Please rate topic.
Average 4.3 of 41 Ratings
Thank you for rating! Please vote below and help us build the most advanced adaptive learning platform in medicine
A 61-year-old male had a minimally-invasive unicompartmental knee replacement 8 months ago. He did well until recently when he developed persistent right knee pain that is worse with weight bearing. He denies any fevers or recent trauma. He does report that he had been exercising more over the past few months in an attempt to lose weight. WBC, ESR and C-reactive protein levels are normal. An AP radiograph and bone scan are shown in Figure A and B. What is the most likely cause of his symptoms?
Component failure/ polyethylene failure
Pes anserine bursitis
Complex regional pain syndrome
Select Answer to see Preferred Response
All of the following are contraindications to medial unicondylar knee arthroplasty EXCEPT:
Flexion contracture greater than 10 degrees
Varus deformity greater than 10 degrees not correctable with stress testing
Lateral knee joint line pain
Osteonecrosis of the medial femoral condyle
A 40-year-old man has moderate lateral compartment arthritis several years after undergoing a partial lateral meniscectomy. He has a correctable 5 degree valgus knee deformity compared to his other limb. His patellofemoral and medial compartments do not show any radiographic signs of degenerative changes. His knee has full range of motion and is stable on exam. After failing nonoperative treatments, which surgical option is most likely to give him the best outcome?
Valgus producing high tibial osteotomy
Varus producing distal femoral osteotomy
Total knee replacement
Arthroscopic debridement and chondroplasty
Tibial tubercle osteotomy with anteromedialization
Figure 53a shows the AP radiograph of a 70-year-old patient who is scheduled to undergo unicompartmental knee arthroplasty. Figure 53b shows the immediate postoperative radiograph, and the radiograph shown in Figure 53c, obtained 6 months after surgery, shows a medial tibial plateau fracture. The etiology of the fracture is best related to
reduced contact area of a unicompartmental knee arthroplasty for load transmission.
excessive medial placement of the tibial component of the unicompartmental knee arthroplasty.
multiple drill holes that violate the medial cortex.
osteonecrosis of the medial tibial plateau.
Which of the following is the strongest contraindication to unicompartmental knee arthroplasty (UKA)?
Patient age of younger than 60 years
Patient age of older than 80 years
Anterior cruciate ligament (ACL) deficiency
Varus deformity of 5 degrees
Outerbridge grade II chondromalacia of the patella
Figure 15 shows the radiograph of an active 60-year-old woman. Which of the following variables is considered the strongest contraindication to a unicompartmental knee arthroplasty in this patient?
Fixed varus deformity of more than 15 degrees
Five degree flexion contracture
Contralateral knee osteoarthritis
Joint subluxation of 5 mm
All of the following are contraindications for a medial unicompartmental knee replacement EXCEPT?
Anterior compartment osteophytes and pain beneath the patella
Medial sided knee pain with medial and lateral compartment osteophytes and 3 degrees of varus deformity
Lateral sided knee pain with degenerative changes isolated to the medial compartment and 7 degrees of varus deformity
Flexion contracture of 3 degrees
Which of the following benefits can be expected from unicompartmental knee arthroplasty compared to total knee arthroplasty for medial compartment knee arthritis?
Better clinical outcomes at one year follow-up.
Greater survivorship rate at 10 year follow-up
Faster postoperative rehabilitation
Better postoperative knee alignment
Reduced risk of secondary surgery within the first year
When performing a unicondylar knee replacement, a smaller incision without dislocation of the patella offers what advantage over a standard, patella-everting approach?
the option to convert to a total knee arthroplasty if needed
more anatomic positioning of the components
better ultimate range-of-motion
increased 10-year implant survival rate
improved rate of recovery
With regards to unicompartmental knee arthroplasty, all of the following are true EXCEPT:
Females have a higher revision rate
BMI greater than 32 is not a risk factor for early implant failure
Presence of osteopenia contributes to premature implant failure
Lateral compartment arthroplasties have higher failure rates than medial compartment arthroplasties
Progressive arthritis within the remaining compartments of the knee is low 5 years post-operatively
A 60-year-old male tennis player undergoes a unicompartmental knee arthroplasty (UKA) shown in Figures A and B. Which of the following statements regarding this procedure is true?
Compared to total knee arthroplasty (TKA), UKA more closely approximates native knee kinematics
Patients undergoing a UKA and TKA have equivalent blood loss and pain medication requirements
Compared to their TKA counterparts, UKA patients have a slower return to function
There is no difference in range of motion at short or long term follow-up when compared with TKA
Postoperative hospital stay is equivalent for UKA and TKA patients