7/28/2019 Joint 7

1/5

ORTHOPEDICS | ORTHOSuperSite.com

Feature Article

abstract

Full article available online at OrthoSuperSite.com/view.aspx?rID=67563

Effect of Preoperative Exercise onPostoperative Mobility in Obese Total JointReplacement PatientsCLAIRE E. ROBBINS, PT, DPT, MS; JAMES V. BONO, MD; DANIEL M. WARD, MD; MARILYN T. BARRY, PT;

JANICE DOREN, PT; AMANDA MCNINCH, PT, MS

Drs Robbins, Bono, and Ward are from the Department of Orthopedic Surgery, New England Baptist

Hospital, Tufts University School of Medicine, and Dr Robbins and Mss Barry, Doren, and McNinch are

from the Department of Rehabilitation Services, New England Baptist Hospital, Boston, Massachusetts.

Drs Robbins, Bono, and Ward and Mss Barry, Doren, and McNinch have no relevant financial rela-

tionships to disclose.

Correspondence should be addressed to: Claire E. Robbins, PT, DPT, MS, Department of Ortho-

pedic Surgery, New England Baptist Hospital, 125 Parker Hill Ave, Boston, MA 02120 (crobbins@

caregroup.harvard.edu).

doi: 10.3928/01477447-20100722-09

There has been a significant increase in obesity in the United States over the past 20

years. Reports in the literature identify the association of obesity-related osteoarthritis

and the likelihood of future total hip arthroplasty (THA) and total knee arthroplasty

(TKA) in this patient population. However, little is known about the effect of preopera-

tive exercise on immediate postoperative mobility and discharge disposition in obese

total joint replacement patients. The purpose of this study was to examine the effect of

preoperative exercise in the obese total joint replacement patient on early postopera-

tive mobility and discharge disposition.

We retrospectively reviewed a consecutive series of patients with a body mass index

(BMI) 30 kg/m2 who underwent primary total joint replacement surgery from June

2005 through October 2005 at 1 institution. Two hundred seven patients met the in-

clusion criteria. Sixty-five patients performed self-reported preoperative exercise, de-

fined as physical activity deemed above and beyond that of activities of daily living.Fewer exercise patients, 6.8%, required the assistance of2 caregivers for mobility on

postoperative day 1 vs 17.4% for nonexercisers. Fifty-four percent of patients partici-

pating in preoperative exercise were discharged home vs 46% who did not participate

in exercise. A preoperative exercise program can improve postoperative functional

mobility and increase the likelihood of discharge home in total joint replacement pa-

tients with a BMI of30 kg/m2.

7/28/2019 Joint 7

2/5

SEPTEMBER 2010| Volume 33 Number 9

POSTOPERATIVE MOBILITYIN OBESE TOTAL JOINT REPLACEMENT PATIENTS | ROBBINSETAL

There has been a significant in-

crease in obesity in the United

States over the past 20 years. In

2008, only 1 state, Colorado, had an obe-

sity rate 20%.1 The National Institutes

of Health (NIH) guidelines define obesity

as a body mass index (BMI) of30 kg/

m2 and morbid obesity as a BMI of40

kg/m2.2 Body mass index is calculated by

dividing the patients weight in kilograms

by the square of the patients height in

meters. Obesity is a health condition as-

sociated with an increased incidence of

multiple medical comorbidities, includ-

ing osteoarthritis. Reports in the literature

identify the association of obesity-related

osteoarthritis and the likelihood of future

total hip arthroplasty (THA) and total

knee arthroplasty (TKA) in this patient

population.3-9

The anticipated benefits of reducing

pain and improving function following

joint replacement surgery should not over-

shadow discussion of potential periopera-

tive and postoperative risks. Obese and

morbidly obese patients pose challenges

not only for the surgical team, but for the

postoperative medical, nursing, and reha-

bilitation staff.10,11 Preoperative knowl-

edge of the risks and benefits may prove

invaluable to both surgeon and patient.

In 2006, Rooks et al12 reported on the

effect of preoperative exercise on function-al measures in men and women undergo-

ing THA and TKA. Several authors report

on hospital length of stay and discharge

disposition in the obese patient popula-

tion.5,7,10,13,14 However, less is known about

the effect of preoperative exercise on imme-

diate postoperative mobility and discharge

disposition in obese total joint replacement

patients. We hypothesize a decrease in as-

sistance with postoperative mobility and an

increase in patients discharged home with

obese THA and TKA patients participating

in a preoperative exercise program.

MATERIALSANDMETHODSAfter institutional review board ap-

proval, we retrospectively reviewed a con-

secutive series of patients with a BMI of

30 kg/m2 who underwent primary THA

or TKA between June 2005 and October

2005. These patients were selected from

the hospital database. During this period,

several orthopedic surgeons performed

300 THAs and TKAs on this patient co-

hort. Two hundred seven patients met the

inclusion and exclusion criteria. Seventy-

six patients received primary THAs and

131 patients received primary TKAs using

a traditional, noncomputer-assisted surgi-

cal approach. All surgeries were elective

procedures.

Fifty-eight percent of the patients

(120) were women and 42% (87) were

men. Mean patient age at the time of sur-

gery was 63.1 years (range, 31-87 years).

The principal diagnosis was osteoarthritis.

One hundred patients had a BMI of30

kg/m2 and 107 patients had a BMI of40

kg/m2.

The inclusion criteria for patients

participating in a preoperative exercise

program included adult men and women

between the ages of 30 and 90 years and

an underlying diagnosis of osteoarthritis,

rheumatoid arthritis, or traumatic arthritis

that required a primary THA or TKA. The

patients had a documented BMI of30

kg/m2 during the preoperative screening

process.

The inclusion criteria for the compari-son group (patients who did not partici-

pate in a preoperative exercise program)

were the same. Exclusion criteria includ-

ed use of the minimally invasive capsular

preserving surgical approach with THA, a

computer-assisted procedure, and having

bilateral joint replacement surgeries per-

formed on the same day.

Patients deemed eligible following

retrospective review of the medical re-

cords were consecutively assigned to

either the preoperative exercise group or

the group that did not partake in a pre-

operative exercise program. For purposes

of this study, preoperative exercise was

defined during the preoperative screen-

ing process as participation in physical

activity deemed above and beyond that of

the activities of daily living. There were

no eligibility guidelines with respect to

type of activity or intensity. Therefore,

self-reported, preoperative exercise or

activity programs varied in both type

and level of participation. Preoperative,

self-reported physical activities included,

but were not limited to, biking, stretch-

ing, walking, swimming, water aerobics,

low-impact aerobics, going to a health

club, and participating in formalized out-

patient physical therapy.

Postoperative surgical and rehabili-

tation protocols for primary THA and

TKA were similar among the arthroplasty

surgeons. Patients were allowed to bear

weight as tolerated with an assistive de-

vice. Two surgeons allowed only partial

weight bearing during the immediate

postoperative period. The majority of

THA patients observed posterior THA

precautions, and active-assisted thera-

peutic exercises were initiated on the first

postoperative day. At the time, there were

slight differences with perioperative pain

regimes among the surgeons, and 1 sur-

geon deferred continuous passive motion

machine application until the first postop-

erative day with TKA patients.

Functional mobility is defined to in-

clude bed mobility, supine-to-sit transfers,

and sit-to-stand transfers. A data collec-tion sheet developed by the authors was

used to extract information from the medi-

cal record during the retrospective review.

The data collection sheet contained fields

for demographic information, BMI, date

of surgery, type of surgery/surgeon, dis-

charge disposition, and amount of assist

for functional mobility. The amount of as-

sist for functional mobility was recorded

on the first postoperative day in which

the patient was mobilized with physical

therapy.

The McNemar test, typically used to

test 2 study proportions obtained from the

same group of respondents, was used to

evaluate postoperative functional mobil-

ity between the exercise and nonexercise

7/28/2019 Joint 7

3/5

ORTHOPEDICS | ORTHOSuperSite.com

Feature Article

group.15 The z-test for 2 proportions was

used to compare discharge disposition.16

RESULTSObese and morbidly obese patients of-

ten require more staff assistance with post-

operative mobility after joint replacement

surgery.5,10 Fewer preoperative exercise pa-

tients, 6.8%, required the assistance of2

caregivers for functional mobility on post-

operative day 1 vs 17.4% for nonexercis-

ers. This result was statistically significant

(P.0261) with a 2-tailed confidence level

of 99.8%. Tables 1 and 2 show the progres-

sion of patients through postoperative day

4 who required the assistance of2 care-

givers. The postoperative protocol variance

among surgeons did not affect the level of

functional mobility between the 2 groups.

Discharge disposition, home vs re-

habilitation facility, was assessed. Fifty-

four percent of patients participating in

preoperative exercise were discharged

home vs 46% who did not participate in

exercise. Z-test calculations showed the

difference was not statistically significant

(P.3524).

Of patients requiring the assistance of

1 person for postoperative functional

mobility, only 3 were discharged home.

Home discharge in this cohort included

2 exercise patients receiving THAs and

1 nonexercise patient receiving a THA.No patients requiring increased assistance

with mobility who underwent TKA sur-

gery were discharged to home. No patients

with a BMI 40 kg/m2 who required the

assistance of2 caregivers for functional

mobility were discharged home.

DISCUSSIONIn November 2007, the American Med-

ical Association, in collaboration with the

American College of Sports Medicine,

introduced the Exercise Is Medicine ini-

tiative.17 Together, the 2 groups called on

all physicians, regardless of specialty, to

educate their patients on the importance

of incorporating physical activity into

their daily routines. The American Acad-

emy of Orthopaedic Surgeons shares in

this initiative and posts a position state-

ment on their website, The Need for Daily

Physical Activity, which may be used by

both patients and health care providers as

an educational tool when considering an

exercise program.18 We consider the Ex-

ercise Is Medicine initiative as a valuable

preoperative component for all patients

considering joint replacement surgery.

We conducted a retrospective study to

examine the effect of self-reported pre-

operative exercise in the obese total joint

replacement patient. We looked at the im-

pact of preoperative exercise interventionon early postoperative functional mobility

and discharge disposition. To our knowl-

edge, this is one of the few studies to ex-

amine the potential benefits of preopera-

tive exercise on obese and morbidly obese

patients undergoing primary total joint

replacement surgery.3,12

It was found that fewer patients who

performed a self-reported exercise routine

prior to joint replacement surgery required

the assistance of2 caregivers for imme-

diate postoperative functional mobility. A

caveat to consider when interpreting this

finding is that self-reported, preoperative

exercise programs varied in both type

and level of participation amongst obese

total joint replacement patients. All pa-

tients were provided the opportunity to

report participation in preoperative exer-

cise to a health care provider during the

preadmission screening process, and the

self-reported information was recorded as

part of the medical record. However, some

patients may have failed to consider their

daily walk or stretching as exercise and

therefore did not report it. A retrospective

review of the medical record would then

indicate the patient was a nonexerciser.

No patients in the nonexercise group were

contacted for clarification of preoperative

exercise participation.

Although more patients in the exercisegroup were discharged home compared

to the nonexercise group, we cannot at-

tribute this purely to preoperative exercise

intervention.19-21 The nonrandomized, ret-

rospective design did not control for age,

comorbidities, socioeconomic status, pre-

operative education, or patient expecta-

tions and motivation.

We recognize the limitation of a retro-

spective study design. However, we be-

lieve the study provides valuable insight

into the positive postoperative effects of

preoperative exercise in a select group of

obese total joint replacement patients. A

prospective, randomized controlled de-

sign may have improved the clinical sig-

nificance of our findings.

Table 1

TKA Patients Requiring the

Assistance of

1 CaregiverWith Postoperative

Functional Mobility

BMI 30 kg/m2

WithExercise

WithoutExercise

Day 1 8 22

Day 2 5 18

Day 3 4 10

Day 4 2 6

Abbreviations: BMI, body mass index;TKA, total knee arthroplasty.

Table 2

THA Patients Requiring the

Assistance of

1 CaregiverWith Postoperative

Functional Mobility

BMI 30 kg/m2

WithExercise

WithoutExercise

Day 1 6 14

Day 2 6 9

Day 3 2 7

Day 4 2 3

Abbreviations: BMI, body mass index;THA, total hip arthroplasty.

7/28/2019 Joint 7

4/5

SEPTEMBER 2010| Volume 33 Number 9

POSTOPERATIVE MOBILITYIN OBESE TOTAL JOINT REPLACEMENT PATIENTS | ROBBINSETAL

CONCLUSIONA self-reported preoperative exercise

program can improve postoperative func-

tional mobility and increase the likelihood

of discharge to home in total joint replace-

ment patients with a BMI30 kg/m2. Our

results support the feasibility of a larger,

prospective study to examine the effect of

formalized preoperative exercise on pa-

tients with a BMI 30 kg/m2 vs patients

with a BMI 30 kg/m2 anticipating total

joint replacement surgery.

REFERENCES1. Obesity and Overweight for Professionals:

Data and Statistics: US Obesity Trends. Cen-ters for Disease Control and Prevention Website. http://www.cdc.gov/obesity/data/trends.html. Accessed November 12, 2009.

2. Clinical Guidelines on the Identification,Evaluation, and Treatment of Over-Weightand Obesity in Adults: The Evidence Report,1998. National Institutes of Health Web site.http://nhlbi.nih.gov/guidelines/obesity/ob_gdlns.pdf. Accessed November 12, 2009.

3. Busato A, Rder C, Herren S, Eggli S. In-fluence of high BMI on functional outcomeafter total hip arthroplasty. Obes Surg. 2008;18(5):595-600.

4. Karlson EW, Mandl LA, Aweh GN, SanghaO, Liang MH, Grodstein F. Total hip replace-ment due to osteoarthritis: the importance ofage, obesity, and other modifiable risk fac-tors.Am J Med. 2003; 114(2):93-98.

5. Vincent HK, Weng JP, Vincent KR. Effect ofobesity on inpatient rehabilitation outcomesafter total hip arthroplasty. Obesity (SilverSpring). 2007; 15(2):522-530.

6. Gillespie GN, Porteous AJ. Obesity and kneearthroplasty. Knee. 2007; 14(2):81-86.

7. Fehring TK, Odum SM, Griffin WL, MasonJB, McCoy TH. The obesity epidemic: its ef-fect on total joint arthroplasty.J Arthroplasty.2007; 22(6 suppl 2):71-76.

8. Crowninshield RD, Rosenberg AG, SporerSM. Changing demographics of patients withtotal joint replacement. Clin Orthop Relat

Res. 2006; (443):266-272.

9. Iorio R, Robb WJ, Healy WL, et al. Ortho-paedic surgeon workforce and volume assess-ment for total hip and knee replacement in theUnited States: preparing for an epidemic. J

Bone Joint Surg Am. 2008; 90(7):1598-1605.

10. McDonald JE, Huo MH. Total hip replace-ment: unique challenges in the obese and ge-riatric populations. Curr Opin Orthop. 2008;19(2):33-36.

11. Gallagher S. Caring for the overweight pa-tient in the acute care setting: addressingcaregiver injury.Journal of Healthcare, Safe-ty, Compliance, and Infection Control. 2000;4(8):379-382.

12. Rooks DS, Huang J, Bierbaum BE, et al. Ef-fect of preoperative exercise on measures offunctional status in men and women under-going total hip and knee arthroplasty.Arthri-tis Rheum. 2006; 55(5):700-708.

13. Barsoum WK, Murray TG, Klika AK, et al.Predicting patient discharge disposition aftertotal joint arthroplasty in the United States.J

Arthroplasty. In press.

14. Munin MC, Rudy TE, Glynn NW, CrossettLS, Rubash HE. Early inpatient rehabilita-tion after elective hip and knee arthroplasty.

JAMA. 1998; 279(11):847-852.

15. McNemar test calculator. Dimension Re-search, Inc, Web site. http://www.dimension-research.com/resources/calculators/mcne-mar.html. Accessed November 25, 2009.

16. Z-test for two proportions calculator. Dimen-sion Research, Inc, Web site. http://www.di-mensionresearch.com/resources/calculators/ztest.html. Accessed November 25, 2009.

17. Davis RM. Exercise: a dose of medicine wecan all use. American Medical AssociationWeb site. http://www.ama-assn.org/ama/no-index/news/18118.shtml. Published Novem-ber 8, 2007. Accessed November 25, 2009.

18. Position statement: the need for daily physi-cal activity. American Academy of Orthopae-dic Surgeons Web site. http://www.aaos.org/about/papers/position/1138.asp. PublishedFebruary 1997. Updated December 2008.Accessed November 25, 2009.

19. Oldmeadow LB, McBurney H, RobertsonVJ, Kimmel L, Elliott B. Targeted postopera-tive care improves discharge outcome afterhip or knee arthroplasty.Arch Phys Med Re-habil. 2004; 85(9):1424-1427.

20. de Pablo P, Losina E, Phillips CB, et al. De-terminants of discharge destination follow-ing elective total hip replacement. Arthritis

Rheum. 2004; 51(6):1009-1017.

21. Bozic KJ, Wagie A, Naessens JM, Berry DJ,Rubash HE. Predictors of discharge to an in-patient extended care facility after total hip orknee arthroplasty.J Arthroplasty. 2006, 21(6Suppl 2):151-156.

7/28/2019 Joint 7

5/5

Copyright of Orthopedics is the property of SLACK Incorporated and its content may not be copied or emailed

to multiple sites or posted to a listserv without the copyright holder's express written permission. However,

users may print, download, or email articles for individual use.