Proximal Humerus Fractures: Essential Etiology, Diagnosis, and Treatment

Proximal Humerus Fractures: Essential Etiology, Diagnosis, and Treatment

Introduction & Epidemiology

Proximal humerus fractures represent a significant orthopedic challenge due to their prevalence, anatomical complexity, and potential for functional impairment. These fractures account for 4-6% of all fractures in adults, making them the third most common fracture, trailing only distal radius and hip fractures. The epidemiology demonstrates a bimodal distribution: predominantly in older individuals with osteoporotic bone following low-energy falls, and less commonly in younger patients sustaining high-energy trauma.

In the geriatric population, incidence rates are notably higher, with a marked female predominance, reflecting the greater prevalence of postmenopausal osteoporosis. Studies indicate that the incidence of proximal humerus fractures escalates significantly after the fifth decade of life, peaking in patients over 70 years old. With an aging global demographic, the societal burden of these injuries, encompassing direct medical costs, rehabilitation, and long-term functional deficits, is projected to increase substantially. Understanding the demographic factors, such as age, gender, bone mineral density, and comorbidities, is critical for both preventive strategies and prognostic considerations. While low-energy falls on an outstretched hand are the most common mechanism in the elderly, high-energy trauma mechanisms, such as motor vehicle accidents or falls from height, are typically responsible for more severe, comminuted fracture patterns in younger, often healthier, individuals. The latter group presents different management challenges, including higher rates of associated soft tissue and neurovascular injuries.

Surgical Anatomy & Biomechanics

A thorough understanding of the surgical anatomy and biomechanics of the proximal humerus is paramount for accurate diagnosis, appropriate classification, and effective management of these fractures.

Surgical Anatomy

The proximal humerus comprises the humeral head, anatomical neck, surgical neck, and the greater and lesser tuberosities.
* Humeral Head: Articulates with the glenoid fossa. Its blood supply is critical for viability. The primary arterial supply to the humeral head is derived from the anterior and posterior humeral circumflex arteries, which are branches of the axillary artery. The ascending branch of the anterior humeral circumflex artery (AHCA) , particularly its arcuate branch, is the predominant source, contributing approximately two-thirds of the blood supply to the epiphysis. This vessel ascends in the bicipital groove and sends numerous branches into the cancellous bone. The posterior humeral circumflex artery (PHCA) provides additional contributions, particularly to the posterior aspect of the head and tuberosities. There is a vulnerable watershed area between the anterior and posterior circulations. Disruption of the AHCA, especially in multi-part fractures involving the surgical neck and tuberosities, significantly elevates the risk of avascular necrosis (AVN) of the humeral head.
* Anatomical Neck: The demarcation between the humeral head and the tuberosities. Fractures here typically involve the articular cartilage and carry a high risk of AVN.
* Surgical Neck: The narrow region distal to the tuberosities, a common site for fracture.
* Greater Tuberosity: The lateral prominence, serving as the insertion site for the supraspinatus, infraspinatus, and teres minor tendons (SIT muscles). Displacement of this fragment is primarily driven by the superior and posterior pull of these muscles.
* Lesser Tuberosity: The medial prominence, serving as the insertion site for the subscapularis tendon. Its displacement is predominantly medial and anterior.
* Rotator Cuff: The tendons of the supraspinatus, infraspinatus, teres minor, and subscapularis are critical in maintaining shoulder stability and producing motion. In proximal humerus fractures, these tendons often remain attached to their respective tuberosity fragments, exerting significant deforming forces. For example, the supraspinatus pulls the greater tuberosity superiorly, while the subscapularis pulls the lesser tuberosity medially. The pectoralis major, inserting on the bicipital groove, can cause medial displacement of the humeral shaft.
* Neurovascular Structures: The axillary nerve, a branch of the posterior cord of the brachial plexus, is particularly vulnerable. It courses inferior to the humeral head and then posteriorly, traversing the quadrangular space (bounded by the teres minor superiorly, teres major inferiorly, surgical neck of the humerus laterally, and long head of the triceps medially) before innervating the deltoid and teres minor. Iatrogenic injury during surgical exposure or fixation is a significant concern. The brachial plexus, axillary artery, and axillary vein are also at risk, especially in high-energy trauma or fracture-dislocations.

Biomechanics

The stability and displacement patterns of proximal humerus fractures are governed by bone quality, the mechanism of injury, and the deforming forces of the surrounding musculature.
* Bone Quality: In osteoporotic bone, the cancellous architecture is compromised, leading to reduced bone mineral density and increased susceptibility to fracture with low-energy trauma. This also affects the ability to achieve stable screw purchase for internal fixation, increasing the risk of screw cutout or loss of reduction.
* Deforming Forces: The rotator cuff muscles exert powerful and directional forces on the tuberosities and, consequently, on the humeral head fragments. The pectoralis major muscle exerts a strong adduction force on the humeral shaft. These forces contribute to characteristic displacement patterns based on the fracture lines (e.g., varus angulation of the head, medial displacement of the shaft).
* Fracture Classification (Neer Classification): The Neer classification system categorizes fractures based on the displacement of four major segments: the humeral head, greater tuberosity, lesser tuberosity, and humeral shaft. A "part" is considered displaced if there is >1 cm of displacement or >45 degrees of angulation relative to its anatomical position.
* One-part: All fragments are minimally displaced.
* Two-part: One fragment is significantly displaced relative to the others (e.g., surgical neck fracture, greater tuberosity fracture).
* Three-part: Two fragments are displaced relative to the third (e.g., surgical neck with displaced greater tuberosity).
* Four-part: All four fragments are displaced. This pattern carries the highest risk of AVN.
* AO/OTA Classification: A more comprehensive and detailed system based on fracture location (proximal, diaphyseal, distal) and severity (simple, wedge, complex). While providing greater detail, it can have lower inter-observer reliability compared to Neer.

Indications & Contraindications

The decision-making process for managing proximal humerus fractures is complex, weighing patient-specific factors (age, activity level, comorbidities, bone quality) against fracture characteristics (displacement, comminution, articular involvement, vascularity).

Non-Operative Management Indications

Non-operative management remains the cornerstone for a significant proportion of proximal humerus fractures, particularly those that are stable or minimally displaced.
* Minimally Displaced or Stable Fractures:
* One-part fractures (Neer Type I) are almost universally treated non-operatively, regardless of angulation.
* Two-part surgical neck fractures with acceptable angulation (<45 degrees varus/valgus, <1 cm translation).
* Impacted surgical neck fractures.
* Certain two-part greater tuberosity fractures with <5 mm displacement (though 5mm displacement is often cited as a threshold for impingement).
* Low Functional Demand Patients: Elderly, sedentary individuals with significant comorbidities where the risks of surgery outweigh the potential benefits of improved anatomical reduction.
* Severe Comorbidities: Patients with medical conditions precluding safe anesthesia and surgery.
* Poor Bone Quality: Extremely osteoporotic bone where stable internal fixation is unlikely to be achieved.

Operative Management Indications

Operative intervention aims to restore anatomical alignment, provide stable fixation, and facilitate early rehabilitation to optimize functional outcomes.
* Displaced Surgical Neck Fractures:
* Angulation >45 degrees (varus or valgus).
* Translation >1 cm.
* Significant shortening of the humeral shaft.
* Irreducible closed fracture (soft tissue interposition).
* Displaced Anatomical Neck Fractures: High risk of AVN, often managed with arthroplasty, especially in the elderly.
* Displaced Tuberosity Fractures:
* Greater tuberosity displacement >5 mm (often considered >3 mm for younger, active patients) leading to impingement or rotator cuff dysfunction.
* Lesser tuberosity displacement causing subscapularis dysfunction.
* Associated rotator cuff tear requiring repair.
* Three-Part and Four-Part Fractures: These complex patterns inherently involve significant displacement and a high risk of AVN, often requiring open reduction and internal fixation (ORIF) or arthroplasty.
* Fracture-Dislocations: Any displaced fracture associated with glenohumeral dislocation.
* Open Fractures: Require urgent surgical debridement and stabilization.
* Vascular Injury: Associated arterial injury requiring surgical repair.
* Nerve Impingement: Rare but possible, requiring exploration.
* Young, Active Patients: Higher functional demands and lower risk of osteoporosis typically favor anatomical reduction and stable fixation.

Contraindications

• Absolute Contraindications:
  • Active systemic or local infection.
  • Severe soft tissue compromise (e.g., extensive skin necrosis, open wound with gross contamination) precluding safe wound closure.
  • Inability to tolerate anesthesia due to critical medical comorbidities.
  • Irreversible neurological deficit impacting upper extremity function pre-injury.
• Relative Contraindications:
  • Extreme osteoporosis rendering stable fixation impossible.
  • Chronic unreduced dislocation (typically >3 weeks post-injury) where open reduction carries high risks of nerve injury or avascular necrosis.
  • Poor patient compliance with post-operative rehabilitation.

Operative vs. Non-Operative Indications

Pre-Operative Planning & Patient Positioning

Meticulous pre-operative planning is essential to anticipate potential challenges and optimize surgical outcomes.

Pre-Operative Assessment & Imaging

1. Clinical Evaluation: Thorough history and physical examination, including assessment of skin integrity, neurovascular status (deltoid sensation, motor function of axillary nerve, radial, median, ulnar nerves; radial and ulnar pulses), and evaluation for open wounds. Documentation of pre-existing shoulder pathology is crucial.
2. Radiographic Series:
   • True Anteroposterior (AP) view: With the arm in slight external rotation (neutral rotation), perpendicular to the scapula.
   • Scapular Y view: To assess glenohumeral alignment and displacement relative to the glenoid, particularly useful for fracture-dislocations.
   • Axillary view: Provides crucial information about anteroposterior displacement and glenoid involvement. Often difficult to obtain in acute, painful fractures; a Velpeau axillary view (prone, tube angled cephalad) or a trans-scapular lateral view can be attempted.
3. Computed Tomography (CT) Scan: Indicated for most complex proximal humerus fractures.
   • 3D reconstructions: invaluable for visualizing fracture morphology, comminution, articular involvement, and precise fragment displacement.
   • Identification of intra-articular fragments and glenoid rim fractures.
   • Pre-operative templating for implant size and trajectory.
4. Magnetic Resonance Imaging (MRI): Rarely indicated acutely. May be useful for suspected rotator cuff tears in non-displaced or minimally displaced fractures, or to assess humeral head vascularity in equivocal cases, though this is not a routine indication.
5. Classification: Consistent application of a classification system (e.g., Neer, AO/OTA) aids communication and guides treatment decisions.

Patient Positioning

• Anesthesia: General anesthesia is standard. A regional interscalene block can provide excellent post-operative analgesia.
• Positioning:
  • Beach Chair Position: Most common for ORIF and arthroplasty. The patient is semi-recumbent, with the torso elevated 30-70 degrees. The head is secured to prevent excessive neck extension. The ipsilateral arm is draped free to allow full range of motion. This position provides good access to the anterior shoulder, excellent visualization, and allows gravity to assist in reduction. It also facilitates easy fluoroscopy access from various angles.
  • Supine Position: On a radiolucent table with a shoulder bolster for complex cases requiring extensive traction or specific arthroplasty setups. The arm can be placed on a hand table or traction tower. This may be preferred for complex multi-trauma patients.
• Fluoroscopy: Essential for all operative cases to confirm reduction and implant placement. The C-arm must have unimpeded access to obtain true AP, lateral (Y-view), and axillary views of the proximal humerus.
• Draping: Standard sterile orthopedic draping of the shoulder and entire extremity, allowing full manipulation of the arm.

Instrumentation & Implants

• Open Reduction Internal Fixation (ORIF):
  • Locking Plates: Modern fixed-angle locking plates (e.g., PHILOS plate – Proximal Humerus Internal Locking System) are the most common fixation device. They provide angular stability independent of bone quality. Various lengths and designs are available.
  • Screws: Locking and non-locking cortical/cancellous screws.
  • Sutures: High-strength non-absorbable sutures for tuberosity reattachment and augmentation of plate fixation, especially for rotator cuff repair.
  • K-wires, Reduction Clamps: For temporary fixation and fragment manipulation.
  • Bone Graft: Autograft (iliac crest) or allograft (fibula strut graft) may be considered for medial column support or significant bone loss, particularly in osteoporotic patients.
• Intramedullary Nailing: Less commonly used for highly comminuted fractures due to potential for hardware impingement and difficulty controlling head fragment rotation.
• Arthroplasty:
  • Hemiarthroplasty: Replacement of the humeral head only.
  • Reverse Total Shoulder Arthroplasty (RTSA): Replacement of both humeral head and glenoid, with reversal of the ball-and-socket configuration. Increasingly favored for complex fractures in the elderly with poor bone quality or rotator cuff deficiency.
  • Trial Implants: For arthroplasty cases to determine appropriate stem and head size, offset.

Detailed Surgical Approach / Technique

The choice of surgical approach and technique depends on the fracture pattern, patient factors, and surgeon preference. The deltopectoral approach is the workhorse for most proximal humerus fracture fixation.

Deltopectoral Approach (ORIF with Locking Plate)

1. Incision: A curvilinear incision approximately 10-15 cm in length, beginning just lateral to the coracoid process, extending distally along the deltopectoral groove.
2. Superficial Dissection: Identify the deltopectoral groove, which lies between the deltoid muscle (laterally) and the pectoralis major muscle (medially). The cephalic vein typically runs within this groove. This vein should be carefully identified and retracted medially with the pectoralis major or laterally with the deltoid, or ligated if necessary (though generally avoided due to risk of arm swelling).
3. Deep Dissection:
   • Retract the deltoid muscle laterally and the pectoralis major medially.
   • Incise the clavipectoral fascia, exposing the conjoined tendon (coracobrachialis and short head of biceps) and the subscapularis muscle.
   • The internervous plane for this approach is between the axillary nerve (which innervates the deltoid and is lateral) and the pectoral nerves (which innervate the pectoralis major and are medial). Care must be taken to protect the axillary nerve, which typically courses approximately 5-7 cm distal to the acromion, wrapping around the surgical neck.
4. Exposure of Fracture: The subdeltoid bursa is incised to expose the proximal humerus and fracture fragments. The fracture hematoma is carefully evacuated to visualize the fragments. The tuberosities, often attached to their rotator cuff tendons, should be identified and tagged with high-strength sutures for ease of manipulation and reattachment. Identify the bicipital groove and long head of the biceps tendon.

Reduction and Fixation (ORIF)

1. Initial Reduction: Gentle longitudinal traction and manipulation of the arm are applied to disimpact and reduce the fracture. Temporary K-wires or joy-sticks (screws inserted into fragments to facilitate manipulation) can be used to control the humeral head, tuberosities, and shaft. Restoration of the medial calcar anatomy is crucial for stability.
2. Fragment Reduction:
   • Humeral Head: The head fragment is usually reduced first, often using gentle traction, external rotation, and direct manipulation. Its position relative to the glenoid and bicipital groove is key.
   • Tuberosities: The greater and lesser tuberosities are then reduced to the humeral head fragment. The sutures previously placed in the rotator cuff tendons can be used to pull these fragments into anatomical position. The rotator cuff integrity should be assessed and repaired if compromised.
   • Shaft: The humeral shaft is then aligned with the humeral head and tuberosity complex.
3. Temporary Fixation: Once reduced, fragments are held with K-wires.
4. Plate Application (e.g., PHILOS Plate):
   • The locking plate is contoured slightly, if necessary, to fit the lateral aspect of the proximal humerus.
   • The plate is positioned approximately 5-8 mm distal to the superior-most aspect of the greater tuberosity, aligned with the bicipital groove. This position minimizes impingement with the acromion and ensures optimal screw trajectory into the humeral head.
   • The plate is secured to the humeral shaft first with a temporary clamp, then with at least two cortical screws, ensuring proper rotation and length.
   • Humeral Head Screws: Locking screws are then inserted into the humeral head. These screws are designed to provide angular stability. Careful attention to screw length is critical to avoid articular penetration. Multiple screws (typically 5-7) are used, aiming for a divergent pattern to maximize purchase, particularly important in osteoporotic bone. The goal is to create a "calcar cage" of screws to support the inferomedial aspect of the humeral head.
   • Calcar Support: Achieving medial calcar support is paramount for stability and to prevent varus collapse and screw cutout. This can be achieved through anatomical reduction, placement of specific calcar screws, or sometimes with the use of an allograft fibular strut.
5. Suture Augmentation: High-strength sutures are passed through the rotator cuff tendons (subscapularis, supraspinatus) and around the plate, then tied, to provide additional compression of the tuberosities to the plate and humeral head, enhancing fixation, especially in osteoporotic bone.
6. Intramedullary Nailing: Less common for complex fractures due to inability to control head fragments. Typically reserved for some 2-part surgical neck fractures or pathological fractures. Antegrade insertion from the greater tuberosity.
7. Arthroplasty (Hemiarthroplasty/RTSA):
   • Indicated for unsalvageable fractures (severe comminution, high AVN risk, elderly patients with poor bone quality).
   • Hemiarthroplasty: The humeral head is resected, and a prosthetic stem and head are implanted. The crucial step is the meticulous reattachment of the tuberosities around the prosthetic head to restore rotator cuff function.
   • Reverse Total Shoulder Arthroplasty (RTSA): The glenoid is replaced with a glenosphere, and the humeral component consists of a stem with a concave polyethylene liner. This design bypasses a deficient rotator cuff by shifting the center of rotation, making it highly effective for complex fractures in elderly patients, especially those with pre-existing rotator cuff arthropathy or very poor bone quality where tuberosity healing is unlikely. The goal is still to incorporate the tuberosities around the implant for better function and cosmesis, though healing is less critical than in hemiarthroplasty.
8. Final Assessment: Thorough fluoroscopic evaluation of reduction, screw lengths, and implant position in all planes. Check for impingement. Assess range of motion to ensure no undue tension on soft tissues.
9. Closure: Layered closure, starting with repair of the deltopectoral fascia. A drain may be placed in the subdeltoid space if significant oozing is anticipated. Standard skin closure.

Complications & Management

Proximal humerus fracture management is associated with a notable rate of complications, requiring prompt recognition and appropriate salvage strategies.

Post-Operative Rehabilitation Protocols

Post-operative rehabilitation is crucial for optimizing functional outcomes following surgical management of proximal humerus fractures. Protocols are tailored based on the stability of fixation, bone quality, concomitant injuries (e.g., rotator cuff repair), and patient compliance. The overarching goal is to balance protection of the surgical repair with the prevention of stiffness.

General Principles

• Pain Management: Adequate pain control is essential to facilitate patient participation in therapy.
• Immobilization: Sling use (e.g., UltraSling with abduction pillow) is common for protection, especially for the initial 4-6 weeks.
• Gradual Progression: Rehabilitation progresses through distinct phases, from passive to active, then resisted exercises, based on biological healing and implant stability.
• Surgeon-Therapist Communication: Close collaboration between the surgeon and physical therapist is critical to adjust protocols as needed.

Phase I: Immediate Post-Operative (0-6 Weeks) - Protection & Early Motion

• Goals: Control pain and swelling, protect surgical repair, prevent stiffness of uninvolved joints, initiate gentle passive range of motion (PROM) for the shoulder within protected arcs.
• Immobilization:
  • Sling continuously, removed only for hygiene and exercises.
  • Abduction pillow may be used to protect tuberosity repairs or for comfort.
• Exercises:
  • Pendulum exercises: Gentle, gravity-assisted swings of the arm while leaning forward, to encourage passive motion.
  • Elbow, wrist, hand active range of motion (AROM): To prevent stiffness in these joints.
  • Passive Shoulder ROM (as tolerated and approved by surgeon):
    • Forward Flexion: Supine, therapist assists to 0-90 degrees (or less, depending on stability).
    • External Rotation: Supine, arm adducted to body, therapist assists to 0-30 degrees (or less if tuberosity repair is tenuous).
    • Internal Rotation: Hand-to-stomach/back exercises.
  • Scapular stabilization exercises: Gentle isometric contractions.
• Restrictions: No active shoulder flexion, abduction, or external rotation. No lifting, pushing, pulling. Avoid sustained positioning that stresses the repair.

Phase II: Early Mobility & Assisted Strengthening (6-12 Weeks) - Gradual Increase in Motion

• Goals: Restore full passive and assisted active range of motion, initiate gentle isometric strengthening.
• Immobilization: Wean from sling, often worn for comfort or in crowded environments.
• Exercises:
  • Progressive PROM: Continue to advance PROM to achieve near full range in all planes.
  • Assisted Active Range of Motion (AAROM):
    • Wand exercises: Using a stick to assist shoulder flexion, abduction, external/internal rotation.
    • Pulley exercises: To assist with flexion and abduction.
  • Gentle Isometric Exercises: Light isometric contractions for rotator cuff and deltoid at various angles, holding for short durations.
  • Gravity-eliminated plane exercises: Initiate AROM in supine position for easier movement.
• Restrictions: No unassisted lifting above the shoulder, pushing, or pulling. Avoid heavy resistance.

Phase III: Strengthening & Functional Recovery (12 Weeks - 6 Months) - Progressive Strengthening

• Goals: Progress to full active range of motion, significantly increase strength, improve endurance, and prepare for return to functional activities.
• Exercises:
  • Active Range of Motion (AROM): Progress towards full unassisted AROM.
  • Progressive Strengthening:
    • Resistance band exercises for rotator cuff (internal/external rotation), deltoid (flexion, abduction), and scapular stabilizers.
    • Light weights for shoulder muscles.
    • Proprioceptive training.
    • Wall slides, seated rows, upright rows, lateral raises (gradual progression).
  • Core and Postural Strengthening: To support overall upper body mechanics.
• Restrictions: Continue to avoid heavy lifting and high-impact activities. Progress resistance cautiously.

Phase IV: Advanced Strengthening & Return to Activity (6 Months Onwards) - Sport-Specific Training

• Goals: Achieve maximal strength, endurance, and power. Return to sport-specific or work-specific activities.
• Exercises:
  • Advanced Strengthening: Heavier weights, plyometrics (if appropriate), sport-specific drills.
  • Endurance Training: Repetitive low-resistance exercises.
  • High-Impact Activities: Gradual reintroduction.
• Return to Activity: Judgement based on strength, pain levels, and functional capacity. Full return to contact sports or heavy labor may take 9-12 months, or more, depending on the severity of the injury and the demands of the activity.

Summary of Key Literature / Guidelines

The management of proximal humerus fractures has evolved significantly, driven by advancements in surgical techniques, implant technology, and a growing body of evidence. However, consensus on optimal treatment strategies, particularly for complex patterns in the elderly, remains elusive.

Classification Systems

• Neer Classification: Remains the most widely used clinical system due to its simplicity and direct correlation with prognosis and treatment implications, especially regarding the risk of AVN. However, its inter-observer reliability has been criticized.
• AO/OTA Classification: Offers a more detailed and mechanistic description of fractures, useful for research and detailed surgical planning. Its complexity can lead to lower inter-observer reliability in clinical settings.

Non-Operative vs. Operative Management

• For one-part and minimally displaced two-part fractures , non-operative management remains the gold standard, demonstrating equivalent or superior outcomes compared to surgery with fewer complications.
• The decision for displaced two-part, three-part, and some four-part fractures in the elderly is more controversial. The PROximal Fracture of the Humerus: a multicentre randomised controlled Trial (PROPHET) , published in The Lancet (2015), compared surgery (ORIF or arthroplasty) with non-surgical care for displaced proximal humerus fractures in older adults. It found no significant difference in functional outcomes (Oxford Shoulder Score) at 2 years, but higher complication rates in the surgical group. This study has fueled conservative approaches for many elderly patients. However, limitations include broad patient selection, variable surgical techniques, and potential lack of power to detect subtle differences in specific subgroups. Subsequent meta-analyses have largely supported these findings, highlighting the importance of patient selection.
• Younger, active patients with displaced fractures are generally managed operatively to restore anatomical alignment and function.

Surgical Modalities and Trends

• Open Reduction Internal Fixation (ORIF) with Locking Plates:
  • Fixed-angle locking plates (e.g., PHILOS) are the current standard for ORIF, providing angular stability independent of bone quality. They have improved outcomes compared to earlier non-locking plates, particularly in osteoporotic bone.
  • Key Literature: Meta-analyses show improved reduction and fixation stability, but complication rates remain high (10-30%), especially AVN, screw cutout, and nonunion in osteoporotic patients.
  • Medial Column Support: Recent emphasis on restoring medial column support (e.g., calcar screws, fibular strut grafts) is crucial to prevent varus collapse and screw cutout, particularly in osteoporotic bone. Studies by Gardner et al. have highlighted the biomechanical importance of these constructs.
• Intramedullary Nailing:
  • Less invasive, but challenges remain in controlling the humeral head fragment rotation and potential for rotator cuff impingement. Generally reserved for specific 2-part surgical neck fractures without significant tuberosity involvement, or pathological fractures.
• Arthroplasty:
  • Hemiarthroplasty (HA): Historically used for unsalvageable 3- and 4-part fractures, especially in the elderly with high AVN risk. However, outcomes are often unpredictable, heavily dependent on tuberosity healing, which can be challenging in osteoporotic bone. Pain and functional limitations are common.
  • Reverse Total Shoulder Arthroplasty (RTSA):
    • Key Literature: Increasingly recognized as the preferred treatment for complex proximal humerus fractures in elderly patients (typically >70-75 years old), particularly those with poor bone quality, rotator cuff deficiency, or significant comminution where tuberosity healing is unlikely. Studies show superior functional outcomes, better pain relief, and more predictable results compared to HA in this population. It effectively bypasses rotator cuff dysfunction.
    • Indications for RTSA in Fractures: Four-part fractures, fracture-dislocations, three-part fractures with high AVN risk or poor bone quality, failed ORIF, elderly patients with pre-existing rotator cuff arthropathy or pseudoparalysis.
  • Trends: A clear shift towards RTSA for complex fractures in the elderly, offering a more reliable solution with predictable outcomes.

Rehabilitation Guidelines

• Early controlled passive motion is generally advocated to prevent stiffness, but progression must be guided by fracture stability and fixation strength.
• The balance between protection and early motion remains a critical aspect, with individualized protocols being key.

Future Directions

• Development of patient-specific implants and advanced biomaterials for improved fixation in osteoporotic bone.
• Further refinement of biological fixation techniques to enhance tuberosity healing.
• Continued research, including large-scale randomized controlled trials, to define clearer indications for specific surgical interventions, especially comparing modern plating techniques with RTSA in defined patient subgroups.
• Enhanced pre-operative planning tools, including advanced 3D imaging and virtual surgical planning.