This document discusses osteotomy and unicompartmental knee replacement (UKR or "Uni Knee") for the treatment of varus malalignment and osteoarthritis in the knee. It provides details on the surgical techniques, outcomes, advantages, and contraindications of high tibial osteotomy (HTO) and UKR. Non-operative treatments for knee osteoarthritis like weight loss, exercise, and injections are also summarized.
High tibial osteotomy (HTO) is a common and widely accepted procedure in orthopaedic surgery. In the literature, we find descriptions of the technique dating back to the 50s, with Jackson (Jackson, 1958). However, it was not until the 70s, with the publications of Conventry (Coventry, 1969 and 1973) and Insall (Insall, 1975), that proximal tibial osteotomy became common practice as a treatment option for medial compartment osteoarthritis of the knee usually associated to varus deformity. At that time, closing wedge osteotomies were performed, despite the greater technical difficulty and risks involved, as there were no fixation materials available that could enable opening wedge osteotomy. Only after the development of medial wedge plate fixation that opening wedge osteotomy became applicable (Puddu, 2004).
The goals of HTO are:
1. To reduce knee pain by transferring weight-bearing loads to the relatively unaffected compartment;
2. To increase the life span of the knee joint, by slowing or stopping the destruction of the medial joint compartment. This could delay the need of a joint replacement.
High tibial osteotomy (HTO) is a common and widely accepted procedure in orthopaedic surgery. In the literature, we find descriptions of the technique dating back to the 50s, with Jackson (Jackson, 1958). However, it was not until the 70s, with the publications of Conventry (Coventry, 1969 and 1973) and Insall (Insall, 1975), that proximal tibial osteotomy became common practice as a treatment option for medial compartment osteoarthritis of the knee usually associated to varus deformity. At that time, closing wedge osteotomies were performed, despite the greater technical difficulty and risks involved, as there were no fixation materials available that could enable opening wedge osteotomy. Only after the development of medial wedge plate fixation that opening wedge osteotomy became applicable (Puddu, 2004).
The goals of HTO are:
1. To reduce knee pain by transferring weight-bearing loads to the relatively unaffected compartment;
2. To increase the life span of the knee joint, by slowing or stopping the destruction of the medial joint compartment. This could delay the need of a joint replacement.
Total Shoulder Arthroplasty | Reverse Shoulder Replacement | South Windsor, R...James Mazzara
https://hartfordsportsorthopedics.com/
In this presentation, Dr. Mazzara discusses the pathology, surgical techniques, and potential complications during a total shoulder replacement and a reverse total shoulder replacement.
To learn more about shoulder replacements, please visit: https://hartfordsportsorthopedics.com/total-shoulder-replacement-arthroplasty-south-windsor-rocky-hill-glastonbury-ct/
Safe surgical dislocation for femoral head fractures.dr mohamed ashraf,dr rah...drashraf369
femoral head fractures are very complex fractures that need immediate and prompt surgical intervention.conventional surgical appproaches to hip may lead to short and long term complications.dr mohamed ashraf ,dr rahul thampi et al are presenting their experience with gantz safe surgical dislocation approach to surgical management of femoral head fractures
Update on ACL reconstruction, with information on current direction of demineralized bone matrix (DBM) use in bone tunnels and biocartilage on chondral lesions
Total Shoulder Arthroplasty | Reverse Shoulder Replacement | South Windsor, R...James Mazzara
https://hartfordsportsorthopedics.com/
In this presentation, Dr. Mazzara discusses the pathology, surgical techniques, and potential complications during a total shoulder replacement and a reverse total shoulder replacement.
To learn more about shoulder replacements, please visit: https://hartfordsportsorthopedics.com/total-shoulder-replacement-arthroplasty-south-windsor-rocky-hill-glastonbury-ct/
Safe surgical dislocation for femoral head fractures.dr mohamed ashraf,dr rah...drashraf369
femoral head fractures are very complex fractures that need immediate and prompt surgical intervention.conventional surgical appproaches to hip may lead to short and long term complications.dr mohamed ashraf ,dr rahul thampi et al are presenting their experience with gantz safe surgical dislocation approach to surgical management of femoral head fractures
Update on ACL reconstruction, with information on current direction of demineralized bone matrix (DBM) use in bone tunnels and biocartilage on chondral lesions
Posterolateral corner injuries of knee joint Samir Dwidmuthe
Missed posterolateral corner injuries of knee joint is a common cause for failure of ACL and PCL reconstruction only next to malpositioned tunnels.
Isolated PLC injuries are uncommon, making up <2% of all acute knee ligamentous injuries. Covey JBJS 2001
Incidence of PLC injuries associated with concomitant ACL and PCL disruptions are much more common (43% to 80%). Ranawat JAAOS 2008
A recent (MRI) analysis of surgical tibialplateau fractures demonstrated an incidence of PLC injuries in 68% of cases. Gardner JOT 2005
Take home message
PLC injuries to be ruled out in every case of ACL& PCL rupture.
Neurovascular integrity to be checked in every case.
Grade I & II can be managed conservatively.
Grade III Acute- Repair.
Grade III Chronic- Anatomic PLC recon.
Beware of varus knee alignment.
Patella dislocation is a common problem in the young. Recurrence of dislocation can be significant problem causing pain and discomfort. The assessment and guidelines towards non-surgical and surgical treatment options are discussed here.
The effect of intact fibula on functional outcome of reamed intramedullary in...Love2jaipal
detailed journal club presentation on The effect of intact fibula on functional outcome of reamed intramedullary interlocking nail in open and closed isolated tibial shaft fractures
Total knee replacement is a salvage procedure in orthopaedic surgery to provide a painless, mobile and stable knee joint to improve quality of life of patients suffering from afvanced painful arthritis commonly osteoarthritis, rheumatoid arthritis and rarely post-traumatic arthritis. Damaged cartilages and bones are carefully removed by measured resection and the collateral ligaments are preserved and balanced for creating a equal gap both in knee flexion as well as in knee extension for restoring anatomy. the main indication for doing total knee replacement is pain relief. The overall functional outcomes in terms of functional results are good after total knee replacement. Wound infection must be prevented by strict aseptic precautions during surgery.
We have a moral responsibility to care for the wellbeing of our staff
Incivility cannot be tackled by increasing awareness and education alone
Governing bodies, surgeons and healthcare managers must play a bigger role in setting the tone for professionalism
The BOA needs to build systems that serve as a check against some of our human impulses
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
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Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
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Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
5. OA Nonoperative treatment
Strategies may include
Weight loss
Exercise
Patient education
Analgesia, (NSAIDs)
Bracing
Intra-articular (IA) injections. Cochrane reviews
Steroids (better than placebo but not longer than 4wks
HA more prolonged effect than steroids
6. Weight loss causes a significant risk reduction of knee
OA in the general population
The reduction was greater in severe symptomatic OA than in asymptomatic radiographic
OA
Meta-analysis of 47 studies involving 446000 pts
7. m,Muscle strengthening and aerobic exercises are effective in
reducing pain and improving physical function in mild to
moderate OA of the knee
8. A total of 180 patients with osteoarthritis of the knee were
randomly assigned to receive arthroscopic débridement,
arthroscopic lavage, or placebo surgery
Population was older male veterans
The prevalence of mechanical symptoms was not provided
Malalignment was not reported
10. Osteotomy
around the knee
Aims of valgus osteotomy
Unload the medial compartment by slightly
overcorrecting into valgus
Unloading any ligament reconstruction in patients
with a varus thrust
To change the tibial slope in order to reduce
translational forces and improve AP instability
11.
12. HTO for varus Malalignment
PostGrad Orth Deiary Kader
13. Lateral closed-wedge high tibial osteotomies have
been the treatment of choice since 1965
(Coventry, 1965).
PostGrad Orth Deiary Kader
14. OPEN Wedge HTO 1987
The open-wedge high tibial osteotomy
gained recognition after the encouraging
reports of (Hernigou et al., 1987).
Wedges of bone that were obtained from
the iliac crest were inserted into the
defect
17. Proximal or High Tibial Osteotomy (HTO)
The IDEAL candidate for HTO
Age <60 years
Isolated medial OA
Good ROM
Less than 5° FFD knee
>120° flexion knee
Patients should be
able to use crutches
Have no major varicose veins or peripheral vascular disease
18. The International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine
PostGradOrthDeiaryKader
21. Distal Femur Osteotomy
Valgus deformity of 12º or more needs distal femoral
varus producing osteotomy to address a lateral femoral
condyle deficiency and to prevent joint line obliquity and
gradual lateral tibial subluxation.
≈
22. Planning
Standing, long leg radiographs in neutral rotation
Measure the mechanical axis (normal = 1.2o varus)
Anatomical axis (60-70 valgus)
Measure the degree of deformity
& plan the size of wedge necessary
23. Planning
62.5% across tibial plateau from medial side
Final alignment should create 10º–13 valgus.
Overcorrection of 3º–5º above the 6º–7º normal valgus
angle
Medial tibial cortex represents the apex of the
bony wedge and should be left intact
29. Closed wedge HTO
Surgical technique
Arthroscopy
Computer-aided measurement of the wedge size or
A 10-mm wedge excision leads to
10º corrections in 57-mm-wide tibia
An angular jig is more accurate
30. Closed wedge HTO
Surgical technique
Curved incision from the head of the fibula to 2 cm below the tibial
tubercle. Peroneal nerve protected
Excise the bare area of the fibula head Or proximal tibiofibula joint
separated using a cob elevator
A calibrated osteotomy guide must be used for the bone cut
Leave 15–20 mm of tibial plateau to avoid fracture
Fix with a plate or staples
Rigid fixation+ early mobilisation eliminates patella ligament contracture
DVT prophylaxis similar to post TKR
33. Fibular osteotomy, Separating tibiofibular joint
Contracture of the patellar tendon, patellar baja
leg shortening
High Tibial Osteotomy with a Calibrated Osteotomy Guide, Rigid Internal Fixation, and Early Motion. Long-Term Follow-up*
ANNETTE BILLINGS, M.D.†; DAVID F. SCOTT, M.D.‡; MARCELO P. CAMARGO, M.D.§; AARON A. HOFMANN, M.D.§, SALT LAKE CITY, UTAHJ
Bone Joint Surg Am, 2000 Jan
Closed wedge HTO
Disadvantages
34. OPEN W HTO
Surgical Techineque
The MCL mobilize.
Two 2.5-mm Kirschner wires mark the oblique osteotomy
Starting proximal to the pes anserinus
4-5 cm distal to the joint line
The wires to the tip of the fibula 10-15mm
The osteotomy of the posterior two-thirds of the tibia
Leave a 10-mm lateral bone bridge intact.
Hinge on the lateral - not posterolateral - side of the tibia
The second osteotomy begins in the anterior one-third of the
tibia at an angle of 135° while leaving the tibial tuberosity intac
41. Lateral Open Wedge Distal Femur
single cut
easier approach to femur
easily adjustable correction
supratrochlear area disrupted
weak medial hinge point
plate location complaints
very unstable if hinge point fractures
slowest bone healing
role of grafts unclear
42. Methods of osteotomy Fixation
Cast immobilisation
Staples
Plate and screw
External fixator
Distraction osteogenesis. Correction can be
adjusted after surgery. But pin tracts create a
potential problem for subsequent TKA
43. Complications
Inadequate valgus correction
Overcorrection – PFJ derangement
Alteration in patella height
Intra-articular fracture
Osteonecrosis of the tibial plateau
45. Open wedge HTO
Advantages
Easier to achieve precise angular correction
Preserves bone stock (subsequent TKR is technically easier)
Makes tightening of the MCL easier
Preserve the lateral side for LCL or posterolateral
reconstruction if insufficient
No risk to peroneal nerve
Less dissection
46. Requires a bone graft (substitute, autograft,
allograft)
Increased incidence of non-union and delayed
union
Large correction may affect leg lengthening
Loss of fixation and recurrence of varus deformity
Worsens patella Baja
Open wedge HTO
Disadvantages
47. OW-HTO
Delayed union/nonunion rates were 2.6%, 4.6%, and
4.5% for autograft, allograft bone, and synthetic bone
substitutes, respectively
Non-locking plates (n = 2,148) had a rate of delayed
union/nonunion of 3.7% and a mean loss of correction
over time of 0.5°
Locking plates (n = 681) had a rate of delayed
union/nonunion of 2.6% and a loss of correction of
48. Coventry report
Outcome
5-year survival of 87%
10-year survival of 66%
However the 5-year survival was reduced down to
38% when valgus angulations at 1 year was less
than 8º in a patient whose weight was more than
1.32 times the ideal weight.
49. Outcome
Obesity and inadequate correction were
negative prognostic factors.
Age < 50 years to be a positive prognostic
factor
Joint line preservation is key to success.
50. OW-HTO vs CW-HTO
RCT 92 pts and 6 years FU
More Complications in open WHTO & more conversion to TKR in closed WHTO
SEPT 2014
51. Valgus high tibial osteotomy reduces pain and
improves knee function in patients with medial
compartmental osteoarthritis of the knee.
52. Principles
Uni Knee
Appropriate for 25% of osteoarthritic knees needing
replacement
Never release the MCL
Polyethylene dislocation rate is 1/200 after medial
compartment UKR (Oxford)
Polyethylene dislocation rate is 10% after lateral
compartment UKR
Dislocation rate can be reduced by using a fixed
bearing UKR.
53. ?
What are the Absolute contraindications
for Unicompartmental knee replacement?
What are the Advantages and
disadvantages?
54. Uni Knee Advantages
• Retains knee kinematics
• Restores function and range of movement
• Rapid recovery: 3X faster than TKR
• Less blood loss
• Cost less than TKR (all factors considered)
• Quicker operation than TKR
• Quicker return to work than after TKR
• High flexion lifestyle.
55. Uni Knee
Advantages
• Lower infection rate (halved) compared with TKR
• Allows minimally invasive approach
• Easier to revise than HTO?
• No patellar fractures or dislocations
• Maximises the longevity of total knee arthroplasty
• Reduced incidence of DVT
• Reduced mortality from pulmonary embolism
56. Prerequisites
Intact ligaments (especially ACL and PCL)
Correctable varus deformity
Less than 10° FFD
Flexion beyond 100°
Clinically asymptomatic PFJ and contralateral
compartment.
58. Relative contraindications
ACL degeneration
Chondrocalcinosis
Lateral meniscectomy
Osteonecrosis
Combined obesity and small bone
size in some women.
59. Management options for medial
compartment OA
HTO suitable for high-demand, young
patients
UKA (better functional results, much
better 10-year survival – 98% versus
66%)
Good after
My name is Banaszkiewicz
For this first section I will be taking you through examination of the hip
I have no disclosures to make
Nonoperative
strategies may include patient education, exercise,
weight loss, bracing, analgesia, non-steroidal antiinflammatory
drugs (NSAIDs) and possibly intra-articular
(IA) injections. Although many of these treatment methods
are employed the evidence for their benefit is mixed.
Opening wedge. The weight-bearing line is determined by measuring from the point located at 62.5% of the width of the tibial plateau to the center of the femoral head and from that point on the tibial plateau to the center of the ankle. The angle formed at the intersection of these lines (ie, α angle) represents the angle of correction. The osteotomy line (ab) is defined from medial (≈4 cm below the joint line [a]) to lateral (tip of the fibular head [b]). The line segment ab is transferred to the rays of the α angle from the vertex to obtain line segments aibi and aic. The distance bic corresponds to the opening that should be achieved medially at the osteotomy site. This distance is measured in millimeters.
Tibial bone varus angle
(TBVA) is the angle between a
line from the centre of the tibial
spines to a point midway the
proximal tibia epiphysis, and
the mechanical axis line of the
Planning of a medial closing-wedge supracondylar
osteotomy.
A) The present mechanical axis is drawn from A, the
center of the femoral head, to B, the centre of the ankle
joint. Line B-C is of equal length as line A-B and passes the
knee just medial of the medial eminence representing the
desired postoperative mechanical axis.
B) The hinge point of the osteotomy (D) is marked just
proximal from the upper border of the lateral condyle and
0,5−1 cm within the lateral cortex. The angle of correction
(α) is defined by line A-D between the present femoral
head centre and the hinge point and line C-D connecting
the new femoral head center position and the hinge point.
C) Correction angle α is projected at the distal femur using
two oblique down sloping lines of equal length converging
at the hinge point. The distance measured between those
2 lines at the level of the medial cortex (arrows) represents
the osteotomy wedge base length to be removed during
surgery.