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Mnemonics, Simplified Concepts & Thoughts

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Mnemonics, Simplified Concepts & Thoughts

Perkin’s Timetable for Fracture Healing

Dr. Sulabh Kumar Shrestha, MS Orthopedics, Oct 19, 2022

One needs to understand the difference between bone union and consolidation first

UnionConsolidation
DefinitionPartial/Incomplete repairFull/Complete repair
CallusCalcifiedOssified
Attempted angulationPainfulPainless
Fracture line in X-rayStill visibleObliterated and crossed by bony trabeculae
Full weight bearingCannot be undertakenCan be undertaken
Reference: Physiotherapy in Orthopaedics: A Problem-Solving Approach by Karen Atkinson, Fiona J. Coutts, Anne-Marie Hassenkamp
bone healing
Bill Rhodes from Asheville, CC BY 2.0, via Wikimedia Commons

Perkin’s rule

Named after: George Perkins

According to Oxford handbook of clinical surgery:

1. Fractures of cancellous (metaphyseal) bone will take 6 weeks to unite.

2. Fracture of cortical (diaphyseal) bone will take 12 weeks to unite.

3. Fracture of tibia (because of poor blood supply) will take 24 weeks to unite.

4. Time to union for children equals the age of child in years plus 1. Common sense needs to be applied when applying the rule to fracture of cancellous bone in older children.

Reference: Oxford Handbook of Clinical Surgery, 5e by Anil Agarwal, Santhini Jeyarajah, Rhiannon Harries, Greg McLatchie, Ruwan Weerakkody

Other versions:

  1. Spiral or oblique fracture in upper limbs unite in 3 weeks.
  2. For lower limbs: multiply by 2
  3. For transverse fractures: multiply by 2
  4. For consolidation: multiply by 2
  5. Full remodeling: Double the time of consolidation
SpiralTransverse
FractureUnionConsolidationUnionConsolidation
Upper limb3 weeks6 weeks6 weeks12 weeks
Lower limb6 weeks12 weeks12 weeks24 weeks
Reference: Fracture – Long Bones (publishing.service.gov.uk)

dr. sulabh kumar shrestha
Dr. Sulabh Kumar Shrestha, MS Orthopedics

He is the section editor of Orthopedics in Epomedicine. He searches for and share simpler ways to make complicated medical topics simple. He also loves writing poetry, listening and playing music. He is currently pursuing Fellowship in Hip, Pelvi-acetabulum and Arthroplasty at B&B Hospital.

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PGMEE, MRCS, USMLE, MBBS, MD/MS Musculoskeletal systemOrthopedics

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Comments (2)

  1. Alphons pinto says:
    Sep 13, 2025 at 2:30 pm

    My right leg tibia fracture on 30-04-2025 put the rod to leg and operated. Now i am walking with the help of walker. After 4 months doctor suggest to sinle walker. Can i walk freely with out single walker in next 2 months i. e for the month of Nov 2025 pl give suggestion to mr. Thsnk you

    Reply
  2. Dr. Sulabh Kumar Shrestha, MS Orthopedics says:
    Sep 15, 2025 at 2:02 am

    It seems like you underwent intramedullary nail fixation of your tibia. Thank you for sharing your recovery progress. The timeline for walking freely without a walker varies for each individual depending on factors such as the severity of the fracture, healing on X-rays, muscle strength, and physiotherapy progress.

    Reply

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