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TKA Other Complications

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Topic updated on 05/14/16 5:57pm
Introduction
  • TKA Complications discussed in this topic
    • vascular injury
    • wound complications
    • metal hypersensitivity
    • heterotopic ossification
    • blood loss and anemia
  • TKA Complications in other topics
    • periprosthetic infection 
    • periprosthetic fracture 
    • patellar clunk  
    • patellar maltracking
    • instability (tibio-femoral)
    • stiffness
    • extensor mechanism rupture
    • neurologic injury (peroneal nerve)
Patellar Component Loosening
  • Introduction 
    • epidemiology
      • 0.6-5% of cases
        • more common with metal-backed patellae
    • etiology
      • subclinical infection
      • maltracking or overstuffing, leading to high shear
    • risks
      • obesity
      • lateral release
      • joint-line elevation
      • postoperative flexion >100°
      • poor bone stock
      • asymmetric patellar resection
      • inadequate implant fixation (small pegs)
      • secondary osteonecrosis and osteolysis
  • Imaging
    • radiographs
      • lateral view
        • show patellar component adjacent/superficial to patella
        • show loss of radiolucent space in patellofemoral joint and contact between patella bone and femoral component
  • Treatment
    • revision of patellar component
      • if revision fails, resection of patellar component
Vascular Injury
  • Introduction
    • incidence
      • .017%-.2%
    • risk factors 
      • sharp dissection in posterior compartment of knee
      • posterior retractor placement
        • stay medial with retractor
      • pre-existing vascular disease
    • causes
      • direct laceration
      • thrombosis
  • Anatomy
    • lateral structure as it crosses knee
    • 1 cm off tibial plateau in extension
    • 2 cm off tibial plateau in flexion
  • Treatment
    • immediate vascular surgery consultation
Wound Complications
  • Introduction
    • risk factors 
      • systemic factors
        • DM II
        • vascular disease
        • rheumatoid arthritis
        • certain medications
        • tobacco
        • poor nutritional status
        • albumin <3.5g/dL
        • total lymphocyte count <1,500/uL
        • perioperative anemia
        • obesity
      • local factors
        • previous incisions
          • skin bridges should be >5-6cm
          • avoid crossing previous skin incisions at an angle <60 degrees
        • knee deformity
        • skin adhesions
        • poor local blood supply
      • technique
        • large subcutaneous skin flaps
        • not preserving subcutaneous fat layer
      • postoperative
        • hematoma
        • infection
  • Evaluation
    • must rule-out infection
  • Treatment
    • debridement and coverage with rotational flap 
      • indications
        • full-thickness necrosis
Metal Hypersensitivity
  • Introduction
    • incidence
      • rare
    • cause
      • nickel found in cobalt-chromium alloys
  • Evaluation
    • patch testing
    • lymphocyte transformation test (LST)
  • Treatment
    • revise to nonallergenic metal prosthesis
Heterotopic Ossification
  • Introduction
    • incidence
      • less frequent than after THA 
    • risk factors 
      • periosteal stripping off anterior femur
      • male gender
      • obesity
      • post traumatic deformity
Blood Loss & Anemia
  • Risk factors
    • closed suction drainage
      • associated with increased incidence of transfusion 

 

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Qbank (5 Questions)

TAG
(OBQ11.126) A patient undergoes the procedure depicted in Figures A and B with standard components (non-gender specific). Which of the following outcomes most appropriately describes the difference in females compared to males for this procedure? Topic Review Topic
FIGURES: A   B        

1. Greater implant survivorship
2. Decreased WOMAC scores
3. Increased rate of extensor mechanism rupture
4. Increased postoperative pain
5. Increased component osteoloysis

PREFERRED RESPONSE ▶
TAG
(OBQ10.270) A 55-year-old patient is scheduled for total knee arthroplasty. A radiograph is provided in Figure A. Each of the following are risk factors for heterotopic ossification EXCEPT? Topic Review Topic
FIGURES: A          

1. Incorrect sizing of femoral and/or tibial components
2. Male gender
3. Obesity
4. History of trauma
5. Presence of preoperative osteophytes (hypertrophic arthrosis)

PREFERRED RESPONSE ▶
TAG
(OBQ05.142) A 65-year old healthy male has just undergone primary total knee arthroplasty. Which of the following is associated with use of a closed suction drain in this procedure? Topic Review Topic

1. Increased incidence of wound dehiscence
2. Increased incidence of transfusion
3. Decreased incidence of infection
4. Decreased incidence of hematoma formation requiring return to OR
5. Decreased pain scores on post-op days 1 and 2

PREFERRED RESPONSE ▶
TAG
(OBQ04.103) A 62-year-old female underwent a primary total knee arthroplasty of the left knee 10 days ago. She presents to clinic with skin necrosis of the midline incision. There is no deep infection present upon aspiration of the knee joint. She undergoes superficial irrigation and debridement and is left with exposed patellar tendon as shown in Figure A. What is the most appropriate next step in management? Topic Review Topic
FIGURES: A          

1. Split thickness skin grafting
2. Twice daily wet-to-dry dressing changes with Dakin's solution until healing by secondary intention
3. Latissimus dorsi free flap transfer
4. Vacuum-assisted closure device until healing by secondary intention
5. Medial gastrocnemius muscle flap transfer and skin grafting

PREFERRED RESPONSE ▶
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Cases

http://upload.orthobullets.com/cases/2339/2ebeb8fc-99c6-4859-a899-21b38711174c_intraop_2.jpg http://upload.orthobullets.com/cases/2339/bd59b4cf-a85f-44b6-921c-36ee3d7fd5bc_intraop.jpg http://upload.orthobullets.com/cases/2339/7c15da2a-f49c-4c8b-bc72-1dd7e1a260d0_dsc_0024_copy.jpg
HPI - 64 YRS 110 KG MALE PATIENT WAS OPERATED( TOTAL KNEE REPLACEMENT ) FOR RIGHT KNEE...
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