Outcomes After Total Knee Joint Arthroplasty : A Comparative Study Using 3 Different Analgesic Techniques

• Primary outcome - incidence of global adverse events [ Time Frame: 3 months ] [ Designated as safety issue: Yes ]
  A composite rate of perioperative adverse events, including MI, DVT/PE, delirium, pneumonia, paralytic ileus, GI bleed, new onset renal dysfunction, wound infection will be used.
  
  

• Perioperative pain [ Time Frame: Every 6 hours up to a total of 72 hours. ] [ Designated as safety issue: No ]
  Postoperative pain levels on a visual analogue scale will be recorded while the patient is an inpatient up to a maximum of 72 hours.
  
  
• Postoperative mobility [ Time Frame: Measured at day 3, 1 month and 3 months. ] [ Designated as safety issue: No ]
  Postoperative mobility will be assessed by a blinded physiotherapist using the 'Timed up-and-go' or 'TUG' test. This test assess how long it takes for a patient to rise from a chair, walk a fixed distance then return and sit again.
  
  
• Skin hypersensitivity [ Time Frame: 3 and 6 months post operation. ] [ Designated as safety issue: No ]
  Skin hypersensitivity will be assessed using Von Frey hair technique at 3 and 6 months postop, and the area in square millimetres recorded.
  
  
• Patient reported pain, stiffness and functional disability. [ Time Frame: Assessed preoperatively, and at 1 and 3 months postoperative. ] [ Designated as safety issue: No ]
  These variables will be assesed using the Western Ontario and McMaster Universities Arthritis Index (WOMAC score).
  
  

Our objective is to compare the three analgesic regimes for total knee joint arthroplasty currently practiced at our institution with regard to their impact on patient outcomes in the immediate postoperative period and for up to 6 months. The outcome measures that we will be prospectively looking at are:

A. Pain and functional outcomes: Twice a day pain scores following activity during the in hospital stay, number of days that patient requires oral narcotics, presence of complex regional pain syndrome, presence and extent of wound hyperalgesia at 3 months, WOMAC scores preoperatively and at 6weeks and 3 months. 'Timed up and go' test will be performed on day 3 or at discharge and at 2 weeks and 3 months. Incidence of falls while in hospital and following discharge.

B. Specific non pain outcomes Cardiac: Myocardial infarction, myocardial ischemia, Congestive failure, new onset arrhythmia, death Respiratory: Hypoxia requiring supplemental oxygen beyond 24 hours, pneumonia, pneumonia requiring prolonged hospital stay CNS: postoperative delirium, cerebrovascular accident DVT: symptomatic DVT, asymptomatic DVT, Pulmonary emboli Infection: wound infection, prosthetic infection, need for major plastic reconstructive surgery or amputation.

Incidence of nausea and vomiting. Incidence of urinary catheterization. C. Economic outcomes: Length of hospital stay, direct health care costs, patient satisfaction

Primary hypothesis (null):

Perioperative analgesia provided by femoral and sciatic catheters, or by peri-articular wound catheters does not reduce the rate of combined serious outcomes compared with analgesia provided by peri-articular infiltration alone..

Secondary hypotheses (null):

1. Perioperative analgesia provided by femoral and sciatic catheters or by peri-articular wound catheters does not improve functional recovery compared with analgesia provided by peri-articular infiltration alone.
2. Perioperative analgesia provided by femoral and sciatic catheters, or by peri-articular wound catheters does not reduce the cost of delivery of care compared with analgesia provided by peri-articular infiltration alone.
3. Perioperative analgesia provided by femoral and sciatic catheters or by peri-articular wound catheters is not improved compared with analgesia provided by peri-articular infiltration alone.