Overview
Hand Injuries
Quick Reference
Critical Alerts
- Examine tendons against resistance: Partial injuries may have preserved ROM
- Test 2-point discrimination for nerve injury: <5 mm is normal
- Examine throughout range of motion: Tendon injuries at different positions
- High-pressure injection injuries are emergencies: Surgical exploration
- Fight bites (clenched fist) are high-risk: Human bite to MCP joint
- Flexor tendon injuries need hand surgery referral
Key Structures to Assess
| Structure | Test |
|---|---|
| Flexor digitorum profundus (FDP) | Flex DIP while holding PIP |
| Flexor digitorum superficialis (FDS) | Flex PIP while holding other fingers extended |
| Extensor tendon | Extend finger against resistance |
| Digital nerves | 2-point discrimination |
| Vascular | Capillary refill, Allen test |
Emergency Treatments
| Injury | Treatment |
|---|---|
| Simple laceration | Irrigation, repair, tetanus |
| Tendon laceration | Refer hand surgery |
| Nail bed injury | Repair, trephination if subungual hematoma |
| Fracture | Splint, refer if displaced/rotational |
| High-pressure injection | Emergent surgical exploration |
| Fight bite | Irrigation, antibiotics, consider exploration |
Definition
Overview
Hand injuries encompass a wide range of conditions including lacerations, fractures, tendon injuries, nerve injuries, and vascular injuries. Careful examination of tendons, nerves, and vessels is essential. Missed flexor tendon or nerve injuries can result in significant disability. Many injuries require hand surgery referral.
Classification
By Structure Injured:
| Category | Examples |
|---|---|
| Skin/Soft tissue | Laceration, avulsion, amputation |
| Tendon | Flexor, extensor lacerations |
| Nerve | Digital nerve laceration |
| Vascular | Digital artery injury |
| Bone | Fracture, dislocation |
| Nail | Nail bed laceration, subungual hematoma |
Epidemiology
- Very common: ~10% of ED visits
- Work-related injuries common: Machinery, tools
- Sports injuries: Ball-handling, falls
Anatomy
Tendons:
| Tendon | Function |
|---|---|
| FDP | Flexes DIP |
| FDS | Flexes PIP |
| Extensor digitorum | Extends MCP |
| Central slip | Extends PIP |
| Terminal tendon | Extends DIP |
Nerves:
| Nerve | Distribution |
|---|---|
| Radial digital | Lateral aspect of each finger |
| Ulnar digital | Medial aspect of each finger |
Clinical Presentation
History
Key Questions:
Physical Examination
Systematic Approach:
-
Inspect: Position, deformity, swelling, wounds
-
Tendons (Test Each Independently): | Test | Technique | |------|-----------| | FDP | Hold PIP extended, ask to flex DIP | | FDS | Hold other fingers extended, flex PIP | | Extensors | Extend against resistance |
-
Nerves: | Test | Normal | |------|--------| | 2-point discrimination | <5 mm | | Light touch | Intact |
-
Vascular: | Test | Details | |------|---------| | Capillary refill | <2 seconds | | Allen test | Test radial/ulnar artery patency | | Digital Allen | Each digital artery |
-
Bones:
Mechanism (sharp, crush, avulsion, bite)
Common presentation.
Time of injury
Common presentation.
Hand dominance
Common presentation.
Occupation
Common presentation.
Contamination (soil, animal, human bite)
Common presentation.
Tetanus status
Common presentation.
Prior hand surgery
Common presentation.
Red Flags
High-Risk Injuries
| Injury | Concern | Action |
|---|---|---|
| High-pressure injection | Tissue necrosis | Emergent surgery |
| Fight bite (human) | Deep space infection | Exploration, IV antibiotics |
| Complete amputation | Replantation candidate | Consult hand surgery |
| Flexor tendon laceration | Functional loss | Hand surgery referral |
| Open fracture | Infection | Antibiotics, surgery |
| Vascular compromise | Ischemia | Urgent repair |
Specific Injuries
Mallet Finger
| Feature | Details |
|---|---|
| Mechanism | Forced flexion of extended DIP |
| Finding | Inability to extend DIP |
| X-ray | May show avulsion fracture |
| Treatment | Splint DIP in extension × 6-8 weeks continuously |
| Referral | If open, large fracture fragment, or swan-neck developing |
Boutonniere Deformity
| Feature | Details |
|---|---|
| Mechanism | Central slip rupture at PIP |
| Finding | Flexed PIP, hyperextended DIP |
| May be delayed | Days after injury |
| Treatment | Splint PIP in extension × 6 weeks |
| Referral | If open or severe |
Jersey Finger
| Feature | Details |
|---|---|
| Mechanism | Forced extension of flexed DIP (grabbing jersey) |
| Finding | Unable to flex DIP (FDP avulsion) |
| Ring finger most common | |
| Treatment | Surgical repair (hand surgery) |
Boxer's Fracture
| Feature | Details |
|---|---|
| Location | 5th metacarpal neck |
| Mechanism | Punching with closed fist |
| Acceptable angulation | <40-70° (varies by finger) |
| Treatment | Ulnar gutter splint; surgery if excessive angulation, rotational deformity |
Bennett Fracture
| Feature | Details |
|---|---|
| Location | Base of 1st metacarpal, intra-articular |
| Mechanism | Axial load on thumb |
| Treatment | Thumb spica splint; often needs ORIF |
| Refer | Hand surgery |
Gamekeeper's/Skier's Thumb
| Feature | Details |
|---|---|
| Mechanism | Forced abduction of thumb |
| Location | UCL of thumb MCP |
| Finding | Laxity on valgus stress |
| X-ray | May show avulsion |
| Treatment | Thumb spica splint; surgery if complete rupture (Stener lesion) |
Subungual Hematoma
| Feature | Details |
|---|---|
| Cause | Crush injury to nail |
| Finding | Blood under nail, pain |
| Treatment | Trephination if >0% or very painful |
| If nail margin intact | Simple trephination |
| If nail avulsed or large laceration | Repair nail bed |
Fight Bite (Clenched Fist Injury)
| Feature | Details |
|---|---|
| Mechanism | Punch to mouth; tooth penetrates MCP |
| High infection risk | Oral flora, Eikenella |
| May seem minor | Small laceration over MCP |
| Treatment | Exploration if MCP involved, irrigation, IV antibiotics |
| Antibiotics | Ampicillin-sulbactam or amoxicillin-clavulanate |
High-Pressure Injection Injury
| Feature | Details |
|---|---|
| Mechanism | Industrial injection (grease, paint) |
| Appearance may be benign | Small entry wound |
| Serious injury | Extensive tissue damage, necrosis |
| Treatment | EMERGENT surgical exploration and debridement |
Diagnostic Approach
Imaging
X-Ray:
| Indication | Views |
|---|---|
| Trauma | PA, lateral, oblique |
| Foreign body suspected | May detect glass, metal |
| Dislocation | Pre- and post-reduction |
Ultrasound
- Foreign body detection
- Flexor tendon evaluation
Treatment
General Wound Care
| Step | Details |
|---|---|
| Irrigation | Copious normal saline |
| Debridement | Remove devitalized tissue |
| Tetanus | Update if needed |
| Closure | Primary for clean lacerations |
Tendon Injuries
| Type | Treatment |
|---|---|
| Extensor (over MCP) | ED repair possible if experienced |
| Extensor (over PIP, DIP) | Splinting (mallet, boutonniere) |
| Flexor | Hand surgery referral (do not repair in ED) |
Nerve Injuries
| Type | Treatment |
|---|---|
| Partial | May observe or repair |
| Complete digital nerve | Hand surgery referral |
Fractures
| Type | Treatment |
|---|---|
| Stable, non-displaced | Splint, follow-up |
| Displaced, rotational deformity | Hand surgery |
| Open | IV antibiotics, surgery |
| Thumb | Thumb spica splint |
| Fingers | Buddy tape or splint |
Splinting
| Injury | Splint |
|---|---|
| Finger fracture | Buddy tape, finger splint |
| Mallet finger | DIP splint in extension |
| Boxer's fracture | Ulnar gutter |
| Bennett/Thumb injuries | Thumb spica |
| Wrist/Hand fractures | Volar or dorsal wrist splint |
Disposition
Discharge Criteria
- Simple lacerations, repaired
- Stable fractures, splinted
- Extensor tendon injuries managed conservatively
- Wound care education provided
- Follow-up arranged
Referral to Hand Surgery
| Indication | Urgency |
|---|---|
| Flexor tendon laceration | <7 days (semi-emergent) |
| Complete nerve laceration | Days to weeks |
| Open fracture | Urgent |
| Amputation (replant candidate) | Emergent |
| High-pressure injection | Emergent |
| Fight bite with joint involvement | Urgent |
| Displaced or rotational fracture | Days |
Follow-Up
| Situation | Follow-Up |
|---|---|
| Simple laceration | Suture removal 10-14 days |
| Fracture | Orthopedics/Hand surgery in 5-7 days |
| Tendon injury | Hand surgery within 7 days |
Patient Education
Wound Care
- Keep hand elevated
- Keep dressing clean and dry
- Change dressing as instructed
- Watch for signs of infection
Splint Care
- Keep splint dry
- Do not remove unless instructed
- Elevate to reduce swelling
Warning Signs to Return
- Increasing pain, swelling, or redness
- Numbness or tingling
- Color change (pale, blue)
- Inability to move fingers
- Fever
Quality Metrics
Performance Indicators
| Metric | Target | Rationale |
|---|---|---|
| Tendon exam documented | 100% | Detect injury |
| Neurovascular exam documented | 100% | Detect injury |
| Appropriate splint applied | >5% | Immobilization |
| Hand surgery referral for flexor tendon | 100% | Standard of care |
Documentation Requirements
- Mechanism of injury
- Tendon function (FDP, FDS, extensors)
- Sensory exam (2-point discrimination)
- Vascular exam
- X-ray findings
- Treatment and follow-up
Key Clinical Pearls
Diagnostic Pearls
- Test tendons against resistance: Weak = partial tear
- FDP = Flex DIP; FDS = Flex PIP: Know the tests
- 2-point discrimination <5 mm is normal: >10 mm = injury
- Rotational deformity on fist = Unacceptable: Needs surgery
- Fight bite over MCP = High risk: May not look bad
- High-pressure injection looks benign but is surgical emergency
Treatment Pearls
- Do NOT repair flexor tendons in ED: Refer to hand surgery
- Mallet finger: Splint DIP in extension continuously × 6 weeks
- Trephinate subungual hematoma if painful or >50%
- Ulnar gutter for boxer's fracture: MCP at 70-90°, PIP/DIP slight flexion
- Thumb spica for thumb injuries: Include wrist
- Fight bites need IV antibiotics and often exploration
Disposition Pearls
- Most simple lacerations can be discharged: With follow-up
- Refer flexor tendon, nerve, and complex injuries
- Emergent referral for high-pressure injection, amputation
- Follow-up fractures with orthopedics/hand surgery
References
- Chung KC, Spilson SV. The frequency and epidemiology of hand and forearm fractures in the United States. J Hand Surg Am. 2001;26(5):908-915.
- Tang JB. Tendon injuries in the hand. Lancet. 2018;391(10121):658.
- Meals C, Meals R. Hand fractures: A review of current treatment strategies. J Hand Surg Am. 2013;38(5):1021-1031.
- Henry MH. Fractures of the proximal phalanx and metacarpals in the hand. J Hand Surg Am. 2008;33(3):436-453.
- Bindra RR, et al. High-pressure injection injuries of the hand. J Hand Surg Am. 2004;29(3):528-533.
- Tintinalli JE, et al. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 9th ed. 2020.
- ACEP. Clinical Policy: Hand Injuries. 2019.
- UpToDate. Overview of hand infections. 2024.