Fracture

March

Definition

A fracture refers to an interruption in the integrity and continuity of a bone.

Causes

Fractures can result from trauma or bone diseases. For cases involving bone diseases such as osteomyelitis or bone tumors, bone destruction occurs, and fractures may happen under minimal external force; these are classified as pathological fractures. Traumatic fractures are more common clinically.

Direct Trauma

Direct force applied to the injured site results in a fracture, often accompanied by varying degrees of soft tissue injury.

Figure 1 Tibiofibular shaft fracture in the lower leg caused by direct trauma

Indirect Trauma

Force is transmitted through mechanisms such as conduction, leverage, rotation, and muscle contraction, leading to a fracture at a distal site due to the relationship between applied force and reactive force. For example, falling and landing on the palm can cause distal radius fractures as force travels upward along the arm depending on the angle between the upper limb and the ground. Sudden kneeling may cause a strong contraction of the quadriceps muscle, resulting in a patellar fracture.

Figure 2 Distal radius fracture caused by indirect trauma

Figure 3 Patellar fracture caused by indirect trauma

Fatigue Fracture (Stress Fracture)

Prolonged, repetitive, and minor direct or indirect injuries can lead to fractures at specific locations on a limb. For instance, long-distance marches may cause fractures of the second or third metatarsals, which are referred to as fatigue fractures or stress fractures.

Classification

Classification Based on the Integrity of the Skin or Mucosa at the Fracture Site

Closed Fracture

The skin or mucosa over the fracture remains intact, and the fractured bone does not communicate with the external environment.

Open Fracture

A fracture where the skin or mucous membrane at the fracture site is ruptured, allowing the broken bone ends to communicate with the external environment. The wound at the fracture site may result from external injuries such as knife or gunshot wounds penetrating inward, or from the fractured bone end piercing the skin or mucous membrane outward from within. Examples include pubic fractures accompanied by bladder or urethral rupture, and coccyx fractures resulting in rectal rupture, both of which are classified as open fractures.

Figure 4 Schematic diagram of an open fracture
1，Pubic fracture accompanied by posterior urethral rupture.
2，Coccygeal fracture leading to rectal rupture.

Classification Based on the Nature and Shape of the Fracture

Figure 5 Schematic classification of humeral fractures
(1) Transverse fracture; (2) Oblique fracture; (3) Spiral fracture; (4) Comminuted fracture; (5) T-shaped fracture.

Classification is made based on the direction and shape of the fracture line:

Transverse Fracture: The fracture line is nearly perpendicular to the longitudinal axis of the bone.
Oblique Fracture: The fracture line forms a certain angle with the bone's longitudinal axis.
Spiral Fracture: The fracture line takes on a spiral shape.
Comminuted Fracture: The bone is broken into three or more fragments.
Greenstick Fracture: Common in children and occurs in long bones. When subjected to external force, the diaphysis bends without obvious breaks or displacement.
Impacted Fracture: Fragments of the fractured bone are driven into each other. This is commonly seen in femoral neck fractures, where the compact bone of the shaft is driven into the cancellous bone of the neck.
Compression Fracture: Cancellous bone becomes deformed due to external compressive forces, often affecting vertebral bodies.
Epiphyseal Injury: The fracture line involves the epiphysis and may include varying amounts of bone tissue. This type of injury is classified into five types by Salter and Harris.

Figure 6 Impacted femoral neck fracture (complete fracture)

Figure 7 Vertebral compression fracture

Figure 8 Different types of epiphyseal injuries

Classification Based on the Stability of the Fracture Ends

Stable Fracture

Fracture ends remain in position and are unlikely to displace. Examples include fissure fractures, greenstick fractures, transverse fractures, compression fractures, and impacted fractures.

Unstable Fracture

Fracture ends are prone to displacement. Examples include oblique fractures, spiral fractures, and comminuted fractures.

Displacement of Fracture Ends

Most fractures show varying degrees of displacement. There are five common types:

Angulated Displacement: The longitudinal axes of the fragments intersect, forming angles in anterior, posterior, medial, or lateral directions.
Shortened Displacement: The bone ends overlap or impact, resulting in shortening of the bone.
Rotational Displacement: The distal fracture end rotates around the longitudinal axis of the bone.
Lateral Displacement: The distal fracture end shifts anteriorly, posteriorly, medially, or laterally relative to the proximal end.
Separated Displacement: The fracture ends are separated along the longitudinal axis, forming a gap between them.

Figure 9 Displacement patterns of fracture fragments
(1) Angulated displacement; (2) Lateral displacement; (3) Shortening displacement; (4) Separation displacement; (5) Rotational displacement.

Factors contributing to different types of displacement include:

The direction of external direct force.
Muscle tension acting on different regions of the fracture site.
Improper handling during transportation.

Figure 10 Fracture displacement caused by muscular traction at both ends
(1) Fracture located above the insertion of the pectoralis major muscle;
(2) Fracture located below the insertion of the pectoralis major muscle;
(3) Fracture located below the insertion of the deltoid muscle.

March

Clinical Manifestations

Most fractures mainly result in localized symptoms, while severe fractures and multiple fractures may cause systemic reactions.

Systemic Symptoms

Shock

Bleeding caused by fractures is the primary reason for shock, especially in cases such as pelvic fractures, femoral fractures, and multiple fractures, where the blood loss can exceed 2,000 ml. Severe open fractures or fractures complicated by injuries to vital internal organs can also lead to shock or even death.

Fever

In most cases, body temperature remains normal after a fracture. However, in fractures with significant blood loss, such as femoral fractures and pelvic fractures, low-grade fever may occur during hematoma absorption, typically not exceeding 38°C. In open fractures, high fever may suggest the possibility of infection.

Local Symptoms

General Features of Fractures

Localized pain, swelling, and functional impairment are commonly observed. Bone fractures can cause bleeding due to rupture of bone marrow, periosteum, and surrounding tissue blood vessels, resulting in hematoma formation at the fracture site. Swelling caused by soft tissue injury may lead to severe swelling of the affected limb, occasionally accompanied by tension-type blisters and subcutaneous ecchymosis. Fractures can cause intense pain at the site, which intensifies with limb movement, accompanied by marked tenderness. Swelling or pain often limits the functional movement of the affected limb. In cases of complete fractures, functional activity of the injured limb may be entirely lost.

Specific Features of Fractures

Deformity

Displacement of fracture ends may alter the appearance of the affected limb, often presenting as shortening, angulation, or rotational deformities.

Abnormal Mobility

Abnormal movements may occur at areas of the limb where motion would not normally be possible.

Crepitus or Grinding Sensation

Fractures may produce crepitus or a grinding sensation when the ends of the fractured bones rub against each other.

The presence of any of these three specific fracture features is considered diagnostic evidence for a fracture. However, certain types of fractures, such as fissure fractures, impacted fractures, spinal fractures, and pelvic fractures, may lack these specific features. In such cases, routine X-ray examinations are necessary, with CT or MRI scans performed as needed to confirm the diagnosis.

X-Ray Examination

Routine X-ray examination is typically performed. X-ray imaging is essential even when a clinical presentation strongly suggests a fracture, as it provides critical information about the fracture type and displacement of the fracture ends, which is crucial for guiding treatment.

X-ray imaging involves obtaining anteroposterior and lateral views, including adjacent joints. Special positioning may be required in certain cases. For example, metacarpal and metatarsal bones require anteroposterior and oblique views, calcaneus requires lateral and axial views, scaphoid bone imaging includes anteroposterior and butterfly views, and atlanto-axial vertebra imaging calls for an open-mouth view.

In some cases, small fissure fractures may not show distinct fracture lines on emergency X-rays. A follow-up X-ray at two weeks post-injury is recommended, as fracture lines may become apparent due to absorption at the fracture ends. This is especially relevant for scaphoid fractures and impacted femoral neck fractures.

CT Examination

For fractures in complex anatomical regions or areas where routine X-rays are inadequate, CT scans can offer more diagnostic information. This is particularly useful for fractures involving the pelvis, hip joint, sacrum, sacroiliac joint, sternum, and spine.

Figure 1 CT scan demonstrating vertebral burst fracture with bone fragments protruding into the spinal canal.

MRI Examination

MRI is highly effective at visualizing soft tissue structures, as well as assessing ligament and spinal cord injury around the vertebral column. MRI can also detect intraspinal bleeding and identify occult fractures and the extent of bone contusions that might remain undetected through X-ray and CT examinations.

Figure 2 MRI scan showing L₁ vertebral compression fracture accompanied by spinal cord injury.

March

In certain complex injuries, the fracture itself may not be the primary concern; the associated or resulting damage to critical tissues or organs can have more significant consequences, often triggering severe systemic reactions and, in some cases, posing a life-threatening risk. Complications that arise during fracture management can seriously impact treatment outcomes and require careful prevention and timely, appropriate intervention.

Early Complications

Shock

Shock can result from severe trauma, massive hemorrhage caused by fractures, or damage to vital organs.

Fat Embolism Syndrome (FES)

Fat embolism syndrome typically occurs in adults, especially young and middle-aged individuals with femoral shaft fractures. It is caused by excessive hematoma tension within the medullary cavity and bone marrow destruction, allowing fat droplets to enter ruptured venous sinuses, leading to pulmonary and cerebral fat embolism. Clinically, it manifests as hypoxemia, neurological abnormalities, and petechial rash.

Injuries to Vital Organs

Liver and Spleen Rupture

Severe injuries to the lower chest wall, in addition to causing rib fractures, may also result in rupture and hemorrhage of the spleen on the left side or the liver on the right side, potentially leading to shock.

Lung Injuries

Rib fractures can damage intercostal blood vessels and lung tissue at the fracture site, causing conditions such as pneumothorax, hemothorax, or hemopneumothorax, which may lead to severe respiratory distress.

Bladder and Urethral Injuries

Commonly associated with pelvic fractures, these injuries may cause urine leakage, resulting in pain, swelling, and bruising in the lower abdomen and perineal region, as well as hematuria and difficulty urinating.

Rectal Injuries

Sacrococcygeal fractures can cause rectal injuries, leading to lower abdominal pain and rectal bleeding.

Injuries to Surrounding Tissues

Damage to Major Blood Vessels

This is commonly seen in fractures such as supracondylar fractures of the femur, where the distal fracture end may injure the popliteal artery; proximal tibial fractures, which may harm the anterior or posterior tibial artery; and extension-type supracondylar fractures of the humerus, where the proximal fracture end can easily damage the brachial artery.

Figure 1 Brachial artery injury resulting from extension-type supracondylar fracture of the humerus.

Injury to Surrounding Nerves

Nerve injuries are especially likely in areas where nerves are closely adjacent to bones. For instance, fractures at the junction of the middle and lower thirds of the humerus can easily damage the radial nerve that runs along the radial groove of the humerus.

Spinal Cord Injuries

Spinal fractures and dislocations may lead to serious spinal cord injuries, particularly in the cervical and thoracolumbar regions. Such injuries can result in paralysis below the level of the neurological injury.

Osteofascial Compartment Syndrome (OCS)

Osteofascial compartment syndrome is an acute syndrome characterized by ischemia of muscles and nerves within a compartment formed by bone, interosseous membranes, fascial septa, and deep fascia. It is commonly seen on the palmar side of the forearm or in the lower leg. This condition often arises from hematoma formation and tissue swelling following traumatic fractures, which increase the volume of the compartment’s contents. It may also be caused by excessively tight external bandages or local compression that reduces the compartment volume, leading to increased intracompartmental pressure. When the intracompartmental pressure reaches a critical level, the small arteries supplying the muscles may close, initiating a vicious cycle of ischemia–edema–ischemia. Depending on the degree of ischemia, potential outcomes include:

Impending Ischemic Contracture

In the early stages of ischemia, timely management to restore blood supply can prevent muscle necrosis or result in only minimal necrosis without functional impairment of the limb.

Ischemic Contracture

In cases of short-term or more severe incomplete ischemia, significant muscle necrosis occurs even after blood supply is restored, leading to contracture deformities (e.g., Volkmann’s ischemic contracture), which severely impact limb function.

Gangrene

Prolonged and extensive complete ischemia causes massive muscle necrosis (gangrene), often necessitating amputation. The release of large amounts of toxins into the bloodstream may lead to complications such as shock, arrhythmias, and acute renal failure.

Early diagnosis of osteofascial compartment syndrome can be made based on the following four signs:

Sensory abnormalities in the affected limb.
Pain during passive stretching of the involved muscles (positive passive stretch test).
Pain during active flexion of the muscles.
Tenderness over the muscle belly within the compartment.

Osteofascial compartment syndrome may also lead to complications such as myoglobinuria and hyperkalemia. Treatment requires sufficient fluid resuscitation to promote diuresis. If the compartment pressure exceeds 30 mmHg or the pressure gradient (diastolic pressure minus compartment pressure) falls below 30 mmHg, fasciotomy should be performed promptly to relieve pressure.

Late Complications

Hypostatic Pneumonia

Hypostatic pneumonia primarily occurs in patients who are bedridden for extended periods due to fractures, especially elderly, debilitated individuals or those with chronic illnesses. It can occasionally become life-threatening.

Decubitus Ulcers

Decubitus ulcers may develop in patients with severe traumatic fractures who remain bedridden for extended periods. Prolonged pressure on bony prominences can lead to local blood circulation impairment and ulcer formation. Common sites include the sacrum, hips, and heels. Paraplegic patients, due to the loss of nerve innervation and lack of sensation, are particularly prone to decubitus ulcers. Poor local circulation not only makes these ulcers more likely to occur but also renders them difficult to heal, often becoming a source of systemic infection.

Deep Vein Thrombosis (DVT)

Deep vein thrombosis is commonly observed in cases of pelvic fractures or lower limb fractures. Prolonged immobilization of the lower extremities, combined with trauma-induced hypercoagulable states, can lead to venous thrombosis.

Infection

Infection rates range from 1% to 5%. Factors such as poor local blood supply to the fracture site, impaired soft tissue integrity, incomplete debridement of open fractures, or inadequate soft tissue coverage can contribute to infections, which may progress to suppurative osteomyelitis.

Traumatic Myositis Ossificans

Traumatic myositis ossificans, also known as heterotopic ossification, occurs around joints due to sprains, dislocations, or fractures near a joint. When subperiosteal hematoma forms because of periosteal stripping and is improperly managed, the hematoma may enlarge, undergo organization, and lead to extensive ossification within the soft tissue around the joint. Severe cases result in significant joint movement dysfunction. This condition is most commonly observed around the elbow joint.

Traumatic Arthritis

Traumatic arthritis often results from intra-articular fractures that fail to achieve anatomical reduction. Irregularities in the joint surface after bone healing can cause persistent joint pain during movement due to chronic wear and tear.

Joint Stiffness

Prolonged immobilization of the affected limb can lead to venous and lymphatic drainage issues. Serofibrinous exudation and fibrin deposition within the perijoint tissues may cause fibrous adhesions. Concurrently, contractures of the joint capsule and surrounding muscles can result in restricted joint mobility.

Acute Bone Atrophy (Sudeck's Atrophy)

Acute bone atrophy, also known as reflex sympathetic dystrophy, is characterized by painful osteoporosis and soft tissue atrophy near the joint due to injury. It frequently occurs after fractures of the hands or feet. Typical symptoms include pain and vascular dysregulation. The intensity of the pain is disproportionate to the severity of the injury and worsens with movement of nearby joints. A burning sensation is often present. Muscle spasm around the joint leads to joint stiffness. Vascular dysregulation initially manifests as elevated skin temperature, edema, and accelerated growth of hair and nails. Over time, skin temperature drops, excessive sweating occurs, the skin becomes smooth, and hair loss is noted. Swelling, stiffness, coldness, and a slightly cyanotic appearance of the hand or foot can persist for several months.

Avascular Osteonecrosis

Avascular osteonecrosis can occur when the blood supply to a fracture fragment is disrupted, leading to ischemic necrosis of the affected bone. Common examples include avascular necrosis of the proximal scaphoid following scaphoid fractures and femoral head necrosis after femoral neck fractures.

Figure 2 Avascular necrosis of the femoral head after femoral neck fracture.
(1) Diagram of femoral neck blood supply and fracture.
(2) Secondary femoral head avascular necrosis resulting from femoral neck fracture.

Ischemic Contracture

Ischemic contracture is one of the most severe complications of fractures and represents the serious consequences of inadequately managed osteofascial compartment syndrome. It can be directly caused by fractures and associated soft tissue injuries, but more commonly, improper handling of fractures such as overly tight external fixation contributes to the condition. Recognizing osteofascial compartment syndrome early and managing it appropriately is vital for preventing ischemic contracture. Once it occurs, treatment becomes extremely challenging with poor outcomes, often resulting in significant disability. A typical deformity associated with ischemic contracture is claw hand or claw foot.

Figure 3 Typical deformity of claw hand following ischemic contracture of the forearm.

March

Fracture Healing Process

The process of fracture healing is complex and continuous. From the perspective of histological and cellular changes, it is typically divided into three stages. However, these stages are interwoven and gradually evolve rather than being strictly separate.

Hematoma Organization and Inflammatory Phase

This stage involves the formation of granulation tissue. Fractures lead to the rupture of blood vessels in the marrow cavity, beneath the periosteum, and within the surrounding tissues, resulting in hematoma formation at and around the fracture site. Within 6–8 hours after injury, the hematoma begins to coagulate into a clot due to the activation of both intrinsic and extrinsic coagulation systems. Severe trauma and vascular disruption at the fracture ends can result in ischemia, leading to necrosis of soft tissue and bone and triggering a sterile inflammatory response.

Figure 1 Hematoma organization forming granulation tissue within 2 weeks after fracture

Products released by ischemic and necrotic cells promote local capillary proliferation, vasodilation, plasma exudation, edema, and inflammatory cell infiltration. Neutrophils, lymphocytes, monocytes, and macrophages infiltrate the hematoma and necrotic bone areas, gradually clearing blood clots, necrotic soft tissue, and dead bone, leading to the organization of the hematoma into granulation tissue.

The formation of fibrous connections is typically completed around two weeks post-fracture. Fibroblasts within the granulation tissue synthesize and secrete large amounts of collagen fibers, transforming the granulation tissue into fibrous connective tissue that bridges the two fracture ends, a process known as fibrous connection. Meanwhile, osteoblasts from the periosteum near the fracture end become activated shortly after the injury and begin to proliferate. By the first week, osteoblasts start forming bone-like tissue parallel to the diaphysis, which gradually extends and thickens. Similarly, the endosteum undergoes analogous changes slightly later.

Figure 2 Formation of bone-like tissue in the periosteum and endosteum during weeks 2–6

Primary Callus Formation Phase

This phase typically lasts 3–6 months in adults. During this stage, internal and external calluses begin to form. Proliferation of the periosteum and endosteum occurs, accompanied by the ingrowth of new blood vessels. Osteoblasts proliferate extensively, synthesizing and secreting bone matrix. The bone-like tissue formed near the fracture ends gradually undergoes ossification, forming new bone through intramembranous ossification. The bone formed on the inner and outer surfaces of the cortex by the endosteum and periosteum, respectively, constitutes the internal callus and external callus.

Figure 3 Formation of internal and external calluses during weeks 6–12

The callus continues to calcify and strengthen. Once the callus develops sufficient strength to resist forces from muscle contraction, shear stress, and rotational stress, the fracture is considered clinically healed. At this point, X-ray imaging reveals fusiform callus shadows at the fracture site, although the fracture line may still be faintly visible.

Intramembranous ossification occurs faster than endochondral ossification during fracture healing and is primarily driven by periosteal activity. Therefore, damage to the periosteum negatively impacts fracture healing.

Callus Remodeling and Reshaping Phase

This stage typically takes 1–2 years to complete. During this process, the new trabecular bone in the primary callus gradually thickens and becomes more organized and dense. Necrotic bone at the fracture ends is cleared through the combined activity of osteoclasts and osteoblasts, which replace it with new bone via a process known as creeping substitution. The primary callus is eventually replaced by lamellar bone, resulting in a robust bony union at the fracture site.

Figure 4 Remodeling and reshaping of callus over 1–2 years

Over time, in accordance with Wolff’s law, osteoblastic activity becomes more pronounced along the stress axis, leading to the generation of additional new bone and the formation of strong lamellar bone. Conversely, osteoclastic activity dominates in areas outside the stress axis, resulting in the gradual resorption and removal of excess callus. The medullary cavity is re-established, and the fracture site regains normal bone structure, leaving behind no histological or radiological evidence of the injury.

Clinical Criteria for Fracture Healing

Clinical healing represents a critical stage in the fracture healing process. The criteria for clinical healing include:

Absence of local tenderness or pain upon vertical percussion.
Absence of abnormal mobility at the fracture site.
X-ray imaging indicating the presence of continuous calluses, and the fracture line appearing indistinct.

March

Factors Affecting Fracture Healing

Fracture healing is a complex process influenced by multiple factors. It is important to have a thorough understanding of these factors to utilize and enhance beneficial ones while avoiding and overcoming adverse ones, ultimately facilitating fracture healing.

Systemic Factors

Age

Fracture healing varies significantly with age. For example, femoral fractures in newborns can achieve strong union as early as two weeks, while in adults, it typically takes around three months. Fractures in children heal relatively quickly, whereas healing in elderly individuals requires a longer time.

Health Condition

Poor health conditions, particularly in patients with chronic wasting diseases such as diabetes, malnutrition, malignancies, or disorders of calcium and phosphorus metabolism, significantly prolong fracture healing time.

Local Factors

Type of Fracture

Spiral and oblique fractures, due to their larger fracture surface area, heal faster. Transverse fractures, with smaller contact areas, heal more slowly. Multiple fractures or comminuted fractures involving multiple segments of a bone also require more time for healing.

Blood Supply at the Fracture Site

Blood supply to the fracture site is a critical factor affecting fracture healing. Different fracture locations have varying levels of blood supply at the fracture ends. A complete loss of blood supply to the fracture ends significantly increases the likelihood of nonunion. For instance, subcapital femoral neck fractures often disrupt the blood supply to the femoral head almost entirely, leading to a higher risk of nonunion or avascular necrosis.

Severity of Soft Tissue Injury

Severe soft tissue injury, particularly in open fractures, can directly damage nearby muscles, blood vessels, and the periosteum at the fracture ends, disrupting blood supply and impairing fracture healing.

Interposed Soft Tissue

Interpoxed soft tissue, such as blood vessels, muscles, and tendons, between the fracture ends, can obstruct their alignment and contact, making fracture healing difficult or even leading to nonunion.

Figure 1 Interposed soft tissue between the fracture ends

Infection

Local infections can result in suppurative osteomyelitis, causing soft tissue necrosis and sequestrum formation, which severely impairs fracture healing.

Inadequate Treatment Methods Affecting Fracture Healing

Repeated Manual Reduction

Repeated attempts at manual reduction can damage local soft tissue and the periosteum, adversely affecting fracture healing. While manual reduction preserves fracture site blood supply better, it often struggles to achieve anatomical alignment.

Excessive Tissue Stripping During Open Reduction

Excessive stripping of soft tissue and periosteum during open reduction surgery can impair blood supply to the fracture segments, potentially causing delayed fracture healing or nonunion. Surgical interventions should minimize disruption to the local blood supply.

Over-Removal of Bone Fragments During Debridement of Open Fractures

Excessive removal of bone fragments during debridement of open fractures can lead to bone loss, resulting in nonunion of the fracture.

Excessive Traction Force During Continuous Skeletal Traction

Overly high traction forces during continuous skeletal traction can cause separation of the fracture ends and may induce vascular spasm, leading to insufficient local blood supply and resulting in delayed fracture healing or nonunion.

Inadequate Fracture Stabilization

Unstable fracture fixation can expose the fracture to shear stress and rotational forces, interfering with callus formation and negatively impacting fracture healing.

Premature or Improper Functional Exercises

Initiating functional exercises too early or performing them incorrectly can disrupt fixation at the fracture site, thereby impairing fracture healing. Proper and appropriate functional exercises, performed under medical supervision, promote blood circulation in the limb, reduce swelling, and prevent muscle atrophy, osteoporosis, and joint stiffness. They are beneficial for joint functional recovery.

March

First Aid for Fractures

Fractures, especially severe ones such as pelvic fractures or femoral fractures, are often part of serious systemic multiple injuries. Therefore, first aid at the scene requires not only attention to the fracture itself but also careful consideration of the patient's overall condition.

The goal of fracture first aid is to use the simplest yet most effective methods to save lives, protect the injured limb, and ensure rapid transportation for timely and proper medical treatment.

Managing Shock

The patient's overall condition should be assessed first. If the patient is in a state of shock, measures such as keeping the patient warm and minimizing movement are necessary. If possible, fluid infusion or blood transfusion should be initiated immediately. For patients with comorbid head injuries and in a comatose state, maintaining a clear airway is essential.

Dressing the Wound

In cases of open fractures, most wounds with bleeding can be stopped through pressure dressing. For bleeding from major blood vessels where pressure dressing alone is insufficient, a tourniquet can be applied, and the pressure and application time should be recorded. The wound should be covered with sterile dressings or clean cloths to minimize further contamination.

If the fracture end punctures through the wound and is contaminated but does not compress critical blood vessels or nerves, it should not be repositioned to prevent deeper contamination. Repositioning should only be performed at the hospital following debridement. If the fracture end spontaneously retracts into the wound during dressing, this should be documented for further management during hospital debridement.

Proper Immobilization

Immobilization is a crucial measure in fracture first aid. Any suspected fracture should be treated as such. For closed fractures, there is no need to remove the patient's clothing, shoes, or socks during first aid to avoid excessive movement of the injured limb and exacerbation of pain. If the injured limb is severely swollen, clothing may be carefully cut open with scissors to reduce compression.

In cases where the fracture exhibits significant deformity and poses a risk of soft tissue rupture or damage to nearby major blood vessels or nerves, gentle traction of the affected limb can be applied to stabilize it before immobilization.

The purposes of immobilization include:

Preventing the fracture ends from damaging vital surrounding structures, such as blood vessels, nerves, or internal organs, during transportation.
Reducing mobility of the fracture ends to alleviate the patient's pain.
Facilitating safe and efficient transportation.

Immobilization can be achieved using specially designed splints or improvised materials, such as wooden boards, sticks, or tree branches. If no materials are available, upper limb fractures can be immobilized by securing the injured limb to the chest, while lower limb fractures can be immobilized by binding the injured limb to the uninjured opposite limb. For spinal fractures, lateral or rolling methods of transport should be used.

Prompt Transport

After preliminary treatment and proper immobilization, the patient should be transported as quickly as possible to the nearest hospital for further medical care.

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The treatment of fractures adheres to three primary principles: reduction, fixation, and rehabilitation.

Reduction

Reduction involves restoring the displaced fracture fragments to their normal or near-normal anatomical alignment, re-establishing the structural integrity of the bone.

Fixation

Fixation refers to maintaining the fracture in its reduced position to ensure solid healing under optimal alignment. This step is critical for successful fracture healing.

Functional Exercise and Rehabilitation

Functional exercise and rehabilitation aim to restore the contractile activity of soft tissues such as muscles, tendons, ligaments, and joint capsules in the injured limb as early as possible without compromising fixation. Early and appropriate functional exercise and rehabilitation form the cornerstone of recovering limb function.

Fracture Reduction

Standards for Reduction

Anatomical Reduction

Anatomical reduction is achieved when the fracture fragments are restored to their normal anatomical relationships following reduction. This requires complete correction of alignment (longitudinal axis relationship between fracture fragments) and apposition (contact between fracture ends).

Figure 1 Anatomical reduction of a femoral fracture (before and after reduction).

Functional Reduction

Functional reduction occurs when the fracture fragments, though not fully restored to normal anatomical relationships, result in a healed fracture with no significant impact on limb function. The standards for functional reduction include:

Complete correction of rotational and translational displacements at the fracture site.
Full correction of angular displacement to avoid uneven stress on the inner and outer sides of the joint, which may predispose to post-traumatic arthritis. For example, minor deformities in humeral shaft fractures have little impact on function.
For transverse fractures of long bone shafts, at least one-third of fracture end apposition should be achieved. For fractures in the metaphysis, at least three-fourths of apposition is required.

Figure 2 Functional reduction of a humeral fracture (with fracture ends aligned by at least one-third).

Methods of Reduction

Two main types of fracture reduction are closed reduction (manual reduction) and open reduction.

Closed Reduction (Manual Reduction)

Closed reduction refers to the use of external manual manipulation to realign fracture fragments or dislocations. During manual reduction, movements need to be gentle, and a single attempt should achieve reduction. Rough manipulation or repeated reduction attempts can aggravate soft tissue damage, impair fracture healing, and increase the risk of complications. Functional alignment should be pursued; otherwise, surgical reduction may be necessary.

Open Reduction

Open reduction involves surgical exposure of the fracture site through an incision, enabling direct visualization of the fragments for alignment.

Indications for open reduction include:

Interposed soft tissues, such as muscles or tendons, between fracture fragments.
Intra-articular fractures.
Fractures with major vascular or nerve injuries.
Multiple fractures.
Unstable fractures such as oblique, spiral, or comminuted fractures in the extremities and spinal fractures with spinal cord injuries.
Limb fractures in elderly patients requiring early mobilization.

Fracture Fixation

Fracture fixation involves two main types: external fixation (placement of devices outside the body) and internal fixation (placement of devices inside the body).

External Fixation

Common external fixation methods include splints, orthopedic braces, plaster bandages, continuous traction, and external fixation devices.

Splints

Splints are made of elastic materials such as willow wood, bamboo, or plastic and are used to immobilize extremity fractures that are closed, non-displaced, and stable. However, their use can lead to complications such as re-displacement of the fracture, pressure ulcers, ischemic muscular contracture, or even gangrene. Consequently, splints are rarely used today.

Figure 3 Splint fixation

Orthopedic Braces

Braces are suitable for stable closed fractures of the extremities and soft tissue injuries around joints.

Plaster Bandages

Indications for plaster bandage fixation include:

Open fractures following wound debridement and suturing.
Certain fractures after internal fixation surgery, such as elastic intramedullary nail fixation for pediatric femoral fractures, as an auxiliary external fixation.
Maintenance of deformity correction, post-osteotomy, or after joint arthrodesis surgery.
Immobilization of limbs affected by purulent arthritis or osteomyelitis to prevent spread of infection.

Figure 4 Plaster bandage fixation for the lower leg

Points to consider:

Elevation of the immobilized limb on a pillow beneath the plaster bandage can help reduce swelling.
During application, assistants should support the limb with their palms rather than pressing with fingers to avoid local pressure ulcers.
The position of the limb, particularly joints, should remain unchanged until the plaster sets.
Skin color, temperature, capillary refill, and motor or sensory function in the distal limb should be regularly monitored. Signs such as persistent severe pain, numbness, purple discoloration, or reduced skin temperature may indicate excessive tightness, requiring immediate longitudinal splitting of the plaster to relieve pressure. Prolonged compression may lead to limb necrosis.
Loosening of the plaster due to subsided swelling reduces its immobilization function, necessitating timely replacement.
While the limb is immobilized, active muscle contractions are encouraged, and unfixed joints should begin early motion.

Head, Neck, and Abduction Braces

Head and neck braces are mainly used for cervical spine injuries, while abduction braces are applied for fractures around the shoulder joint, humeral fractures, and brachial plexus injuries. Positioning the limb in an elevated position aids in reducing swelling and prevents separation and displacement of fractures due to gravity.

Figure 5 Braces used for cervical spine injuries and upper arm fractures or injuries

Continuous Traction

Traction serves both as a method of reduction and external fixation. Types of continuous traction include skin traction, occipito-mandibular traction, and skeletal traction.

Indications for continuous traction include:

Cervical spine fractures or dislocations.
Femoral fractures requiring femoral or tibial tuberosity skeletal traction.
Tibial fractures requiring calcaneal traction.

Figure 6 Occipito-mandibular traction.

Figure 7 Cranial traction.

Figure 8 Supracondylar femoral traction for femoral fractures.

Figure 9 Tibial tuberosity traction for femoral fractures.

Figure 10 Calcaneal traction.

External Fixation Devices

External fixation devices are used for:

Open fractures.
Closed fractures with extensive soft tissue damage.
Fractures complicated by infection or nonunion.
Post-osteotomy deformity correction or joint arthrodesis.

Figure 11 External fixators for open fractures, facilitating wound care.
(1) Bilateral external fixator.
(2) Unilateral external fixator.

Advantages of external fixation devices include reliable immobilization, ease of wound care, preservation of joint movement, and facilitation of early functional exercises.

Internal Fixation

Internal fixation is primarily used after closed or open reduction to secure the repositioned fracture with metallic internal fixation devices such as plates, screws, compression plates, or locking intramedullary nails.

Figure 12 Internal fixation for fractures.
(1) Internal fixation with metallic plates.
(2) Locking intramedullary nail fixation.

Rehabilitation Treatment

Rehabilitation treatment following fractures is of critical importance and serves as a key measure in preventing complications and promoting early functional recovery. Under the guidance of medical professionals, patients are encouraged to participate in early rehabilitation to accelerate fracture healing and restore functionality while minimizing the risk of complications.

Early Stage

During the first one to two weeks after the fracture, the main focus is on improving blood circulation in the injured limb, reducing swelling, and preventing muscle atrophy. Functional exercises consist primarily of active contraction and relaxation of the muscles in the affected limb.

Intermediate Stage

After two weeks, as swelling subsides, local pain diminishes, and fibrous connections form at the fracture site, providing increasing stability, the intensity and range of limb activities can be gradually and slowly increased. This helps prevent muscle atrophy and joint stiffness.

Late Stage

Once clinical standards for fracture healing have been met and external fixation devices have been removed, the late stage becomes the critical period for rehabilitation. Special focus is required for patients who may have received inadequate early or intermediate rehabilitation. Residual limb swelling and joint stiffness can be addressed through exercises aimed at improving joint range of motion and restoring muscle strength.

March

Management of Open Fractures

The principles for managing open fractures focus on timely and appropriate treatment of the wound, minimizing the risk of infection, and converting the open fracture into a closed fracture whenever possible. Delayed treatment can result in severe consequences, including limb dysfunction, disability, or even life-threatening complications.

Figure 1 Open fracture of the distal femur, demonstrating a fracture that communicates with the external environment, presenting a risk of bacterial contamination and infection.

Classification of Open Fractures

Based on the severity of soft tissue damage, open fractures are classified into three degrees:

First Degree: The skin is pierced from the inside out by the fracture ends, with minor soft tissue damage.
Second Degree: The skin is lacerated or crushed, with moderate damage to the subcutaneous and muscle tissues.
Third Degree: Extensive damage to the skin, subcutaneous tissue, and muscles, often accompanied by injuries to blood vessels and nerves.

The Gustilo-Anderson classification further subdivides the third degree into three subtypes:

Type IIIA: Severe soft tissue loss, but the periosteum is able to cover the bone.
Type IIIB: Severe soft tissue loss with bone exposure.
Type IIIC: Severe soft tissue loss with significant vascular injury and bone exposure.

Preoperative Examination and Preparation

This includes:

Collecting the medical history to understand the mechanism of injury, characteristics and timing of the trauma, and details of any emergency care administered.
Assessing the overall condition of the patient, with attention to the presence of shock or injuries to vital organs that could be life-threatening.
Evaluating the affected limb for mobility, sensation, arterial pulses, and peripheral blood circulation to determine whether there are associated injuries to nerves, tendons, or blood vessels.
Examining the wound to estimate the depth of injury, the condition of soft tissue damage, and the degree of contamination.
Performing anteroposterior and lateral X-rays of the injured limb to determine the type and displacement of the fracture. If necessary, CT or MRI imaging can be conducted.

Time to Debridement

For any open fracture, the principle is that the earlier the debridement, the lower the risk of infection, and the better the treatment outcome. Generally, the first 6–8 hours following injury is considered the "golden time" for debridement, as bacteria in contaminated wounds have not yet deeply invaded tissues. Thorough debridement and wound closure during this period can result in primary healing in the majority of cases. After 8 hours, the likelihood of infection increases. However, debridement can still be performed within 24 hours if antibiotics are effectively used. For contaminated wounds beyond 24 hours, bacteria are likely to have invaded deeper tissues, and thorough debridement may no longer be possible. In such cases, simple removal of necrotic tissue and foreign bodies is performed, with drainage established for later-stage treatment. Apart from timing, the degree of contamination is a critical factor, with higher degrees of contamination corresponding to higher infection risks.

Key Points in Debridement

Debridement for open fractures involves wound debridement, fracture stabilization, soft tissue repair, and wound closure, with stricter requirements compared to the management of simple soft tissue injuries. Infection can result in suppurative osteomyelitis if not properly managed.

Debridement

Debridement refers to the process of transforming a contaminated wound into a clean wound through washing, disinfection, excision of wound edges, removal of foreign materials, and excision of necrotic and non-viable tissues. The procedure is typically performed under brachial plexus block, epidural anesthesia, or general anesthesia. To reduce bleeding, especially in cases involving vascular injury, a tourniquet can be used during the operation. Since the use of a tourniquet makes it difficult to assess the blood supply of tissues, it is necessary to release the tourniquet after debridement and hemostasis to ensure that tissues without blood supply are thoroughly excised.

Cleansing

The wound is covered with sterile dressings, and the affected limb is scrubbed with a sterile brush and soapy solution 2–3 times. The scrubbed area includes the joints above and below the wound. The area is rinsed with sterile saline before routine disinfection and draping, after which the debridement procedure is performed.

Excision of Wound Edges

Approximately 1–2 mm of wound-edge skin is excised. For skin with contusions, non-viable skin is removed. Foreign materials are cleared from superficial to deep layers, while contaminated and non-viable subcutaneous tissues, fascia, and muscles are excised. Tendons, nerves, and blood vessels are preserved and repaired following the removal of contaminated tissues.

Management of Joint Ligaments and Joint Capsules

In cases of severe contusion of joint ligaments and joint capsules, excision is performed. For ligaments or capsules that are only contaminated, as much as possible, these structures are preserved after the contaminants are thoroughly removed. Preservation is important for joint stability and functional recovery.

Periosteum Handling

Preservation of the periosteum is recommended whenever possible, as it facilitates bone healing. If the periosteum is contaminated, its surface can be carefully excised.

Treatment of Fracture Ends

The fracture ends are thoroughly cleaned while maintaining bone integrity as much as possible to support fracture healing. Contaminated portions of bone are managed using bone chisels or rongeurs, while cancellous bone can be scraped clean. The contaminated medullary cavity is completely cleaned.

For comminuted fractures, fragments of bone should be carefully managed. Small fragments should be assessed based on whether they have soft tissue attachments. Larger fragments, especially those still connected to surrounding tissues, are preserved to avoid bone defects that would impair fracture healing.

Secondary Cleansing

After the initial cleansing, the wound and surrounding tissues are washed again 2–3 times with sterile saline to remove debris from damaged tissues that may not be visible to the naked eye. The wound is then soaked or dressed with 0.1% povidone-iodine for 3–5 minutes to eliminate residual bacteria.

Fracture Fixation and Tissue Repair

Fracture Fixation

After debridement, the fracture is reduced under direct visualization, and an appropriate internal fixation method is selected based on the type of fracture. The fixation methods should prioritize simplicity and speed, with external fixation utilized postoperatively if necessary.

In the case of Grade III open fractures or Grade II fractures where debridement is delayed beyond 6–8 hours after injury, internal fixation is not recommended. External fixators may be used instead. This is due to the fact that after 6–8 hours, bacteria in the wound have typically passed through the incubation period and entered a logarithmic growth phase. Internal fixation materials, as inert foreign objects, can exacerbate infection risks due to reduced local tissue resistance and limited efficacy of antibiotics. However, with advancements in surgical techniques and the rational application of highly effective antibiotics in recent years, internal fixation is now considered feasible after debridement of open fractures.

Repair of Critical Soft Tissues

Damage to critical structures such as tendons, nerves, and blood vessels should be addressed by adopting appropriate repair methods during debridement whenever possible to promote early functional recovery.

Wound Drainage

A silicone drainage tube is placed in the deepest part of the wound, routed through normal skin to the exterior, and connected to a negative-pressure drainage bottle. The tube is typically removed after 24–48 hours. If necessary, prior to wound closure, slow-release antibiotic agents may be introduced into the wound cavity.

Wound Closure

Achieving complete wound closure with primary healing is critical for converting open fractures into closed fractures. This is also the primary goal of debridement procedures. For Grade I and II open fractures, most wounds can achieve primary closure following debridement. For Grade III open fractures, temporary coverage of the wound with polymer materials, such as vacuum-assisted closure (VAC) devices, can be employed after debridement. Once swelling subsides, the wound can be directly sutured or managed with free skin grafting.

Tension-Reducing Sutures and Skin Grafting

For cases with skin defects and significant wound tension where direct suturing is not possible, tension-reducing incisions parallel to the wound on one or both sides may be performed if the surrounding skin and soft tissues are relatively intact. The tension-relief incisions may be directly sutured if feasible; otherwise, skin grafting can be performed over these incisions. If skin defects exist at the wound site but the local soft tissue bed is suitable, and no major structures such as bone, nerves, or blood vessels are exposed, direct skin grafting over the wound is also an option.

Figure 2 Illustration of tension-relieving incisions and suturing for skin defects.
(1) Excision of wound edges, (2) Tension-relief incision, (3) Wound suturing.

Flap Transplantation

Grade III open fractures with extensive soft tissue damage often feature exposed bones and a lack of soft tissue coverage. Such cases carry a high risk of infection. Appropriate skin flaps should be used to cover the wound.

Completion of the Debridement Process

After the debridement process, an appropriate fixation method is selected to immobilize the affected limb according to the condition of the injury. Preventative measures against infection should include the use of antibiotics and administration of tetanus antitoxin as needed.

March

Principles of Managing Open Joint Injuries

An open joint injury refers to a situation where the skin and joint capsule are ruptured, resulting in communication between the joint cavity and the external environment. The principles for managing such injuries are largely similar to those for open fractures, with the primary objectives being to prevent joint infection and restore joint function. The extent of the injury determines the approach to treatment and the postoperative outcomes, which can generally be classified into three degrees.

First-Degree Injury

A sharp object penetrates the joint capsule, causing a small wound, with no damage to the articular cartilage or bones. Such injuries do not require the joint to be opened, as this could risk further contamination. After debridement and suturing of the wound, antibiotics can be injected into the joint, followed by appropriate immobilization for three weeks. Joint function exercises can then begin. If joint swelling or effusion occurs, it should be managed as an early case of pyogenic arthritis.

Second-Degree Injury

There is extensive soft tissue damage, partial destruction of the articular cartilage and bones, and foreign bodies within the wound. After completing soft tissue debridement locally, gloves, dressings, and instruments should be changed before enlarging the joint capsule incision to fully expose the joint. The joint should be thoroughly flushed with normal saline. Foreign bodies, hematomas, and small bone fragments within the joint should be completely removed, while larger bone fragments should be reduced and fixed to maintain the integrity of the articular cartilage surface. The joint capsule and ligaments should be preserved as much as possible and repaired. Defects in the joint capsule can be repaired using fascia. If necessary, a silicone tube can be placed within the joint cavity, and postoperatively, it can be irrigated and drained with Ringer's solution containing antibiotics, with the tube removed after 48 hours.

Third-Degree Injury

There is severe soft tissue damage, ligament rupture, and serious injury to the articular cartilage and bones, with foreign bodies present in the wound. There may also be associated joint dislocation and injuries to blood vessels and nerves. After thorough debridement, the wound can be left open with moist dressings applied under sterile conditions, and delayed closure can be performed in 3 to 5 days. Alternatively, after thorough debridement, large soft tissue defects can be repaired using microsurgical techniques, such as myocutaneous or cutaneous flap transplantation. If joint function cannot be restored, joint fusion can be performed in one stage.

March

Management of Delayed Union, Nonunion, and Malunion of Fractures

Delayed Union

Delayed union refers to a fracture that, after treatment, takes longer than the usual time required for healing (typically 4 to 8 months) and still shows no evidence of bone union. On X-ray imaging, the fracture ends exhibit minimal callus formation, mild decalcification, and a clearly visible fracture line, but without signs of bone sclerosis.

Figure 1 Despite exceeding the typical healing time, the fracture ends show no evidence of bone union.

Nonunion

Nonunion refers to a fracture that, despite treatment and exceeding the typical healing time (9 months), fails to achieve bone union even after an additional period of delayed treatment (approximately 3 months). Based on X-ray findings, nonunion can be categorized into hypertrophic and atrophic types.

Hypertrophic nonunion is characterized by enlargement and sclerosis at the fracture ends, which appear club-like on X-rays. This indicates bone regeneration has occurred, but due to a lack of stability at the fracture site, the new callus fails to bridge the fracture line.

Atrophic nonunion shows no callus formation at the fracture ends. The fracture ends appear separated, atrophied, and exhibit poor vascularity, indicating no bone regeneration. The medullary cavity is sealed by dense, sclerotic bone.

Figure 2 The two fracture ends appear atrophied and smooth, with the medullary cavity sealed by dense, sclerotic bone.

Nonunion often results from factors such as interposition of soft tissue at the fracture ends, large bone defects from extensive debridement in open fractures, repeated surgeries disrupting blood supply to the bone, or failure of internal fixation. Nonunion cannot be resolved by merely extending the treatment duration. Resolution requires removal of sclerotic bone, re-establishing the medullary cavity, and repairing bone defects. Typically, bone grafting and internal fixation are necessary, and in some cases, external fixation may be combined for treatment.

Malunion

Malunion occurs when a fracture heals in a position that does not meet functional alignment requirements, resulting in angular, rotational, or overlapping deformities. Malunion is often caused by inadequate fracture reduction, insufficient fixation, premature removal of fixation devices, or the influence of muscle pull, limb weight, or inappropriate loading at the fracture site. Mild deformities with limited functional impact may not require intervention. However, significant deformities that affect limb function require corrective procedures.

Figure 3 Malunion presents with angular, rotational, and overlapping deformities after fracture healing.