Smoking Associated with Hip and Knee Replacement Failure
Tobacco and nicotine use are known to impair the body's ability to heal bones and wounds. Two new studies presented at the 2012 Annual Meeting of the American Academy of Orthopaedic Surgeons looked at the effects of smoking on total joint replacement. A separate Smoking Cessation Forum featured expert testimony on how orthopaedic surgeons may successfully encourage and aid patients in quitting smoking, optimally before surgery.
The first study, "Increased Revision Rates Following Total Knee Arthroplasty in Patients Who Smoke," found that patients who smoke before and/or after total knee replacement (TKR) surgery had a 10-fold higher revision rate compared to non-smokers.
The investigation involved 621 TKR patients, including 131 smokers (median age 62). All patients who were smokers were encouraged to participate in a smoking cessation program prior to TKR surgery. Clinical outcomes, including pain, function and range of motion, were assessed following surgery in both groups. The smoking group had 13 knee replacement failures (10 percent) compared to five in the non-smoking group (1 percent).
The medical complication rate also was "significantly higher" in the smoking group, with 27 patients (21 percent) having a medical complication compared to 60 (12 percent) of non-smokers. Complications included deep venous thrombosis (DVT) or blood clots, anemia requiring treatment, cardiac problems, and acute renal failure. Investigators recommend that patients stop or minimize nicotine use prior to TKR.
The second study, "Smoking is a Harbinger of Early Failure with Ultraporous Metal Acetabular Reconstruction," looked at the effects of smoking on patients who underwent reconstruction of the acetabulum – the cup shaped cavity at the base of the hip bone – with ultraporous metal. In general, the newer materials have resulted in increased survival rates and fewer hip replacement failures than other implants made from standard porous metal.
Between 1999 and 2009, ultraporous acetabular components were used in 533 hip replacements, including 159 primary and 374 revision surgeries. Of these patients, 17 percent were smokers, 31 percent previous smokers, 50 percent non-smokers, and 3 percent unknown. The failure rate in smokers was 9.1 percent, compared to 3.4 percent in non-smokers. Investigators recommend that orthopaedic surgeons strongly advocate for smoking cessation before surgery to ensure optimal recovery and outcome.
During the Smoking Cessation Forum, experts provided testimony on the harmful ingredients and outcomes associated with smoking. Patients who quit smoking before and during orthopaedic treatment have less pain than those who smoke, but also better outcomes.
For more information about the American Academy of Orthopaedic Surgeons, visit aaos.org.