Fracture patterns with subtrochanteric extension: This is a fracture that extends to a specific part of the thigh bone located below the hip joint.
A procedure called Hemiarthroplasty or Total Hip Arthroplasty (THA), both involving a partial or full hip replacement, is not recommended if a patient has an active infection in the hip.
Equipment used for Surgical Management of Femoral Neck Fractures
All surgeries involving the femoral neck, which is the part of your thigh bone closest to your hip, need a certain set of surgical tools that are typically found in an orthopedic tray. These surgeries should be done in a special operating room that has a system known as laminar flow, which helps keep the air clean and reduces the risk of infection.
For certain types of surgeries, like using cannulated screws (hollow screws) and sliding hip screws (SHS) to fix fractures, some additional things are necessary. These include the screws themselves, a special type of table that allows for certain positions and movements, and a machine known as an image intensifier that gives the surgeon a clear picture of the area they’re working on.
For other types of surgeries such as partial hip replacement (hemiarthroplasty) and total hip replacement (THA), a standard operating table can be used if it has the necessary extensions. A full set of hip replacement parts is needed, along with any tools and materials needed for secure attachment of these parts, sometimes involving cement. Recently, computer guidance and robotic assistance are being used more and more in hip replacement surgeries.
Who is needed to perform Surgical Management of Femoral Neck Fractures?
Performing surgery on a fractured neck of the femur (FNF), or a broken hip, requires a team of healthcare professionals. This team usually includes a main surgeon and their assistant, both of whom have been trained for these complex operations. An anesthetist, who is responsible for putting you to sleep and managing your pain during the procedure, also plays a crucial role. There’s also an operating department practitioner, a highly-trained healthcare worker who assists the surgical team.
During the operation, scrub nurses assist by handing the necessary tools to the surgeon and keeping the operating field sterile. The circulating staff help ‘behind the scenes’, ensuring everything in the operating room runs smoothly, such as getting additional equipment or supplies.
Additionally, during certain types of hip surgeries, such as a sliding hip screw (SHS) or cannulated screw fixation, a radiographer (or X-ray technician) needs to be present. They help to produce real-time X-ray images during the surgery, making sure the screws and other devices are correctly placed.
Preparing for Surgical Management of Femoral Neck Fractures
Before hip surgery, there are some necessary steps doctors take to ensure the best possible outcome. Firstly, a full medical history is collected and a thorough physical check-up is carried out. Doctors also carry out hip and pelvis X-rays from different angles, and a number of standard lab tests, including blood tests to understand the patient’s overall health. In some cases, a chest X-ray and a test of your heart’s electrical activity, an electrocardiogram (ECG), might also be needed. The anesthesiologist, a doctor specialized in giving anesthesia, will also review these results to decide the best type of anesthesia for the patient – either spinal or general. Additionally, patients may need consultation with other specialists, such as internal medicine or cardiology, depending on the presence of other health conditions.
Extra care is taken with patients who have other health conditions and are on specific medications, for instance, blood thinners. For such patients, doctors might need to administer vitamin K or fresh frozen plasma to counteract the effects of these medications. The available reversal agents can vary based on your location.
Before the surgery, patients sign consent forms and their identity is double-checked. In the operation area, a safety checklist from the World Health Organization is completed. The patient’s body is then positioned, cleaned, and covered properly. It’s key to perform and finish the surgery quickly for the best results.
There are various ways to position a patient for hip surgery, and it depends on the exact type of surgery being done. For a “Sliding Hip Screw” or “Cannulated Screw Fixation”, patients lie flat on their backs on a special table. If the operated leg is put in a boot-like device and the other leg is carefully positioned out of the way. It’s important that the hip and leg are positioned just right with the help of X-ray imaging to make sure the surgery goes well.
During a “Hemiarthroplasty” or “Total Hip Arthroplasty” surgery, patients are laid on their side with supportive gear. The hip is positioned at a right angle to the table. The doctor reviews the earlier X-rays to estimate the size of the patient’s hip joint and aims to make the new hip joint match as closely as possible to the original size.
How is Surgical Management of Femoral Neck Fractures performed
There are a few procedures written here – a sliding hip screw operation, a cannulated screw fixation, and a hemiarthroplasty. These are all surgeries performed for various conditions affecting the hip joint, but each is different in method and purpose. Let’s break them down one by one in simpler terms.
In a Sliding Hip Screw procedure, the surgeon begins by making an incision along the side of the thigh. They then gently separate the layers of tissue and muscle to reveal the bone of the femur. They meticulously clean the bone’s surface to provide a clear surface for a specially designed plate. The surgeon then inserts a guidewire through the femur, up into the hip joint. This provides a pathway for the installation of a sturdy metal screw. To ensure the screw fits accurately, measurements are taken multiple times. This screw plays a critical role, as it will help stabilize the femur, letting it heal properly. At last, the screw is linked to a metal plate, which is then secured to the femur with additional screws. The incision is then closed, and the procedure has completed.
The second method, Cannulated Screw Fixation, is used mainly for fractures that haven’t shifted out of place. A minimally sized incision is made at the side of the hip, and three thin guides called guidewires are introduced into the hip. Instead of a solitary but large screw like in a Sliding Hip Screw procedure, three smaller screws are inserted, directed by these guidewires. These screws stabilize the fracture and are usually arranged in the shape of an upside-down triangle. Once the screws are placed correctly, the guidewires are removed, the wound is cleaned and then closed.
The third method, Hemiarthroplasty, involves replacement of the hip joint, typically used for severe fractures. An incision over the hip area is made first. Surgeons then gradually dissect the layers of skin, fat, and muscle until they reach the hip joint. The hip joint is then dislocated, and the broken part of the hip, known as the femoral head, is removed. Then a synthetic joint, also known as a prosthesis, is inserted into the hip socket and fixed to the femur to replace the removed natural hip joint. After ensuring everything is in the correct place, the incision is then closed.
Remember, the exact surgical method used will depend on the specific condition of each patient and the surgeon’s professional judgment.
Possible Complications of Surgical Management of Femoral Neck Fractures
Patients who need an FNF (femoral neck fracture) procedure often have other health problems. These could increase the risk of other complications after the surgery. It’s important to understand these possible challenges to make informed decisions regarding the treatment plan. Here are some possible complications from the surgery:
* Infection: Sepsis (a serious infection) can occur in up to 20% of cases resulting from either a minor or deep infection. Doctors believe having a hematoma (a solid swelling of clotted blood within the tissues) can increase this risk. However, taking antibiotics at the start of the procedure, followed by two doses afterwards, can help lower this risk.
* Fixation failure: This issue is more likely to occur in patients with bone conditions, like rheumatoid arthritis and osteoporosis. It may also happen because of mistakes during the surgery. In addition, loosening or dislocation can occur after a semi-artificial hip replacement (hemiarthroplasty).
* Fracture: There is a 4.5% risk of fracture during hip replacement procedures. These fractures often occur during hip reduction and commonly involve the neck or top of the thigh bone.
* DVT (deep vein thrombosis) and VTE (venous thromboembolism): These issues are a big concern following FNF procedures due to factors such as lack of movement, surgery-related trauma, and underlying health problems. Measures to reduce clotting, such as medications and physical interventions, can help reduce these risks.
* Fat embolism: This is a possible complication from pressurized cemented stems and nailing procedures, which can cause a lack of oxygen. Proper cleaning and drying of the femoral canal can minimize this risk.
* Leg length discrepancy: This issue can happen in any FNF procedure. Small differences can be managed with a shoe lift if they cause problems.
* Nonunion: Nonunion is a condition where the broken bone doesn’t heal properly, causing pain. It’s believed to occur in up to 25% of displaced fractures and 5% of undisplaced fractures. Approach to treatment could range from a total hip replacement in older people to an operation that reshapes the thighbone in young people.
* Dislocation: This complication is often associated with semi-artificial hip replacement (hemiarthroplasty).
* AVN (avascular necrosis): AVN, a condition caused by the death of bone tissue due to lack of blood supply, can happen in up to 10% of undisplaced fractures and 30% to 45% of displaced fractures. This condition is generally treated with a complete hip replacement.
* Malunion: This complication, where a bone heals incorrectly following a fracture, has an incidence of 5% to 30%.
* Death: There’s approximately 30% mortality in the elderly in the first year after undergoing an FNF.
Preventing or effectively managing these surgical complications involves a combination of thorough preoperative preparations, careful surgical technique, and proactive care after the operation. A team-based approach to healthcare, educating patients, and following evidence-based guidelines can help decrease complications and improve patient outcomes.
What Else Should I Know About Surgical Management of Femoral Neck Fractures?
Surgery is a common treatment for serious fractures, but doctors may need to tailor their methods to match the type and condition of the break, as well as the patient’s personal needs. There are some disagreements in the medical community regarding certain surgical techniques, some of which are outlined below.
One key point of debate is the choice between bipolar or unipolar implants, which are used during hip replacement surgeries. Bipolar implants have a movable femoral head within a shell, while unipolar implants are simpler and cheaper. Bipolar implants might offer less pain, less wear on the hip socket, and lower chances of dislocation, making them worth the higher cost. Also, they’re easier to upgrade to a total hip replacement if needed. However, some people believe that bipolar implants lose their internal mobility over time, behaving more like unipolar implants.
Another debated area is the use of cemented versus non-cemented implants. Cemented implants enhance movement and offer better stability than non-cemented types, and surveys suggest that they last longer. However, they also carry a higher risk of fat embolism, a condition which can reduce blood oxygen levels. Non-cemented implants, on the other hand, come with a higher risk of fracture around the implant during and after surgery. Non-cemented implants gain stability by impacting the spongy part of the bone, but poor bone quality can cause instability.
Doctors must also carefully position lag screws, commonly used in fracture treatments. The tip-to-apex distance (distance between the screw tip and the peak of the femur) should be less than 25 mm to reduce the risk of failure. The screw’s placement has to be precise, because if it’s off-center, it could cause the bone and screw to rotate against each other.
Some studies suggest that performing hip replacement surgery early on reduces risks of blood clots, need for blood transfusion or readmission to hospital. Obesity does not seem to increase postoperative complications, but it does lengthen surgery time and exposure to anesthesia. The long-term effect of prolonged anesthesia in obese patients needs further exploration.