Makindo Medical Notes

A Boxer’s fracture refers to a fracture of the neck of the 5th metacarpal, typically from a blow with a clenched fist. 🥊 It is the most common hand fracture, often seen after punching a wall or another person. Although called a “Boxer’s” fracture, it is more typical of amateur fighters or accidental trauma rather than trained boxers.

⚡ Mechanism of Injury

When the fist strikes a hard surface, the impact forces the metacarpal head into the palm, producing volar angulation. ➡️ The 5th metacarpal tolerates angulation better than the index/middle, but rotational deformities (🔄 fingers crossing when flexed) are poorly tolerated as they impair grip.

🩺 Clinical Presentation

• 🔥 Pain and swelling over the dorsal hand (little finger side).
• 👀 Loss of knuckle prominence (“sunken knuckle”).
• ✊ Pain/limitation when forming a fist.
• 🔄 Finger rotation or scissoring when flexing fingers.
• 💜 Bruising on the dorsum of the hand.
• 🦠 Always check for a “fight bite” (human bite wound) over MCP joint → risk of septic arthritis/osteomyelitis.

🔍 Diagnosis

• Clinical exam: Tenderness, swelling, loss of knuckle contour. Check rotation → fingers should point to scaphoid tubercle.
• Imaging:
  • 📸 AP, lateral, and oblique X-rays of the hand.
  • Look for angulation, rotation, and associated fractures.
  • 💡 Compare finger alignment in a fist—misaligned nails = rotation.

🛠️ Management

Management depends on angulation, rotation, and fracture stability. 🧾

• ✅ Conservative:
  • Acceptable if ≤40° volar angulation and no rotation.
  • Ulnar gutter splint for 3–6 weeks with “safe hand position” 🤚.
  • Some UK centres use functional bandage + early mobilisation to reduce stiffness.
• 🔄 Closed Reduction:
  • Indicated if >40° angulation.
  • Done with gentle traction + dorsal pressure.
• 🔧 Surgery:
  • Persistent rotational deformity.
  • Unstable/displaced fracture after reduction.
  • Open fractures / human bite injuries.
  • Multiple metacarpal fractures affecting function.

📅 Follow-up & Prognosis

Regular review is vital to ensure stability. 🔁 Repeat X-ray at 1 week. Hand therapy after splint removal improves motion and grip.

• ⏱️ Most fractures heal in 4–6 weeks with excellent function.
• 👊 Flattened knuckle often persists but rarely impairs function.
• 💪 Physiotherapy/hand therapy key to regaining strength and dexterity.
• ⚠️ Malunion may cause cosmetic deformity or reduced grip.

⚠️ Complications

• 📉 Malunion → cosmetic deformity.
• 🔄 Rotational deformity → impaired grip, finger overlap.
• 🪢 Stiffness or reduced range of motion.
• 🩸 Non-union (rare).
• 🦠 Infection (fight bite → septic arthritis/osteomyelitis).

📊 Quick Teaching Table

Feature	Key Teaching Point
💡 Angulation	Up to 40° acceptable in 5th metacarpal; less tolerated in 2nd/3rd.
🔄 Rotation	Always unacceptable—must be corrected surgically if persistent.
🦠 Fight bite	Urgent washout + IV antibiotics (risk of septic arthritis).
🛠️ Splint position	“Safe hand” = wrist 20° ext, MCP 70–90° flexion, IP joints straight.
📅 Follow-up	X-ray at 1 week; early physio post-splint to avoid stiffness.