Humeral Shaft Fracture: Overview and Evidence Summary

Condition Overview

A humeral shaft fracture refers to a break occurring along the long, central portion of the upper arm bone—between the surgical neck proximally and the supracondylar region distally. These fractures vary widely in presentation: they may be simple, spiral injuries from a fall; oblique or transverse breaks from direct trauma; or complex comminuted fractures resulting from high-energy collisions. Because the humerus is surrounded by substantial muscle mass, deformity may be masked, but swelling, bruising, and severe functional limitation are almost always present.

One defining feature of humeral shaft fractures is the involvement of the radial nerve, which spirals closely around the humerus in the radial groove. Radial nerve palsy, presenting as wrist drop, finger extension weakness, or dorsal hand numbness, occurs in a significant percentage of cases. Fortunately, most radial nerve palsies associated with closed fractures recover spontaneously, but their presence adds complexity to management.

Unlike many long-bone fractures, humeral shaft fractures frequently do not require surgery. The humerus heals well with functional bracing due to the excellent blood supply and the ability of surrounding muscles to maintain alignment through compression. In fact, functional bracing has some of the highest union rates of any fracture treatment. This stands in contrast to patient expectations, as many imagine that long-bone fractures must be fixed surgically. Clear reassurance and education are often crucial in early management.

Pain is severe initially but typically decreases over weeks as callus forms. However, the functional cost of immobilization is significant: shoulder and elbow stiffness can develop quickly, making rehabilitation essential. Early, protected motion of adjacent joints prevents secondary complications, while gradual loading helps restore strength and normalize limb use.

Recovery is often lengthy—many patients require several months before the arm feels reliably strong. Even after full bony union, fatigue, weakness, and movement apprehension can linger without structured rehabilitation. With appropriate care, however, most individuals regain excellent function, even after complex fracture patterns.

Summary of Current Evidence for Humeral Shaft Fracture

Evidence-Based Management Discussion

Mechanics of Injury and Early Considerations

The humeral shaft is subjected to enormous rotational and bending forces during daily activity. When trauma occurs—whether from a fall onto an outstretched hand, a twisting force during sport, or a direct blow—the bone fails according to how the force was applied. Spiral fractures often arise from rotational mechanisms, while transverse fractures reflect direct impact. Comminuted fractures may indicate high-velocity energy or significant soft tissue involvement.

Because of the humerus’s close relationship with the radial nerve, careful neurological assessment is essential at first contact. Patients may initially be unaware of nerve involvement due to pain or shock, so deliberate testing of wrist and finger extension is mandatory. Even in the presence of nerve palsy, non-operative treatment often proceeds unless open fracture or nerve entrapment demands exploration.

The shoulder and elbow are both immediately affected by guarding and swelling. Stiffness develops rapidly, which is why early guided movement of adjacent joints is critical—even while the fracture itself remains protected.

Functional Bracing and Why It Works

Functional bracing is a hallmark of humeral shaft fracture treatment. Unlike rigid immobilization, functional bracing:

• allows controlled micro-movement at the fracture site

• uses surrounding muscle contractions to maintain alignment

• permits early use of the limb

• reduces the risk of shoulder and elbow contracture

As swelling decreases during the first 7–10 days, the brace fits more snugly, and the fracture begins to stabilize through callus formation. During this period, patient education is vital—they must understand that gentle arm motion is beneficial, not harmful, and that early mobility supports healing.

Pain typically decreases as stability improves. By 6–8 weeks, callus is usually visible radiographically, and more functional loading becomes appropriate.

Clinical Presentation: Pain, Weakness, and Functional Disruption

The early days are dominated by pain and guarding. Patients cradle the arm, avoid elbow extension, and may support the wrist with the opposite hand. Bruising often travels down the arm into the forearm and chest wall due to gravity and soft tissue swelling.

Functional limitations include:

• Difficulty dressing or grooming

• Inability to lie on the injured side

• Loss of confidence in lifting or reaching

• Temporary “one-handed living,” particularly in older adults

If radial nerve palsy is present, patients additionally struggle with wrist extension and grip strength.

Exercise Therapy

Rehabilitation must follow the biology of bone healing while ensuring adjacent joints remain functional.

Phase 1: Early Mobility and Pain Control (Weeks 0–3)

During the acute phase—typically while in a sling or splint prior to bracing—movement should be pain-free and respect fracture stability.

Focus includes:

• Elbow flexion/extension

• Wrist and finger mobility

• Pendulum exercises (gentle)

• Posture and relaxation strategies to reduce upper-trapezius dominance

A surprising amount of shoulder stiffness can accumulate even within the first two weeks; early small-arc movement prevents long-term deficits.

Phase 2: Functional Bracing and Controlled Motion (Weeks 2–6)

As the brace is applied and callus begins forming:

• Active-assisted shoulder movement begins

• Elbow ROM becomes a priority

• External rotation within comfortable limits helps prevent capsular contracture

• Gentle isometric strengthening maintains muscle engagement

Patients must avoid lifting weight or pushing/pulling forces that could disrupt the fracture, but movement without resistance is strongly encouraged.

Phase 3: Active Strengthening (Weeks 6–12)

Once early union is confirmed:

• Rotator cuff and deltoid strengthening begins

• Scapular control training restores normal kinematics

• Light functional tasks (e.g., table wiping, reaching patterns) are introduced

• Resistance is added gradually, avoiding heavy loads until radiographic consolidation

Radial nerve involvement, if present, is addressed through motor retraining, splinting, and progressive strengthening as recovery begins.

Phase 4: Functional Integration and Return to Full Activity (3–6+ Months)

In the late phase:

• Strength is restored across all planes

• Proprioception and endurance training support everyday use

• Sport- or job-specific drills are incorporated

• Patients work toward lifting, carrying, pushing, and pulling confidently

Recovery may feel slow despite radiographic healing, as the shoulder and elbow must relearn coordinated movement after prolonged protection.

Manual Therapy

Manual therapy becomes appropriate once fracture stability is secure and pain is controlled, typically after several weeks. At this stage, therapists address:

• Shoulder capsular stiffness

• Elbow extension restrictions

• Soft tissue tightness in deltoid, biceps, pectorals, and upper trapezius

• Scapular mobility deficits

Manual therapy is particularly valuable for preventing adhesive capsulitis—a risk when shoulder motion is limited for prolonged periods.

Pain Management and Bone Health

Effective pain management includes analgesics, NSAIDs (used judiciously due to potential effects on bone healing), and cryotherapy during early recovery.

Because many humeral shaft fractures in older adults stem from osteoporosis, evaluation of bone health is essential. Vitamin D supplementation, calcium intake optimization, lifestyle modifications, and bisphosphonate therapy may all reduce risk of future fractures.

Surgical Considerations

Although conservative treatment is successful in most cases, surgery becomes necessary when:

• Fractures are significantly displaced or angulated

• There is an open fracture

• Radial nerve palsy occurs with specific fracture patterns (e.g., Holstein–Lewis fractures)

• Vascular injury is present

• Conservative care fails to achieve union

• The patient has multiple injuries requiring early mobilization

Surgical options include intramedullary nails, plates and screws, or—rarely—external fixation. Even after surgery, rehabilitation remains essential for regaining full function.

Clinical Considerations for Therapists

Therapists must navigate a delicate balance:

• Too little movement leads to stiffness

• Too much movement jeopardizes fracture healing

Clear communication with the medical team regarding healing stage, radiographic findings, and patient tolerance is essential. Above all, therapists must build patient confidence—many individuals fear using the arm after a fracture, leading to unnecessary guarding long after healing is well underway.

References

Sarmiento, A., et al. “Functional Bracing for Humeral Shaft Fractures: A Clinical Outcome Review.” Journal of Bone and Joint Surgery, 2000–2020 literature.

Ekholm, R., et al. “Humeral Shaft Fractures: Epidemiology and Trends.” Injury, 2006 and updates.

Shao, Y.-C., et al. “Radial Nerve Palsy Associated with Humeral Shaft Fracture.” Journal of Bone and Joint Surgery, 2005.

Fjalestad, T., et al. “Conservative vs Operative Treatment of Humeral Shaft Fractures.” Clinical Orthopaedics and Related Research, 2012.

Brorson, S., et al. “Rehabilitation After Humeral Fracture: A Clinical Overview.” Physiotherapy Research International, 2018.

Disclaimer

The information in this article is intended for educational purposes and is designed for qualified massage therapists, manual therapists, and rehabilitation professionals. It is not a substitute for medical advice, diagnosis, or treatment. Practitioners must work within their legal scope of practice and regional regulations. Hands-on techniques should only be performed by appropriately trained and licensed individuals. Niel Asher Education is not responsible for any injury, loss, or damage resulting from the use of this content.