An article published in the Journal of Bone and Joint Surgery examines the differences between partial and total knee replacement for short term complications.
Researchers examined patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent total or unicompartmental knee replacement from 2005 to 2011. There were 29,333 patients who underwent elective primary knee surgery — 27,745 who underwent total knee replacement and 1,588 who underwent partial knee replacement.
There were 63.7 percent of the patients who were female and the average BMI was 32.8±7.3 for total knee replacement; for partial knee replacement, 55.3 percent of the patients were female and BMI was 31.5±6.5.
The researchers found:
1. Total complication rate did not differ significantly between the two groups. The complication rate for total knee replacement was 5.29 percent while the complication rate for partial knee replacement was 4.16 percent.
2. Deep vein thrombosis rates where significantly higher for the total knee replacement group. The DVT rate was 1.5 percent for total knee replacement and 0.5 percent for partial knee replacement patients.
3. Hospital stays were also longer for the total knee replacement group — 3.4 days compared with 2.2 days for the partial knee replacement group. However, there are some surgeons now who are performing both partial and total knee replacements as outpatient procedures, some even in the ambulatory surgery center setting where traditionally complication rates are lower than in the hospital.
4. The American Academy of Orthopaedic Surgeons released clinical guidelines on the prophylaxis of venous thromboembolism, a risk for total joint replacements. The guidelines were designed to prevent the complication in patients, and study authors in another JBJS article examined their effectiveness. There were 3,289 patients examined at a single institution and 36 major VTE events. Risks included:
• History of blood clots
• Family history of blood clots in the proximal part of the thigh
• Pulmonary embolism
5. The 90-day incidence of VTE was 1.46 percent for total knee replacement patients—significantly higher than 0.56 percent for total hip replacement patients. The variation persisted despite comparable prophylaxis with enoxaparin sodium for 28 days.
"The prospective use of the first-generation American Academy of Orthopaedic Surgeons guidelines resulted in a low incidence of clinically important thromboembolic events in total hip and total knee arthroplasty patients," concluded the study authors. "When properly used in these patients, the guidelines to minimize adverse outcomes are executable and effective."