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- 1. AOTrauma Principles Course Fracturefixation using the locking compression plate (LCP) Michael Wagner, AT
- 2. Learning outcomes • Understandthe different functions of conventional and locking head screws. • Understand the different concepts of fracture fixation using locking compression plates. • Apply the principles to clinical usage—“know when which principle needs to be applied in a clinical example”. • Understand the advantages of locked plates in special clinical circumstances (eg, osteoporosis).
- 3. Locking compression plate(LCP) dynamic compression unit conical and threaded unit
- 4. Different types ofscrews Conventional screws Cortex screw (with or without shaft) Cancellous bone screw (with or without shaft) Locking head screws (LHS) Self-tapping LHS Self-drilling, self-tapping LHS
- 5. Mechanics/biomechanics of plate/screw fixation Platefixation with conventional screws • Screws in tension • Plate/bone friction • Compression at fracture site • Disturbed blood supply Plate fixation with locking head screws (LHS) • Screws in shear • Noncontact plate • No compression of fracture • Preserved blood supply
- 6. Functions of conventionalscrews (slide 1 of 2) • Plate screw - Preload and friction is applied to create force - between plate and bone • Lag screw - Interfragmentary compression screw; always - inserted before fixation of the plate with LHS • Compression screw (eccentric screw) - Positioned in the dynamic compression unit (DCU) • Position screw - Keeps two fragments in position without - compression
- 7. Functions of conventionalscrews (slide 2 of 2) Reduction screw Screw inserted through a plate hole to pull fracture fragments toward the plate Reduction of a butterfly fragment (no interfragmentary compression)
- 8. Drawbacks of fixationwith conventional screws • Compression of the periosteum and resulting damage of the blood supply to the bone • Primary loss of reduction • Secondary loss of reduction primary loss of reduction secondary loss of reduction
- 9. Functions of lockinghead screws (LHS) • Always in combination with a plate • Never as lag screw • Never cross an unreduced fracture with a LHS • Fixation screw - Fix the plate to the bone • Position screw - Keeps two fragments in correct relative anatomical position
- 10. Features and advantagesof LHS • Axial and angular stability • Not preloaded • Cannot be over-tightened • Higher resistance against bending loads • Monocortical insertion is possible (shaft and good bone quality needed) • No primary loss of reduction • No or less screw loosening, no or less secondary loss of reduction
- 11. Features and advantagesof locked plates • Screw-plate system with angular and axial stability • Locked internal fixator/noncontact plate • Individual blade plate
- 12. Biological advantages • Reducedcompression of the periosteum • Protects blood supply to the bone • Callus formation/bone healing under the plate bone after plating with a DCP bone after plating with a LCP
- 13. Clinical advantages • Osteoporosis •LHS cannot be over-tightened • Higher resistance against bending forces • No secondary screw loosening • Epimetaphyseal fracture/short fragment • Angular and axial stability • No primary loss of reduction • Blade plate • MIPO or less invasive technique • Precise prebending of the plate is not required • No primary loss of reduction secondary loss of reduction primary loss of reduction Technical reason Primary loss of reduction bone necrosis under the plate
- 14. Drawback of fixationwith LHS • Screw insertion is only possible in a 90° angle • No bicortical insertion of self-drilling, self-tapping screws (use self-tapping screws only for bicortical insertion • Possible loss of the feel for the quality of the bone during screw insertion and tightening • Screw jamming and difficult implant removal
- 16. Planning and decisionmaking • The stability of the fracture fixation determines bone healing • How much stability is necessary? Absolute or relative stability • What kind of bone healing is best for the type of fracture? Direct or indirect bone healing • Which are the technical limitations? (eg, iatrogenic trauma) direct bone healing (histological photo) indirect bone healing (x-ray)
- 17. Planning and decision making―influenceof motion Abolish fracture site motion → absolute stability leading to direct healing Factors influencing motion: • Plate properties • Screw properties • Interface properties (coupling) • Fracture site properties Reduce fracture site motion → relative stability leading to indirect healing
- 18. Preoperative planning • Factorsdetermining the method and principle • (grade of stability) of the fracture fixation: • Length of plate and/or shape of plate • Type and function of screw • Position and number of screws
- 19. Characteristics of theLCP system: different sizes and adjusted to anatomy Standard plates Special and anatomically preshaped plates
- 20. Compression with plates Principle= absolute stability Method = compression Technique = conventional plating (ORIF) • Different plate functions: - Protection plate - Compression plate - Buttress plate - Tension band plate • Indications: - Simple fractures (shaft and metaphysis) - Articular fractures - Delayed union or nonunion (same use as the LC-DCP)
- 21. Compression with plates—prerequisites •Precise anatomical reduction (direct, open) • Stable fixation with interfragmentary compression • Good bone quality • Exact prebending of the plate
- 22. Tibial shaft fracture,42-A1 53-year-old man, skiing injury Principle: absolute stability Method: interfragmentary compression Technique: conventional plating (ORIF) first step preoperative x-rays postoperative x-rays follow-up x-rays Case from Christian Ryf, Davos
- 23. Closed forearm fracture,22-B3 17-year-old man, soccer injury 1. 1. 3. 2. Principle: absolute stability Method: interfragmentary compression Technique: conventional plating (ORIF) preoperative x-rays postoperative x-rays Case from Emanuel Gautier, Fribourg clincal picture of plate insertion
- 24. Closed radial shaftfracture, 22-A2 (slide 1 of 2) 25-year-old man, fall on arm Principle: absolute stability Method: interfragmentary compression Technique: conventional plating (ORIF) preoperative x-rays postoperative x-rays Case from Michael Wagner, Wien clincal pictures of plate insertion
- 25. Closed radial shaftfracture, 22-A2 (slide 2 of 2) 25-year-old man, fall on arm Case from Michael Wagner, Wien follow-up x-rays and clinical pictures 6 weeks postoperatively
- 26. Articular multifragmentary tibialhead fracture, 41-C3 (slide 1 of 2) 19-year-old woman, fall from horse Principle: absolute stability Method: interfragmentary compression Technique: conventional plating (ORIF) Case from Michael Wagner, Wien preoperative x-rays, AP and lateral view CT scan in sagittal plane CT scan on frontal plane
- 27. Articular multifragmentary tibialhead fracture, 41-C3 (slide 2 of 2) 19-year-old woman, fall from horse Case from Michael Wagner, Wien postoperative x-rays follow-up x-rays after 1 year
- 28. Splinting with plates Principle= relative stability Method = splinting/locked splinting Technique = less invasive or MIPO, following indirect reduction • Plate functions: • Bridging plate with conventional screws • Locked internal fixator • Indications: • Multifragmentary metaphyseal/diaphyseal fractures • Osteoporosis • MIPO
- 29. Splinting with lockedplates— prerequisites • Indirect, closed, no precise reduction • Long plate • Fixation with LHS only on main fragments • No screws in fracture zone • Prebending of plate not necessary • Elastic fixation to achieve relative stability
- 30. Splinting with lockedplates—features and advantages • Biological • MIPO > soft-tissue preservation • Locked elastic fixation: relative stability > callus formation • No or minimal contact of the plate to the bone > undisturbed blood supply • Monocortical LHS in the diaphysis preserve: - medullary blood circulation - distant cortex - adjacent soft tissues • Technical/mechanical • No need of exact anatomical preshaping of the plate • No primary loss of reduction • Angular and axial stability of screws > less screw loosening • Note: the plate takes over the entire load
- 31. Splinting with lockedplates— shortcomings and disadvantages • Stability of the fixation depends on the rigidity of the construct • Plate takes over the entire load • MIPO is a demanding/difficult technique (closed indirect reduction)
- 32. Multifragmentary distal femoralfracture, 33-A3 (slide 1 of 2) 87-year-old woman Principle: relative stability Method: locked splinting Technique: MIPO preoperative x-rays postoperative x-rays after bridging of the multifragmentary fracture with a minimally invasive approach. follow-up x-rays Case from Christoph Sommer, Chur
- 33. Multifragmentary distal femoralfracture, 33-A3 (slide 2 of 2) 87-year-old woman postoperative x-rays after 3 months clinical pictures after 3 months follow-up x-rays after 5 months Case from Christoph Sommer, Chur
- 34. Combination of compressionand splinting with one plate • A combination of both methods is only possible when two different • fractures occur in the same bone. • Indications • Segmental fractures • Articular fracture with additional metaphyseal/diaphyseal fracture • Note: never combine the methods in one fracture!
- 35. Multifragmentary proximal tibialfracture, 41-C2 83-year-old woman (with osteoporosis), hit by car as pedestrian Articular fracture Principle: absolute stability Method: interfragmentary compression Technique: conventional plating (ORIF) preoperative x-ray follow-up x-rays after 6 months follow-up x-rays after 1 year Case from Michael Wagner, Wien postoperative x-ray Multifragmentary metaphyseal fracture Principle: relative stability Method: splinting Technique: MIPO
- 36. Open tibial shaftfracture, 42-C2 (slide 1 of 2) 50-year-old man, skiing injury Simple metaphyseal fracture Principle: absolute stability Method: compression Technique: ORIF preoperative x-ray reduction and fixation postoperative x-rays Case from Christian Ryf, Davos Multifragmentary shaft fracture Principle: relative stability Method: locked splinting Technique: less invasive
- 37. Open tibial shaftfracture, 42-C2 (slide 2 of 2) 50-year-old man, skiing injury follow-up x-rays after 6 weeks follow-up x-rays after 6 months Case from Christian Ryf, Davos follow-up x-rays after 8 months indirect bone healing direct bone healing
- 38. Summary/take-home message • Twodifferent methods and principles: - compression—absolute stability - splinting—relative stability • Essential points for correct practical application: - preoperative planning - no mixture of principles/methods in same fracture
- 39. Summary/take-home message • Compressionplating after anatomical reduction in articular and simple fractures. • Splinting/bridge plating in multifragmentary fractures to minimize amount of additional trauma (MIPO). • Locking head screws always with locking compression plates; better fixation, convenient in osteoporosis, technical and biological reasons.