22.1 Acute Ambulatory Fractures & Initial Splinting

Systematic Fracture Assessment & Neurovascular Examination

Musculoskeletal trauma represents one of the most frequent reasons for acute presentations in family medicine, urgent care, and emergency settings. The primary objective during initial assessment is the rapid identification of limb-threatening or life-threatening pathology, systematic evaluation of soft tissue and neurovascular integrity, and appropriate temporary stabilization.

Neurovascular Examination: The Essential First Step

Prior to performing any manipulation, reduction, splinting, or obtaining radiographic studies, a detailed neurovascular assessment distal to the site of injury must be documented. Any subsequent manipulation or splint application mandates an immediate repeat neurovascular examination to ensure that reduction maneuvers or compressive wraps have not compromised neurovascular integrity.

1. Upper Extremity Neurovascular Examination:

   • Radial Nerve:
     • Motor Function: Active wrist extension against gravity/resistance and active extension of the fingers at the metacarpophalangeal (MCP) joints ("thumbs up" sign).
     • Sensory Territory: Dorsal first web space (dorsum of the hand between the first and second metacarpals).
   • Median Nerve:
     • Motor Function (Main Trunk): Palmar abduction of the thumb against resistance (abductor pollicis brevis) and thumb-to-fifth-digit opposition.
     • Motor Function (Anterior Interosseous Nerve branch - AIN): Distal flexion of the thumb interphalangeal (IP) joint and index finger distal interphalangeal (DIP) joint to form the classic "OK" sign (flexor pollicis longus and flexor digitorum profundus I/II).
     • Sensory Territory: Palmar aspect of the index finger distal pad and thumb pad.
   • Ulnar Nerve:
     • Motor Function: Finger abduction and adduction against resistance (dorsal and palmar interossei); thumb adduction (adductor pollicis; tested via Froment's sign, where compensatory IP joint flexion reveals adductor weakness).
     • Sensory Territory: Palmar and dorsal aspects of the distal fifth digit and hypothenar eminence.
   • Vascular Perfusion:
     • Palpation of radial and ulnar arterial pulses at the wrist; documentation of symmetrical volume.
     • Capillary refill time in each distal digit (normal <2 seconds).
     • Assessment of skin color, warmth, and distal digital turgor.

2. Lower Extremity Neurovascular Examination:

   • Femoral / Saphenous Nerve:
     • Motor Function: Active knee extension against resistance (quadriceps femoris).
     • Sensory Territory: Medial distal thigh, medial knee, and medial aspect of the lower leg/calf.
   • Common Peroneal (Fibular) Nerve:
     • Deep Peroneal Nerve: Active ankle dorsiflexion and active great toe extension against resistance (extensor hallucis longus); sensation over the first dorsal web space (between first and second toes).
     • Superficial Peroneal Nerve: Active ankle eversion (peroneus longus/brevis); sensation over the anterolateral lower leg and the broad dorsum of the foot.
   • Tibial Nerve:
     • Motor Function: Active ankle plantarflexion (gastrocnemius/soleus) and active flexion of the toes (flexor hallucis longus, flexor digitorum longus).
     • Sensory Territory: Plantar aspect of the foot, heel, and plantar digital pads.
   • Vascular Perfusion:
     • Palpation of the dorsalis pedis artery (dorsum of the foot between first and second metatarsals) and the posterior tibial artery (posterior and inferior to the medial malleolus).
     • Capillary refill of the digits (<2 seconds); continuous assessment of extremity warmth and Doppler ultrasound interrogation if pulses are non-palpable.

Assessment of Soft Tissues and Skin Integrity

• Open vs. Closed Fracture: Every laceration, abrasion, or punctate skin break in proximity to an underlying fracture must be presumed an open fracture until proven otherwise. Even a microscopic 1 mm puncture created by a transiently protruding bone spike that subsequently retracted constitutes an open fracture with deep tissue contamination.
• Skin Tenting & Impending Skin Necrosis: High-energy displacement of bony fragments can severely stretch and tent overlying skin. Tenting produces focal cutaneous ischemia manifested by blanching, extreme thinning, and loss of capillary refill. Unrelieved tenting progresses to full-thickness cutaneous necrosis within hours, converting a closed fracture into an open fracture. Immediate gentle closed longitudinal traction to disimpact the bone fragment and relieve cutaneous tension is mandatory.
• Puckering Sign: Cutaneous puckering or dimpling indicates that bone ends or soft tissues are incarcerated within deep fascial planes or buttonholed through subcutaneous tissues, frequently heralding irreducible fractures that necessitate open operative reduction.

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Principles of Orthopedic Radiography

The Rule of Orthogonal Views

Radiographic evaluation of acute skeletal trauma adheres to unyielding foundational tenets:

1. Minimum Two Perpendicular Projections:
   • A single radiographic view is completely inadequate and medically unacceptable ("one view is no view").
   • A standard minimum of two orthogonal projections at 90 degrees to each other—specifically Anteroposterior (AP) and True Lateral views—must be obtained for every suspected skeletal injury. An oblique or non-displaced fracture evident on a lateral view may be entirely invisible on an AP view.
2. Inclusion of the Joint Above and Joint Below:
   • Long bone radiographs (clavicle, humerus, radius/ulna, femur, tibia/fibula) must capture the full length of the diaphysis and encompass the joint immediately proximal and the joint immediately distal to the suspected fracture.
   • Failure to image adjacent joints leads to missed dislocations, associated partner fractures, and disruption of kinetic ring structures (e.g., missed radial head dislocation in a Monteggia fracture-dislocation; missed proximal fibular fracture in a Maisonneuve injury).
3. Specialized Oblique & Stress Views:
   • Complex anatomical structures require supplementary projections: scaphoid views for carpal trauma, mortise views (AP with 15-20 degrees of internal rotation) for the ankle, and axial calcaneal (Harris) views for hindfoot trauma.

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Open Fracture Emergency Management: The Gustilo-Anderson Protocol

Open fractures represent true orthopedic emergencies characterized by direct communication between the external environment and the fracture hematoma, conferring high risks of osteomyelitis, nonunion, and limb loss.

Gustilo-Anderson Classification System

Special Caveat: Any open fracture sustained in an agricultural setting, barnyard, soil-contaminated environment, or caused by high-velocity gunshot trauma is automatically classified as a Type III injury regardless of the physical dimensions of the cutaneous laceration.

Immediate Emergency Department Management Protocol

1. Time-to-Antibiotic Window (<3 Hours):
   • Intravenous antibiotic administration within 3 hours of injury is the single most critical physician-dependent intervention to prevent acute and chronic osteomyelitis. A delay beyond 3 hours increases the infection rate by more than threefold.
   • Type I and Type II Fractures:
     • First-line: Cefazolin 2 g IV every 8 hours (weight-adjusted: 3 g IV if patient >120 kg).
     • Severe Beta-Lactam / Penicillin Allergy: Clindamycin 900 mg IV every 8 hours OR Vancomycin 15-20 mg/kg IV every 12 hours.
   • Type III Fractures:
     • Broaden coverage to encompass Gram-negative bacilli: Cefazolin 2 g IV every 8 hours PLUS Gentamicin 5 mg/kg IV once daily (or Ceftriaxone 2 g IV daily as a non-nephrotoxic alternative).
   • Farm, Soil, Barnyard, or Fecal Contamination:
     • High risk of spore-forming anaerobic infection (Clostridium perfringens / gas gangrene).
     • ADD high-dose Penicillin G 4 million units IV every 4 hours (or Ampicillin-sulbactam 3 g IV every 6 hours).
   • Marine / Freshwater Contamination:
     • High risk of Vibrio vulnificus or Aeromonas hydrophila.
     • Add Doxycycline 100 mg IV BID PLUS Ceftazidime 2 g IV q8h or a fluoroquinolone.
2. Tetanus Prophylaxis:
   • If the patient has received ≥3 lifetime doses of tetanus toxoid: administer Tdap or Td intramuscularly if the last booster was >5 years ago for dirty/open wounds (>10 years for clean minor wounds).
   • If the patient has received <3 lifetime doses or immunization history is unknown/uncertain: administer Tdap 0.5 mL IM PLUS Tetanus Immune Globulin (TIG) 250 units IM at separate anatomical injection sites using separate syringes.
3. Local Wound Management & Splinting:
   • Remove gross superficial debris (twigs, gravel, clothing) from the surface.
   • DO NOT perform blind deep wound probing, local exploration, or aggressive forceful scrubbing in the emergency room.
   • DO NOT push protruding, contaminated bone ends back into the deep wound bed; if reduction maneuvers cause protruding bone to retract, explicitly notify the operating orthopedic surgeon.
   • Irrigate superficial debris gently with sterile isotonic saline; apply a sterile, saline-moistened gauze dressing covered with a dry sterile wrap.
   • Apply a rigid, non-circumferential stabilizing splint.
4. Emergent Orthopedic Consultation:
   • Urgent transfer to the operating theater for formal surgical irrigation and debridement under general anesthesia, ideally within 12 to 24 hours of injury.

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Upper Extremity Ambulatory Fractures & Splinting Techniques

                    UPPER EXTREMITY FRACTURE OVERVIEW

  ┌───────────────────────┐  ┌───────────────────────┐  ┌───────────────────────┐
  │   CLAVICLE FRACTURE   │  │ DISTAL RADIUS (COLLES)│  │   SCAPHOID FRACTURE   │
  ├───────────────────────┤  ├───────────────────────┤  ├───────────────────────┤
  │ • Middle third: 80%   │  │ • Dorsal displacement │  │ • Anatomical snuffbox │
  │ • Sling immobilization│  │ • "Dinner fork" deform│  │ • Retrograde blood    │
  │ • Surgery: >2cm short,│  │ • Sugar-tong splint   │  │ • High AVN risk       │
  │   tenting, neurovasc  │  │ • Hematoma block 10mL │  │ • Thumb spica splint  │
  └───────────────────────┘  └───────────────────────┘  └───────────────────────┘

1. Clavicle Fractures

• Epidemiology & Anatomy: Represents 2% to 5% of all adult fractures. Anatomically divided into:
  • Middle Third (Midshaft): Accounts for 80% of all clavicle fractures. Result of direct lateral shoulder impact.
  • Distal Third (Lateral): Accounts for 15%. Often involves coracoclavicular (CC) ligament disruption.
  • Proximal Third (Medial): Accounts for 5%. Requires high energy; evaluate for mediastinal vascular injury.
• Physical Examination: Visible deformity, localized bony tenderness, crepitus, and ecchymosis. Careful assessment of the subclavian vessels (radial pulses) and brachial plexus is mandatory. Palpate for subcutaneous air or respiratory distress indicating associated pneumothorax.
• Conservative Management:
  • Standard treatment for non-displaced or minimally displaced midshaft fractures is conservative immobilization using a simple arm sling (or sling and swathe).
  • Board Pearl: Randomized trials demonstrate that figure-of-eight bandages provide no improvement in alignment, healing rates, or functional outcomes compared to a simple sling, but cause significantly higher rates of axillary skin breakdown, pressure sores, and transient paresthesias. Simple sling immobilization for 3 to 4 weeks, followed by progressive active-assisted range of motion, is the evidence-based gold standard.
• Indications for Urgent Orthopedic Surgical Referral (ORIF):
  1. Open fracture or impending open fracture manifested by severe skin tenting and blanching;
  2. Concurrent neurovascular compromise (subclavian artery/vein compression, brachial plexus palsy);
  3. Complete displacement with shortening >2 cm (associated with high nonunion rates [up to 15-20%] and permanent shoulder girdle dysfunction);
  4. 100% cortical displacement without bony contact in an active individual;
  5. Floating shoulder (ipsilateral clavicle midshaft fracture and scapular neck fracture yielding an unstable glenoid fragment);
  6. Symptomatic nonunion after 12 to 16 weeks of conservative therapy.

2. Distal Radius Fractures: Colles versus Smith

Distal radius fractures are the most common fractures of the upper extremity, typically occurring secondary to a fall onto an outstretched hand (FOOSH).

            DISTAL RADIUS DEFORMITY COMPARISON

     COLLES FRACTURE                   SMITH FRACTURE
  (Fall on Outstretched Hand)       (Fall on Flexed Wrist)

       Dorsal Displacement               Volar Displacement
       "Dinner Fork"                     "Garden Spade"
         ┌───────┐                         ┌───────┐
         │ Hand  │                         │ Hand  │
     ────┘       │                     ────┼───────┘
                 │                         │
      Forearm    │                         │   Forearm
    ─────────────┘                         └─────────────

• Colles Fracture:
  • Mechanism: FOOSH with the wrist positioned in pronounced dorsiflexion/extension.
  • Deformity: Extra-articular metaphyseal fracture with dorsal displacement, dorsal angulation (loss of normal 11-degree volar tilt), and radial shortening. Produces the classic "dinner fork" deformity.
• Smith Fracture ("Reverse Colles"):
  • Mechanism: Fall onto a hyperflexed wrist or direct high-energy impact to the dorsal forearm.
  • Deformity: Extra-articular fracture with volar (palmar) displacement and volar angulation of the distal radial fragment. Produces the "garden spade" deformity.
  • Significance: Inherently unstable due to dynamic flexor tendon pull; frequently requires operative fixation.
• Barton Fracture:
  • Fracture-dislocation of the radiocarpal joint with intra-articular shear involvement of either the dorsal or volar rim of the distal radius. Highly unstable; universally requires operative intervention.

Hematoma Block Technique

Providing effective bedside analgesia is required prior to attempting closed reduction of distal radius fractures:

• Prepare the dorsal skin over the fracture site with chlorhexidine or povidone-iodine in a sterile fashion.
• Palpate the dorsal step-off or depression corresponding to the fracture line.
• Using a 20- to 22-gauge 1.5-inch needle attached to a 10-12 mL syringe containing 10 mL of 1% lidocaine without epinephrine, insert the needle directly into the fracture gap from the dorsal aspect.
• Aspirate dark venous fracture hematoma blood to definitively confirm intra-hematoma positioning.
• Slowly inject 8 to 10 mL of lidocaine into the fracture hematoma; resistance should be minimal. Allow 10 to 15 minutes for complete regional anesthesia to take effect.

Closed Reduction Technique for Colles Fracture

1. Place the patient supine. Apply sustained axial traction across the hand and thumb (or utilize finger traps with 10-15 lbs of counter-traction at the elbow flexed at 90 degrees) for 5 minutes to overcome muscle spasm and restore length.
2. Disimpact the fragments by briefly accentuating the dorsal deformity.
3. Apply strong, directed palmar pressure over the distal fragment while applying counter-pressure on the proximal radial shaft, mobilizing the wrist into palmar flexion, ulnar deviation, and pronation.

Splint Application: The Sugar-Tong Splint

• Distal radius fractures must be immobilized in a Sugar-Tong Splint (not a simple volar splint, which allows pronation/supination).
• Splint Construction: Plaster or fiberglass (8-10 layers of 3- or 4-inch material) extends from the dorsal metacarpal heads, courses proximally along the dorsal forearm, wraps securely around the posterior elbow, and extends along the volar forearm to terminate at the distal palmar crease.
• Position of Function: The wrist is maintained in slight flexion (10-15 degrees) and slight ulnar deviation. Avoid extreme palmar flexion ("Cotton-Loder position"), which produces median nerve compression in the carpal tunnel.
• Critical Warning: Never apply a circumferential plaster or fiberglass cast acutely. Post-traumatic soft tissue swelling within a rigid circumferential cast dramatically increases intracompartmental pressures, causing acute compartment syndrome of the forearm.

3. Scaphoid Fractures

• Anatomy & Unique Vascular Supply:
  • The scaphoid (navicular) is the most frequently fractured carpal bone (~70% of carpal injuries).
  • Blood supply to the scaphoid is uniquely precarious: branches of the radial artery enter the bone via the distal pole and waist in a retrograde intraosseous fashion to supply the proximal pole.
  • Consequently, fractures through the scaphoid waist or proximal pole deprive the proximal fragment of arterial inflow, resulting in high rates of avascular necrosis (AVN) of the proximal pole (seen in up to 30-40% of waist fractures and >90% of proximal pole fractures), delayed union, nonunion, and post-traumatic arthritis (scaphoid nonunion advanced collapse [SNAC] wrist).

                      SCAPHOID VASCULAR VULNERABILITY

                         Radial Artery Inflow
                                  │
                                  ▼
                        ┌───────────────────┐
                        │    Distal Pole    │ ◄── Rich Blood Supply
                        ├───────────────────┤
                        │   Scaphoid Waist  │ ◄── Most Common Fracture (70%)
                        ├───────────────────┤
                        │   Proximal Pole   │ ◄── ISOLATED FROM ARTERIAL INFLOW
                        └───────────────────┘     High Risk of AVN & Nonunion!
                                  ▲
                       (Retrograde Flow Lost)

• Mechanism of Injury: FOOSH with impact concentrated on the thenar eminence.
• Clinical Examination Triad:
  1. Anatomical Snuffbox Tenderness: Tenderness to palpation in the triangular depression bordered by the extensor pollicis longus (EPL) tendon medially and the extensor pollicis brevis (EPB) and abductor pollicis longus (APL) tendons laterally (sensitivity ~90%, but lower specificity);
  2. Scaphoid Tubercle Tenderness: Tenderness elicited on the volar wrist at the base of the thenar eminence;
  3. Axial Thumb Compression Pain: Pain elicited by compressing the first metacarpal longitudinally into the scaphoid.
• Radiographic Limitations & Clinical Management Protocol:
  • Standard wrist radiographs including dedicated scaphoid views (PA with ulnar deviation, lateral, semi-pronated oblique, and semi-supinated oblique) fail to detect 15% to 20% of acute scaphoid fractures on initial evaluation.
  • The Golden Scaphoid Management Rule:
    • If a patient presents with traumatic wrist pain and clinical tenderness in the anatomical snuffbox or scaphoid tubercle, they must be managed as a presumed scaphoid fracture regardless of negative initial radiographs.
    • Immobilize the wrist and thumb in a Short-Arm Thumb Spica Splint.
    • Instruct the patient to remain strictly non-weight-bearing with the wrist and schedule repeat clinical examination and plain radiographs in 10 to 14 days (when osteoclastic resorption along the fracture line renders occult fractures radiographically visible).
    • Alternative Modern Strategy: Obtain an immediate non-contrast MRI of the wrist (or high-resolution thin-cut wrist CT), which demonstrates 100% sensitivity and specificity, eliminates 2 weeks of unnecessary immobilization in patients without fracture, and detects alternative ligamentous or carpal injuries.

4. Boxer's Fracture (5th Metacarpal Neck)

• Pathomechanics: Fracture of the neck of the fifth (or fourth) metacarpal, characteristically sustained when striking a solid object with a clenched fist.
• Physical Examination:
  • Dorsal soft tissue swelling, loss of knuckle prominence, and point tenderness over the fifth metacarpal neck.
  • Rotational Alignment Assessment: The single most critical physical examination step. In normal anatomical alignment, when the MCP and IP joints are flexed into a fist, the axes of all four fingers point toward a single reference landmark: the scaphoid tubercle. Any rotational malalignment results in finger overlap ("scissoring") during flexion, severely impairing grip function. Even 2 to 5 degrees of rotational deformity is functionally unacceptable and warrants closed reduction or surgical correction.
• Acceptable Dorsal Angulation Guidelines:
  • Due to the high mobility and compensatory sagittal plane motion of the fifth carpometacarpal (CMC) joint (approximately 20-30 degrees of motion), the fifth metacarpal neck tolerates substantial dorsal angulation without permanent functional deficit.
  • Acceptable Dorsal Angulation Thresholds:
    • 5th Metacarpal Neck: Up to 30 to 40 degrees (some authorities permit up to 45-50 degrees) of dorsal angulation is acceptable conservatively, provided there is zero rotational deformity.
    • 4th Metacarpal Neck: Tolerates up to 20 degrees.
    • 2nd and 3rd Metacarpal Necks: The index and middle CMC joints are rigid, fixed joints with zero compensatory motion; they tolerate <10 to 15 degrees of angulation; higher angulation requires anatomical reduction.
• Closed Reduction (The Jahss Maneuver):
  • Perform an ulnar nerve block or local hematoma block.
  • Flex both the MCP joint and proximal interphalangeal (PIP) joint to 90 degrees.
  • Apply upward dorsal pressure along the shaft of the proximal phalanx while stabilizing and pushing downward on the metacarpal shaft. The tightened collateral ligaments of the flexed MCP joint transmit upward force to reduce the volarly displaced metacarpal head.
• Splinting: The Ulnar Gutter Splint:
  • Plaster or fiberglass extends along the ulnar forearm, wrist, and 4th and 5th digits.
  • The Intrinsic-Plus ("Safe") Position:
    • Wrist in 20 to 30 degrees of extension;
    • MCP joints flexed to 70 to 90 degrees (keeps collateral ligaments at maximal length, preventing joint contractures and stiffness);
    • Interphalangeal (PIP and DIP) joints in near-full extension (0 to 10 degrees).
• The Human Bite Wound ("Fight Bite") Warning:
  • Any skin break, laceration, or puncture over the dorsal MCP joint following a fist fight must be managed as an open human bite wound contaminated with oral flora (Eikenella corrodens, Staphylococcus aureus, Streptococcus, and anaerobes).
  • The tooth punctures the extensor tendon and joint capsule while the fist is clenched; when the fingers extend, the puncture tracks retract beneath intact skin, locking virulent bacteria into the joint.
  • Never close these wounds primarily. Irrigate copiously, leave open, obtain radiographs to rule out foreign tooth fragments or cortical fracture, and prescribe Amoxicillin-clavulanate 875/125 mg PO BID (or IV Ampicillin-sulbactam 1.5-3.0 g q6h if infected) with 24-hour follow-up.

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Lower Extremity Ambulatory Fractures: Ankle & 5th Metatarsal

1. The Ottawa Ankle and Foot Rules

The Ottawa Ankle and Foot Rules are validated decision instruments demonstrating near 100% sensitivity for identifying clinically significant fractures, reducing unnecessary radiographs by 30% to 40%.

                      THE OTTAWA ANKLE & FOOT RULES

        ANKLE RADIOGRAPHIC SERIES                   FOOT RADIOGRAPHIC SERIES
        (Indicated if pain in malleolar             (Indicated if pain in midfoot
         zone PLUS any of the following)             zone PLUS any of the following)
  ┌────────────────────────────────────────┐  ┌────────────────────────────────────────┐
  │ 1. Bone tenderness along distal 6 cm   │  │ 1. Bone tenderness at the base of the  │
  │    of posterior edge or tip of the     │  │    fifth metatarsal; OR                │
  │    LATERAL malleolus; OR               │  │                                        │
  │ 2. Bone tenderness along distal 6 cm   │  │ 2. Bone tenderness at the NAVICULAR    │
  │    of posterior edge or tip of the     │  │    bone; OR                            │
  │    MEDIAL malleolus; OR                │  │                                        │
  │ 3. Inability to bear weight both       │  │ 3. Inability to bear weight both       │
  │    immediately after injury AND in     │  │    immediately after injury AND in     │
  │    the clinic/ED (for 4 steps).        │  │    the clinic/ED (for 4 steps).        │
  └────────────────────────────────────────┘  └────────────────────────────────────────┘

• Exclusion Criteria: The rules do not apply to patients under 18 years of age (though pediatric Ottawa rules exist), patients with altered mental status, intoxicating substances, distracting injuries, diminished lower extremity sensation (diabetic neuropathy), or presenting >10 days after the initial trauma.

2. Ankle Fractures & The Danis-Weber Classification

The stability of ankle fractures depends upon the integrity of the ankle mortise, comprised of the medial malleolus (and deltoid ligament), lateral malleolus (distal fibula), and the syndesmotic ligament complex (anterior inferior tibiofibular ligament, posterior inferior tibiofibular ligament, and interosseous ligament).

             DANIS-WEBER ANKLE FRACTURE CLASSIFICATION

     WEBER A                     WEBER B                     WEBER C
 (Infrasyndesmotic)          (Transsyndesmotic)          (Suprasyndesmotic)

     │         │                 │         │                 │    *    │  ◄── Fracture above joint
     │         │                 │         │                 ├─────────┤      Syndesmosis TORN
     ├─────────┤                 │    *    │ ◄── Level of    │         │      UNSTABLE -> ORIF
     │         │                 ├─────────┤     plafond     │         │
     │    *    │ ◄── Below joint │         │                 │         │
  ═══╧═════════╧═══           ═══╧═════════╧═══           ═══╧═════════╧═══
   Syndesmosis INTACT          50% Syndesmosis Injured     Syndesmosis DISRUPTED
   STABLE -> Boot              Evaluate Medial Clear Space UNSTABLE -> Operative

• Weber Type A (Infrasyndesmotic):
  • Fibular fracture line is strictly below the level of the tibial plafond.
  • The syndesmotic ligament complex and deltoid ligament are completely intact.
  • The ankle mortise remains stable. Managed conservatively with a short-leg walking boot or cast with weight-bearing as tolerated for 4 to 6 weeks.
• Weber Type B (Transsyndesmotic):
  • Fibular fracture begins at the level of the tibial plafond and extends obliquely upward.
  • The tibiofibular syndesmosis is partially compromised (injured in ~50% of cases).
  • Stability Determination: Assess the medial ankle structures. If the medial malleolus is intact, there is no medial tenderness or hematoma, and the medial clear space on the mortise radiograph is ≤4 mm, the fracture is stable and can be treated conservatively. If there is medial tenderness, ecchymosis, or the medial clear space is widened (>4 mm, indicating complete deltoid ligament tear), the fracture is unstable and requires operative ORIF.
• Weber Type C (Suprasyndesmotic):
  • Fibular fracture is above the level of the tibial plafond.
  • The tibiofibular syndesmotic complex and interosseous membrane are completely disrupted up to the level of the fibular fracture.
  • The fracture is inherently unstable; widens the ankle mortise and requires open reduction and internal fixation (ORIF) with syndesmotic screw or suture-button fixation.

3. The Maisonneuve Fracture: A Classic Diagnostic Pitfall

• Pathoanatomy: A spiral fracture of the proximal third or neck of the fibula associated with disruption of the distal tibiofibular syndesmosis, tearing of the entire interosseous membrane, and either an avulsion fracture of the medial malleolus or a complete rupture of the deep deltoid ligament.
• The Clinical Trap:
  • The patient presents following an external rotation ankle injury complaining exclusively of severe medial ankle pain and swelling. Initial plain ankle radiographs may reveal only an isolated medial malleolus fracture or, even more deceptively, no fracture at all, displaying only widening of the medial clear space (>4 mm) or tibiofibular overlap <6 mm.
  • If the clinician fails to examine the entire lower leg, the high proximal fibular fracture will be missed, leading to unrecognized syndesmotic diastasis, chronic ankle instability, and early debilitating osteoarthritis.
• The Mandated Clinical Rule:
  • Palpate the proximal fibular head and entire fibular shaft in EVERY patient presenting with an acute ankle injury.
  • If tenderness is present at the proximal fibula, or if ankle radiographs show medial clear space widening without a distal fibular fracture, obtain full-length AP and Lateral Tibia/Fibula radiographs immediately.
  • Maisonneuve fractures are inherently unstable Weber C injuries that universally require surgical fixation.

4. Fifth Metatarsal Base Fractures: Zones 1, 2, and 3

Fractures of the base of the fifth metatarsal represent the most frequent foot fractures, but their management diverges drastically based on precise anatomical vascular zones:

                 FIFTH METATARSAL BASE FRACTURE ZONES

                         Toes / Distal Phalanges
                                   ▲
                                   │
    ┌──────────────────────────────┴──────────────────────────────┐
    │                     Metatarsal Diaphysis                    │
    ├─────────────────────────────────────────────────────────────┤
    │ ZONE 3: Diaphyseal Stress Fracture                          │ ◄── Distal to 4-5 Articulation
    │         Chronic repetitive stress; intramedullary screw     │
    ├─────────────────────────────────────────────────────────────┤
    │ ZONE 2: True Jones Fracture                                 │ ◄── Metaphyseal-Diaphyseal Junction
    │         Watershed zone; 30-50% nonunion; strict NWB cast    │     Involves 4th-5th intermetatarsal joint
    ├─────────────────────────────────────────────────────────────┤
    │ ZONE 1: Pseudo-Jones / Tuberosity Avulsion Fracture         │ ◄── Proximal Tuberosity / Apophysis
    │         Peroneus brevis / plantar fascia; WB boot / shoe    │
    └─────────────────────────────────────────────────────────────┘

• Zone 1: Tuberosity Avulsion Fracture ("Pseudo-Jones"):
  • Anatomy: Avulsion of the cortical tuberosity (styloid process) at the proximal tip of the metatarsal base. Caused by sudden inversion of a plantarflexed foot with avulsion by the lateral cord of the plantar aponeurosis or the peroneus brevis tendon.
  • Vascularity & Prognosis: The tuberosity enjoys an abundant vascular network supplied by cancellous metaphyseal bone. Nonunion is exceedingly rare (<1%).
  • Management: Conservative, symptomatic management with weight-bearing as tolerated in a stiff-soled shoe, rigid post-op shoe, or removable walking boot for 3 to 4 weeks. Progression to regular footwear as pain allows.
• Zone 2: True Jones Fracture:
  • Anatomy: A transverse fracture located at the metaphyseal-diaphyseal junction, situated approximately 1.5 to 3 cm distal to the proximal tuberosity tip. The fracture line extends into the fourth and fifth intermetatarsal articulation.
  • Pathophysiology: This anatomical region represents an extreme hypovascular watershed zone supplied only by an intraosseous nutrient artery entering mid-shaft that arborizes retrograde. Fractures disrupt this tenuous intraosseous inflow, resulting in very high rates of delayed union (30% to 50%) and persistent nonunion.
  • Management:
    • Non-Operative: Strict non-weight-bearing (NWB) short-leg cast for 6 to 8 weeks (up to 12 weeks), verified by radiographic evidence of bridging callus before initiating protected weight-bearing.
    • Operative: Percutaneous intramedullary screw fixation is strongly recommended as first-line therapy for competitive athletes, high-demand laborers, or displaced fractures to achieve rapid union and minimize recurrence.
• Zone 3: Proximal Diaphyseal Stress Fracture:
  • Located distal to the fourth-fifth intermetatarsal articulation within the proximal 1.5 cm of the diaphysis. Result of chronic repetitive microtrauma (often seen in military recruits, runners, or basketball players with cavovarus foot alignment).
  • Radiographs characteristically demonstrate cortical thickening, periosteal reaction, and medullary canal narrowing. High failure rates with conservative casting; frequently requires intramedullary screw fixation with or without bone grafting.