Galeazzi vs Monteggia Fracture: Key Differences

Galeazzi fracture and Monteggia fracture represent distinct upper limb injuries, each characterized by a unique combination of bone fractures and joint dislocations. Specifically, a Galeazzi fracture involves a fracture of the radius bone, typically located in the distal third, coupled with a disruption of the distal radioulnar joint (DRUJ); the DRUJ’s stability is critical for forearm rotation. Conversely, a Monteggia fracture features a fracture of the ulna bone along with a dislocation of the radial head at the elbow joint, which directly impacts the elbow's biomechanical function. Understanding the nuanced differences in these fractures is vital for orthopedic surgeons who specialize in trauma surgery because appropriate diagnosis and management prevent long-term complications affecting the patient’s functionality.

Monteggia and Galeazzi fracture-dislocations represent a distinct set of upper extremity injuries demanding astute clinical acumen. These are not merely fractures of the forearm; they are complex injuries characterized by a fracture in one forearm bone coupled with a dislocation at a nearby joint. Their precise identification and management are critical to ensure optimal patient outcomes.

Defining Monteggia Fracture-Dislocation

A Monteggia fracture-dislocation is defined as a fracture of the ulna combined with a dislocation of the radial head at the elbow.

This injury disrupts the normal biomechanical relationship between the radius and ulna. This disruption subsequently impacts the stability and function of the elbow and forearm.

Defining Galeazzi Fracture-Dislocation

Conversely, a Galeazzi fracture-dislocation involves a fracture of the radius, usually at the distal third, accompanied by disruption of the distal radioulnar joint (DRUJ).

This combination injury results in instability of the wrist and compromises forearm rotation. Unlike isolated fractures, Galeazzi lesions involve both bony and ligamentous structures.

The Critical Importance of Accurate Diagnosis

The significance of recognizing and appropriately treating Monteggia and Galeazzi fracture-dislocations cannot be overstated. Missed or delayed diagnoses, or inadequate treatment, can lead to significant long-term functional deficits.

These deficits include chronic pain, limited range of motion, instability, and decreased grip strength. Such outcomes can profoundly impact a patient's ability to perform activities of daily living and return to work or recreational activities. Early, accurate diagnosis is paramount.

Common Mechanisms of Injury

Understanding the mechanisms by which these injuries occur is crucial for both diagnosis and prevention.

Monteggia fractures commonly result from a fall on an outstretched hand with the forearm in pronation, or from a direct blow to the ulna.

Galeazzi fractures often occur due to a direct blow to the wrist or a twisting injury of the forearm, or from a fall onto an outstretched hand with the wrist in an extended and pronated position.

The forces involved are often high-energy, reflecting the complex nature of these injuries.

Forearm Anatomy: The Foundation for Understanding Injury Patterns

Monteggia and Galeazzi fracture-dislocations represent a distinct set of upper extremity injuries demanding astute clinical acumen. These are not merely fractures of the forearm; they are complex injuries characterized by a fracture in one forearm bone coupled with a dislocation at a nearby joint. Their precise identification and management are critically dependent upon a comprehensive understanding of forearm anatomy.

The Radius and Ulna: A Functional Partnership

The forearm's structural integrity and functional versatility stem from the intricate interplay between the radius and ulna. These bones, connected by the interosseous membrane, work in concert to facilitate pronation and supination—movements crucial for hand positioning and object manipulation.

The radius, located on the thumb side of the forearm, is the primary bone responsible for wrist articulation and contributes significantly to forearm rotation. In contrast, the ulna, situated on the pinky finger side, provides stability to the elbow joint and serves as the main axis for forearm rotation.

The Proximal Radioulnar Joint (PRUJ) and Monteggia Fractures

The proximal radioulnar joint (PRUJ) is a pivot joint located near the elbow, allowing the radius to rotate around the ulna. Disruption of the PRUJ is a hallmark of Monteggia fractures.

In these injuries, a fracture of the ulna is typically accompanied by dislocation of the radial head from the PRUJ. This dislocation can compromise forearm stability and function, leading to pain, limited range of motion, and potential nerve injury.

The Distal Radioulnar Joint (DRUJ) and Galeazzi Fractures

The distal radioulnar joint (DRUJ), located near the wrist, mirrors the function of the PRUJ, enabling forearm rotation at the wrist. Instability or disruption of the DRUJ is a key characteristic of Galeazzi fractures.

These injuries involve a fracture of the radius, usually in its distal third, coupled with disruption of the DRUJ. The DRUJ disruption can manifest as subluxation (partial dislocation) or complete dislocation, leading to wrist pain, instability, and impaired grip strength.

The Interosseous Membrane: A Stabilizing Force

The interosseous membrane is a strong, fibrous sheet that connects the radius and ulna along their entire length. It plays a crucial role in distributing forces between the two bones and maintaining forearm stability.

Disruption of the interosseous membrane is a common feature of Galeazzi fractures, contributing significantly to DRUJ instability. When the radius fractures and the DRUJ dislocates, the interosseous membrane often tears or stretches, further compromising forearm stability.

Capitellum Articulation and Associated Injuries

The capitellum is the rounded, lateral portion of the distal humerus that articulates with the radial head. This articulation allows for smooth movement at the elbow joint, particularly during flexion and extension.

In the context of Monteggia fractures, the forceful dislocation of the radial head can lead to chondral (cartilage) or osseous (bone) damage to the capitellum. Such injuries can result in persistent pain, stiffness, and the development of post-traumatic arthritis.

The Annular Ligament: Guardian of Radial Head Stability

The annular ligament is a strong, circular band that encircles the radial head, securing it within the PRUJ. It is a primary stabilizer of the radial head, preventing its anterior, posterior, or lateral displacement.

In Monteggia fractures, the annular ligament is often torn or stretched due to the forceful dislocation of the radial head. This ligamentous injury contributes to chronic instability of the PRUJ, increasing the risk of recurrent radial head dislocations.

Radial Nerve Vulnerability

The radial nerve courses along the lateral aspect of the humerus and forearm, providing motor innervation to the wrist and finger extensors, as well as sensory innervation to the dorsum of the hand.

Both Monteggia and Galeazzi fractures can place the radial nerve at risk of injury. Mechanisms of nerve damage include direct compression by fracture fragments, traction due to bony displacement, or laceration by sharp bone edges. Radial nerve injury can result in wrist drop, finger extension weakness, and sensory loss in the hand.

Posterior Interosseous Nerve (PIN) Considerations

The posterior interosseous nerve (PIN) is a branch of the radial nerve that supplies motor innervation to the wrist and finger extensors on the dorsal side of the forearm.

In Monteggia fractures, the PIN is particularly vulnerable to injury as it courses around the radial neck, near the site of radial head dislocation. PIN injury can lead to weakness or paralysis of the finger extensors, resulting in difficulty straightening the fingers.

Muscular Influences on Fracture Displacement

The muscles of the forearm play a significant role in fracture displacement and stability. Muscles such as the biceps brachii, pronator teres, and supinator can exert considerable force on fracture fragments, influencing their alignment and stability.

Understanding the muscle attachments and their lines of pull is crucial for achieving adequate fracture reduction and preventing secondary displacement. Surgical fixation techniques often take into account the muscular forces acting on the fracture site.

Classifying the Injuries: Bado and Galeazzi Equivalent

Forearm Anatomy: The Foundation for Understanding Injury Patterns Monteggia and Galeazzi fracture-dislocations represent a distinct set of upper extremity injuries demanding astute clinical acumen. These are not merely fractures of the forearm; they are complex injuries characterized by a fracture in one forearm bone coupled with a dislocation at a radio-ulnar joint. This section will explore the classification systems used to categorize Monteggia and Galeazzi fractures. Understanding these classifications is essential for guiding treatment decisions and predicting outcomes.

The Bado Classification: A Cornerstone for Monteggia Fractures

The Bado classification, developed by Joseph Bado in 1967, serves as the primary system for categorizing Monteggia fractures. This classification is based on the direction of the radial head dislocation in relation to the fractured ulna. A clear understanding of the Bado classification is paramount for effective communication and treatment planning.

Bado Type I

Bado Type I fractures are characterized by a fracture of the ulnar shaft with anterior dislocation of the radial head. This is the most common type of Monteggia fracture.

The mechanism typically involves a fall on an outstretched hand with the forearm in pronation. Treatment usually involves open reduction and internal fixation (ORIF) of the ulna fracture, which indirectly reduces the radial head dislocation.

Bado Type II

Bado Type II fractures involve a fracture of the ulnar shaft with posterior dislocation of the radial head.

These injuries are less common than Type I fractures. They often result from direct trauma to the posterior aspect of the forearm. ORIF of the ulna is the standard treatment, often combined with ligamentous repair.

Bado Type III

Bado Type III fractures consist of an ulnar metaphyseal fracture with lateral dislocation of the radial head.

These are relatively rare and are more commonly seen in children. Given the metaphyseal fracture, treatment may involve closed reduction and casting, particularly in younger patients. However, ORIF may be necessary in unstable fractures or in older individuals.

Bado Type IV

Bado Type IV fractures involve a fracture of both the ulna and radius at the same level, with anterior dislocation of the radial head. This is the least common type of Monteggia fracture.

These injuries are highly unstable and typically require ORIF of both the radius and ulna. The presence of fractures in both bones complicates the injury pattern and increases the risk of complications.

Clinical Relevance of the Bado Classification

The Bado classification is not merely a descriptive tool; it directly informs treatment strategies and helps predict potential complications.

For instance, Type I fractures are often associated with radial nerve injuries, while Type II fractures may involve damage to the posterior interosseous nerve. Understanding these associations allows surgeons to anticipate and address potential nerve-related issues during treatment.

The Bado classification also guides the choice of surgical approach and fixation techniques.

The Galeazzi Equivalent: Beyond the Classic Definition

While the classic Galeazzi fracture involves a fracture of the distal radius with disruption of the distal radioulnar joint (DRUJ), the term "Galeazzi equivalent" is used to describe similar injuries that do not precisely fit the classic definition.

These variants can include fractures of the radial shaft with DRUJ instability, or injuries involving the interosseous membrane without a distinct fracture.

The key feature of a Galeazzi equivalent is the disruption of the forearm's longitudinal stability, leading to DRUJ instability.

Recognizing Galeazzi equivalents is critical because these injuries also require surgical stabilization to restore forearm mechanics and prevent long-term complications. Examples of Galeazzi equivalents include isolated interosseous membrane tears with DRUJ instability, or subtle radial shaft fractures that compromise DRUJ stability.

Accurate classification using the Bado system and vigilant recognition of Galeazzi equivalents are essential for ensuring optimal outcomes in patients with these complex forearm injuries.

Diagnosis: Identifying Monteggia and Galeazzi Fractures

Forearm Anatomy: The Foundation for Understanding Injury Patterns Monteggia and Galeazzi fracture-dislocations represent a distinct set of upper extremity injuries demanding astute clinical acumen. These are not merely fractures of the forearm; they are complex injuries characterized by a fracture of one forearm bone accompanied by a dislocation of a radio-ulnar joint. Accurate and timely diagnosis is paramount to prevent long-term functional impairment. This section will delve into the essential diagnostic procedures used to identify these complex injuries, focusing on clinical evaluation and various imaging techniques.

Clinical Evaluation: The First Step Towards Diagnosis

The diagnostic process for suspected Monteggia or Galeazzi fractures begins with a thorough clinical evaluation. This involves a detailed patient history and a comprehensive physical examination.

Understanding the mechanism of injury is crucial. The way in which the injury occurred can provide valuable clues about the type and severity of the fracture-dislocation.

For example, a fall on an outstretched hand with forced pronation might suggest a Galeazzi fracture.

Key Physical Examination Findings

The physical examination should focus on identifying specific signs and symptoms indicative of these injuries.

• Pain: Localized pain, often intense, is a common finding. Palpation along the radius and ulna should be performed to identify the point of maximal tenderness.

• Deformity: Visible deformity of the forearm, particularly angulation or shortening, may be present. This is often more pronounced in displaced fractures.

• Limited Range of Motion: Significant restriction in forearm rotation (pronation and supination) is a characteristic sign. Pain often exacerbates the limitation.

• Swelling and Ecchymosis: Swelling and bruising are common findings, often developing rapidly after the injury.

• Neurological Assessment: A careful neurological examination is essential to assess for any nerve injury, especially to the radial nerve and its branches. Document any sensory or motor deficits.

X-ray (Radiography): The Gold Standard for Confirmation

Radiography, or X-ray imaging, serves as the cornerstone of diagnosis for Monteggia and Galeazzi fractures. It provides a clear visualization of the bony structures and any associated dislocations.

Importance of Appropriate Views

Obtaining appropriate radiographic views is critical for accurate assessment. The standard protocol includes:

• Anteroposterior (AP) View: This view provides an assessment of the alignment and integrity of the radius and ulna in the coronal plane. It helps identify fractures, dislocations, and any displacement.

• Lateral View: The lateral view allows visualization of the forearm bones in the sagittal plane. It is essential for detecting angulation, posterior or anterior displacement, and dislocations of the radial head or distal radioulnar joint.

Interpreting Radiographic Findings

Careful interpretation of the radiographs is paramount. In Monteggia fractures, look for a fracture of the ulna in combination with a dislocation of the radial head at the elbow. In Galeazzi fractures, identify a fracture of the radius accompanied by a disruption of the distal radioulnar joint (DRUJ).

Computed Tomography (CT Scan): Assessing Complex Injuries

Computed Tomography (CT) scans are valuable in evaluating complex fracture patterns and assessing joint involvement.

CT imaging provides detailed cross-sectional images of the forearm, offering superior visualization of fracture fragments, intra-articular involvement, and subtle dislocations compared to standard radiographs.

This is particularly useful in cases with significant comminution (multiple fracture fragments) or when surgical planning requires a more precise understanding of the fracture anatomy.

Magnetic Resonance Imaging (MRI): Visualizing Soft Tissue Injuries

Magnetic Resonance Imaging (MRI) is primarily used to assess soft tissue injuries associated with Monteggia and Galeazzi fractures.

MRI excels at visualizing ligaments, tendons, muscles, and cartilage, which are not clearly visible on X-rays or CT scans. In Monteggia and Galeazzi injuries, MRI can help identify:

• Ligament Tears: Assessment of collateral ligaments for tears.
• Cartilage Damage: Evaluation of chondral injuries.
• Interosseous Membrane Injuries: Evaluation of any tears in the interosseous membrane.

While not always necessary for the initial diagnosis of the fracture itself, MRI plays a crucial role in identifying concomitant soft tissue injuries that may impact treatment decisions and long-term outcomes.

Treatment Strategies: From Non-Operative to Surgical Intervention

[Diagnosis: Identifying Monteggia and Galeazzi Fractures Forearm Anatomy: The Foundation for Understanding Injury Patterns Monteggia and Galeazzi fracture-dislocations represent a distinct set of upper extremity injuries demanding astute clinical acumen. These are not merely fractures of the forearm; they are complex injuries characterized by a fracture combined with joint instability. As such, successful management necessitates a thorough understanding of the available treatment strategies, ranging from conservative non-operative approaches to sophisticated surgical interventions. The overarching goal remains the restoration of forearm anatomy and function, thus minimizing long-term morbidity.

Navigating the Treatment Landscape

The choice between non-operative and operative management hinges on several critical factors. These include the patient's age, overall health, the severity and pattern of the fracture-dislocation, and the presence of associated injuries. While non-operative treatment may be considered in select cases, surgical intervention often represents the gold standard for achieving optimal outcomes in Monteggia and Galeazzi fractures.

The Role of Non-Operative Management

Non-operative management for Monteggia and Galeazzi fracture-dislocations is generally reserved for specific scenarios, primarily in stable, non-displaced fractures or in very young children where remodeling potential is high.

Indications and Limitations

The indications for non-operative treatment are limited. They typically include incomplete fractures (greenstick fractures) in children with minimal displacement and stable reductions. However, it's crucial to acknowledge the limitations. These include the potential for loss of reduction, delayed union, and malunion, all of which can compromise long-term function.

Splinting and Casting Techniques

When non-operative management is deemed appropriate, immobilization is paramount. This is typically achieved through the application of a long arm splint or cast. The position of immobilization (pronation, supination, or neutral) depends on the specific fracture pattern and the goal of maintaining reduction.

Serial radiographs are essential to monitor the fracture alignment and ensure that reduction is maintained throughout the healing process.

Pain Management

Effective pain management is a crucial component of non-operative treatment. This may involve the use of oral analgesics, such as acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs). In some cases, stronger opioid medications may be required for short-term pain relief.

General Principles of Orthopedic Surgery

Orthopedic surgery aims to restore the normal anatomy of the forearm and stabilize the fracture. This often involves open reduction and internal fixation (ORIF). The goal is to achieve a stable, anatomical reduction that promotes bone healing and restores proper joint mechanics.

Open Reduction and Internal Fixation (ORIF)

ORIF is the most common surgical approach for Monteggia and Galeazzi fractures. This technique involves surgically exposing the fracture site, reducing the fracture fragments to their anatomical position, and then stabilizing them with internal fixation devices.

Surgical Technique

The specific surgical technique varies depending on the fracture pattern and the surgeon's preference. However, the general principles remain the same. The fracture site is carefully exposed, hematoma and debris are removed, and the fracture fragments are mobilized.

The fracture is then reduced, and temporary fixation is achieved with Kirschner wires (K-wires). Once satisfactory reduction is confirmed, definitive fixation is performed with plates and screws.

Plates and Screws

Plates and screws are the most commonly used internal fixation devices for Monteggia and Galeazzi fractures. Plates provide stable fixation and resist bending and torsional forces. Screws are used to compress the fracture fragments and secure the plate to the bone. The specific type of plate and screw used depends on the fracture pattern, bone quality, and surgeon's preference.

The Pivotal Role of Physical Therapy

Rehabilitation plays a critical role in regaining optimal function after a Monteggia or Galeazzi fracture, regardless of whether the treatment was operative or non-operative. Physical therapy helps restore range of motion, strength, and coordination.

Range of Motion (ROM) Exercises

Early range of motion exercises are essential to prevent stiffness and contractures. These exercises should be initiated as soon as pain allows and should be performed under the guidance of a qualified physical therapist. As healing progresses, more aggressive strengthening exercises can be introduced to restore muscle strength and endurance.

Complications: Addressing Potential Challenges

While meticulous surgical technique and diligent post-operative care significantly improve outcomes, Monteggia and Galeazzi fracture-dislocations are complex injuries with potential for complications. This section addresses these challenges, providing insight into their risks, diagnosis, and management.

Open Fractures and Infection Risk

Open fractures, where the bone penetrates the skin, pose a significant risk of infection. The severity of the soft tissue injury directly correlates with the probability of infection.

Infection Management Strategies

Prompt and aggressive management is crucial. This includes:

• Intravenous Antibiotics: Broad-spectrum antibiotics are initiated immediately to combat potential bacterial contamination. The specific antibiotics are then tailored based on cultures obtained during surgical debridement.

• Surgical Debridement: This involves thorough irrigation and removal of all devitalized tissue and foreign material from the fracture site. Repeat debridements may be necessary to ensure complete removal of contamination.

• Fracture Stabilization: Stabilizing the fracture, usually with internal or external fixation, is essential for promoting bone healing and reducing the risk of chronic infection.

Impact of Displacement and Angulation

Even with closed fractures, achieving and maintaining anatomical reduction is paramount. Residual displacement or angulation can lead to long-term functional deficits.

These include:

• Limited Range of Motion: Malalignment can restrict pronation and supination, impacting daily activities.

• Chronic Pain: Abnormal joint mechanics can contribute to chronic pain and discomfort.

• Arthritis: Over time, malalignment can accelerate the development of arthritis in the elbow or wrist.

Compartment Syndrome: A Limb-Threatening Emergency

Compartment syndrome is a condition where increased pressure within a confined fascial compartment compromises the circulation and function of the tissues within that space. It is a limb-threatening emergency requiring immediate recognition and treatment.

Etiology and Diagnosis

Compartment syndrome can arise from:

• Fracture Hematoma: Bleeding associated with the fracture can increase pressure.

• Soft Tissue Swelling: Significant soft tissue injury contributes to swelling.

• External Compression: Tight casts or dressings can exacerbate the condition.

The diagnosis is primarily clinical, based on the "5 Ps": Pain out of proportion, Pallor, Paresthesia, Pulselessness, and Paralysis. However, pulselessness is a late finding, and the diagnosis should be made before it occurs. Direct compartment pressure measurements can also aid in diagnosis.

Urgent Management

The treatment for compartment syndrome is emergent fasciotomy. This involves surgically releasing the fascia to decompress the affected compartments and restore blood flow.

• Fasciotomy: Surgical release of the fascial compartments to relieve pressure.

• Wound Management: Open wounds are managed with sterile dressings and potential delayed closure or skin grafting.

Nonunion and Malunion: When Healing Fails

Nonunion refers to the failure of a fracture to heal, while malunion refers to healing in an unacceptable position.

Definition and Causes

• Nonunion: Fracture fails to heal within the expected timeframe. Factors include inadequate blood supply, infection, instability, and patient factors like smoking.

• Malunion: Fracture heals in a deformed position. This can be due to inadequate reduction, loss of fixation, or failure to comply with post-operative instructions.

Revision Surgical Options

Both nonunion and malunion often require revision surgery. These options include:

• Bone Grafting: To stimulate bone healing in nonunions.

• Osteotomy: To correct malalignment in malunions.

• Revision Fixation: Replacing or augmenting the fixation to provide stability.

Historical Context: Honoring the Pioneers

Complications: Addressing Potential Challenges While meticulous surgical technique and diligent post-operative care significantly improve outcomes, Monteggia and Galeazzi fracture-dislocations are complex injuries with potential for complications. This section addresses these challenges, providing insight into their risks, diagnosis, and management. However, before diving deeper into contemporary approaches, we must first acknowledge the historical figures who laid the foundation for our current understanding of these injuries. Their astute observations and dedication to advancing orthopedic knowledge continue to guide our practice.

Ricardo Galeazzi: Defining the Distal Radioulnar Joint Injury

Ricardo Galeazzi, an Italian surgeon, is forever linked to the fracture-dislocation bearing his name. In 1934, Galeazzi meticulously described the injury pattern involving a fracture of the radius with disruption of the distal radioulnar joint (DRUJ).

His work highlighted the importance of recognizing the DRUJ instability, which is crucial for proper treatment and restoration of forearm function. Galeazzi's detailed clinical observations and radiographic analysis provided a clear framework for diagnosis.

He emphasized the challenges in achieving and maintaining reduction of the DRUJ, and the functional consequences of overlooking this component of the injury. Galeazzi's contribution was not merely descriptive; it was a call to action, urging surgeons to carefully assess and address the DRUJ in these fractures.

Giovanni Battista Monteggia: Unraveling the Proximal Ulna Fracture

Giovanni Battista Monteggia, another Italian surgeon, predates Galeazzi by over a century. In the early 19th century, Monteggia described the fracture-dislocation that now bears his name: a fracture of the ulna with dislocation of the radial head at the elbow.

Monteggia's astute observation linked these two seemingly disparate injuries, recognizing that they often occurred together as a single complex injury pattern. He understood that a fracture of the ulna could disrupt the alignment and stability of the elbow joint, leading to radial head dislocation.

His contribution was foundational in recognizing the importance of a comprehensive radiographic evaluation of the entire forearm and elbow when encountering an ulna fracture. Monteggia's legacy reminds us to look beyond the obvious fracture and assess the entire limb for associated injuries.

Contemporary Approaches: Building Upon the Legacy

Modern orthopedic surgeons stand on the shoulders of giants like Galeazzi and Monteggia. While the fundamental principles of diagnosis and treatment remain rooted in their observations, contemporary approaches have been refined and enhanced by advancements in technology and surgical techniques.

The advent of improved imaging modalities, such as CT scans and MRI, allows for more detailed assessment of fracture patterns and soft tissue injuries. This has led to more precise surgical planning and improved outcomes.

The development of advanced fixation devices, such as anatomical plates and bioabsorbable sutures, has facilitated more stable and reliable fracture fixation. Contemporary surgeons increasingly emphasize restoring anatomical alignment, achieving stable fixation, and promoting early range of motion to optimize functional outcomes.

The use of minimally invasive surgical techniques is gaining traction in select cases, aiming to reduce soft tissue damage and accelerate recovery. Furthermore, a growing body of research is focused on understanding the biomechanics of these injuries, leading to evidence-based treatment protocols. The legacy of Galeazzi and Monteggia lives on, inspiring ongoing innovation and refinement in the management of these challenging injuries.

So, there you have it! Hopefully, this clears up the confusion between a Galeazzi fracture and a Monteggia fracture. While both involve forearm fractures, remembering which bone is broken and where the dislocation occurs is key. If you're ever faced with either a Galeazzi fracture or a Monteggia fracture, knowing the difference can make a real difference in getting the right treatment.