jueves, 7 de junio de 2012

Smoking Threatens Orthopaedic Outcomes

Negative effects should prompt orthopaedists to address the issue with patients
S. Terry Canale, MD; Frank B. Kelly, MD; and Kaye Daugherty
Although the prevalence of smoking has decreased dramatically in the United States during the past 50 years, this decline has not translated into a decline in the health problems associated with smoking. The deleterious effects of smoking on cardiovascular and pulmonary function are well known, as are the carcinogenic properties, and physicians in these disciplines have been at the forefront of smoking cessation efforts for their patients.
The negative effects of smoking on conditions of the musculoskeletal system, and treatment of these conditions, are less well documented, however, and most orthopaedic surgeons have been reluctant to discuss these with their patients. Accumulating evidence, however, makes it imperative for orthopaedic surgeons to face this problem and find ways to help patients who smoke to quit.
At the AAOS Now-sponsored Perioperative Smoking Cessation Forum, held in San Francisco in February, researchers noted that patients who quit smoking have improved outcomes for surgical and nonsurgical treatments of musculoskeletal conditions and injuries. Their studies provide convincing reasons for orthopaedic surgeons to become involved in helping patients to quit smoking.
Basic science studies
Several basic science studies have documented the effects of tobacco use on the musculoskeletal system at the cellular and molecular levels, including the development or worsening of intervertebral disk degeneration, osteoporosis, arthritis, and delayed ligament healing.
In a study replicating long-term cigarette use in humans, mice exposed to cigarette smoke had reduced disk matrix protein (proteoglycans). The intervertebral disks of young rats exposed to cigarette smoke developed disk cracks and fibrosis. In rabbits, exposure to cigarette smoke resulted in delayed healing and decreased torsional strength of the tibia after tibial lengthening.
Studies have also found that cigarette smoke condensate augmented the induction and development of arthritis and antibody levels against collagen. Reported effects at the molecular level include decreases in cellular density and type I collagen, DNA damage, an increase in inflammatory cytokines, loss of the extracellular matrix, cellular senescence, cell death, and decreased cell proliferation.
Clinical studies
Clinical studies have found equally deleterious effects of cigarette smoking in patients with a variety of musculoskeletal conditions and procedures. Smoking, along with male sex and diabetes, has been identified as a significant risk factor for surgical site infection in orthopaedic procedures performed in an ambulatory surgical center. Smoking may be the single most important factor in postoperative complications.

Worse outcomes and more frequent complications have been found in smokers who have spinal surgery at any level and for any pathology. One study of patients who had surgery for lumbar spinal stenosis found less improvement in walking ability and more regular use of analgesics among smokers than nonsmokers. A study of patients treated for thoracolumbar fractures found that smokers were 13 percent more disabled and 11 percent less satisfied than nonsmokers. Smokers with multilevel cervical spine decompression and fusion have worse clinical outcomes and less frequent fusion than nonsmokers. Tobacco use has been identified as a significant predictor of postoperative infection in patients who have spinal surgery.

Not only does smoking affect outcomes of spinal surgery, it appears to contribute to the development of spinal conditions that require surgery. Associations have been found between the number of pack-years of smoking and the development of lumbar disk herniation and between smoking and the progression of spondylolisthesis, an earlier onset of inflammation, and poor function and quality of life in smokers.
The association between tobacco use and worse outcomes and more frequent complications has also been confirmed in studies of total joint arthroplasty, fracture healing, hand and foot surgery, ligament and cartilage repair, and the development of osteoporosis and rotator cuff pathology. Several studies have reported increased risks of surgical site infections and wound breakdown after total knee (TKA) or total hip arthroplasty (THA) in smokers. Smokers have a greater risk of implant loosening, longer operative times, and higher hospital charges than nonsmokers.
The delayed fracture healing suggested by basic science studies also has been exhibited in clinical studies. A study of patients with open tibial fractures found that smokers had a longer time to fusion, more complications, and a lower union rate than nonsmokers. The risk of impaired bone healing in tibial shaft fractures has been estimated at 3 to 18 times higher in smokers. The results of a multicenter, randomized, controlled trial found that the odds of having a complication after a fracture of the upper or lower extremity was 2.5 times higher in smokers than in nonsmokers and rates of superficial infection in smokers were more than double those in nonsmokers.
After transmetatarsal amputation, bunionectomy, and hindfoot fusion, smokers have slower healing rates than nonsmokers. The impact of smoking on outcomes after hand surgery has also been reported. Smoking is associated with surgical site infections after hand surgery and with scaphoid fracture nonunions; the risk of nonunion is almost 4 times greater among smokers than nonsmokers.
Delayed healing in smokers also has been reported after anterior cruciate ligament repair, cartilage restoration procedures, and arthroscopic repair of hip labral tears. Tobacco use also has been cited as a factor in lower bone mineral density and the development of osteoporosis.
Does smoking cessation help?
Two recent meta-analyses in the nonorthopaedic literature clearly indicate benefits of smoking cessation in reducing postoperative complications. In the orthopaedic literature, studies have reported significant reductions in wound healing complications with at least 4 weeks of smoking cessation and a significant reduction in wound-related complications in TKA and THA patients who completed a 6- to 8-week smoking cessation program before and/or after surgery.
A study of patients who underwent hindfoot fusions found that those who quit smoking before surgery had a lower rate of nonunion than smokers. A 2010 Cochrane Database Review concluded that smoking cessation interventions beginning 4 to 8 weeks before surgery could significantly reduce postoperative complications.
What is the orthopaedist’s role?
Most patients, if properly informed, want help to quit or reduce smoking before their surgery. An informal survey of patients who smoked found that 85 percent would be willing to start a supervised smoking cessation program before surgery. In another group of patients facing foot or ankle surgery, 64 percent quit smoking and 16 percent reduced the rate of their smoking with encouragement and counseling before surgery.
Orthopaedists need to realize that they are the most important factor in any smoking cessation program. A patient who is considering a surgical procedure presents the orthopaedic surgeon with a “teachable moment.” In a group of more than 10,000 patients scheduled for spinal surgery, 36 percent quit smoking when their surgeons made smoking cessation a high priority.
The simple act of asking the patient about his or her tobacco use and explaining the increased risk of complications provides motivation to enter a smoking cessation program—and may encourage as many as one in five patients to stop smoking. According to Nancy Rigotti, MD, of the Tobacco Research and Treatment Center at Harvard, the following three-step approach is very effective:

Ask the patient about his or her smoking status.
Advise the patient to stop smoking.
Refer the patient to appropriate assistance programs.

Although the most effective smoking cessation program has yet to be determined, most use some combination of the following:

counseling
a dedicated “quitline”
regular follow-up contact
nicotine replacement therapy (NRT)
pharmaceutical support

The safety and efficacy of NRT and pharmaceutical support is still being debated. Some suggest that NRT should not be used because it may impede bone and wound healing. Basic science studies have shown that total smoke (cigarette smoke condensate) is worse than nicotine alone. Although nicotine may lead to cell death and the use of NRT may contribute to disk degeneration, no evidence in humans supports a negative effect of NRT. Clearly, however, long-term support, with or without NRT, provides the best chance for lasting smoking cessation.
The deleterious effects tobacco use has on patients’ overall health and specifically the outcomes of orthopaedic conditions and their treatment make it imperative that orthopaedic surgeons join other specialties in increasing patient awareness and instituting programs to help patients quit smoking. As noted by Dr. Olle Swenson of the Swedish Orthopaedic Association, whose work in smoking cessation is internationally known, smoking cessation is not a moral issue but an issue of patient safety.
So what can the orthopaedist do?

Recognize the problem. Orthopaedists need to be aware of the deleterious effect of tobacco use on musculoskeletal health and on the outcomes of musculoskeletal procedures.
Ask the question. Simply asking patients about their smoking status increases the chances of smoking cessation.
Advise the patient. Concerns about the effects of tobacco use on any planned orthopaedic treatments need to be conveyed clearly and concisely to the patient, along with information about available smoking cessation programs and support. A discussion about delaying elective surgery until the patient has quit smoking may be appropriate.

To eliminate one of the frequently cited excuses for not discussing smoking cessation—“I don’t know how”—a number of free or low-cost resources are available for physicians and patient education and support are listed at the end of this article.

Refer the patient. Orthopaedists need to be informed about available assistance for their patients who want to quit smoking (including therapies and programs such as NRT, pharmaceuticals, Quitlines, and support groups). Patients should be referred to other physicians or groups who can provide such support.
Follow the progress. At every appointment, the orthopaedist and his or her staff should ask about the patient’s progress in quitting smoking, encourage efforts to do so, and re-emphasize the importance of smoking cessation on the patient’s musculoskeletal health.

S. Terry Canale, MD, is editor-in-chief of AAOS Now; Kaye Daugherty is the medical editor for the Campbell Foundation; Frank B. Kelly, MD, is a member of the AAOS Now editorial board.
Taking Smoking Cessation a Step Farther
At the AAOS Now-sponsored Perioperative Smoking Cessation Forum, held during the 2012 AAOS Annual Meeting in San Francisco, experts in the field reviewed the evidence and discussed steps orthopaedic surgeons can take to reduce tobacco use among their patients and improve outcomes of treatment of musculoskeletal disorders.

In addition to individual orthopaedists, national, regional, and local groups should have a part in this effort. For example, at the national level, the following steps could be taken:
Initiate an awareness campaign for orthopaedic surgeons to make them more aware of the poor results in orthopaedic surgery secondary to smoking and encouraging them to ask, advise, and refer their patients for smoking cessation.
Develop a consensus statement on smoking cessation (perhaps by a patient safety committee).
Encourage research to determine the effect of nicotine-replacement therapy on orthopaedic surgical results.

At the state and local levels, the following steps would be helpful:

Provide information on referral patterns available in the state, city, and community.
Make available patient hand-outs on smoking cessation and different types of referral sources.

Additional Resources

AAOS Now
June 2012 Issue
http://www.aaos.org/news/aaosnow/jun12/cover2.asp