01Approach to the Critical Patient/attcp36

Immediate priorities

›High-acuity presentations requiring urgent action

›Open fracture with exposed bone or contaminated wound

›Emergent orthopedic consult

›IV antibiotics within 1 hour (Gustilo I/II: cefazolin; III: add aminoglycoside)

›Tetanus prophylaxis if not up to date

›Vascular injury with absent or diminished distal pulses

›Immediate vascular surgery consult

›Doppler assessment of radial and ulnar pulses

›Expanding hematoma signals arterial injury

›Compartment syndrome

›Pain out of proportion to injury

›Pain with passive finger extension

›Emergent fasciotomy if confirmed

›Polytrauma with humeral shaft fracture

›21% mortality reported in polytrauma context

›ATLS primary survey before extremity assessment

›Head injury and multi-site fractures present in 74% of polytrauma cases

Monitoring and targets

›Neurovascular check cadence

›Baseline prior to any manipulation or splinting

›Repeat after immobilization is applied

›Radial nerve palsy present in ~10% of closed fractures

›Up to 25% in high-energy mechanisms

›Document wrist extension, finger MCP extension, dorsal first web space sensation

›Vascular compromise in <1% of isolated fractures but 52x higher odds when nerve palsy present

›Pain control targets

›Numeric rating scale <= 4 before discharge

02History/hx46

Mechanism and onset

›Mechanism of injury

›Low-energy fall (~60-70% of cases)

›Elderly women predominate

›Fragility fracture consideration

›High-energy trauma

›Motor vehicle crash

›Sports injury or direct blow

›Twisting mechanism

›Pathological fracture risk

›Minimal or no trauma

›Preceding focal pain or weakness in arm

›Symptom characterization

›Acute upper arm pain

›Inability to use the arm

›Swelling and visible deformity

›Crepitus felt or heard at time of injury

Neurological and vascular symptoms

›Radial nerve distribution symptoms

›Wrist drop or inability to extend wrist

›Finger drop at MCP joints

›Numbness or tingling over dorsal first web space

›Ulnar and median nerve symptoms

›Numbness of small finger (ulnar)

›Thumb opposition weakness (median)

›Vascular symptoms

›Cold or pale hand

›Loss of grip or pulsatile sensation

03Physical Exam/exam40

Inspection and palpation

›Upper arm assessment

›Swelling and soft tissue edema

›Deformity and shortening of the arm

›Ecchymosis tracking to elbow and forearm (gravity sign)

›Skin integrity: open wounds, skin tenting, impending open fracture

›Point tenderness over humeral shaft

›Crepitus and abnormal mobility at fracture site

Neurovascular exam

›Radial nerve function (most commonly injured)

›Wrist extension strength

›Finger MCP extension strength

›Sensation over dorsal first web space

›Ulnar nerve function

›Finger abduction and adduction

›Sensation of small finger palmar surface

›Median nerve function

›Thumb opposition

›Index finger flexion

›Sensation of palmar index finger

›Vascular assessment

›Radial pulse presence and quality

›Ulnar pulse presence and quality

›Capillary refill time in fingers

›Hand temperature and color

Associated injury screen

›Shoulder and elbow range of motion

›Intra-articular extension at shoulder or elbow

04Differential Diagnosis/ddx29

Fracture variants and related diagnoses

›Humeral shaft fracture spectrum

›Closed, simple shaft fracture (most common)

›ICD-10 S42.30XA (initial encounter)

›Middle third most common (~48%)

›Open humeral shaft fracture

›ICD-10 S42.30XB (initial encounter, open)

›Occurs in ~2-3% of humeral shaft fractures

›Pathological humeral fracture

›ICD-10 M84.522 (pathological fracture, humerus)

›4-8% of humeral shaft fractures are pathological

›Periprosthetic humeral fracture

›ICD-10 M97.31 (fracture around internal prosthetic right shoulder joint)

›~2.5% of humeral shaft fractures

Mimics requiring exclusion

›Proximal humerus fracture

›Pain and deformity predominantly at shoulder

›Different management pathway

›Humeral stress fracture

›Athletes with throwing mechanics (baseball pitchers)

›No acute trauma, gradual pain onset

›MRI confirms if X-ray negative

›Soft tissue injury without fracture

›Biceps or triceps rupture: no bony abnormality on imaging

›Contusion: point tenderness without crepitus or deformity

›Brachial plexus injury

›Widespread neurologic deficits

›No fracture on imaging

05Laboratory Tests/lt28

Isolated fracture workup

›Standard isolated closed fracture

›Routine labs not required in healthy patients with isolated, closed fracture

›Preoperative labs if surgery planned

›Complete blood count

›Basic metabolic panel

›Coagulation studies

›Type and screen

Pathological fracture workup

›Metabolic and malignancy panel

›Complete blood count with differential

›Anemia suggesting marrow infiltration

›Leukocytosis or pancytopenia

›Comprehensive metabolic panel

›Serum calcium elevation in malignancy and hyperparathyroidism

›Alkaline phosphatase elevation in bone turnover or liver metastases

›Inflammatory markers

›ESR and CRP for myeloma and inflammatory causes

›Serum protein electrophoresis

›M-protein spike diagnostic of myeloma

›PSA in males

›Prostate metastases are a leading cause

›TSH

›Thyroid cancer as metastatic source

Polytrauma labs

›Trauma panel

›Complete blood count for hemorrhage assessment

›Basic metabolic panel for organ function

06Diagnostic Tests/dt71

Scoring Systems

›Fracture classification systems

›AO/OTA Classification

›12A: Simple fractures (transverse, oblique, spiral)

›12B: Wedge fractures

›12C: Complex comminuted fractures

›Guides surgical planning and prognosis

›Gustilo-Anderson Classification for open fractures

›Grade I: wound <1 cm, clean

›Grade II: wound 1-10 cm, moderate contamination

›Grade IIIA: wound >10 cm, adequate soft tissue coverage

›Grade IIIB: periosteal stripping, soft tissue loss

›Grade IIIC: arterial injury requiring repair

›Determines antibiotic regimen and urgency

›Alignment thresholds for nonoperative management

›Acceptable angulation

›<30 degrees varus/valgus in coronal plane

›<20 degrees anterior/posterior in sagittal plane

›Shortening <3 cm generally accepted

›EMG and nerve conduction studies

›Recommended if no radial nerve recovery by 9 weeks

›Distinguishes neuropraxia from axonotmesis and neurotmesis

›Late surgical exploration recommended if no recovery by 6 months

MRI

›MRI indications for humeral shaft fracture

›Pathological fracture evaluation

›Identifies marrow infiltration and soft tissue extension

›Characterizes lesion type (lytic, sclerotic, mixed)

07Disposition/dispo33

Admission indications

›Mandatory admission criteria

›Open fracture requiring operative debridement

›Emergent washout within 6-8 hours for Gustilo IIIB/IIIC

›IV antibiotics initiated in ED

›Vascular injury requiring repair

›Vascular surgery admission

›OR availability required

›Polytrauma with associated injuries

›ICU or monitored bed based on severity

›Compartment syndrome

›Emergent fasciotomy

›Inability to achieve adequate outpatient pain control

›Compartment risk monitoring requirement for high-energy injuries

Discharge criteria

›Outpatient management suitability

›Isolated, closed fracture with intact neurovascular exam

›Adequate pain control with oral multimodal analgesia

›Appropriate immobilization applied and tolerated

›Orthopedic follow-up arranged within 7-10 days

›Patient understands brace care and activity restrictions

›Reliable social support for compliance with nonoperative protocol

Consultation triggers

›Orthopedic surgery

›All humeral shaft fractures require orthopedic follow-up

›Emergent consult for open fractures, vascular injury, floating elbow, compartment syndrome

›Vascular surgery

›Absent or diminished pulses

08Treatment/t78

Initial ED management

›Immobilization

›Coaptation (sugar-tong) splint

›Wraps around elbow and up both sides of humerus

›No significant difference in alignment outcomes vs other splint types

›Posterior long-arm splint alternative

›Acceptable when sugar-tong not feasible

›Sling and swathe as temporizing measure

›Suitable for transport and comfort

›Neurovascular exam documented before and after splinting

›Pain management

›Multimodal analgesia preferred

›Acetaminophen 1000 mg PO every 6-8 hours

›Ibuprofen 400-600 mg PO every 6-8 hours with food

›Ketorolac 15-30 mg IV for severe acute pain

›Opioid use reserved for severe pain not controlled by above

›Oxycodone 5-10 mg PO every 4-6 hours PRN

›Minimize duration and quantity prescribed

›Hematoma block for reduction facilitation

›10-20 mL of 1% lidocaine injected into fracture hematoma

›Ultrasound guidance improves accuracy

Nonoperative management

›Functional bracing (Sarmiento brace)

›Conversion from splint at 7-10 days once swelling subsides

›Union achieved in >89% at approximately 10 weeks

›Nonunion risk 15-25% with bracing

›Acceptable angulation: <30 degrees coronal, <20 degrees sagittal

›Rehabilitation protocol

›Immediate pendulum exercises of shoulder (Day 1)

›Active elbow and hand ROM maintained throughout

›Gradual weight-bearing at 6 weeks

›Full return to activity guided by radiographic union

›Compliance support

›Brace care instruction: cleaning, skin inspection, tightening

›No lifting, pushing, or weight-bearing with affected arm for at least 6 weeks

›Obesity may compromise brace fit and outcomes

Operative management

›Surgical indications

›Open fractures (Gustilo II and III)

›Polytrauma and high-energy injuries

›Vascular injury requiring repair

›Floating elbow (ipsilateral forearm fracture)

›Bilateral humeral fractures

›Pathological fractures

›Failure of nonoperative management (nonunion)

›Patient preference after shared decision-making (especially working-age patients)

›Surgical options

›Open reduction and internal fixation (ORIF) with plate and screws

›Gold standard approach

›Nonunion rate 0.7-6% vs 15-25% with bracing

›Radial nerve exploration at time of ORIF in selected cases

›Minimally invasive plate osteosynthesis (MIPO)

›Lowest complication and nonunion rates in network meta-analysis

›Preserves soft tissue envelope

›Intramedullary nailing

›Suitable for length-unstable fractures

›Higher shoulder morbidity compared to plating

›Long-term outcomes at 12 months similar between surgery and successful bracing

Radial nerve palsy management

›Primary radial nerve palsy (at time of fracture)

›>90% recover spontaneously; observation is standard

›Wrist-extension splint to prevent contracture

›EMG/NCS at 9 weeks if no clinical recovery

›Late surgical exploration if no recovery by 6 months

›Recovery probability data

›If no recovery by 7 months, ~56% probability of recovery by 18 months

›If no recovery by 12 months, probability drops to ~17%

›Secondary (iatrogenic) radial nerve palsy

›Immediate surgical exploration recommended

›Nerve in continuity has better prognosis than transection

Open fracture antibiotic protocol

›Gustilo Grade I and II

›Cefazolin 2 g IV every 8 hours

›Continue for 24 hours post wound closure

›Weight-based dosing: 2 g for patients under 120 kg; 3 g for over 120 kg

›Gustilo Grade III

›Cefazolin 2 g IV plus gentamicin 5-7 mg/kg IV daily

›Continue for 72 hours or until wound closure

›Adjust for renal function

›Add metronidazole 500 mg IV every 8 hours if farm/fecal contamination

›Penicillin allergy alternatives

›Clindamycin 900 mg IV every 8 hours

›Add gentamicin for gram-negative coverage in Grade III

09Special Populations/sp63

Pregnancy

›Pregnancy-specific considerations

›Mechanism

›Falls during pregnancy more common due to shifted center of gravity

›Increased ligamentous laxity may affect splint fit

›Imaging

›Plain radiography with abdominal shielding appropriate when clinically indicated

›CT only when benefits clearly outweigh fetal radiation risks

›MRI preferred over CT for soft tissue or pathological fracture concerns

›Pain management

›Acetaminophen preferred analgesic in pregnancy

›NSAIDs avoid after 30 weeks (risk of premature ductus arteriosus closure)

›Short-term opioid use acceptable with monitoring in first and second trimester

›Neonatal opioid withdrawal syndrome risk with prolonged use

›Antibiotic selection for open fractures

›Cefazolin safe in pregnancy (all trimesters)

›Clindamycin acceptable alternative if penicillin allergy

›Gentamicin use with caution (fetal nephrotoxicity and ototoxicity risk)

›Positioning

›Left lateral decubitus positioning to avoid aortocaval compression

Geriatric

›Geriatric-specific considerations

›Fracture characteristics

›Low-energy falls predominate in elderly women

›Proximal and middle third fractures should be considered fragility fractures

›DEXA scan referral for bone density assessment as outpatient

›Fall evaluation

›Syncope, arrhythmia, or orthostatic hypotension as precipitant

10Background/b56

Epidemiology

›Incidence and burden

›Humeral shaft fractures account for 1-3% of all adult fractures

›Incidence approximately 12-14.5 per 100,000 per year

›Approximately 60,000 ED visits annually in the United States

›Bimodal age distribution

›Low-energy falls in older adults (especially women)

›High-energy trauma in younger patients (especially men)

›Location distribution

›Middle third most common: ~48% of humeral shaft fractures

›Proximal third: ~30%

›Distal third: ~22%

›Complication rates

›Radial nerve palsy: ~10% of closed fractures

›Open fractures: ~2-3%

›Pathological fractures: 4-8%

›Periprosthetic fractures: ~2.5%

›Nonunion with bracing: 15-25%; with surgery: 0.7-6%

›Mortality in polytrauma context: 21%

Pathophysiology

›Fracture mechanics

›Transverse: direct blow perpendicular to shaft

›Oblique or spiral: twisting or rotational force

›Holstein-Lewis fracture: spiral fracture at distal third with high radial nerve palsy risk

›Comminuted: high-energy with multiple fragments

›Pathological: bone weakened by tumor, metabolic disease, or radiation

›Radial nerve vulnerability

›Radial nerve courses through spiral groove of humerus

11Patient Discharge Instructions/pdi32

copy discharge instructions

›Humerus fracture home care instructions

›Keep the splint or brace in place as instructed

›Do not remove, modify, or get the splint wet

›Keep the arm elevated when possible to reduce swelling

›No lifting, carrying, pushing, or pulling with the injured arm for at least 6 weeks

›Pain and medication instructions

›Acetaminophen and ibuprofen as directed for pain control

›If prescribed opioids, take only as needed and do not drive

›Do not drink alcohol while taking opioid medications

›Follow-up instructions

›Orthopedic appointment within 7-10 days is essential

›Repeat X-rays will be taken to confirm the bone is in acceptable position

›At that visit, the splint may be converted to a removable functional brace

›Physical therapy will begin to restore shoulder and elbow movement

›Warning signs to return to the emergency department immediately

›New or worsening numbness, tingling, or weakness in the hand or fingers

›Inability to extend the wrist or fingers (wrist drop)

›Increasing pain not controlled by medications

›Swelling that is rapidly worsening or the skin feels very tight

›Any open sores, wound drainage, or smell from the splint area

›Fever above 38.5 degrees Celsius

›Loss of pulse or color change in the hand (pale, blue, cold)

›Brace or splint becoming very loose with visible new deformity

›Activity and recovery expectations

›Most patients with closed fractures heal over 10-12 weeks

›Full functional recovery may take 3-6 months

›Attend all scheduled physical therapy and follow-up appointments

12References/r39

Guidelines and key sources

›Key clinical trials

›FISH Randomized Clinical Trial (JAMA 2020)

›Surgery vs functional bracing for closed displaced humeral shaft fractures

›No significant difference in functional outcome at 12 months

›Ramo L et al. JAMA. 2020

›HUFF Trial (JAMA Surgery 2025)

›Operative vs nonoperative management of humeral diaphysis fractures

›Oliver WM et al. JAMA Surgery. 2025

›Cochrane Review (2012)

›Surgical vs non-surgical interventions for humeral shaft fractures in adults

›Gosler MW et al. Cochrane Database Syst Rev. 2012

›Systematic reviews and meta-analyses

›Oliver WM et al. JAAOS 2023

›Surgical vs nonsurgical management: meta-analysis of randomized trials

›Van Bergen SH et al. Arch Orthop Trauma Surg 2023

›Systematic review of nonoperative and operative treatment

›Colasanti CA et al. J Orthop Trauma 2024

›Network meta-analysis of individual treatment modalities

›Epidemiology and radial nerve references

›Mattila H et al. J Shoulder Elbow Surg 2023

›Epidemiology of 936 humeral shaft fractures in Finnish trauma center

›Hendrickx LAM et al. Arch Orthop Trauma Surg 2021

›Systematic review of radial nerve palsy in 1758 patients

›Entezari V et al. J Shoulder Elbow Surg 2021

›Predictors of traumatic nerve injury and recovery

›Krijnen NA et al. Clin Orthop Relat Res 2026

›Probability of radial nerve recovery after surgical repair accounting for time since injury

Evidence & Review

Evidence & Review