GOUT UPDATE AHMED YEHIA 2024, case based approach with application of the lat...
practical tips in planning TKR
1. Practical tips on preoperative
planning and workup in
Basic TKA workshop
Dr Smarajit Patnaik DNB
Senior Consultant, Orthopaedics and Joint Replacement
Apollo Hospitals, Bhubaneswar
2. The John Insall Award:
Patient expectations affect satisfaction with total knee arthroplasty.
Noble PC , Conditt MA, Cook KF, Mathis KB.
An unhappy patient can be an unhappy TKR and spoil everyone’s
happiness.
3. Please be careful with a patient with symptoms out of
proportion to that seen in the X rays
4. Patients less than 60 years at the time of surgery are at higher risk of
residual pain after TKR
Their activity levels are high, expectations out of surgery are high
5. • Psychological distress in the form of anxiety and depression can
influence pain even after surgery.
• Poor coping skills (PCS score) and a lack of social support can affect
the outcome of TKR.
6. Identifying unhappy patients
With unrealistically high expectations and counseling them
With Diabetes, Pulmonary disease and concomitant Back pain requiring
oral medication are predictors of dissatisfaction after TKR.
7. Primary Indication
Is to relieve pain caused by severe arthritis
The pain should be significant and disabling
….. and affecting quality of life
Night pain is distressing and significant
9. One single important view for Clinico-radiological
correlation.
Standing X rays AP view, Lateral view and skyline view of patella of both knees
12. • Assessment of hip–knee–ankle (HKA) axis to determine the distal valgus cut in the
absence of computer assisted systems (CAS).
• Deviations from normal alignment:
• Evaluation of offset (e.g., post high tibial osteotomy (HTO) cases).
• Identifying deformity and predicting its correctability; evaluating need of releases for the
deformities.
• Extra-articular deformities (e.g., posttraumatic, developmental tibia vara, etc.) to identify site of
deformity, and calculate approximate contribution of that to the joint.
• Variation in Anatomy: narrow mediolateral width of distal femur in ‘female-type’ knees
may warn surgeon to consider deep-dish design over cam and post, in order to avoid box
cut.
• Bone loss or defects, which may demand augments, cones, metal blocks,
• Variation in femoral neck shaft angle, femoral bowing, or previously performed total hip
arthroplasty may affect the distal valgus cut, hence x ray pelvis with both hips
15. Consenting
• DVT
• PE
• Infection
• CVA or MI
• Fractures intra and post op
• Vascular injury
• Instability of the replaced knee
16. Pre operative evualation
• Soft tissue status around the knee
• Vascular status of the limb
• Extensor mechanism
• Pre operative range of motion
17. Selecting a prosthesis
• Tricompartmental disease, younger patient, less than 10 to 15 degrees of
deformity which is correctable is a great case for CR knee.
Should we do a posterior stabilized knee in all our cases or should we think ,
Is it less constrained than a PS knee? Does it have a better survivorship!
• If the PCL is not intact or is violated then one can do the Deep Dish type of
poly, which is an an anterior stabilized knee. It is more constrained in
anteroposterior axis than a CR knee.
• Deformity is more than 10 to 15 degrees, inflammatory arthritis, post HTO
knees, patellofemoral OA changes, balancing the PCL may be difficult
because of the big posterior osteophytes, more soft tissue release to
balance the gaps is a proper case for PS knee.
18. MOBILE BEARING OR FIXED BEARING
• In 1998, John Insall stated, ‘The kinematic conflict between low stress
articulations and free rotation cannot be solved by any fixed bearing
design. ...
• Patients with significant coronal deformity, 20° of valgus, and 25–30°
of varus may not have the adequate remaining soft tissues needed to
create well-balanced flexion and extension gaps necessary to prevent
instability and possible spinout.
• Now since the patients are younger, heavier and more active, along
with having increased life expectancy, there is a need for increased
TKA implant survivorship, functional performance and load tolerance.
19. • If there is further more instability and the deformity is more, regional
osteoporosis, if the gaps are larger, and we have to use thicker poly
with bigger post and cam then we have to use stem extenders and
Condylar constrained knees like TC3 or LCCK systems are preferred.
These are basically two revision systems
• When collateral insufficiency is more or an MCL deficient knee or a
neuropathic joint in a primary case, use a hinge prosthesis
• Periprosthetic fractures in osteoporotic bones unsalvageable , bone
tumors for limb salvage are good for tumor prosthesis
21. “the surgeons’ goals”
1. Recreating limb alignment and a neutral mechanical axis
2. Balancing the soft tissue sleeve that surrounds the knee
3. Creating normal knee movement or “kinematics”
For the result to be optimal after TKR, these three conditions need to
be met.
However, it must be kept in mind that the width of the distal femur may not be always appreci- ated well in a plain X-ray (e.g., in a knee with flexion deformity, distal femur may appear broader due to the oblique projection of X-ray beams).