Sternal instability, infection, and wound dehiscence are among the primary complications of median sternotomy. Although the incidence of complications is rare, rates of subsequent morbidity and mortality are high. This makes proper healing of the sternum a priority for ensuring good patient outcomes.
Traditional Sternal Precautions
There is no universal definition of sternal precautions. As a result, the type and duration of activity restrictions vary widely across facilities. Common elements include:
- No lifting more than 5-10 lbs;
- No reaching behind the back; and
- No pushing or pulling through the arms.
Additional instructions may prohibit reaching overhead with one or both arms, or driving. Recommended adherence can last anywhere between 4 to 12 weeks.
The video below shows strategies that may be used to mobilize patients with traditional sternal precautions:
Evidence supporting the efficacy of traditional sternal precautions is low. For the most part, precautions are based on anecdotal evidence, expert opinion, and cadaver studies. Multiple reviews suggest that traditional practice is overly restrictive and may lead to negative outcomes such as disuse atrophy and kinesiophobia (fear of movement).
Modified Sternal Precautions
In recent years, researchers have proposed less restrictive sternal precautions. Cahalin et al. recommend using risk classifications to prescribe appropriate levels of restriction. From there, they suggest patient presentation be used to guide a progressive return to activities. Likewise, Adams et al.  advocate a set of recommendations known as "Keep Your Move In The Tube." It encourages patients to perform unloaded arm movements within a pain free range of motion. In addition, loaded arm movement is permitted as long as the upper arms stay close to the body; load progression is informed by patient tolerance. The following video describes these recommendations and some of the proposed benefits in more detail:
Finally, Brocki et al. compiled evidence regarding risk factors for sternal complications and sources of mechanical stress to make seven recommendations after sternotomy:
- Bilateral movements of the arms in the horizontal level, backwards or over the shoulder level, should only be performed within pain-free limits during the initial 10 days following sternotomy or until the wound is healed.
- Loaded movements of the arms should only be done at a pain-free level.
- In general, patients should keep the upper arms close to the body for 6-8 weeks.
- Patients with BMI≥35 should wear a supportive vest to protect the sternum for 6-8 weeks.
- Patients should be taught to hug a pillow over the surgical incision when coughing and sneezing for 6–8 weeks.
- Patients who cough frequently should wear a sternal vest supporting the entire circumference of the thorax.
- Patients with large breasts should use a supportive brassiere that fastens in the front.
In summary, modified sternal precautions acknowledge that the relationship between arm movement, pain, and mechanical stress to the sternum is inconsistent. As a result, modified guidelines place less emphasis on strict avoidance of specific activities and more emphasis on patient characteristics and presentation.
Direct evidence for the use of modified sternal precautions is limited. To date, Katijjahbe et al. have performed the only randomized control trial comparing standard restrictive sternal precautions to modified sternal precautions. They found no difference in rates of sternal complications or patient outcomes (pain, physical function, upper limb function, quality of life, kinesiophobia), suggesting that less restrictive precautions may be a suitable alternative to traditional practice.
Physical therapy professionals should refer to the policies of their treating institution to determine how and when to apply sternal precautions. Common interventions for patients with sternal precautions may include:
- Patient education on sternal precautions, signs of infection, and signs of sternal instability (excessive movement of the sternum, clicking or popping, difficulty performing functional tasks)
- Functional mobility (ex. bed mobility, transfers, gait)
- Activities of daily living (ex. toileting, dressing, and other lifting or reaching activities)
- Caregiver training
- Pain control (ex. hugging a pillow over the surgical incision when coughing or sneezing)
- Safe exercise for the upper and lower extremities
Clinicians involved in developing and revising hospital protocols may use emerging evidence to advocate for the use of modified sternal precautions over traditional, more restrictive alternatives.
- Losanoff JE, Richman BW, Jones JW. Disruption and infection of median sternotomy: a comprehensive review. European journal of cardio-thoracic surgery. 2002 May 1;21(5):831-9
- Cahalin LP, LaPier TK, Shaw DK. Sternal precautions: is it time for change? Precautions versus restrictions–a review of literature and recommendations for revision. Cardiopulmonary physical therapy journal. 2011 Mar;22(1):5.
- Brocki BC, Thorup CB, Andreasen JJ. Precautions related to midline sternotomy in cardiac surgery: a review of mechanical stress factors leading to sternal complications. European Journal of Cardiovascular Nursing. 2010 Jun;9(2):77-84.
- Adams J, Lotshaw A, Exum E, Campbell M, Spranger CB, Beveridge J, Baker S, McCray S, Bilbrey T, Shock T, Lawrence A. An alternative approach to prescribing sternal precautions after median sternotomy,“Keep Your Move in the Tube”. In Baylor University Medical Center Proceedings 2016 Jan 1 (Vol. 29, No. 1, pp. 97-100). Taylor & Francis.
- El-Ansary D, Waddington G, Adams R. Relationship between pain and upper limb movement in patients with chronic sternal instability following cardiac surgery. Physiotherapy theory and practice. 2007 Jan 1;23(5):273-80.
- Irion GL, Gamble J, Harmon C, Jones E, Vaccarella A. Effects of upper extremity movements on sternal skin stress. Journal of Acute Care Physical Therapy. 2013 Jan 1;4(1):34-40.
- Katijjahbe MA, Granger CL, Denehy L, Royse A, Royse C, Bates R, Logie S, Ayub MA, Clarke S, El-Ansary D. Standard restrictive sternal precautions and modified sternal precautions had similar effects in people after cardiac surgery via median sternotomy (‘SMART’Trial): a randomised trial. Journal of physiotherapy. 2018 Apr 1;64(2):97-106.