25 – Does post-operative rehabilitation protocol such as early ambulation influence the incidence of VTE after orthopaedic procedures?

Clara Lobo, Kenneth Egol.

Response/Recommendation: It is the opinion of this group that early ambulation reduces the incidence of venous thromboembolism (VTE) after orthopaedic procedures.

Strength of Recommendation: Moderate.

Rationale: The evidence to date has been mixed on the impact of post-operative rehabilitation protocols that include early ambulation on the incidence of VTE after orthopaedic procedures.  Immobilization, frequently seen with orthopaedic procedures, or from orthopaedic injuries to the extremities is a risk factor for VTE1,2, especially in the elderly population (> 70 years old)3.  The quantity and duration of immobilization as it relates to the degree of risk for VTE are unknown and there is wide variability in the literature regarding the risk for VTE from reduced mobility.  Early research has shown that a loss of mobility for >3 days has been correlated with the presence of deep venous thrombosis (DVT) on ultrasound4,5.  In addition, an epidemiologic case-control study of DVT risk factors in 1,272 patients found that patients who were ambulatory had an increased risk of VTE development with a standing time of >6 hours (odds ratio [OR]=1.9) or resting in a chair or bed (OR=5.6)6.

Guidelines written for hip and knee arthroplasty from the American Academy of Orthopaedic Surgeons (AAOS) and the American College of Chest Physicians (ACCP) on current VTE prophylaxis do not provide specifics on the type of VTE prophylaxis to be used.  However, they do include recommendations on early ambulation7,8.  Early post-operative mobilization is also recommended by the European Society of Anaesthesiology and Intensive Care (ESAIC) as a general thromboprophylaxis measure for most low and high-risk procedures9.  Older guidelines recommended bed rest for patients who were diagnosed with a lower extremity DVT as there was concern that ambulation would cause clot dislodgement leading to further complications such as a pulmonary embolism (PE).  However, recent findings of a meta-analysis that compiled 5 randomized control trials (RCT) with 3,048 patients showed that when compared to bed rest, early ambulation was not associated with a higher incidence of a new PE.  In fact, early ambulation was shown to be associated with a lower incidence of new DVT/PE compared to bed rest10.  A further systematic review assessing the impact of physical activity in patients with an acute or previous DVT of the leg found that early ambulation was safe in patients with acute DVT and helped prevent further complications11.  The physiological foundation for early ambulation is well understood following the principles of Virchow’s triad.  Nakao et al., reported that early postoperative ambulation was associated with lower levels of D-dimers in patients with osteoarthritis and rheumatoid arthritis following total knee arthroplasty (TKA)12.  However, the definition and duration of early ambulation varies across studies13.

Furthermore, several factors have a negative impact on early ambulation following surgery, such as low patient compliance due to postoperative pain, lack of intrinsic motivation, inadequate staffing, use of indwelling urinary catheter, acute complications, and specific hospital policies14.

There is some evidence to support the recommendation for early ambulation in postoperative orthopaedic patients.  Pearse et al.15, assessed the influence of a rapid rehabilitation protocol on TKA patients and the rate of DVT, as determined by Doppler ultrasound scanning on the fifth postoperative day.  The early mobilization group (beginning to walk < 24 h after knee replacement) was compared to a historical cohort.  In the early mobilization group, the incidence of DVT was considerably low 1.0% compared to 27.6% in the control group (p<0.001).  Husted et al.16, reported their results with short-duration pharmacological prophylaxis combined with early mobilization and reduced hospitalization protocol in 1,977 consecutive, unselected patients who were operated on for primary total hip arthroplasty (THA), TKA or bilateral simultaneous TKA (BSTKA) in a fast-track setting between 2004 and 2008.  Patients mobilized within four hours postoperatively and short duration of VTE prophylaxis (1- 4 days), had a mortality rate of 0% (95% confidence interval [CI] 0 to 0.5).  The incidence of DVT in the latter study was 0.60%, 0.51%, and 0.0% for patients undergoing TKA, THA, and BSTKA, respectively.  Based on these results, the authors indirectly concluded that early mobilization and short hospitalization are associated with lower VTE risks following arthroplasty and the principles of routine prolonged chemical thromboprophylaxis should be reconsidered.

In another small prospective study of TKA patients, 50 patients who underwent mobilization on the first postoperative day were compared with 50 patients who had strict bed rest on the first postoperative day.  The incidence of VTE in the mobilization group (seven in total) compared with the control group (16 in total) was significantly lower (p = 0.03).  Additionally, the odds of developing a thromboembolic complication was significantly reduced with greater walking distance17.  A multicenter retrospective cohort study in China found that early ambulation within 24 hours after TKA was associated with reduced length of hospital stay, improved knee function and range of motion, and lower incidence of DVT.  Interestingly, the incidence of pulmonary embolism did not differ between the early ambulation group and control group18.  Additionally, a VTE prevention team at Boston Medical Center designed a protocol that mandated early postoperative mobilization along with VTE risk stratification for patients and found an 84% reduction in the incidence of DVT over a two-year time period compared to the two years prior19.  Some of the reduction was correlated to the emphasis on early ambulation.  However, the patient demographics varied and were only based on general surgery and vascular surgery patients.

There are some studies demonstrating evidence to the contrary.  A RCT evaluating early functional mobilization on the incidence of DVT during leg immobilization after Achilles’ tendon rupture surgery found that early functional mobilization did not prevent the high incidence of DVT compared to expectant management20.  There is some thought that this is explained by postoperative pain and thus less weight-bearing.  In addition, another systematic review of five RCT examining the effect of early mobilization after THA or TKA found no differences in negative outcomes such as venous thrombosis in the control versus experimental groups21.  No studies reported negative outcomes associated with early postoperative mobilization.

In summary, there is some direct evidence to suggest that early mobilization following orthopaedic procedures may be protective against VTE, while some evidence suggests that early mobilization has no impact on VTE risk.  Given the low risk and cost associated with early mobilization, early ambulation is recommended in all patients, if clinical circumstances permit.  Additional RCT are needed to broaden the strength of recommendation, as well as to better quantify the duration of reduced mobility that leads to increased risk for VTE as well as the timing and duration of when to introduce early ambulation following orthopaedic procedures.


1.         Blom JW, Doggen CJM, Osanto S, Rosendaal FR. Old and new risk factors for upper extremity deep venous thrombosis. J Thromb Haemost JTH. 2005;3(11):2471-2478. doi:10.1111/j.1538-7836.2005.01625.x

2.         Rocha AT, Paiva EF, Lichtenstein A, Milani R, Cavalheiro CF, Maffei FH. Risk-assessment algorithm and recommendations for venous thromboembolism prophylaxis in medical patients. Vasc Health Risk Manag. 2007;3(4):533-553.

3.         Talec P, Gaujoux S, Samama CM. Early ambulation and prevention of post-operative thrombo-embolic risk. J Visc Surg. 2016;153(6S):S11-S14. doi:10.1016/j.jviscsurg.2016.09.002

4.         Hillegass E, Puthoff M, Frese EM, et al. Role of Physical Therapists in the Management of Individuals at Risk for or Diagnosed With Venous Thromboembolism: Evidence-Based Clinical Practice Guideline. Phys Ther. 2016;96(2):143-166. doi:10.2522/ptj.20150264

5.         Motykie GD, Caprini JA, Arcelus JI, et al. Risk factor assessment in the management of patients with suspected deep venous thrombosis. Int Angiol J Int Union Angiol. 2000;19(1):47-51.

6.         Samama MM. An epidemiologic study of risk factors for deep vein thrombosis in medical outpatients: the Sirius study. Arch Intern Med. 2000;160(22):3415-3420. doi:10.1001/archinte.160.22.3415

7.         Falck-Ytter Y, Francis CW, Johanson NA, et al. Prevention of VTE in orthopedic surgery patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e278S-e325S. doi:10.1378/chest.11-2404

8.         Jacobs JJ, Mont MA, Bozic KJ, et al. American Academy of Orthopaedic Surgeons clinical practice guideline on: preventing venous thromboembolic disease in patients undergoing elective hip and knee arthroplasty. J Bone Joint Surg Am. 2012;94(8):746-747. doi:10.2106/JBJS.9408.ebo746

9.         Afshari A, Ageno W, Ahmed A, et al. European Guidelines on perioperative venous thromboembolism prophylaxis: Executive summary. Eur J Anaesthesiol. 2018;35(2):77-83. doi:10.1097/EJA.0000000000000729

10.       Aissaoui N, Martins E, Mouly S, Weber S, Meune C. A meta-analysis of bed rest versus early ambulation in the management of pulmonary embolism, deep vein thrombosis, or both. Int J Cardiol. 2009;137(1):37-41. doi:10.1016/j.ijcard.2008.06.020

11.       Kahn SR, Shrier I, Kearon C. Physical activity in patients with deep venous thrombosis: a systematic review. Thromb Res. 2008;122(6):763-773. doi:10.1016/j.thromres.2007.10.011

12.       Nakao S, Takata S, Uemura H, et al. Early ambulation after total knee arthroplasty prevents patients with osteoarthritis and rheumatoid arthritis from developing postoperative higher levels of D-dimer. J Med Investig JMI. 2010;57(1-2):146-151. doi:10.2152/jmi.57.146

13.       Wainwright TW, Burgess L. Early Ambulation and Physiotherapy After Surgery. In: Ljungqvist O, Francis NK, Urman RD, eds. Enhanced Recovery After Surgery: A Complete Guide to Optimizing Outcomes. Springer International Publishing; 2020:211-218. doi:10.1007/978-3-030-33443-7_23

14.       Chua MJ, Hart AJ, Mittal R, Harris IA, Xuan W, Naylor JM. Early mobilisation after total hip or knee arthroplasty: A multicentre prospective observational study. PloS One. 2017;12(6):e0179820. doi:10.1371/journal.pone.0179820

15.       Pearse EO, Caldwell BF, Lockwood RJ, Hollard J. Early mobilisation after conventional knee replacement may reduce the risk of postoperative venous thromboembolism. J Bone Joint Surg Br. 2007;89(3):316-322. doi:10.1302/0301-620X.89B3.18196

16.       Husted H, Otte KS, Kristensen BB, Ørsnes T, Wong C, Kehlet H. Low risk of thromboembolic complications after fast-track hip and knee arthroplasty. Acta Orthop. 2010;81(5):599-605. doi:10.3109/17453674.2010.525196

17.       Chandrasekaran S, Ariaretnam SK, Tsung J, Dickison D. Early mobilization after total knee replacement reduces the incidence of deep venous thrombosis. ANZ J Surg. 2009;79(7-8):526-529. doi:10.1111/j.1445-2197.2009.04982.x

18.       Lei Y-T, Xie J-W, Huang Q, Huang W, Pei F-X. Benefits of early ambulation within 24 h after total knee arthroplasty: a multicenter retrospective cohort study in China. Mil Med Res. 2021;8(1):17. doi:10.1186/s40779-021-00310-x

19.       Cassidy MR, Rosenkranz P, McAneny D. Reducing postoperative venous thromboembolism complications with a standardized risk-stratified prophylaxis protocol and mobilization program. J Am Coll Surg. 2014;218(6):1095-1104. doi:10.1016/j.jamcollsurg.2013.12.061

20.       Aufwerber S, Heijne A, Edman G, Grävare Silbernagel K, Ackermann PW. Early mobilization does not reduce the risk of deep venous thrombosis after Achilles tendon rupture: a randomized controlled trial. Knee Surg Sports Traumatol Arthrosc Off J ESSKA. 2020;28(1):312-319. doi:10.1007/s00167-019-05767-x

21.       Guerra ML, Singh PJ, Taylor NF. Early mobilization of patients who have had a hip or knee joint replacement reduces length of stay in hospital: a systematic review. Clin Rehabil. 2015;29(9):844-854. doi:10.1177/0269215514558641