The document discusses osteoarthritis of the knee, including the anatomy and biomechanics of the knee joint, risk factors and clinical features of osteoarthritis, conservative and surgical management options. Specifically, it focuses on unicondylar knee arthroplasty versus high tibial osteotomy for the treatment of unicondylar osteoarthritis of the knee, outlining the indications, types of implants, and contraindications for unicondylar knee arthroplasty.

1. Presenter :-Dr abhishek chuadhary
Moderator:-Dr pavan kumar chebbi

2.  Applied anatomy of knee complex
 Biomechanics of knee joint
 OA knee
 Unicondylar OA
 Surgical management options for unicondylar
OA
 Comparisons results and study conclusions of
hto vs ukr for unicondylar OA

11.  The normal anatomical load-bearing axis of
the knee is viewed as ranging from 5 to 7
degrees of valgus and approximately 60% of
the weight-bearing force is thought to
transmit through the medial compartment
and 40% through the lateral compartment

17. (Degenerative
arthritis/osteoarthrosis/hypertrophic
arthritis)

18.  OSTEOARTHRITIS IS A NON-INFLAMMATORY,
DEGENERATIVE CONDITION OF JOINTS
CHARACTERIZED BY DEGENERATION OF
ARTICULAR CARTILAGE AND FORMATION OF
NEW BONE I.E. OSTEOPHYTES.

21.  COMMON IN WEIGHT-BEARING JOINTS SUCH
AS HIP AND KNEE.
 ALSO SEEN IN SPINE AND HANDS.
 BOTH MALE AND FEMALES ARE AFFECTED.
 BUT MORE COMMON IN OLDER WOMEN I.E.
ABOVE 50 YRS,PARTICULARLY IN
POSTMENOPAUSAL AGE.

22. RISK FACTORS
 OBESITY ESP OA KNEE
 ABNORMAL MECHANICAL LOADING
EG.MENISCECTOMY, INSTABILITY
INHERITED TYPE II COLLAGEN DEFECTS IN
PREMATURE POLYARTICULAR OA
INHERITANCE IN NODAL OA
 OCCUPATION EG FARMERS
INFECTION:NON-GONOCOCCAL SEPTIC ARTHRITIS
HEREDITARY
POOR POSTURE
AGEING PROCESS IN JOINT CARTILAGE
DEFECTIVE LUBRICATING MECHANISM
INCOMPLETELY TREATED CONGENITAL
DISLOCATION OF HIP

24. OA
Primary OA Secondary OA

25.  MORE COMMON THAN SECONDARY OA
 CAUSE –UNKNOWN
 COMMON-IN ELDERS WHERE THERE IS NO
PREVIOUS PATHOLOGY.
 ITS MAINLY DUE TO WEAR AND TEAR
CHANGES OCCURING IN OLD AGES MAINLY IN
WEIGHT BEARING JOINTS.

26.  DUE TO A PREDISPOSING CAUSE SUCH AS:
1.INJURY TO THE JOINT
2.PREVIOUS INFECTION
3.RA
4.CDH
5.DEFORMITY
6.OBESITY
7.HYPERTHYRIODISM

27.  OA IS A DEGENERATIVE CONDITION
PRIMARILY AFFECTING THE ARTICULAR
CARTILAGE.
1.ARTICULAR CARTILAGE
2.BONE
3.SYNOVIAL MEMBRANE
4.CAPSULE
5.LIGAMENT
6.MUSCLE

28.  Cartilage Is The 1st Structure To Be Affected.
 Erosion Occurs,often Central & Frequently In Wt.
Bearing Areas.
 Fibrillation,which Causes Softening,splitting And
Fragmentation Of The Cartilage,occur In Both Wt.
Bearing & Non-wt. Bearing Areas.
 Collagen Fibres Split And There Is Disorganisation
Of The Proteoglycon Collagen Relationship Such As
H2o Is Attracted Into Cartilage, Which Causes Futher
Softening And Flaking.These Flakes Of Cartilage
Break Off And May Be Impacted B/W The Jt.Surfaces
Causing Locking And Inflammation.

29. RIGHT: EARLY OA
WITH AREA OF
CARTILAGE LOSS IN
THE CENTER.
LEFT: MORE
ADVANCED CHANGES
WITH EXTENSIVE
CARTILAGE LOSS AND
EXPOSED
UNDERLYING BONE

30. Arthroscopic
appearances in OA of
the knee joint: fibrillated
surface of the cartilage
on the medial femoral
condyle

31.  Bone Surface Become Hard & Polished As
There Is Loss Of Protection From The
Cartilage.
 Cystic Cavities Form In The Subchondral Bone
Because Eburnated Bone Is Brittle And
Microfractures Occur.
 Venous Congestion In The Subchondral Bone.

32. Gross superior view
of a femoral head
from a patient with
radiographic stage i
oa. This shows an
area of complete
cartilage loss, with
polishing or
eburnation of the
underlying bone.

33.  Osteophytes form at the margin of the
articular surface,which may get projected into
the jt. Or into capsule & ligament,bone of the
wt.-Bearing jt.
 There is alteration in the shape of the femoral
head which becomes flat and mushroom
shaped.
 Tibial condyles become flatened.

35.  Synovial membrane undergo hypertrophy
and become oedematous (which can lead to
‘cold’ effusions).
 Reduction of synovial fluid secretion results
in loss of nutrition and lubricating action of
articular cartilage.
CAPSULE
It undergoes fibrous degeneration and there
are low-grade chronic inflammatory
changes

37.  Undergoes fibrous degernation
 There is low grade chronic inflammatory changes
and acc.To the aspect joint become contracted or
elongated.
Muscles
Undergoes atrophy,as pt. Is not able to use the jt.
Because of pain which further limits movts. And
function.

39.  Pain
 Stiffness
 Muscle spasm
 Restricted movement
 Deformity
 Muscle weakness or wasting
 Joint enlargement and instability
 Crepitus, Joint effusion

40.  PAIN AND TENDERNESS
◦ Usually slow onset of discomfort, with gradual
and intermittent increase
◦ Pain is more on wt. Bearing due to stress on the
synovial membrane & later on due to bone
surface,which r rich in nerve endings coming in
contact.
-Initially relieved by rest but later on disturb
sleep.
-Diffuse/ sharp and stabbing local pain

42.  PAIN AND TENDERNESS (CONT)
◦ Types of pain
 Mechanical: increases with use of the
joint
 Inflammatory phases
 Rest pain later on in 50%
 Night pain in 30% later on

43.  MOVEMENT ABNORMALITIES
◦ ‘Gelling’: stiffness after periods of inactivity,
passes over within minutes (approx 15min.) Of
using joint again
◦ Coarse crepitus: palpate/hear (due to flaked
cartilage & eburnated bone ends)
◦ Reduced rom: capsular thickening and bony
changes in joint,ms. Spasm or soft tissue
contracture.

44.  DEFORMITIES
◦ Soft tissue swelling:
 Mild synovitis
 Small effusions
◦ Osteophytes
◦ Joint laxity
◦ Asymmetrical joint destruction leading to
angulation

45. OSTEOARTHRITIS OF
THE DIP JOINTS. THIS
PATIENT HAS THE
TYPICAL CLINICAL
FINDINGS OF
ADVANCED OA OF THE
DIP JOINTS, INCLUDING
LARGE FIRM SWELLINGS
(HEBERDEN’S NODES),
SOME OF WHICH ARE
TENDER AND RED DUE
TO ASSOCIATED
INFLAMMATION OF THE
PERIARTICULAR TISSUES
AS WELL AS THE JOINT.

46. Knee joint effusion

47. A patient with
typical OA of the
knees. In the
normal standing
posture there is a
mild varus
angulation of the
knee joints due to
symmetrical OA of
the medial
tibiofemoral
compartments.

48. Pseudolaxity due
to cartilage loss.
The joint is not
loaded in the first
photograph

49. Unstable distal
interphalangeal
joints in OA. The
examiner is able to
push the joint from
side to side due to
gross instability, a
common finding in
late interphalangeal
joint OA.

53.  BLOOD TESTS: NORMAL
 RADIOLOGICAL FEATURES:
◦ CARTILAGE LOSS
◦ SUBCHONDRAL SCLEROSIS
◦ CYSTS
◦ OSTEOPHYTES

57.  EDUCATION
 PHYSIOTHERAPY
◦ EXERCISE PROGRAM
◦ PAIN RELIEF MODALITIES
 AIDS AND APPLIANCES
 MEDICAL TREATMENT
 SURGICAL TREATMENT

58.  NONSYSTEMIC NATURE OF DISEASE
 PREVENT OVERLOADING OF JOINT. OBESITY!!
 APPROPRIATE USE OF TREATMENT
MODALITIES
◦ IMPORTANCE OF EXERCISE PROGRAM
◦ AIDS, APLIANCES, BRACES
◦ MEDIAL TREATMENTS
◦ SURGICAL TREATMENTS

60.  WILL NOT ‘WEAR THE JOINT OUT’
 IMPORTANT FOR CARTILAGE NUTRITION
 SOME EVIDENCE THAT LACK OF EXERCISE
LEADS TO PROGRESSION OF OA

61.  ENCOURAGE FULL RANGE LOW IMPACT
MOVEMENTS EG SWIMMING, CYCLING
 AVOID
◦ PROLONGED LOADING
◦ ACTIVITIES THAT CAUSE PAIN
◦ CONTACT SPORTS
◦ HIGH IMPACT SPORTS EG RUNNING

62. Quadriceps exercises
for knee oa. Quadriceps
exercises are of proven
value for pain relief and
improving function, and
everyone with knee oa
should be taught the
correct techniques and
encouraged to make
these exercises a
lifetime habit. There is a
weight on the ankle.

63. Use of transcutaneous
nerve stimulation
(tens) as an adjunct to
other therapy for pain
relief at the knee joint.
The use of
acupuncture, tens and
other local techniques
to aid pain relief in
difficult cases of oa is
often worthwhile.

64.  BRACES / SPLINTS
 SPECIAL SHOES/INSOLES
 MOBILITY AIDS
 AIDS: DRESSING, REACHING, TAP OPENERS,
KITCHEN AIDS
 TAPING OF PATELLA IN PATELLO FEMORAL OA

65. Use of a cane, stick or other walking aid.
This patient, who has hip oa, has found
that she can reduce the pain in her
damaged left hip by leaning on the stick
in the right hand as she walks. The
reduction in loading can be huge, and the
effect on symptoms and confidence with
walking very beneficial.

66. The use of shoes and
insoles to reduce impact
loading on lower limb
joints. Modern sports
shoes (‘trainers’) often
have appropriate
insoles. Alternatively,
special heel or shoe
insoles of sorbithane or
viscoelastic materials
can be used. They may
help relieve pain as well
as reducing the peak
impact load on the
joints during walking.

67.  SIMPLE ANALGESICS: PARACETAMOL, LOW
DOSE IBUPROFEN
 NSAID’S/COXIBS PRN REGULAR
 INTRA-ARTICULAR CORTICOSTEROIDS
 TOPICAL TREATMENT EG NSAID CREAMS,
CAPSAICIN
 ‘CHONDROPROTECTIVE AGENTS’

68. A patient with oa of
the carpometacarpal
joint of the left thumb
undergoing
arthrocentesis for
injection of a depot
corticosteroid
preparation. The doctor
is distracting the
patient’s thumb to
open up the joint
space.

70.  Indications: pain affecting work, sleep,
walking and leisure activities
 Complications
◦ sepsis
◦ loosening
◦ lifespan of materials (mechanical failure)

74.  Surgical option for knee arthritis when only one compartment of
the knee is involved.
 Epidemiology
◦ 5% of surgeries where knee arthroplasty is indicated
are unicompartmental knee replacements
◦ location
 fimedial compartment is most common
 Types of implants
◦ fixed-bearing
 historical standard of care
◦ mobile-bearing
 pros
 weightbearing through the meniscus increases conformity and contact
without increasing constraint
 decrease in wear pattern
 excellent survivorship out to the second decade
 cons
 technically demanding
 bearings can dislocate

76.  INDICATIONS
 controversial and vary widely as an alternative to
total knee arthroplasty or osteotomy for
unicompartmental disease.
 classicaly reserved for older (>60), lower-
demand, and thin (<82 kg) patients
◦ 6% of patient's meet the above criteria with no
contraindications
 new effort to expand indications to include
younger patients and patients with more
moderate arthrosis.

77.  Contraindications
◦ inflammatory arthritis
◦ ACL deficiency
 absolute contraindication for mobile-bearing UKA and lateral
UKA
 controversial for medial fixed-bearing
◦ fixed varus deformity > 10 degrees
◦ fixed valgus deformity >5 degrees
◦ restricted motion
 arc of motion < 90°
 flexion contracture of > 5-10°
◦ previous meniscectomy in other compartment
◦ tricompartmental arthritis (diffuse or global pain)
◦ younger high activity patients and heavy laborers
◦ overweight patients (> 82 kg)
◦ grade IV patellofemoral chondrosis (anterior knee pain)

78.  Fixed-bearing
◦ 1st decade results
 10-year survivorship from studies done in 1980s and 1990s
ranges from 87.4% to 96%
 the standard faliure rate in the first decade is 1%
◦ 2nd decade results
 rapid decline in survivorship ranging from 79% to 90%
 Mobile-bearing
◦ excellent clinical results with 15-year survivorship
reported at 93%.
 Long-term results
◦ lateral compartment arthroplasties have equivalent results
to medial
◦ revision rates are worse than total knee revision rates

79.  Marmor (1973) introduced the first UKA in 1973 and
it subsequently became an attractive concept and an
alternative procedure to HTO.
 The Oxfordmobile meniscal bearing system
 (Oxford UKA), designed by Goodfellow and O’Connor
(1986), addressed these problems by allowing more
conformity between the femoral component and the
 tibial insert in order to reduce the surface forces.
This then allowed the
 polyethylene to move on the underlying tibial tray,
thereby avoiding the problems of increased
constraint

80.  Complications
 Stress fractures
◦ always involve tibia
◦ associated with high activity and patient weight
◦ clinically there will be a pain free interval followed by
spontaneous pain with activity
◦ blood commonly found on joint aspiration
 Tibial component collapse
◦ poor mechanical properties of bone

81.  Advantages compared to TKA
◦ faster rehabilitation and quicker recovery
◦ less blood loss
◦ less morbidity
◦ less expensive
◦ preservation of normal kinematics
 theory is that retaining ACL, PCL and other compartments leads to
more normal knee kinematics
◦ smaller incision
 less post-operative pain leading to shorter hospital stays
 compared to osteotomy
◦ faster rehabilitation and quicker recovery
◦ improved cosmesis
◦ higher initial success rate
◦ fewer short-term complications
◦ lasts longer
◦ easier to convert to a TKA

82.  High tibial osteotomy is a well established
procedure for the treatment of unicompartmental
osteoarthritis of the knee. Most reports have
shown approximately 80% satisfactory results at
5 years and 60% at 10 years after high tibial
osteotomy.
 The biomechanical rationale for proximal tibial
osteotomy in patients with unicompartmental
osteo-arthritis of the knee is “unloading” of the
involved joint compartment by correcting the
malalignment and redistributing the stresses on
the knee joint.

83.  (1) pain and disability resulting from
osteoarthritis that significantly interfere with
highdemand employment or recreation and
 (2) evidence on weightbearing radiographs of
degenerative arthritis that is confined to one
compartment with a corresponding varus or
valgus deformity. The patient must be able to
use crutches or a walker and have sufficient
muscle strength and motivation to carry out a
rehabilitation program

84. (1) narrowing of lateral compartment cartilage
space,
(2) lateral tibial subluxation of more than 1 cm,
(3) medial compartment tibial bone loss of more
than 2 or 3 mm,
(4) flexion contracture of more than 15 degrees,
(5) knee flexion of less than 90 degrees,
(6) more than 20 degrees of correction needed,
(7) inflammatory arthritis, and
(8) significant peripheral vascular disease.

85. Four basic types are most commonly used
 medial opening wedge,
 Wedge bone graft and rigid fixation required.
 lateral closing wedge,
 Longest track record .pop cast immobiization
 dome, aka ‘barrel vault’
 Considered more stable ,accurate and better
adjustability of deformity correction.special jigs
needed.
 medial opening hemicallotasis.
 uses an external fixator to distract the osteotomy site
gradually.

86. (1) age younger than 60 years,
(2) purely unicompartmental
disease,
(3) ligamentous stability, and
(4) preoperative arc of motion of at least 90 degrees.
Normally, there is valgus alignment of 5 to 8 degrees in
the tibiofemoral angle as measured on radiographs taken in
the weight-bearing position. The amount of correction of the
arthritic knee needed to achieve a normal angle is calculated,
and an additional 3 to 5 degrees of overcorrection is added
to achieve approximately 10 degrees of valgus. With a varus
deformity, the only limitation in the amount of correction
from a valgus osteotomy is the size of the bone wedge that
can be taken proximal to the patellar tendon.

88.  The advantage
 (1) it is made near the deformity, that is, the knee
joint;
 (2) it is made through cancellous bone, which heals
rapidly;
 (3) it permits the fragments to be held firmly in
position by staples or a rigid fixation device, such as
a plate-and-screw construct; and
 (4) it permits exploration of the knee through the
same incision. After this operation, the danger of
delayed union or nonunion is slight and prolonged
immobilization in a cast is unnecessary, especially
with rigid internal fixation.

92.  Tricortical iliac crest autograft with supplemental
cancellous graft material also is recommended;
however, other structural graft material, such as
hydroxyapatite wedges, can be successful.
Opening wedge osteotomy .
 should be done if the involved extremity is 2 cm
or more shorter than the contralateral extremity.
 Opening wedge osteotomy also may be indicated
in patients with laxity of the medial collateral
ligament or combined anterior cruciate ligament
deficiency.

94.  roughly 1 degree of correction for each 1 mm of length at
the base of the wedge (e.g., 20 degrees of correction =a
20-mm base of the wedge). This is true only if the tibia is
57 mm wide, however, and we prefer using exact
measurements for the width of the base of the osteotomy,
with a right triangle con-structed from a preoperative
drawing or the
 formula W =diameter ×0.02 ×angle or tangent tables.
 Alternately, full-length, near actual size, standing
anteroposterior radiographs can be used to determine the
size of the wedge needed. The desired alignment, based on
the mechanical axis from the center of the femoral head
through the knee to the center of the ankle, can be
achieved by cutting the appropriate-sized wedge from the
proximal tibia.

96.  recurrence of deformity (loss of correction) most
commen,
 peroneal nerve palsy,
 nonunion,
 infection,
 knee stiffness or instability,
 intraarticular fracture,
 deep vein thrombosis,
 compartment syndrome, patella infra, and
osteonecrosis of the proximal fragment.
 Inadequate correction and recurrent varus
deformity have been reported to occur in 5% to
30% of patients with proximal tibial osteotomy.

99. ABSTRACT
 BACKGROUND:the choice of surgical treatments
for unicompartmental osteoarthritis (oa) of the
knee is still somewhat controversial. midterm
results from cases treated using
unicompartmental knee arthroplasty (uka) or open
wedge high tibial osteotomy (owhto) were
evaluated retrospectively.
 METHODS:twenty-seven knees of 24 patients with
varus deformities underwent owhto and 30 knees
of 18 patients underwent uka surgeries for the
treatment of medial compartmental osteoarthritis
(oa). the kss score,fta, range of motion and
complications were evaluated before and after
surgery.

100.  RESULTS:
the preoperative mean kss scores were 49 points in the
owhto group and 62 in the uka group which improved
postoperatively to 89 (excellent; 19 knees, good; 8 knees), and
88 (excellent; 25, good; 4, fair; 1), respectively. there was no
significant difference between the owhto and uka scores.
seventeen patients in the owhto group could sit comfortably in
the formal japanese style after surgery. the preoperative mean
fta values for the owhto and uka groups were 182 degrees and
184, and at follow-up measured 169 and 170, respectively. in
the uka group, the femoral component and the polyethylene
insertion in one patient was exchanged at 5 years post-
surgery and revision tkas were performed in 2 cases. in the
owhto group, one tibial plateau fracture and one subcutaneous
tissue infection were noted.

101. Treatment options should be carefully
considered for each OA patient in accordance
with their activity levels, grade of advanced
OA, age, and range of motion of the knee.
OWHTO shows an improved indication for
active patients with a good range of motion
of the knee.

102. The Iowa Orthopaedic Journal volume 30

103. This review examined the literature
regarding high tibial osteotomy (HTO) and
unicompartmental knee arthroplasty (UKA),
focusing on indications,survivorship and
functional outcomes of the two procedures, as
well as revision to total knee arthro-plasty
(TKA) after failed HTO or UKA.
The aim of this review is to identify the
correct in-dications for HTO and UKA, analyze
the results from both treatments, and report
on the comparison studies in the literature.

104. HTO and UKA share the same indications in
selected cases of medial unicompartmental
knee arthrosis. These indications include
patients who are:
1) 55 to 65 years old;
2) moderately active;
3) non-obese;
4) have mild varus malalignment;
5) no joint instability;
6) good range of motion; and
7) moderate unicompartmental arthrosis

105. Few studies are available in the literature
comparing the outcomes of HTO and UKA.
those few studies show slightly better results
for UKA in terms of survivorship and
functional outcome. Nevertheless, the
differences are not remarkable, the study
methods are not homogeneous and most of
the papers report on closing wedge HTOs.
For these reasons, no definitive conclusions
can be drawn.

106. TKA represents the revision option for both
treatments and yields satisfactory functional
outcomes and survivorship. Whether revision
HTO and UKA-to-TKA perform any worse than
primary TKA is still controversial. With the
correct indications, both treatments produce
durable and predictable outcomes in the
treatment of medial unicompartmental arthrosis
of the knee. there is no evidence of superior
results of one treatment over the other.

107.  High tibial osteotomy and unicompartmental
knee arthroplasty represent a “strange couple” in
the treat-ment of medial compartment arthrosis
of the knee.
 HTO has long been considered a successful and
widely performed procedure to address
malalignment and subsequent unicompartmental
arthrosis of the knee. UKA has gained popularity
in the management of uni-compartmental
arthrosis, when total knee arthroplasty and HTO
are the only alternative treatments available.

108. The original intent of HTO is correction of a
knee angular deformity or metaphyseal tibial
malalignment, which determines a medial
symptomatic overload or initial arthrosis.
The ideal candidate for an HTO is
1. a young (less than 60 years old),
2. active patient affected by symptomatic mild-to-
moderate varus knee (5 to 15 degrees) with mild
medial compartment involvement (less than grade III,
Ahlback classification), intact lateral and
patellofemoral compartments,
3. good knee range of motion (knee flexion >120
degrees), and
4. no joint laxity or instability.

109.  However, the indications for HTO have been
recently expanded to include posterolateral
laxity and varus hyperextension thrust,
anterior cruciate liga-ment (ACL) deficiency
and varus thrust or alignment, and combined
ligamentous laxity with varus or
posterolateral thrust.

110. UKA is the partial surface replacement of the knee
joint. Its increasing popularity is due to:
1) the possibility of replacing a severely damaged
compartment;
2) the preservation of bone stock; together with
3) a faster recovery time and minimal invasiveness
compared to TKA.
 With recent technical improvements, UKA is
consistently less invasive, and newer designs with
arthroscopic techniques will soon be introduced
into the marketplace.

111. 1) unicompartmental osteoarthritis or femoral
condyle avascular necrosis, with intact lateral and
patellofemoral compartments;
2) age over 60 years;
3) low demands;
4) no obesity;
5) minimal pain at rest;
6) range of motion (ROM) arc over 90 degrees with
less than 5 degrees flexion contracture; and
7) within 10 degrees of axial malalignment, which
can be passively corrected almost to neutral.
Anterior cruciate ligament (ACL) deficiency has been
considered a contraindication??

112. SUMMARY OF INDICATIONS OF HTO AND UKA OR BOTH

113.  Many papers in the literature described the
outcomes of HTO and UKA.
 These mainly focused on survivorship analyses,
technical features (such as closed versus open
HTO, or all polyethylene versus metal-backed
tibial UKA),
 complications and adverse effects of the
procedures, as well as
 outcomes of revisions to TKA.
 Only a few papers reported a direct comparison of
the two procedures

114.  Survivorship analyses- the 10-year sur
vivorship increased from around 50% to 80%
 Patient satisfaction and clinical results were
reported to be good as well, with 50 to 80%
achieving good to excellent results at five-to-
seven years follow-up, and 30 to 60% good to
excellent results at 10-to-15 years follow-
up.

115.  unfavorable factors.
1. Advanced age,
2. over- or under-correction,
3. instability and severe arthrosis
4. The goal to be achieved in alignment
assessment is a slight valgus overcorrection
(2 to 5 degrees)

116. Controversies still exist regarding three topics
and these include:
1) the most reliable HTO technique (closing,
opening, or dome),
2) the clinical implications of patellar height
changes, and
3) the technical difficulties related to surgical
technique/means of synthesis.

117.  The complications-
1. fibular osteotomy or proximal tibiofibular joint
disruption,
2. peroneal nerve dissection,
3. more demanding subsequent TKA,
4. loss of bone stock, and
5. more difficulty controlling tibial slope (with a
tendency to decrease it).
 For all these reasons, the opening wedge HTO gained
popularity and became a widely used alternative. This
technique however is not itself free from drawbacks
including the necessity for bone grafting and possible
collapse or loss of correction.

118.  UKA was introduced in the 1970s but did not
gain wide acceptance due to poor early
results, high failure rates, and high technical
demands .
 10 -15 years survival rate ranges from 82 to
95 %
 Aspects which most likely affect the outcome
of UKA are prosthetic design, alignment, and
stability and experience of surgeon.

120. JANUARY 2014

121.  High tibial osteotomies (HTO) and unicompartmental knee
arthroplasties (UKA) are performed for the treatment of
isolated unicompartmental osteoarthritis (OA) of the knee.
 Before the development ofknee arthroplasties, HTO was
the most common operative treatment option for knee OA.
 Over the past two decades, the incidence of osteotomies
has decreased, but symptomatic, radiologically mild or
moderate knee OA is still commonly regarded as an
indication of HTO in young and active patients
 After development and popularisation of total knee
arthroplasty (TKA), the overall proportion of UKAs has
decreased in the treatment of knee OA . However, UKA is
provided as an option for TKA in cases of isolated
unicompartmental knee OA, and significant numbers of
UKAs are still performed worldwide.

122.  HTO alters the anatomy and biomechanics of the knee. The
most common changes are ligamental imbalance, patellar
tendon length alteration, scar formation and possible
rotational deformities.
 All these factors may make a subsequent TKA procedure
more difficult, but most of the previous studies show no
adverse effects on the results of subsequent TKA.
 Results of UKA operations are controversial. Most single
centre studies report UKA results that are comparable with
those of TKA However, these studies are not supported by
available arthroplasty register data from Australia, Finland,
New Zealand, Norway, Sweden and the United Kingdom,
which report repeatedly inferior survivorship of UKA
compared with TKA patients.

132.  Marmor (1973) introduced the first UKA in 1973
and it subsequently became an attractive
concept and an alternative procedure to HTO.
 The Oxfordmobile meniscal bearing system
(Oxford UKA), designed by Goodfellow and
O’Connor (1986), addressed these problems by
allowing more conformity between the femoral
component and the tibial insert in order to
reduce the surface forces. This then allowed the
polyethylene to move on the underlying tibial
tray, thereby avoiding the problems of increased
constraint

138. following conclusion can be made based on the results of this study.
1. The overall incidence of osteotomies in the treatment of knee OA has
decreased steadily over the last two decades, but in the age group less than 50
years, the incidence has slightly increased. The decline in incidence has been
steeper in female patients.
2. The short term survivorship of HTO at a nationwide level is comparable with
that regularly reported in single hospital or surgeon series, but the midterm
survivorship is worse. Females and patients aged more than 50 years have
poorer results.
3. The survivorship of TKAs after previous HTO is satisfactory when compared
with that following routine primary TKAs.
4. The survivorship of UKA cases is poorer compared that of TKA. Critical
patient screening for indications and adequate surgical techniques are crucial
to provide satisfactory UKA results for selected patients with isolated knee
osteoarthritis. In addition, UKA patients have a high revision rate, especially
because of aseptic loosening.

139. JBJS 1986 RETROSPECTIVE STUDY
COMPARISON AFTER 5-10 YEARS

144.  This five to ten year study has shown
significantly better results in terms of pain
and function ,in similar group of patients for
unicompartmental degenerative disease of
the knee.
 However the age group (mean age 63 years)
for tibial osteotomy is not favorable as we
know now may have resulted in outright
better outcome for ukr.

146.  Isolated medial joint line pain, age 40 to 60
years, body mass index (BMI) < 30, high
demand activity but no running or jumping,
varus malalignment < 15 degrees,
metaphyseal varus of tibia> 5 degrees, full
range of movement, normal lateral and
patellofemoral compartments, no defect of
the posteromedial tibia, normal ligament
balance, nonsmoker and some level of pain
tolerance.

148.  Improvements in surgical techniques and
 instruments have given the UKA procedure potential advantages over TKA in
 properly selected patients. These includeless bone resection, preservation of the
 cruciate ligaments, quicker recovery, decreased perioperative complications and a
 subjective preference as feeling “more normal”, returning to sports, improved
 walking ability, and lower cost
 Only two prospective RCTs have compared UKA and TKA procedures. In the
 first, 15-year follow-up study, UKA produced similar or slightly better results
 compared with TKA. The survivorship of the implant in both groups, with
 revision or a Bristol Knee Score < 60 as the endpoint, was 89.8% in the UKA
 group and 78.7% in the TKA group. The Bristol Knee Scores of the UKA group
 was better throughout the study period and at 15 years 15 of the surviving UKAs
 (71.4%) and 10 of the surviving TKAs (52.6%) achieved an excellent outcome. In
 the second RCT study, including 56 knees(mean follow-up 52 months, range 70–
 100), mobile bearing UKA achieved similar clinical effects to those of TKA, but
 had a higher first year revision rate because of the learning curve. According to
 the scale of the Knee Society, at the latest follow-up, the mean Knee Society
 score was 80.6 (range 70–100) and 78.9 (range 70–87) for UKA and TKA,
 respectively. Seven UKAs were converted to TKA due to component loosing – all
 of them within the first two years of starting the procedure and all of them in
 relatively young patients. None of the TKAs was revised (Sun & Jia 2012).