all orthopaedic implant evolution has been discussed in detail

1. MODERATOR
DR D N BORAH
ASST PROFESSOR ,
DEPARTMENT OF ORTHOPAEDICS ,GMCH
PRESENTED BY
DR VIKASH JHA
PGT ORTHOPAEDICS

2.  Earliest Examples Of Active
Management Of Fracture Was
Discovered In Egypt, By Professor,
G. Eliiot
 Two Specimen with Splinted
Extremities , One Compound
Fracture Femur In An Adolescent,
 Other Specimen Was Of Open
Fracture Of Forearm ,
 Victims are Judged To Have Died
Shortly After Injury, As Bones
Show No Evidence Of Healing
Reaction

3. Basic terms
 Implants are devices or tissues that are placed inside or on the
surface of the body
 ORTHOSES- Externally applied device to correct bio mechanical
alignment
 Many implants are prosthesis, intended to replace missing body
parts
 Stiffness – resistance of structure to deformation
 Rigidity –physical property of resisting deformation under load
 Elasticity –ability of a material to recover its original shape after
deformation
 Plasticity –ability of a material to be formed to a new shape
without fracture and to retain that shape after load removal
 Ductility – ability of solid material to be deformed under tensile
stress an to be streched into wire without fracture

4. Metals and implants in orthopaedics
 Early fracture surgery
1. Wire fixation –A.M.I-
CART 1770s surgeon of the
HOTEL DEAU AT CASTRES
2. Bone suture -1827 DR
KEARNY RODGERS OF NEW
YORK , resected pseudo
arthosis humerus
3. The 1st book published
on internal fixation
“traite de
immobilization” by
BERENGER

5.  Screw fixation –(works by CONVERTING rotational force
into linear motion) use of screw in bone probably started in
late 1840s, Cucuel & Rigaud , the french surgeons., described
two cases
 In 1st case , screw was inserted to permit traction on a
depressed fracture of superior part of sternum & elevate the
fragment
 2nd case he inserted TWO screws in ulna and olecranon,
wired them together,achieving satisfactory union using
MACHINE SCREWS
 Sherman advocated self-tapping, fully threaded vanadium
machine screws instead of the customary tapered soft-steel
screws that were intended for use in carpentry

6.  Robert Danisproposed 3 key
screw design features tailored
specifically to bone
 A ratio of exterior diameter to
core diameter of 3:2, not 4:3 as
is typical of metal screws
 A reduction of thread surface
area to one-sixth that of metal
screws because bone is
approximately one-sixth the
strength of metal
 A buttress thread design to
replace standard V-shaped
threads because buttress
threads had greater holding
power.

7. AO FROM 1960 HAS INVENTED THE
FOLLOWING SCREW TYPES
 CANCELLOUS SCREWS–
1)cannulated and non cannulated
2)fully threaded and partially threaded
 CORTICAL SCREWS
 TAPPING & NON-SELF TAPPING
 CORKSCREW TIP(cancellous screw & TROCAR
TIP(malleolar screw)
 SPECIAL SCREWS
• HERBERT SCREW
• ACUTRAK SCREW SYSTEM

8. •Before advent of antiseptic surgery
by Lister,1840 ,surgeons were using
hooks and pins made of various
metals , gold ,silver, platinum or iron
to manipulate and hold fracture
fragments in position
• Bell in 1804 used silver coated
steel pins and noted corrosion in
them
• Lavert in animal experiment found
platinum to be most inert but too
soft for clinical use
•LORD LISTER himself was one of
the 1st to successfully wire a fractured
patella using silver wire

9. PLATE FIXATION
•The first account of plate fixation was by
HANSMAN of hamburg 1886,
• He illustrated a malleable plate, the end of plate
being bent through a right angle to project through
the skin ,
• He described this use in 15 fresh fractures and 4
pseudoarthoses
• his implants were made of NICKEL PLATED SHEET
STEEL, SINCE CORROSION OF IMPLANTS WAS
WELL KNOWN THEN , the plate was fixed to bone by
ivory pegs and removed 3 -4 weeks later

10.  George guthrie used the same techniques in 1903,
 He also used rubber gloves during the surgery, seemingly
antedating the reputed 1st use of gloves by HALSTEAD.
 ALBIN LAMBOTTE coined the term Osteosynthesis , & is
generally regarded as father of MODERN internal fixation
 Lambotte , developed not only plates and screws but
external fixation devices similar in principle to ones in use
today

12. SIR WILLIAM ARBUTHNOT LANE
• A BRITISH SURGEON , he was the early pioneer
who placed plate and screw fixation on sound
footing
• He devised plates that were made of STOUT STEEL,
a high carbon steel of fairly high percentage of
carbon
• He deviced NO TOUCH TECHNIQUE, to prevent
wound infections, and his own results bear
testimony of his great skills
• However his implants used to be brittle and broke
at junction of central bar and 1st hole

13.  Lane performed open reduction and internal fixation in all
cases of simple fracture
 Internal fixation of compound fractures were universally
failure, but no case of operated simple fracture became
infected
 This was path breaking, LANE was using LISTER’S antiseptic
technique
 Using long mackintoshes upto the neck wet with carbolic or
lysol during surgeries
 Lane is also credited for developing NO TOUCH
TECHNIQUE of bone surgery

14. A) LANE BENT WIRE
B) CORRUGATED STEEL
STAPLES
C) SCHEDE BRUN PLAIN
STEEL STAPLES
D) LAMBOTTE GOLD
PLATED BONE SPIKES
E) LAMBOTTE SCEWS
FOR FIXATION OF
FRAGMENTS

15.  LANE also decribed tincture iodine for skin preparation
& draping and skin toweling
 In 1905 illustrated plating, & the use of intramedullary
screw fixation for fractures of neck of femur
 VON BAYER In 1908 introduced pins for fixation of “small
fragments” at intraarticular level
 Most of screws that were used in plating procedure at this
time were derived from SHERMAN’s design , he also
introduced the use of corrosion resistant vanadium steel

16. WILLIAM SHERMAN

18.  Thus rigid anatomic reduction was achieved with use of
plates and screws that compress the bone fragments against
each other .
 A large exposure was required with iatrogenic injury of
muscular and periosteal structure , applying a plate on
the bone invokes delayed union and in some cases non union
 It was demonstrated and spread by Muller , in order for this
result to be accomplished , compressors were used and later
on establishing the principle of dynamic compression(DCP) .
In this way primary bone healing was made possible

19.  DANIS of Belgium in 1940 heralded the modern era of
internal fixation
 he was the 1st to describe PRIMARY HEALING of fracture
 BUT , it caused refractures after the removal of plated
materials , this disadvantage has led to biological
osteosynthesis with plates
 In 1967 SCHENK and WILLENGER showed importance
anatomic reduction and intra fracture compression

20. Special fractures of the hip
 Nails capable of preventing absorption
of the femoral neck and
intertrochanteric line like the three
winged telescoping nail of PUGH , and
the respective screw nail of CHARNLEY
were developed
 Angular nail plates with angles of 130
degrees and 95 degrees ,between U
shaped blade and thick plate were used
 At the same time technology of
Dynamic Hip Screw of RICHARDS was
developed, a method that even today is
approved for treating fracture of the hip

21. For fracture of femoral neck
MACLAUGHLIN SLIDE
PLATE SMITH PETERSON in 1937
introduced the solid
TRIFLANGED NAIL
 JOHNSON modified it to
Cannulated one
 TOURTON &MACLAUGHLIN
separetely used extra plate
attachment for improve fixation
of distal fragment
 JEWETT one piece fixation device
was introduced thereafter
 JEWETT PLATE

22.  The subsequent nails were made
in one piece:
 1)nail similar to Smith-Petersen
nail
 (2) Cannulated nail designed by
Johansson in 1932
 (3) Broad flanged nail of L.
Bôhler with spikes that were
supposed to prevent backing-out
 (4) Felsenreich nail with broad
flanges
 (5) SP-nail with inner threads at
the end;
 (6) Thornton nail made from
vitallium
 Resorption at the fracture site
lead to the shortening of the
neck, the nail often perforated
the femoral head

23.  PUGH Used telescoping nail
to overcome bone resorption
 Similarly, buttressing plates
were used to overcome it, but
it did not prevent a backing
out of the nail
 Next Closed reduction and
cannulated screw fixation
 HRA with Austin moore &
Thompson prosthesis
 Bipolar prosthesis
 THR
 Buttressing plate

24. AO STANDARDISED
INSTRUMENT
SET
 THE AO GROUP
(ARBEITGEMEINTSCHAFT
S FUR
OSTEOSYNTHESEFRAGEN
) was formed in BIEL,
SWITZERLAND by 13
surgeons on november 6th
1958

25. Cornerstones of AO Technique
“Technique of Internal Fixation of Fractures” (1965)
 Rigid compression to achieve primary bone union
 Use of austenitic stainless steel
 Pre-threading of screw holes
 Preservation of blood supply
 Early active mobilization
 1st DCP were introduced in 1972, as a load sharing device
It could provide compression at fracture site – primary healing

26. Biological Osteosynthesis
 The fracture healing is similar to the closed treatment of the
fractures with the creation of callus .
 Devices that provide this possibility are the waving and the
limited contact plates (LC-DCP).
 Metallic body is not in contact with the bone at the fracture
site and the space allows for the autogenous graft placement
 Used in the multifragmentory fractures of the femoral
diaphysis , when there is destruction at the medial cortex

27. 1967- AO
 Rigid fixation by DCP
 Low rate of malunion ,
 Stable fixation ,
 No need for external immobilization ,
 Allowing immediate movements of neighbouring joints.
 LC-DCP represents an improvement of DCP (by PERREN), Due
to its shape it reduced the bone plate contact by 50% ,
 interfragmentary compression is possible

28.  NEXT was the invention of Locking Screws
 Better material attachment
 Screws need to anchor in only one cortex
 In that way, limited contact osteosynthesis
plate in combination with locking and/or
non locking screws could be used
 Eventually, the theory of biologic fixation
lead to the invention of LISS ,(LESS
INVASIVE STABILIZATION SYSTEM)
 An internal locking of that kind maintains
the the advantage of external fixation but
with a potential for final treatment

29.  Main disadvantage
 requires skill during the closed application of the plate and screws .
 In 2001 new plate design developed with Both conventional
cortex screw & angular stable screw called –LCP
 Reconstruction plates (RECON ) with Notched edges to permit
bending ‘on the flat’ as well as conventional bending
 Useful in complex anatomical sites-distal humerus,pelvis
 1990, new system of bioabsorbable nonmetallic materials
became popular,
 PLATES were made of PLA (polygalactic acid) or PGA(Polyglicolic
acid ) or a combination of both PLGA
 Greatest advantage
 progressively absorbed and a second operation for the removal of the
material is avoided

30. Disadvantage
 Reaction of immune system
 Inability to support early mobilization
 So, used in special cases that will not be mobilised early
after their osteosynthesis

31. Intramedullary fixation
 Von Langenbeck, Koenig, Cheyne, lambotte and Lane had
used intra medullary screw fixation for fractures of the neck
of femur
 GILLETE - used intramedullary bone pegs
 Curtis & LANGENBECK, left drill bit in the neck of femur,
while CHARLES Thompson used silver nails in 1899
 Lambotte used the same in fracture of neck of humerus
 In the late 19th century, BIRCHER is credited for using
intramedullary ivory pegs , first used in 1886

32. HEY GROVES LONG STEEL STRUT, 1921
 He was the FIRST to try fixing
fractures of neck of femur by using
round pins introduced through the
trochanter ,
 Round intramedullary rods for fracture
shaft femur
 long metallic intramedullary device
that gripped the endosteal surface of
the bone so called elastic nailing
was the brainchild of GERHARDT
KUNTSCHER

33.  Intramedullary beef & human
bone was used by HOGLUND
 In the late ,1920s SMITH
PETERSON used triffin nail for
the intramedullary fixation of
sub capital fractures of the
femur , which remained the
Standard treatment modality
for 40 years
 Thin solid rods were used by
LAMBRINUDI,1940
 RUSH brothers developed a
system of flexible nails , still in
occasional use

34. Küntscher’s
1st IM
Nailing

35. 1st Generation
 Kuntscher originally used V shaped nail
 Changed to a nail with a cloverleaf cross section for
greater strength
 Can follow any guide wire easily
 His invention was the most significant medical
advance to come out of germany since the discovery of
sulfonamide

36. Advantage
•Solid nail will not occupy the
full width of the medullary
canal in most places
•While K-nail with an elastic
cross section will adjust to the
constrictions of the canal.
• Bone resorption will soon
loosen a solid rod, BUT
• Nail with a compressible
cross section will expand
during bone resorption.

37.  So, Any intervention that included disturbance of the
periosteum lead to delayed healing.
 He also later on developed interlocking femoral and tibial
nails,
 AN intermedullary bone SAW for endosteal osteotomy
 He also developed an EXPANDING NAIL for the tibia
 Developed flexible powered intramedullary reamers

38.  AO group used his
experience to give way
for current generation of
interlocking nailing
system

41. SECOND GENERATION NAILING, 1970
 Reamed nailings were introduced for the humerus and tibia.
 Second generation nailing’s main improvement was the use
of bicortical screw fixation above and below the fracture to
satisfy the requisite control of length and rotation
 Kempf -interlocking nail with welded proximal cylinder for
proximal locking and an image mounted device for distal locking.
 These devices were used in dynamic and static mode
 The Russell–Taylor nail was the first closed section interlocking
nail

42. In 1996, AO - proximal femoral nail (PFN) for unstable
peritrochanteric femoral fractures.

43. THIRD GENERATION NAILING
 1998 to 2008 resulted from an analysis of the failures of
second generation nailing
 In the 1990s, entry portal errors and mal alignment were
the new problems.
 Metaphyseal fractures with inadequate stabilization and
high screw breakage rates .
 Third generation nailing involved a material and
structural change in screw and resulting nail design and
tactical options for screw placement in the
centromedullary design of the nail.

44. • In PFNA lateral cortex impingement in Asian patients has been
reported.
• A second version of PFNA (PFNA-II) was designed with a flattened
lateral surface, decreased mediolateral nail angle, and decreased
proximal nail diameter.
• PFNA-II could avoid lateral cortex impingement while providing
fast and stable fixation of unstable pertrochanteric fractures.
• It has less blood loss, less operative time and less fluoroscopy time.
• When compared to a column screw, use of the helical blade results
in increased contact surface area between the device and the
femoral head cancellous bone, compressing rather than removing
the limited amount of bone.

45. FOURTH GENERATION NAILING
 Combination of the 3 previous generations
 Surface treatments to avoid infection and telemetry to
ascertain the status of bone regeneration and mechanical
reconstitution.
 The two areas of future research are revolving around
different biomaterials and biologically active agents to
promote bone healing.
 Uses biodegradable polymers and Biologically active agents,
such as Bone Morphogenic Protein-2 and 7, have been used
with good success
 These new nails could also be impregnated with slow release
antibiotics to eliminate infections especially in open
fractures.

46. Summary
FIRST
GENERATION
SECOND
GENERATION
THIRD
GENERATION
FOURTH
GENERATION
-Primary splint Locking Screw – Fit anatomical - Surface treatment -
Less Rotational
stability
Improved rotational
stability
Titanium alloy - Telemetry
Logitudinal slot over
entire length
Not Slotted Multi axial screw
fixation – Reaming
Eg- K-nail, V-nail Russel-Taylor Nail
PFN Kempf Nail
PFNA

47. NAILS FOR PROXIMAL FEMORAL FRACTURES

48. EVOLUTION OF IMPLANT METALS
BONE PEGS - 1500
BRASS WIRE- 1775
IVORY ROD 1890
STEEL PLATE (LANE) 1905
SILVER ROD 1913
STEEL ALLOYS 1926
VITALLIUM (STELLITE) 1929
TITANIUM 1950s
CERAMICS 1970
BIODEGRADABLE 1980

49. External fixation
 first documented use of a true external
fixation device dates back to 377 BC by
Hippocrates
 Traditionally 1st external fixation device was the
“pointe metallique” by MALAIGNE
 This apparatus was a hemicircular metal arc
device that could be strapped around the limb
 In 1843 MALAIGNE also described METAL
CLAW , which consisted of of two pairs of
curved points
 This claw was also used at that time to fix
fracture of patella

50.  An ingenious modification
put up by CHASSIN was
proposed in 1852 for use on
displaced fracture of
CLAVICLE
 Parkhill 1894 Threaded pins
and clamp, something that
we use today
 Lambotte used self tapping
threaded pins, rod,
adjustable clamps

51.  Over the few decade, the few
notable devices were of
 CRILE in 1919,
1) drove a peg into neck of femur
via greater trochanter, this peg
bearing externally a metal
sphere
2) A metallic clipper driven into
the condyles of the distal femur
3) And an external linking device
with a universal joint

52. Charnley compression device
•keetley, described an external fixation device
deliberately implanted into the full diameter of
the bone
•In 1931, CONN described an articulated
external linkage device with ball and socket
joint ,
In SWITZERLAND, in 1938 RAOUL HOFFMAN
of geneva, developed an improvised version
of external fixation similar to that used
today
•Charnley 1948 uses his compression device
•In 1966 and 1974,Anderson et al. uses
transfixing pins incorporated into a plaster
cast for management of large series of tibial
shaft fractures and failed miserably
•Till this time all the external fixation relied
on half pins and and single external fixation
device

53.  Dur1970, Axial dynamic external fixation which was more
tolerable by the patients then the VIDAL-ADREY external
fixators
 Walking with full load were made possible by the
micromovement supported fracture healing ,
 In 1960, building on the ground work of HOFFMAN, burny
and bourgois started to outline the biomechanical
principles on which external fixation was based .
 The FIRST FRACTURE APPARATUS using
BILATERAL FRAME & TRANSFIXATION PIN was
used by PITKIN AND BLACKFIELD

54. •EXTERNAL FIXATORS TODAY
• Type -1 Unilateral Uniplanar
•Type -2 Uniplanar Bilateral.
•Type -3
Classical Bilateral Biplanar.
Delta Unilateral Biplanar
•To increase stability of bone –pin
interface
1. Adequate no. of pins in each
fragments
2. Increase pin pitch (3.5mm)
3. Increase size of pin

55. Universal Mini External Fixator
 Micro-motion at
fracture Site.
 It is bi-planar
 More lighter than
traditional External
Fixator.
 More ligamentotasis
 Less chance of pin tract
infections.

56. HYBRID EXTERNAL FIXATOR
 Hybrid Fixator: –
 Thin wires near joint
 Pins (Schanz Screws) in shaft
It Reduces and fix the joint surface
Span the diaphyseal segment without
Disturbing soft tissues

57. MODULAR EXTERNAL FIXATOR & LRS
 These external fixator allows
the surgeon to reduce the
fracture by manipulation and
to hold the reduction.
 Free pin placement allows the
surgeon:
 to spread both pins, thereby
increasing frame stiffness,
 to position pins according to
the fracture pattern or soft-
tissue injury,
 to avoid injury to nerves or
vessels.
 LRS also allows compression
&limb lengthening

58. ILIZAROV RING FIXATOR
 During the 60s GABRIL ILIZAROV developed his circular
osteosynthesis device that since then carries his name and
allowed fixation of fracture fragments and furthermore made
possible the three dimensional re allignment
 Invented in, SIBERIA but in 80s this technique was
introduced into the western world by the ITALIAN surgeon
CARLO MAURI, who was successfully treated by ilazarov for
septic non union of tibia
 Ilizarov found that slow and steady distraction of a recently
cut bone (securely stabilized in external fixator) leads to
formation of new bone within the widening gap

59.  Axially stable tensioned wire circular external fixator
 Using circular external skeletal fixator to distract knee joints
that had developed flexion contractures after prolonged
plaster cast immobilization
 Performed osteotomy through the knee, & gradually
straighten out the limb by turning nuts on the fixator
surrounding his limb.
 One advance in the technique of fixator application consists
of the substitution of titanium half pins for stainless steel
wires in many locations , thereby adding to patients comfort
and acceptance of the apparatus

60. ADVANTAGES
 MINIMALLY INVASIVE
 DEFORMITY CORRECTION
IN 3 DIMENSION
 PATIENT REMAINS MOBILE
DURING TRATMENT
 CAN TREAT NON UNION
 CAN BE USED IN OPEN
FRACTURES

61. THE HIP
 Themistocles Glück led the way in the development of
replacement hip implant design.
 In 1891, he produced an ivory ball and socket joint that he fi
xed to bone with nickel-plated screws.
 Smith-Petersen - first synthetic interpositional
arthroplasty, using a glass prosthesis.
 Glass moulds were prone to breaking,
 Vitallium, a cobalt chrome alloy then recently introduced,
to a mould prosthesis for the hip with first predictable
results in interpositional hip arthroplasty.

62.  Metal-on-metal THR were first implanted in the 1930s,
 In 1970, Boutin developed the first ceramic-on-ceramic total
hip replacement.
 Sir John Charnley’s gave hard on- soft bearing concept that
eventually dominated THR
 Major contributions
 were the idea of low friction torque arthroplasty
 acrylic cement to fix components to living bone
 and introduction of high-density polyethylene as a bearing
material in the artificial joint.
 Charnley had first used Teflon as a low friction surface
material, with spectacular failure
 By a stroke of luck, In 1962 Charnley used UHMWPE (Ultra
high molecular weight polyethylene)

63.  An epidemic of periprosthetic loosening took the orthopaedic
world by surprise.
 Tissue examinations revealed an inflammatory reaction with
macrophages displaying minute particles embedded in them.
Initially these particles were thought to be bone cement, leading to
the erroneous term “bone cement disease” being coined in 1987.
 Ultimately, it was polyethylene wear particles stimulating a
macrophage response,
 So, new direction of UNCEMENTED HIP DESIGNS developed
relied on biologic fixation through osseointegration, independent
of bone cement.
 Implants were developed with porous coatings or a roughened
surface which allowed bony apposition to anchor the implant

64.  Polyethylene degradation– BY OXIDATIVE STRESS
 Gamma radiation traditionally used to sterilise UHMWPE
produces free radicals, which, when combined with oxygen,
produce chain scission
 UHMWPE implants are now gas sterilised by ethylene oxide
 Development of vitamin E impregnated UHMWPE. Vitamin
E is a natural antioxidant that known to be safe and
biocompatible

65.  In 1950s two American orthopaedic surgeons, MOORE and
THOMPSON, had an important impact in this field with the
solution they proposed for the problem concerning the
femoral head.
 They had invented two stable metallic implants that satisfied
the anatomical, mechanical and biological demands of the
hip in a better way
 Those implants consisted of a head a neck and a collar with a
long intramedullary stem with a neck- shaft inclination angle
of 135degree for more natural distribution of forces

66.  Moore-Bohlman Upper
Femur (1941)

67. THA
PRECURSORS
 Moore in 1950 had
designed the
implant with two
portals in the
proximal part of the
stem , which he
filled with grafts of
bone taken from the
femoral head to
achieve desired
stability

68.  Modern era invention of McKee GK OF A STAINLESS
STEEL CUP ON A THOMPSON TYPE HEAD
 This was modified in 1960 by watson farrar with addition
of TEETH like hinges, to gain stability in the acetabulum
 PMMA for the stabilization of implants by SIR
CHARNLEY, MILESTONE IN THR
 1963 polythene was used as a material of friction between
the head and acetabulum
 In switzerland , MULLER, presented his own implant for
hip replacement made of PROTASUL
 THE LOW FRICTION ARTHOPLASTY by CHARNLEY
with a smaller metallic femoral head of diameter 22,225mm
articulated with a polythene cup

69. McKee THA, circa 1940 McKee-Farrar Total
Hip Prosthesis

70.  This method was modified and the lateral approach
with a trochanter osteotomy was replaced by a
 posterior (MOOREs)
 anterolateral(watson jones),
 posterolateral (GIBSON)
 lateral Hardinge approach
 In order to increase the range of motion and decrease
friction and the risk of dislocation , the diameter of the
head was initially increased to 40(modular) and
eventually set to 28 mm conventional.

71.  Overall there were 3methods of stabilization of
implants in total hip replacement
 A) with the use of acrylic cement , a method with
results proved satisfactory
 B) with porous fixation with the use of
hydroxyappatite
 C) with pressfit fixation

72.  chromium cobalt alloys mixed with other minor metals had
assisted in better application of forces, stabilizing the area
and so they prevailed
 In cementless techniques, titanium is still preferred because
of its biocompatibility and rigidity.
 Another progress has been the use of hydroxyappatite ,
which by means of its absorption, increases the contact
forces between metal and bone

73.  Two parallel developments---
1. Ceramic insert between the surfaces decreases the friction
compared to metal on metal contact having a similar result
2. Secondly the surface replacement arthoplasty of the hip ,
which was the choice of treatment for young adults without
an indication of osteotomy
 Complications -acetabular loosening and bone loss
-fractures of the femoral neck were also
reported, in a lower frequency

74.  The total hip arthroplasty has been affectionately
named
 the operation of the century.
 This reflects the measure of success in which good,
predictable long-term results have been achieved. Its
current successes owe much to its modern orthopaedic
implant design,

76. The Knee
 As far as knee is concerned , an attempt to replace only the
affected compartment of the joint had started before the total
knee replacement surgeries during the 60s by MacInntosh and
MacKeever with the use of a metallic component unilaterally
or bilaterally on the articular surface of the tibia.
 The main disadvantage of this technique was the implant
loosening and its dip .
 In 1976 GOODFELLOW J & Connor presented an implamt
with harmonic and perpendicular articular surfaces between
which a polyethelenemovable meniscal shaped insert was
placed
 THE PROCEDURE WAS POSSIBLE WITH only a small
incision on the medial surface of the knee, thus the outcomes
were impressively better

77.  Fergusson 1860, started resection arthoplasty
 Verneuil performed the 1st interposition arthoplasty
 1940s- first artificial implants were tried when molds
were fitted into the femoral condyle
 1950s- combined femoral and tibial articular surface
replacement appeared as simple hinges

78.  Total knee replacement was presented during the 50s by
LESLIE SHIERS and BORJE WALDIUSS, who used a
metallic implant with rigid hinges which was stabilised not
only on articular surface but also in the medullary cavity of
the femur and tibia
 This implant offered correction regardless of the degree of
distortion or instability, satisfactory range of motion and
relief of pain
 The uniaxial movement of this implant on the multiaxial
motion of the human knee during gait was the reason for
its limited use

79.  Frank gunston (1971), developed a metal on plastic knee
replacement ,
 COVENTRY 1973 developed a geometric system with total
harmonic and perpendicular surfaces
 The ratio of implant loosening was exceptionally high due to
overshearing and rotation during the gait caused by the
uniaxial motion of the knee
 Initially, polyethelene was used for reduction of friction
 Loosening continued to be the main complication and the
number of revision surgeries was increased dramatically

80.  Freeman and Swanson , started using the condylar implant
ICLH with non-perpendicular articular surfaces during the 70’s
 This was totally or partially controlled in moving against the
plastic articular surface of the tibia
 John insall (1973) , designed the prototype for current TKR
prosthesis made of three components for the femur ,tibia and
patella
 Burstein modified the method in 1981 by means of a mechanism of
posterior cruciate ligament replacement, called the posterior
stabilised condylar knee
 Implants that preserve the posterior cruciate ligament were
characterised by the lack of harmony between the articular
surface of the femur and the tibia (CRUCIATE RETAINING)
 The discovery of the causes of failure guided to the attempt of
stabilization of the tibial implant to the cortical bone of the tibia
and the use of a stem that supports free movement of the plastic
tibial component on a metallic platform

81.  The new implants were created in which the cruciate ligaments
are sacrificed(TOTAL CONDYLAR PROSTHESIS) , the posterior
cruciate ligament is preserved(KINEMATIC, AGC) O
 Or the ability of choice is given to the patient (MILLER-
GALANTE, GENESIS )
 The use of thin polyethylene insert in implant with flat articular
surfaces(PCA of hungerford 1983)as well as flat shaped
polyethylene insert (KINEMATIC) was accompanied with an
extensive delamination of the plastic
 Towards the late 80s ,the use of implants with with
perpendicular, harmonic and extended surfaces of contact fixed
bearing began , CONSTRAINED TKR- , with the ability of
prosthesis to provide varus valgus and flexion –extension
stability in presence of ligament laxity or bone loss

82. TKR today
 Majority of TKR today are Condylar replacements
which consist of the following
1. Cobalt chrome alloy femoral component
2. Cobalt chrome alloy or titanium tibial tray
3. UHMWPE tibial bearing component
4. UHMWPE patella component

83. BIOMATERIALS
 Orthopaedic implants meant perform certain biological
functions by substituting or repairing different
 tissues such as bone
 cartilage ,ligaments and tendons,
 Three different generations
 (Hench & Polak 2002): Bioinert materials (first generation),
 Bioactive and biodegradable materials (second generation),
 Materials designed to stimulate specific cellular responses at the
molecular level (third generation).

84. First metallic biomaterials
 Stainless steel and cobalt–chrome-based alloys
 Ti and Ti alloys were introduced by the 1940s.
 NiTi shape memory alloys appeared by the 1960s
CERAMIC MATERIALS-
First-generation ceramic biomaterials, alumina, zirconia
 Replaced Metallic femoral heads of hip prostheses by high-
density and highly pure alumina
 Also used for acetabular cups,
 Showing excellent wear rates, Corrosion resistance, good
biocompatibility
 DISADVANTAGE-early failures due to their low fracture
toughness.

85. Polymers
 First generation
 silicone rubber, PE, acrylic resins, polyurethanes,
polypropylene (PP) and polymethylmethacrylate
(PMMA).
 Charnley (1960) introduced the self-polymerizing PMMA
bone cement into contemporary orthopaedics
 Powder phase consisting of prepolymerized PMMA with
 Initiator (to catalyse the polymerization process) and
 Radiopacifier (BaSO4 or ZrO2)
 A liquid phase formed by MMA monomer, an accelerator
reagent and a stabilizer

86. ROLE OF CEMENT
 Allows the secure fixation of implant to bone
 Transfers load evenly from implant to bone
 Maintains the bone stock
 Acts as shock absorber
 Can be used as a drug delivery system
 DISADVANTAGE
It does not promote a biological secondary fixation.

87. •They have been used in Vertebroplasty and Kyphoplasty).
•The same formulations as for cemented arthroplasties are still
used
•Several formulations with a higher concentration of
radiopacifier, [PE], and more specifically [UHMWPE] , is the
liner of acetabular cups in total hip arthroplasties
•Tibial insert and patellar component in TKR
• Spacer in intervertebral artificial disc replacement.
ADVANTAGE
• high abrasion resistance
•low friction & excellent toughness
•biocompatibility make it an ideal candidate

88. . SECOND GENERATION(1980 and 2000)
 The materials that interact with the biological
environment or the bioabsorbable materials which
underwent a progressive degradation while new
tissue regenerated and healed.
 Bioactive biomaterials led to the in vivo deposition
of a layer of HA(Hydroxy apatite) at the material
surface.
 In 1980s, several bioactive glasses (BGs), ceramics,
glass–ceramics and composites were used

89. Metals
 None of the metallic materials used in orthopaedics is
bioactive per se but two approaches can be
considered to obtain bioactive metals.
 Coating the surface of the implant
with a bioactive ceramic (HA and BGs).
 Chemically modify the surface of the material
to obtain the deposition of a bioactive ceramic in vivo
 Achieved by electrophoretic deposition
 plasma spraying
 radio frequency or ionic ray sputtering
 laser Ablation
majority are not cost-effective

90.  The most common ceramic materials can be classified
as BGs, glass–ceramics and calcium phosphates (CaPs)
both as ceramics and cements.
 Used as bone substitutes & bone defect fillers
 Good bioactive properties, enabling binding to the
bone with no mediation of a fibrous connective tissue
interface
 Bioactive ceramics have been reported to be
biocompatible and osteoconductive.

91. THIRD GENERATION
 They stimulate specific cellular responses at the
molecular level
 Temporary three-dimensional porous structures
that stimulate cells’ invasion, attachment and
proliferation,
 Also functionalized surfaces with peptide
sequences that mimic the ECM components which
trigger specific cell responses are developed
 Third generation coincide with tissue engineering
applications

92.  PLA(POLYLACTIC ACID),PGA(POLYGLYCOLIC ACID), PCL
(POLYCAPROLACTONE)and PHB(POLYHYDROXYBUTYRATE)
are the most widely used polymers
 PLA , COLLAGEN & Silk have been studied as for ligament
tissue engineering
 PCL and hyaluronic acid combination for meniscus tissue
engineering
 Hyaluronic acid, polyglactin , collagen, fibrin, alginates, and
glycosaminoglycans are under study for cartilage and
intervertebral disc applications
 Demineralized bone matrix (DBM) is currently being used
successfully in various clinical applications as an alternative to
autografts

93. STEEL
 Started IN SIBERIA, with discovery of a new MINERAL
chromite way back in 1776
 GULLIET was the first to make alloy systems called stainless
steel today,
 MONNARTZ rustlessness comes with atleast 13% chromium
 The 18-8 SMo was the 1st stainless steel to be used
 316 STAINLESS STEEL was described in 1959, but
 316L stainless steel was used due to low carbide content

94. Cobalt chromium alloys
 The cobalt-chromium-tungsten-nickel alloys(ASTM F-
90) is used for manufacture of fracture fixation
implants
 In clinical practice its used to make wire and internal
fixation devices including plates , intrameddulary rods
and screws

95. Titanium alloys
 Titanium is the 9th most abundant element in the
earth’s crust
 It is th only element that burns in nitrogen, the pure
form is very reactive
 It is used to make orthopaedic implants in two forms
1. Commercially pure
2. Variety of alloys
Titanium-aluminium-vanadium alloy (ASTM F-136) is
commonly refered to as Ti6AI4V. This alloy is most
frequently used to manufacture implants

96. Testing of implants
 Physical tests
1. Appearance : should be free of cracks , draw marks , pits,
& surface contamination
2. WEIGHT: Screws of identical diameter geometry and
length should weigh same,IF they are of same alloy
3. MAGNETISM: the 316 stainless steel is non magnetic
4. HARDNESS: ROCKWELL superficial hardness testing
to scale 30T
5. Spark test : for molybdenum

97. Chemical tests
 These are studied under the following headings
 Molybdenum detection test- by MINI MOLY DETECTOR KIT,
Available in regional ISI centres
 Molybdenum percentage estimation test- done in metal
testing laboratories in all major cities
 Corossion test-by AQUA REGIA
if the implants are identical alloys they should dissolve identically, the
percentage loss is esmitated and compared with standard one
(Isi316 steel should contain molybdenum between 2 and 3.5%)

98. Biological compatibility
 Magnetic steel implant corrode by GALVANIC reaction in
the body and hence should be rejected
 The carbon component increases the strength but the alloy
is undesireable
 Type 316L has a very low permissible level of carbon to
minimize this problem
 Though it is strong stiff and biocompatible material, 316L
HAS a slow but finite corrosion rate, concerns therefore
prevail about the long term effect of nickel ion
 Thus, stainless steel is best suited for short term
implantation in body