Should I take or not take the internal fixation after a fracture? This is the question

Author: Lin Jian: Deputy Chief Physician, First People's Hospital, Shanghai Jiao Tong University School of Medicine

Reviewer: Lin Haodong, Professor and Chief Physician, First People's Hospital, Shanghai Jiaotong University School of Medicine

Last year, 30-year-old Xiao Wang accidentally fell while skiing and was diagnosed with an "ankle fracture" by the doctor, so he underwent open reduction and internal fixation surgery. During the follow-up examination, the doctor told Xiao Wang that the fractured part had healed smoothly and recovered well. Upon hearing this good news, Xiao Wang was happy but also entangled: During the operation, an internal fixation was placed in the ankle. Does it need another operation to remove the fixation material? If it is not removed, will there be any impact?

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The problem that Xiao Wang is struggling with is very representative.

Open reduction and internal fixation is a surgical procedure that exposes the fractured ends after cutting the skin and subcutaneous tissue, and uses internal fixation devices at the fracture site to help the bones reset and maintain their position. However, after the fracture heals, whether the internal fixation device needs to be removed and when it should be removed are very important issues.

Here we will not discuss special situations such as infection, displacement, and failure of internal fixation. When the fracture treatment is successful, whether the internal fixation device should be removed needs to be analyzed based on the patient's personal situation, taking into account various factors such as the location of the fracture, the retention time of the internal fixation device, and the patient's physical condition.

1. Consider the location of the fracture

Different parts of the human body not only have different functions, but more importantly, the mechanical environments of different parts are completely different. For example, the upper limbs are mainly required to be flexible, and the range of joint motion is large; the lower limbs are required to bear weight, and they need to withstand gravity to maintain stability. Therefore, the fracture site is the primary issue to consider whether to remove the internal fixator. In addition, the anatomical structure of different parts is different, and the surgical risks of removing the internal fixator are also different. This also affects the doctor's decision on whether to remove the internal fixator.

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1. Thighs and calves

The main bones in the thigh and calf are the femur and tibia. These bones are relatively strong, surrounded by thick soft tissue, and have abundant blood supply. When a fracture occurs in the thigh or calf, minimally invasive surgery such as intramedullary nailing is often used for internal fixation. The surgical trauma is relatively small, so the internal fixation device can be removed after the fracture heals.

2. Ankle

The main bones of the foot and ankle include the medial malleolus, lateral malleolus, calcaneus, talus, cuneiform bones, metatarsals, and phalanges. These bones are relatively superficial, and some patients may experience discomfort due to irritation of the soft tissue by the internal fixators, so they want to remove them. However, the posterior malleolus and talus are special. The bones in these two parts are relatively deep, and if the internal fixators are removed again after the fracture heals, new injuries may occur, resulting in scar adhesions, which may lead to a decline in joint function compared to before the internal fixators were removed.

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3. Upper arms and shoulders

The main bone of the upper arm is the humerus. The anatomical structure of the humerus is very special, especially the radial nerve runs closely along the middle and lower 1/3 of the humerus. When removing internal fixation devices, it is very difficult for doctors to ensure the safety of the radial nerve during surgery due to scar hyperplasia and soft tissue adhesion caused by the initial surgery (fracture). Therefore, it is not recommended to perform a second surgery to remove internal fixation devices after humeral fracture.

The superficial bone of the shoulder is the clavicle, and it is easy to remove the internal fixation device at this site, but the quality of fracture healing must be evaluated because the probability of refracture of the clavicle is relatively high. However, the scapula is located very deep, and the internal fixation process causes greater damage. Therefore, it is not recommended to remove the internal fixation device after scapula fracture surgery.

4. Forearm and wrist

The main bones of the forearm are the ulna and radius, which are relatively superficial, so it is not difficult to remove the internal fixation. However, like the clavicle, they have a high probability of refracture, so whether to remove the internal fixation requires evaluating the quality of fracture healing.

If steel needles are used for internal fixation of the hand, it is very convenient to remove the needles later and they should generally be removed in time. If steel plates are used for internal fixation of the hand, the subsequent removal needs to consider the recovery of finger and wrist function. Sometimes it is necessary to release the adhesion of the tendon while removing the internal fixator to improve the function of the wrist.

5. Spine and pelvis

The spine contains multiple movable intervertebral joints. If internal fixation is used for vertebral fractures, it is generally necessary to remove the internal fixation after the fracture heals to restore the mobility of the spine. If fusion internal fixation is used for vertebral fractures, the internal fixation may not be removed afterwards because the treatment strategy has given up the range of motion of this part of the joint.

The location of the internal fixation device in the pelvis is generally quite deep, and there are many important nerves and blood vessels around it, so it is recommended not to remove the internal fixation device.

2. Consider the retention time of internal fixation

The greatest progress of internal fixation materials is that their tissue compatibility is becoming more and more ideal, and their biomechanical properties are becoming closer and closer to normal bones. Internal fixation devices exist in the body and will inevitably interact with bones and surrounding soft tissues. The different retention time of internal fixation devices will also affect the decision of whether to remove the internal fixation devices.

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For fixation methods that aim to limit joint movement, such as using a clavicle hook to limit the acromioclavicular joint and a syndesmotic screw to limit the syndesmotic joint, they are generally removed as soon as the soft tissue around the joint has stabilized. The clavicle hook is generally removed 6 months after open reduction and internal fixation, and the syndesmotic screw is generally removed 2 to 3 months after surgery.

For fixation methods that aim to maintain fracture reduction, internal fixation devices are generally considered for removal after the fracture has healed and bone remodeling is complete. The ideal time window is about 1 year after surgery. When the internal fixation device is retained for too long, such as more than 2 years or even 5 years, the binding state of the internal fixation device and the bone will become unpredictable. It is possible that during surgery, it will be found that the callus completely wraps the internal fixation device, or that the internal fixation device is too tightly bound to the bone, greatly exceeding the torque generated when the screwdriver is removed, and even in extreme cases, the screwdriver may be twisted off. These situations will greatly increase the difficulty of the internal fixation removal surgery, and may even make it impossible to remove.

3. Consider the patient’s physical condition

For a long time, some patients have mistakenly believed that the surgery to remove internal fixators is a minor surgery that does not need to be taken seriously. In fact, although this surgery was not performed to treat fractures, the risks from anesthesia to surgical incision and exposure of the surgical site are no less than the first fracture surgery. What's more, this surgery may also cause accidents such as severe soft tissue adhesion, unsuccessful separation of nerves and blood vessels, slippage of the tail of the internal fixator, and fracture of the internal fixator. Therefore, we cannot take the surgery to remove internal fixators lightly. For those patients who are elderly, in poor physical condition, and cannot tolerate long-term anesthesia, it is better to leave the internal fixator in the body.

In short, whether the internal fixation device needs to be removed is a complex issue. With the development of internal fixation materials, their compatibility with human tissues is getting better and better, and the situation where the internal fixation device must be removed is becoming less and less. If the patient really wants to remove the internal fixation device, then we should analyze the patient's situation in detail and adopt a personalized plan. Therefore, if you encounter the above problems, it is recommended that you work closely with your doctor to carefully analyze the location of the internal fixation device, the retention time, your own physical condition, etc., and jointly decide whether to remove the internal fixation device to obtain the best treatment effect.