Overview of Surgical Management of Femoral Neck Fractures
A femoral neck fracture (FNF) is a break that happens in the femoral neck, which is the area connecting the top part of your thigh bone (femur) to the ball-like part of your hip. These types of breaks can have various effects, both on the physical structure of the bone and the overall health and daily life of the person. They’re more common in older populations, and can pose a significant threat to their independence and well-being, as well as coming with an elevated risk of death in the first year after the break (around 36%). What’s more, the medical costs associated with treating these fractures places a heavy burden on healthcare systems and society as a whole.
There are two main types of FNFs. One type is usually seen in older adults and is caused by low-impact injuries, while the other type is caused by high-force trauma, usually to younger people. That being said, the majority of FNFs happen in older populations. These fractures are even more likely if you have thinning of the bones (osteoporosis), are a woman, have a history of chronic smoking, or have a low body weight. Understanding the various ways of surgically treating FNFs and which patients are best suited for each option is really important for helping people recover in the best way possible.
Anatomy and Physiology of Surgical Management of Femoral Neck Fractures
The hip joint is similar to a ball-and-socket and is made up by the top-part of the thigh bone, or the femur, fitting into a part of the hip bone, known as the pelvic acetabulum. This design allows us to move our legs in various directions like bending, stretching, spreading outwards and inwards, as well as turning. The femoral neck is an essential part of the thigh bone that connects its top-part to the main body of the bone. This region is particularly susceptible to breaking, especially in elderly people who may have a condition called osteoporosis, which weakens the bones.
Around half of all hip fractures are classified as intracapsular fractures, which are mainly seen in older people with osteoporosis. These fractures are different from extracapsular hip fractures based on where they occur. Intracapsular fractures are difficult to heal because they lack an important layer of tissue called periosteum, which feeds the bone, and instead rely on synovial fluid present inside the joint for nourishment. This fluid does not have enough nutrients hence the healing can be problematic.
The hip joint’s blood supply comes from three main sources. The first and most significant source is from the profunda femoris artery, which branches out to certain parts of the hip. The arterial supply comes from other smaller contributors and is predominant in children but less so in adults. If a fracture occurs, the blood flow could be hindered, leading to a condition called avascular necrosis (AVN) which is the death of bone tissue due to a lack of blood supply.
Nerves from the thigh, pelvis, and back regions provide sensation to the hip joint and allow the surrounding muscles to move.
When an older person has a severe intracapsular fracture, doctors typically manage it through surgeries that reconstruct the hip. Common procedures include replacing the top-part of the thigh bone with a prosthesis, either partially or completely. If the fractures are not displaced, screws may be used to secure them. On the other hand, extracapsular fractures, which do not usually hinder the blood flow of the thigh bone, can be treated with a wider variety of surgical techniques. The risk of developing AVN after such fractures is very rare.
Why do People Need Surgical Management of Femoral Neck Fractures
Femoral neck fractures (FNFs), which are breaks in the upper part of your thigh bone near the hip, typically require surgery. Especially in older individuals who may have other health conditions, it’s important to have a team of health professionals working together to manage this type of fracture. The goals of such a surgery include alleviating pain, helping regain movement, and allowing the bone to heal.
Choosing not to have surgery for a FNF is not common and usually only an option for patients who can’t move around and have serious health problems. The main focus instead becomes managing pain and helping the patient move around gradually. However, not having surgery can lead to complications like lung problems, pneumonia, urinary tract infections, pressure sores, and blood clots due to being immobilized.
Because FNFs can cause complications like cutting off the blood supply (AVN) or failing to join back together (nonunion), surgery is often needed to align the broken pieces of bone, stabilize the fracture, and promote healing.
The type of surgery for a FNF could include a hemiarthroplasty (replacing the femoral head), total hip arthroplasty (THA – replacing the entire hip joint), or implanting screws. Hemiarthroplasty is often recommended for fractures within the hip joint, and especially for older patients who are not very active. THA is generally chosen for patients who can move around and have hip pain or arthritis. Techniques and devices for these surgeries have improved, even though there’s a higher risk of hip dislocation.
A Girdlestone resection arthroplasty (removing part of the hip joint) has been used for patients unsuited for hemiarthroplasty perhaps due to widespread infections or severe neurological problems. Yet, a study showed better survival rates and physical functions in patients who had a hemiarthroplasty compared to this procedure.
In older patients with fractures inside the hip joint, or younger people with excellent bone health, cannulated screw fixation (inserting screws into the bone to hold a fracture together) is a suitable option. Technicians usually insert 3 or 4 screws, with no significant difference in results. Still, using two screws is generally seen as less beneficial. In Sweden, a study of patients aged 75 years or older found that the number of patients needing a second operation 1 year after suffering an idle FNF was the same whether they received internal fixation or arthroplasty.
Sliding hip screw fixation (attaching a large screw from the upper thigh bone across the break down to the center of the hip joint) may be used for stable hip fractures and vertical FNFs. This approach allows the fracture to compress, promoting healing as the patient walks after the operation.
When a Person Should Avoid Surgical Management of Femoral Neck Fractures
A specific type of hip fracture repair, known as the sliding hip screw fixation, may not be suitable for some types of hip fractures. This is usually because these conditions make the hip unstable, which could potentially lead to complications. Here are some types of hip fractures that may not be suitable for the sliding hip screw fixation:
- Reverse obliquity: This is a type of fracture where the break in the bone slants in the opposite direction than usual.
- Transtrochanteric involvement: This means that the fracture has extended towards a part of the hip bone known as the trochanter.
- Comminuted fracture patterns with a large posteromedial fragment: In this type of fracture, the bone is broken into many pieces, and a large piece has ended up at the rear and inner side of the hip. This pattern is a problem because an important support structure in the hip, known as the medial calcar buttress, is missing.
- Fracture patterns with subtrochanteric extension: This is where the fracture has extended into a region just below the trochanter.
Meanwhile, Hemiarthroplasty and Total Hip Arthroplasty (THA) – two types of hip replacement surgery – should not be carried out in patients who currently have a hip infection. The infection could potentially spread and cause complications during and after surgery.
Equipment used for Surgical Management of Femoral Neck Fractures
When a person needs a surgical procedure on the neck of the femur (the top part of the thigh bone that connects to the hip), they would undergo the operation in an operating room with special air flow to reduce the risk of infection — this is known as a laminar flow. Doctors use a universal set of surgical tools for such procedures. Additionally, to treat certain types of hip fractures, they would need certain implants, a special surgery table that either allows for skeletal traction (pulling the bone segments back into position) or permits complete access to the body, and a machine capable of producing images in real-time (an image intensifier).
For other kinds of surgeries, like a part of hip replacement (hemiarthroplasty) or total hip replacement (THA), a regular operating table can be used if it supports the patient’s body on the side. Doctors also need a set of implants to replace the joint, as well as additional tools and materials when cement fixation is needed (this means using a special kind of cement to secure the new joint).
In newer practices, THA procedures might use computer-supported navigation and robot assistance to increase accuracy and improve results. Note that the particular requirements will depend on the precise nature of the surgery being performed.
Who is needed to perform Surgical Management of Femoral Neck Fractures?
There are several important medical professionals that are involved when you have FNF, or Fractured Neck of Femur, surgery. The main doctor, or surgeon, and their assistant are in charge of the operation; they’re experts in treating this sort of bone break. An anesthetist is also part of the team, and this is the person who will make sure you stay asleep and don’t feel any pain during the surgery.
Additionally, operating department practitioners and scrub nurses are there to help the surgeon and to make sure that everything remains clean and sterile. Circulating staff are also part of the team, moving around the room to provide whatever is needed.
If you’re having a SHS (Sliding Hip Screw) or a cannulated screw fixation, which are specific types of treatments for this kind of fracture, there will also be a radiographer present. This is a professional who operates the X-ray machine to help guide the procedure. They make sure that everything is in the right place.
Preparing for Surgical Management of Femoral Neck Fractures
Before a surgical procedure on the hip, there are several important steps to follow. First, a doctor will collect all necessary health details about the patient and conduct a physical examination. Doctors also use special X-rays of the hip and pelvis areas to better understand the steps they need to take during the procedure. The patient’s general health will also be assessed through laboratory tests, including a blood count and check of the body’s basic functions like kidney function. The patient’s blood type is also confirmed and matched to ensure compatibility if a blood transfusion is needed. Other standard tests before surgery include a chest x-ray and a heart rhythm test (or ECG).
The anesthesiologist, a doctor who specializes in controlling pain during surgery, will review all this information to decide the best type of anesthesia (medicine to stop pain) for the patient, which can be either general (where the patient is unconscious) or spinal (where the patient is awake but numb from the waist down). If the patient has existing medical conditions, the healthcare team may engage other specialists to ensure the patient is safe to proceed with the surgery.
Patients who are taking blood-thinning medications may need to reverse their effects with Vitamin K or other specific treatments. The options available for this can vary depending on where the patient is located.
Before the surgery, the patient will sign consent forms to confirm they agree to the procedure. In the operating room, a safety checklist from the World Health Organization will be completed to ensure all necessary steps have been taken. The patient will then be positioned for the surgery and the surgical area will be thoroughly cleaned and covered with sterile drapes. To ensure better healing, it is important that the surgery is completed promptly.
The exact position for the patient will depend on the type of surgery. For surgeries involving screws in the hip, the patient is usually placed on their back. The affected leg is braced and the unaffected leg is carefully positioned to allow for X-ray imaging. Gentle movements will be made to properly align the hip which the surgeon will then confirm using an X-ray. If the hip cannot be properly aligned using this technique, an additional procedure may be needed.
For a hip replacement surgery, the patient is usually placed on their side with supports at specific points for comfort and safety. The surgeon will refer to the initial X-rays taken to ensure the artificial hip joint’s size and position match the patient’s natural joint as closely as possible.
How is Surgical Management of Femoral Neck Fractures performed
A sliding hip screw operation involves making an incision on the side of your thigh, around the area below your hip bone. This cut goes through several layers of body tissue such as the skin, fat, and muscle, until it reaches your thigh bone, or femur.
The surgeon then cleans off the muscle around the bone, creating a clear area for the placement of a metal plate. A guiding wire is then placed along your femur, which will serve as a guide for inserting the metal plate and screws. This guiding wire is inserted with care to ensure it is properly aligned with your femur. Using a device that can enhance imaging, the surgeon is able to continually check the position of the wire.
The wire guide is then used to create a channel in your bone for a lag screw (a screw for fastening wood together, but in this case, it is used for bone.). Following that, the metal plate is slid over the lag screw, and the guide wire is removed. Additional screws are inserted onto your femur through the metal plate. Once the procedure is completed, the surgeon takes an x-ray to make sure everything is in place, then the incision is closed and cleaned.
Cannulated screw fixation is another type of surgery, where small screws are used to secure the bone. For this surgery, the surgeon makes a smaller incision than in the previous surgery, also on the side of your thigh. The surgeon then places three guiding wires in an upside-down triangle formation in your thigh bone and inserts screws over these wires.
In a hemiarthroplasty, the surgeon makes a larger incision on the outer part of your hip. The surgeon then peels back layers of muscles and tissues until the hip joint is exposed. The upper portion of your thigh bone, the femoral head, is then cut and removed, and a prosthesis (an artificial body part) is placed in the hip joint. This is often done for hip fractures when the blood supply to the femoral head is damaged.
All three operations aim to fix fractures or other problems in your hip or thigh area. Your doctor will explain the right approach for you based on your specific condition.
Possible Complications of Surgical Management of Femoral Neck Fractures
When a patient has to undergo a Femoral Neck Fracture (FNF) procedure, they often have other health conditions that can increase the chances of complications occurring. Understanding these potential risks can help patients make informed decisions about their treatment options. Let’s look at some possible complications that may arise:
* Infection: There’s a chance of developing sepsis, a serious infection, in up to 20% of cases due to either a skin or deep infection. Health professionals think that the risk of infection increases if there is a hematoma, or blood clot. Antibiotics are typically given at the beginning of the procedure and two more doses are given after surgery.
* Fixation failure: This complication often happens in patients with conditions that affect the bones, like rheumatoid arthritis and osteoporosis. A fixation failure could also be due to surgical errors. The area of placement could also become loose or displace after a half-joint replacement procedure.
* Fracture: The procedure itself brings about a 4.5% chance of fracture, typically around the neck area or the large projection on the hip bone.
* Deep Vein Thrombosis (DVT) and Venous Thromboembolism (VTE): These are serious concerns following FNF procedures due to factors such as not being able to move, surgical trauma, and underlying health conditions. It’s critical to take preventative steps, including medication to prevent clotting and mechanical interventions, to reduce the chance of developing DVT and its possible consequences.
* Fat embolism: This can potentially occur with the pressure from cemented stems and nailing. Lack of oxygen may occur during pressurization or after hip reduction. Thoroughly cleaning and drying the femoral canal can help to reduce the risk.
* Leg length discrepancy: Following an FNF procedure, there might be a slight difference in leg length. This can be managed by using a shoe lift if found problematic.
* Nonunion: This happens when a fracture does not heal, which can cause pain around the hip area that worsens during hip extension or weight-bearing. It’s more common after certain types of hip fracture surgical techniques.
* Dislocation: Certain patients may experience this more often, commonly seen with partial joint replacements.
* Aseptic Necrosis (AVN): This is a condition where the bone tissue dies due to lack of blood supply, and it can occur in a considerable number of fractures. Most patients present with groin pain and signs of the condition may show on radiographs. Management typically includes hip replacements, but alternatives may be considered in younger patients.
* Malunion: This is when the fracture heals in an incorrect anatomical position, which can lead to issues.
* Death: The risk of death is approximately 30% in elderly patients within the first year following an FNF.
Many of these surgical complications can be managed or even prevented by carefully preparing before surgery, using careful surgical techniques, and closely monitoring patients after surgery. Collaboration between healthcare teams, educating patients, and following protocols based on medical research can help lessen the risk of complications and improve patient outcomes.
What Else Should I Know About Surgical Management of Femoral Neck Fractures?
When it comes to mending broken bones, doctors often have to use certain strategies or techniques. These often depend on the type of fracture and the specific needs of the patient. Some of these surgical techniques are debated in the medical community, but they all aim to ensure the best possible healing outcomes.
There are two types of implants doctors use in surgeries called hemiarthroplasty (half hip replacement): Bipolar and Unipolar. Bipolar implants are designed to move within a protective case on the hip joint. They are generally more expensive and a bit more complicated but can lead to less pain and fewer complications. On the other hand, unipolar implants are simpler and cheaper, but over time, they can lose some of their mobility and start acting like unipolar implants.
Another point of discussion is whether to use cemented or uncemented implants. Cemented ones are often better because they let patients move easily and are more stable. However, they carry an increased risk of fat entering the bloodstream (fat embolism) which affects oxygen supply to the body. Research shows that more cemented stems survive longer than uncemented ones. The cement acts like a glue, helping distribute the pressures between the implant and the bone. Uncemented implants have a higher risk of fractures around the implant, both during and after the surgery. While they rely on the fit into the bone for stability, poor bone quality can decrease stability.
When using a particular screw (SHS Lag Screw) method, the placement is crucial. The location of the screw tip relative to the peak of the femoral head (TAD) should be less than 20 mm in order to avoid complications. The lag screw should be slightly lower on the front to back view and slightly to the back on the side view. The upper front region is where the bone quality is the weakest.
Also, getting a Total Hip Arthroplasty (THA) or half hip replacement surgery done early after the injury is found to lower the risk of blood clots in the lungs, deep vein thrombosis, and the need for blood transfusions, among other things.
As for obese patients, although obesity was found to increase surgery time, it did not increase the risk of complications after the surgery. However, longer anesthesia exposure in these patients needs further study.
