Fracture Of Greater Tubercle Of Humerus

Fracture of the Greater Tubercle of the Humerus: A Comprehensive Overview

The greater tubercle of the humerus, a bony prominence on the proximal humerus, plays a crucial role in shoulder stability and function. Fractures of this structure, while less common than other humeral fractures, present unique challenges in diagnosis and management. This comprehensive article delves into the epidemiology, mechanisms of injury, clinical presentation, diagnostic approaches, treatment options, and rehabilitation strategies associated with greater tubercle fractures. Understanding these aspects is critical for orthopedic surgeons and healthcare professionals involved in the care of patients with this injury.

Epidemiology and Mechanism of Injury

Greater tubercle fractures constitute a relatively small percentage of all humeral fractures, typically accounting for less than 5% of proximal humeral fractures. They primarily affect adults, particularly those in the older age groups, and are more prevalent in women. This disparity may be attributed to factors such as bone density and hormonal influences.

The mechanisms of injury are diverse, commonly involving:

1. Falls on the Outstretched Hand (FOOSH):

This is the most frequent mechanism. The impact force transmits along the arm, concentrating stress on the greater tubercle, leading to a fracture. The severity of the fracture often correlates with the energy of the fall.

2. Direct Trauma:

Direct blows to the shoulder region, such as those sustained in motor vehicle accidents or sports injuries, can also result in greater tubercle fractures.

3. Muscle Avulsion:

Powerful contractions of the rotator cuff muscles, especially the supraspinatus, can avulse a portion of the greater tubercle. This mechanism is more common in younger, athletic individuals.

Clinical Presentation

Patients with greater tubercle fractures often present with a constellation of symptoms, including:

• Pain: Localized pain over the lateral aspect of the shoulder is the hallmark symptom. Pain is typically exacerbated by shoulder movement, particularly abduction and external rotation.
• Swelling: Significant swelling and ecchymosis (bruising) may be present in the affected area.
• Tenderness: Palpation of the greater tubercle elicits marked tenderness.
• Limited Range of Motion: Patients experience restricted active and passive range of motion (ROM) in the shoulder joint. Abduction and external rotation are commonly affected.
• Deformity: A palpable step-off deformity may be evident in cases of displaced fractures. However, this is not always present.
• Weakness: Weakness in shoulder abduction, due to supraspinatus involvement, is a frequent finding.

Diagnostic Evaluation

Accurate diagnosis of a greater tubercle fracture necessitates a combination of clinical examination and imaging studies:

1. Physical Examination:

A thorough physical examination focusing on shoulder ROM, palpation for tenderness and deformity, and assessment of muscle strength is essential. Neurovascular examination is crucial to rule out associated nerve or vascular injuries.

2. Imaging:

• X-rays: Plain radiographs, including anteroposterior (AP), lateral, and axillary views, are the initial imaging modality of choice. These images allow for visualization of the fracture, assessment of displacement, and identification of any associated injuries.
• Computed Tomography (CT) scan: CT scans provide superior detail of the fracture morphology, particularly in complex fractures or cases with subtle involvement. They help in planning surgical intervention.
• Magnetic Resonance Imaging (MRI): MRI is less frequently used for initial diagnosis but can be helpful in evaluating associated rotator cuff tears or other soft tissue injuries. It provides excellent soft tissue contrast and helps to assess the extent of injury to the surrounding structures.

Treatment Options

Treatment approaches for greater tubercle fractures are tailored to individual patient factors, considering the fracture pattern, degree of displacement, patient age, and activity level. The treatment options can be broadly classified into:

1. Non-Operative Management:

Non-surgical management is generally reserved for minimally displaced or undisplaced fractures in older, less active individuals. It involves:

• Immobilization: The arm is immobilized using a sling and swathe for 4-6 weeks.
• Pain Management: Analgesics and anti-inflammatory medications are used to control pain.
• Physical Therapy: Post-immobilization, a structured physical therapy program focuses on restoring ROM, strength, and function.

2. Operative Management:

Surgical intervention is usually indicated for displaced fractures, significantly impacted fractures, those associated with rotator cuff tears, and fractures causing significant functional impairment. Surgical techniques vary depending on the fracture characteristics and surgeon preference. Common surgical approaches include:

• Open Reduction and Internal Fixation (ORIF): This involves surgical exposure of the fracture site, anatomical reduction of the fracture fragments, and fixation using screws, plates, or a combination thereof. The goal is to restore anatomical alignment and stability, promoting optimal healing.
• Arthroscopic Repair: In selected cases, minimally invasive arthroscopic techniques can be employed to repair smaller avulsion fractures.

Rehabilitation and Recovery

Rehabilitation plays a crucial role in achieving optimal functional outcomes after a greater tubercle fracture. The rehabilitation program is typically initiated soon after surgery or when pain allows, focusing on:

• Pain Management: Managing pain is important to allow participation in the rehabilitation program.
• Range of Motion Exercises: Gentle range of motion exercises are started early to prevent stiffness and improve mobility. These are progressed gradually as tolerated.
• Strengthening Exercises: Strengthening exercises target the rotator cuff muscles and other shoulder muscles to restore strength and stability.
• Functional Exercises: Functional exercises simulate activities of daily living to facilitate a return to normal activities.
• Return to Activities: The return to work and sports activities depends on individual healing progress and fracture type, guided by the surgeon and physical therapist.

Complications

Potential complications associated with greater tubercle fractures include:

• Nonunion: Failure of the fracture to heal.
• Malunion: Healing in an unsatisfactory position, leading to functional limitations.
• Rotator Cuff Tear: Associated rotator cuff tears are common, requiring concomitant surgical repair.
• Avascular Necrosis: Loss of blood supply to the greater tubercle can result in bone death.
• Infection: Infection at the fracture site is a potential risk, particularly after surgical intervention.
• Stiffness: Shoulder stiffness and loss of ROM are frequent complications if rehabilitation is inadequate.

Prognosis

The prognosis for greater tubercle fractures is generally good, particularly with appropriate treatment and diligent rehabilitation. Most patients regain satisfactory shoulder function, although the time to full recovery can vary depending on the fracture pattern, treatment approach, and individual patient factors.

Conclusion

Fractures of the greater tubercle of the humerus represent a challenging clinical entity requiring accurate diagnosis and individualized treatment planning. A multidisciplinary approach involving orthopedic surgeons, radiologists, and physical therapists is crucial for achieving optimal outcomes. Understanding the various aspects of this fracture, from the mechanism of injury to post-operative rehabilitation, is essential for healthcare professionals involved in the management of these injuries. The focus should always be on restoring anatomical alignment, promoting fracture healing, and achieving functional recovery. Early diagnosis and tailored treatment significantly impact patient outcomes, enabling a swift and safe return to their pre-injury activity levels. Early mobilization and a well-structured rehabilitation program are fundamental to successful recovery and the prevention of long-term complications.