1. DISCUSS THE PRINCIPLES AND
RECENT ADVANCES IN THE
INTERNAL FIXATION OF
FRACTURES.
PRESENTER; DR OGBOJI OBINNA,E
MODERATOR; DR RC EZEH.
CHIEF CONSULTANT ORTHOPAEDIC SURGEON

2. OUTLINE
 Learning objectives
 Introduction
 Historical perspective
 Biology of bone healing
 Indications
 Contraindications
 Principles
 Preoperative evaluation
 Intraoperative measures
 Postoperative care
 Complications
 Advances
 Loco-regional challenges
 Conclusion

3. LEARNING OBJECTIVES
To understand the principles guiding the internal
fixation of fractures.
To understand the biomechanics of implant.
To note the advances made in the use of internal
fixation in management of fractures.

4. INTRODUCTION
 Internal fixation of fractures is the internal retention of a
reduced fracture segment(s) with an implant for bone healing.
 This a modern technique & an advancement in fracture
management
 A good understanding of the principles is key to a good
outcome and minimal morbidities.

5. INTRODUCTION CONTD
 Implants provide a temporary support, maintain alignment
during the fracture healing and allow for a functional
rehabilitation
 This method of fracture treatment aims to avoid fracture
disease due to prolonged immobilization in fracture
management

6. Introduction Contd
Successful application of internal fixation
depends on:
• Appropriate indication
• Observance of correct biomechanical principles
• Strict aseptic technique
• Surgical technique

7. HISTORICAL PERSPECTIVE
 Fixation of bone fracture using an iron wire was reported for
the first time in a French manuscript in 1775.
 Use of cerclage wires to fix fractures was developed towards
the end of the 18th century.
 The first internal fixation by means of a plate and screws was
described by Carl Hansmann in 1858 in Hamburg.

8. HISTORICAL PERSPECTIVE
Arbuthnot Lane (1892) and Albin Lambotte
(1905) are considered to be the founders of
this method [plate and screws], which was
further developed by Sherman in the first part
of the 20th century.

9. Robert Danis (1880 to 1962). Introduced the term of
soudure autogéne [autogenous welding]

10. HISTORICAL PERSPECTIVE CONTD
Maurice Müller founded
the
Arbeitsgemeinschaft für
Osteosynthesefragen
(AO) 1958

11. Gerhard Küntscher(1900-1972)
Developed the technique of IM Nailing

12. Goals of Internal fixation
Full restoration of function
Early return to his preinjury state
Minimize the risk and occurrence complications
Predictable alignment of fracture fragments

13. BIOLOGY OF FRACTURE HEALING
INFLAMMATION
SOFT CALLUS FORMATION.
HARD CALLUS FORMATION
REMODELLING

14. Biology of Fracture Healing
 IMPORTANT NOTICE:
Every fracture is a soft tiidue injury where the
bone happens to be broken.
For a fracture union, there should be a certain degree
of immobilization, optimally preserved blood
supply and appropriate biological or hormonal
stimuli

15. BIOLOGY OF FRACTURE HEALING.

16. Impact of Internal fixation on fracture
healing
Anatomic reduction and stabilization of fracture by
internal fixation alters the biology of fracture healing.
Two types of stability are possible:
Absolute
Relative

17. STABILITY OF INTERNAL FIXATION
ABSOLUTE STABILITY
No movement at fracture site
No or little callus formation
Direct bone healing
Achieved by interfragmentary
compression
Implants: lag screws, compression
plate, tension band
Required in intra-articular fractures
RELATIVE STABILITY
 Movement at the fracture site
 There is callus formation
 Indirect bone healing
 No interfragmentary
compression
 Implants: Bridge plating,
intramedullary nails
 Required in diaphyseal
fractures

18. Impact of fixation on Fracture Healing

20. Biology of Bone healing

21. Strain theory of fracture Healing
 Described by Prof. Stephan M. Perren
 Strain: change in fracture gap divided by fracture gap [∆L/L]
 Mechanical stability determines the strain at the fracture site
 Strain <2% = Primary bone healing
 Strain 2% -10% = Secondary bone healing
 Strain >10% = Nonunion

22. Indications For Internal Fixation
Inherently unstable fractures
Displaced intra-articular fractures + forearm
fractures
Pathological fractures
Multiple bone fractures [Polytrauma]

23. Indications For Internal Fixation of fractures
Open fractures
Associated neurovascular injury
Failed closed treatment
Nonunion and malunion
Fractures in patients who present nursing difficulties
eg paraplegics

24. Contraindication(s)
Fasciotomy for fractures complicated with
compartment syndrome
Active infection.
Inadequate equipment, manpower, training,
and experience

25. IMPLANT USED FOR INTERNAL FIXATION
Pins, wires and
screws
Plates
Intramedullary nails
Biodegradable
implants

26. General characteristics: implant
materials
Stainless steel (Iron, chromium and Nickel)
Good tensile strength and high resistance to
corrosion
Relatively inexpensive, and strong.
Titanium:
Pure Titanium (titanium and 02)
Alloy (Titanium, Vanadium and aluminium)

27. Implant Materials
Cobalt – Chromium alloys
Most recently: Biodegradables materials like
polyglycolic acid, polylactic acid & polydioxanone

28. K-WIRES AND PINS
Kirschner wires(0.6 – 3mm) and Steinmann pins(6-
3.0mm) are available for provisional fixation of
fractures.
K wires can be indicated for:
Fractures in epi-/metaphyseal areas
Fractures of small bones (eg, hand and foot)
Small bony fragments
For fragment reposition in multifragmentary
fractures in addition to stable fixation

29. Factors that influence the size of the K-wire
 Patient age/weight
 Fracture location; small bones (hand
and foot) require 1.0–1.6 mm K-wires.
 Fragment size
 K-wire trajectory; fractures fixed with
two (or three) K-wires from only one
side, one size larger K-wires are used
than for bilateral crossed K-wiring

30. TECHNIQUE OF K-WIRING
Entry point :from free
fragment into the main
fragment
Cross the fracture line far apart
Not cross around or before the
fracture

31. TENSION BAND WIRING
Here tensile forces distracting
the fracture are absorbed by the
wire and converted into
stabilizing compression forces
Useful olecranon, patella,
greater trochanter, tuberosity,
lateral malleolar fractures,

32. SCREWS
Converts rotation into linear motion
Named according to design or function
Design
Partially vs fully threaded
Cannulated vs non-cannulated
Self-tapping vs non-self tapping
Cortical vs cancellous
Others: locking head screw, malleolar screw
Function
Lag screw
Position screw; syndesmotic screws
Hold plate attached to bone

33. Method of Screw Fixation
Preliminary drill hole with
drill bit through drill guide
and drill sleeve
Screw depth is measured
The drill hole is tapped
Screw is driven by a
screwdriver

34. Screw types

35. Self-drilling vs self-tapping screws

36. Lag screw
 The drill bit corresponding to the
major diameter is used for drilling the
gliding [near] hole for a lag screw
 The drill bit corresponding to the
minor diameter is used for drilling the
threaded [far] hole.
 Screw perpendicular to fracture line
and equidistant from the fracture
edges
 Achieves interfragmentary
compression

37. Lag screw through a plate

38. PLATES
Functions
 Protection or Neutralization
 Buttress
 Bridge
 Compression
 Tension band
Designs
 DCP, LC-DCP
 Angle blade plate
 T an L-plates
 Tubular, Anatomic plates
 Reconstruction plate
 Locking plate / LCP

39. Plate contouring
Plates applied towards the
metaphysis requires
contouring due to flaring of
this region in these regions
usually need to be
contoured.
The use of a flexible template
can facilitate plate
contouring.
.

40. Anatomic plates
Distal tibia
Proximal tibia
Distal humeral
Distal femur
Fibula
Olecranon
Clavicle

41. Protection or Neutralization plates
Protects the lag screw fixation from
all torsional, bending and shearing
forces
Lag screw fixation alone is not able
to withstand much loading

42. Buttress plates
 Serves to prevent axial deformity
as a result of shear
 Applied to the area or cortex
which has been broken and which
is coming under load
 Must be firmly anchored to the
main fragment
 Must also correspond very
accurately to the shape of the
underlying cortex or a deformity
could ensue

43. Buttress Plating
 Used to supplement lag screw fixation
of metaphyseal shear or split fractures
in the metaphyseal regions.
 The lag screws may be inserted either
through or outside of the buttress
plate

44. Bridge plating
 Here the plate serves as an
extramedullary splint fixed to the two
main fragments, while the complex
fracture zone is bridged
 Restores axial alignment, length and
correct rotational alignment of the
main shaft fragments.
 Relative mechanical stability,
provided by the bridging plate, leads
to healing by callus formation.

45. Compression plating
 Produces compression at
the fracture site to provide
absolute stability
 Some gapping of the far
cortex if plate is contoured
exactly to the anatomically
reduced surface

46. COMPRESSION PLATING
 It is important to “over-
bend” the plate so that its
center stands off 1-2 mm
from the anatomically
reduced fracture surface.
 The over bend should lie
directly over the fracture
line.

47. Articulated tension device
 Used to provide mechanical
compression prior to fixation with
screws
 The device may also be used to
create distraction.

48. Tension band fixation
 Compression plate is
applied on the tension side
 Converts tension force to
compression force
 Achieves absolute stability
 No comminution on the
compression side
 Pre-bend plate

49. Locking plate
 Provides angular stability
 Indicated in osteoporotic bone
 The locking plate has a
corresponding threaded plate
hole
 Designs; combi, reconstruction,
anatomic plates

50. Locking plate contd
 During insertion the locking
head screw engages and
locks into the threaded
plate hole.
 The threaded plate hole
also accepts non locking
screws, which permit
greater angulation.

51. Locking plate; advantages [reduced
interference to blood supply]

52. Locking plate; advantages [Biomechanics-load
transmission, reduced friction, high
mechanical stability]

53. Locking plate; advantages [no primary loss
of reduction]

54. Locking plate; advantages [no secondary loss of
reduction as screw loosening is very rare]

55. Angle blade plates [proximal and distal
femur]

56. Angle blade plates [proximal and distal femur]
Advantage of the fixed angle is the increased strength and the
increased corrosion resistance
Disadvantage is the increased difficulty of insertion.
Proximal femur
Blade has to be inserted in the middle of the femoral neck
and at a predetermined angle to the shaft axis
Plate portion of the angled blade plate has to be inserted so
that it will line up with the axis of the shaft at the end of the
procedure

57. DISTAL FEMUR
Blade has to line up with the joint axis and with the
inclination of the patellofemoral joint and be inserted
exactly into the middle of the anterior half of the femoral
condyles at a predetermined distance from the joint
Plate has to line up with the axis of the femoral shaft
Preoperative plan, including a preoperative drawing is
essential

58. Dynamic hip screw plate
 For proximal femoral
fractures

59. Dynamic condylar screw plate
Angle between plate
and barrel is 95o
For distal femoral and
intercondylar fractures
May be used for some
proximal femoral
fractures

60. How many cortices of screw purchase on
each side of the fracture?
 Humerus  six
 Radius and ulna  five
 Femur  seven
 Tibia  six
 Osteoporosis depending on its severity will require a corresponding
increase in the number of screws.

61. Intramedullary nailing
 Well-suited for the mid diaphyseal
fractures
 Stability is increased with the
reamed technique, because the
nail fits tightly in a longer portion
of the shaft
 Types
Centromedullary
Cephalomedullary
Condylocephalic

62. IM NAILING
 Modern IM nails permit
placement of locking
screws through bone and
nail, to improve fixation
both proximally and distally.
 Locked nails permit stable
fixation which controls
length, rotation, and
alignment of proximal and
distal fractures

63. Centromedullary nail
Used for diaphyseal
fractures

64. Proximal femoral nail [cephalomedullary
nail, gamma nail]
Used in proximal
femoral fractures

65. Condylocephalic nail [Flexible nails]
Used in children

66. IM NAILING
Load-sharing device which permits load-bearing
across the fracture site
Choice of nail length; indirect vs direct [with
reaming rod]
Reaming vs not reaming
Locking; proximal and distal locking.
Distal locking done first

67. IM NAILING
 The best method to manipulate distal fragment [if needed]
after distal locking is to use the insertion handle from the
proximal end.
 Compression of the fracture area by proximal tension may be
useful, either by distractor or manually by means of the
insertion handle
 Dynamic locking vs Static locking

68. Principles of internal fixation. Muller et al [1958]
Anatomical reduction of the fracture fragments, particularly in joint fractures.
Stable internal fixation designed to fulfill the local biomechanical demands.
Preservation of the blood supply to the bone fragments and the soft
tissue by means of atraumatic surgical technique.
Early active pain-free and safe mobilization of muscles and
joints adjacent to the fracture, preventing the development of fracture disease

69. AO Principles of internal fixation

70. Anatomic Reduction
Aims of reduction;
To restore the bony anatomy and morphology
[perfect or anatomic reduction]
To restore the relationship between the proximal
and distal main fragments including length,
alignment and rotation [functional reduction]
Methods; Closed [indirect] vs Open [direct]

71. What Reduction Must Achieve?
Diaphysis
Satisfactory restoration of axial alignment in all
three planes (frontal, sagittal, and horizontal)
Displacements should be completely corrected in
young adults and active individuals
Not at the expense of the vascularity of the bone

72. METAPHYSIS & EPIPHYSIS
 Metaphyseal fractures frequently requires buttressing and
cancellous bone grafting for support and to replace bone
lost through impaction of the joint surface into the underlying
cancellous bone.
 Epiphysis is the articular segment of the bone and in this area
absolute anatomic restoration is mandatory

73. Closed [indirect] reduction
• Achieves functional
reduction
• Image-guided
manipulation
 Joystick
 Bone distractor
 Traction table

74. Open [direct] reduction
Achieves anatomical
reduction
Bone holding clamps
Bone reduction clamps

75. Atraumatic surgical technique
Evaluation of limb swelling
Staged procedure to allow soft tissue care
 Primary stabilization → external fixation
 Secondary stabilization → definitive fixation
 Care of soft tissue injury; Debridement, irrigation, wound
cover
 Careful reduction procedure; Gentle soft tissue handling
 Minimal invasive surgical approaches

76. Early and safe mobilization
Range of motion exercises
Muscle-strengthening exercises
Weight-bearing; partial to full weight bearing

77. Preoperative evaluation
 Resuscitation; ATLS
 Good history
 Age, sex, occupation
 Mechanism of injury
 Duration
 Open wounds
 Associated injuries
 Co-morbidities
 Drugs; Anticoagulant
 Smoking, alcohol
 Initial care; ?TBS
 Clinical examination
General examination
Look; swelling, wasting,
deformity, length discrepancy
Feel; tenderness, crepitus,
distal pulses, sensation
Move; abnormal movement,
muscle power, range of
motion
Other systems

78. INVESTIGATIONS
Imaging; xrays, CT scan,
MRI
FBC + ESR
Urinalysis
SEUC
Clotting profile
Blood grouping and
cross matching
ECG
Patient optimization
Thromboprophylaxis
Informed consent

79. PRE-OPERATIVE PLANNING
 Method of fixation
 Choice of implant
 Surgical approach
 Use of bone graft
 Templating; Direct overlay
vs Planning from the
normal side
 Preoperative drawing
 Staging of the procedure
 Ensure functional
equipment

80. INTRAOPERATIVE MEASURES
 Antibiotics prophylaxis
 Anaesthesia; Regional vs
General
 Positioning
 Tourniquet
 Thromboprohylaxis
 Minimal access
 Image-guidance
 Maintain asepsis
 Atraumatic dissection
 Reduce and maintain
reduction
 Drain vs no drain
 Layered wound closure
 Adequate wound dressing

81. POSTOPERATIVE CARE
 Postop check x-ray
 Pain management
 Thromboprophylaxis
 Physiotherapy; ROM
exercises, chest
 Early mobilization
 Nutritional support
 Wound care
 Suture removal
 Discharge
 Follow-up
Serial x-rays to assess
bone healing
Implant removal

82. COMPLICATIONS
Early
Vascular injury
Nerve injury
Muscular injury
Compartment
syndrome
Late
Non union
Malunion
Refracture
Implant failure

83. ADVANCES IN INTERNAL FIXATION OF
FRACTURES.
BIODEGRADABLE IMPLANT
 Currently on design/redesign
 Absorbable suture material
polymers like polylactic,
polyglycolic and polydiaxone
 Design into rods or screws

84. BIODEGRADABLE IMPLANTS
ADVANTAGES
 Eventual resorption.
 No need for removal
 Allows stress transfer to
remodeling fracture
DISADVANTAGES
 Defective mechanical
property
 Limited indications
 Requires protected weight
bearing
 Local inflammatory
reactions, chrondrolysis.

85. Advances
Point contact fixator
Optimal preservation
of blood supply
 Enhanced fracture
healing
 Improved resistance
to infection

86. Advances
Telescopic
intramedullary nail
For bone
lengthening

87. MINIMALLY INVASIVE PREOCEDURES
MIPPO; minimally invasive percutaneous plate
osteosynthesis
LISS; less invasive stabilization system
CRIF; closed reduction internal fixation e.g closed IM
nailing

88. Minimally invasive percutaneous plate
osteosynthesis [MIPPO]

89. LESS INVASIVE STABILIZATION
SYSTEM(LISS)
 The LISS plate is an internal fixator
designed as an extramedullary
splint.
 Fixed to the two main fragments
using minimally invasive techniques
leaving the fracture haematoma
intact
 Non union rates are high if there are
gaps left

90. Locoregional challenges
Ignorance
TBS care
Poverty
Poor infrastructure; limited choice of implant, scarcity
of image intensifie.

91. TAKE HOME MESSAGE
 Internal fixation of fractures is an important tool for modern
Orthopaedic practice.
 A good knowledge, good choice and proper application of
the implant is key for a good outcome.
 Advances have been made in the design and redesigning of
these implants to solve various challenges of fracture
management and to improve outcome

92. Conclusion
 Internal fixation of fracture is a very common procedure in orthopaedic
practice
 Good understanding of the principles is essential in deciding which
method to use out of the many methods that exit for specific types of
fractures to avoid complications
 Often times we are limited by the skill and/or implant available in our
place of practice
 Continuous efforts in training and re-training of surgeons is important for
good outcome

93. References
 Dr Praveen Principles of internal fixation Powerpoint presentation
 https://www.orthobullets.com/basic-science/9009/fracture-healing
 Josefa Bizzarro, Pietro Regazzoni. Principles of fracture fixation. AO Trauma
 https://surgeryreference.aofoundation.org
 M. E. Muller, M.Allgower, R. Schneider, H. Willenegger. Manual of INTERNAL
FIXATION. 1991. 3rd Edition
 Dr Anikwe IA. Discuss the principles of internal fixation of fracture. Powerpoint
prresentation
 Dr Uchendu T,U:Discuss The Principles of Internal fixation of fractures:Power point
presentation.

94. THANKS FOR KIND ATTENTION