Bone Fracture and healing Prof. Mamoun Kremli AlMaarefa College
Definition of Fracture A break in the continuity bone Often associated with soft tissue injury Soft tissue injuries might be more serious than the fracture
Etiology Motor Vehicle Accident Fall Sport injuries Vigorous Exercise Bone Diseases Osteoporosis Osteomyelitis Cyst, …
Etiology Motor Vehicle Accident Fall Sport injuries Vigorous Exercise Bone Diseases Osteoporosis Osteomyelitis Cyst, …
Etiology Motor Vehicle Accident Fall Sport injuries Vigorous Exercise Bone Diseases Osteoporosis Osteomyelitis Cyst, …
Etiology Motor Vehicle Accident Fall Sport injuries Vigorous Exercise Bone Diseases Osteoporosis Osteomyelitis Cyst, …
Etiology Motor Vehicle Accident Fall Sport injuries Vigorous Exercise Bone Diseases Osteoporosis Osteomyelitis Cyst, …
Types of Fracture Ordinary Caused by a force Normal bone Pathological Caused by trivial force Diseased (weak) bone
Types of Fracture Ordinary Caused by a force Normal bone Pathological Caused by trivial force Diseased (weak) bone Osteoporosis Osteomyelitis Tumour, cyst,..
Types of Fracture Incomplete Fracture line is incomplete Only one cortex is broken Complete Fracture line is complete Bothe cortices are broken
Types of Fracture Incomplete Green-stick One cortex is broken Other cortex is bent In children Lee P et al. Radiographics 2004;24:
Types of Fracture Complete Simple: One fracture line Two bone fragments Comminuted: More than one fracture line More than two bone fragments More soft tissue injuries
Types of Fracture Complete Simple: Hairline (Fissure) In repeated stress e.g. march fracture in metatarsals Transverse Oblique Spiral
Types of Fracture Complete Comminuted: Butterfly Segmental Multiple fragments Compression
Types of Fracture Undisplaced Normal alignment maintained Displaced Deformed from normal alignment
Types of Fracture Closed Skin intact Compound (Open) Skin not intact Communicating to outside
Types of long bone fractures Metaphyseal Diapyseal Articular Epiphyseal (children)
Sign and Symptoms of Fracture Pain Swelling Deformity Local tenderness Loss of function
Diagnostic Evaluation X-ray The most useful MRI, CT-scan In suspected cases In intra-articular fractures
Fracture Healing Stages of fracture healing: Hematoma Inflammation Repair Remodeling
1. Hematoma Bleeding caused by vessel rupture Hematoma collects Bone at fracture edges dies Rockwood and Green
2. Inflammation Inflammatory cells accumulate Inflammatory mediators (cytokines) New blood vessels proliferate Rockwood and Green
2. Inflammation Mesenchymal cells accumulate After 1 week forms granulation tissue Osteoclasts remove necrotic bone at fragment ends growth factors stimulate the proliferation and differentiation of mesenchymal stem cells Formation of connective tissue
3. Repair Connective tissue differentiates Cartilage and fibrous tissue form Soft callus formation (2-3 weeks) Movement at fracture stimulates more callus Rockwood and Green
3. Repair - Tissue Differentiation connective tissue granulation tissue Giemsa stain
3. Repair Vascular and cellular response leads to tissue differentiation and mineralization resulting in restoration of mechanical integrity Fibrocartilage mineralizes (converts callus to woven bone)
Tissue Differentiation Cascade Cartilage formation Bone Mineral deposition Masson-Goldner
Callus Formation Periosteal callus forms along the periphery of the fracture site Intramedullary callus forms in the center of the fracture site Endochondral ossification at the site of the fracture hematoma Chemical and mechanical factors stimulate callus formation and mineralization
Callus Formation Stability adequate in axial plane Angulation can still occur fracture ends linked together by soft callus hard callus stage starts & lasts until fragment ends are firmly united by new bone (3-4 m) Rockwood and Green
4. Remodeling Woven bone slowly replaced by lamellar bone (few months to years) Medullary cavity is reconstituted Bone is restructured in response to stress and strain
Fracture healing - summary 1. Inflammation Hematoma Mesenchymal cells 2. Soft callus Granualation tissue Fibro-cartilage 3. Hard callus Intramembranous bone formation Enchondral ossification 4. Remodeling bony bridging
Fracture healing - summary Summary
Prerequisites for Bone Healing Adequate blood supply Adequate mechanical stability If either is lost: results in delay in bone healing or no healing occurs Smoking causes delay in bone union or nonunion
Complications of fractures Early: Shock Compartment syndrome Fat embolism Deep vein thrombosis, embolism Infection Delayed Malunion Delayed union / Nonunion
Complications of fractures Shock loss of blood Fractured femur could bleed 2L easily Fractured Pelvis could bleed 4L easily Open fractures with vascular injuries What is the normal blood volume? How much bleeding could be tolerated?
Complications of fractures Compartment syndrome The compression of nerves, blood vessels, and muscle inside a closed body space (compartment)compartment Causes tissue death from lack of oxygenation due to the blood vessels being compressed by the raised pressure within the compartment More common in Forearm and leg (why?)
Complications of fractures Deep Vein Thrombosis, Embolism Caused by Increased pressure in compartment Interrupted venous return Hematoma
Complications of fractures Infection: More in open fractures Depends on amount of contamination and tissue necrosis Possible in closed fractures
Complications of fractures Delayed Malunion: deformity Delayed union Non-union
Management of fractures First aid: ABC Other injuries Cover wounds Bone immobilization Definitive treatment of fracture
Management of fractures Assessment Type, location and severity of fracture Soft tissue damage Age and health status of patient Affection of other parts or organs
Management of fractures Goals: To regain and maintain correct position and alignment. To regain the function of involved part. To return the patient to usual activities in the shortest time and at the least expenses.
Definitive treatment of fractures Conservative Simple fractures More in children Operative More complex fractures Articular fractures More in adults
Conservative - closed reduction Is the most common non surgical method for managing a simple fracture. Splints: as upper extremity bones do not bear weight, splints may be sufficient to keep bone fragments in place.
Conservative - closed reduction Casts : A cast is an immobilizing device made up of layers of plaster or fiber glass. Allows early mobility and reduces pain
Conservative - closed reduction Traction: Application of a pulling force to a part of the body Uses a system of ropes, and weights to provide reduction, alignment and rest
Open reduction / internal fixation Achieves perfect reduction Permits early mobilization It is often preferred for elderly patients who are susceptible complications of immobility Best for adults and in intra-articular fractures Uses pins, screws, rods, plates,.. After bone union, the metal may be removed, depending on the location and type of fracture
Examples of internal fixation Screws Wires Nails
Open reduction, internal fixation Forearm fractures in adults (Plates)
Nail in Tibial Fractures Intramedullary Nail
Plate for comminuted Femur fracture
Intra-articular fracture
External fixation Ideal for open fractures where wound care is needed and operation is hazardous Often used temporarily until wounds recover Image from C. Turen MD
External fixation Nail later
Summary What is a fracture Types of fractures Fracture healing and requirements Management
Rockwood and Green