Vol.2, No.2, 157-161 (2010)
doi:10.4236/health.2010.22023
SciRes Copyright © 2010 Openly accessible at http://www.scirp.org/journal/HEALTH/
Health
Is overweight or obesity a perioperative risk factor in
total hip replacement?
Mushtaq AlAssaf1, Michael Kolbeck2, Wolfgang Hönle1, Alexander Schuh2
1Department of Orthopaedic Surgery, Neumarkt Clinic, Neumarkt, Germany
2Research Unit Orthopaedics and General Surgery, Neumarkt Clinic, Neumarkt,Germany;
Received 20 October 2009; revised 31 December 2009; accepted 3 January 2010.
ABSTRACT
Introduction: A large proportion of patients who
undergo total hip replacement (THR) are obese.
Aim of the present study is to investigate the
influence of Body Mass Index (BMI) on compli-
cations following THR in a single surgeon in the
short term follow-up. Material and method: This
study was based on the retrospective review of
charts and BMIs from 171 patients who had
undergone THR between April 2005 and March
2006 at our hospital. All operations were per-
formed by a single surgeon. All patients were
followed up 6 weeks after operation. Results: 27
/ 171 patients (15.8%) were found to have com-
plications. Systemic minor complications in-
cluded arrythmia in 1 case, urinary tract infec-
tion in two cases, ileus in two cases, renal in-
sufficiency in 3 cases, confusion in 2 cases and
anaemia in 14 cases (8.2%) requiring blood tr-
ansfusion. There was one case of pulmonary
embolism as a major systemic complication.
Local minor complications included one single
dislocation and 1 superficial wound infection.
Body mass index ranged from 20.8 to 46.7 with a
mean of 28.6. Hospital length of stay ranged
from 10 to 42 days with a mean of 13. The leng-
th of operation time between obese and non-
obese patients varied significantly in our study.
There was no increased risk for complications
and length of hospital stay. Discussion: We can
conclude that there are no economic or medical
reasons for excluding obese patients from THR
as there is no increased risk for complications
and length of hospital stay.
Keywords: Total Hip Replacement, Complication,
Obesity, BMI, Bleeding
1. INTRODUCTION
A large proportion of patients who undergo total hip re-
placement (THR) are obese 17,18. There has been mu-
ch concern that obesity is associated with anaesthetic
and operative complications after THR. Obese patients
have a higher risk of adverse cardiovascular and respi-
ratory events and obesity is an independent risk factor
for the development of type II diabetes mellitus, a condi-
tion that carries an increased risk of post-operative mor-
bidity. Other studies have demonstrated an increased risk
of venous thromboembolic disease following joint re-
placement surgery in the obese. There is a strong asso-
ciation between obesity and prolonged wound drainage
post-operatively which, in turn, is associated with a
higher rate of wound infection and blood loss 1,4,20.
Namba et al. 15 concluded that obese patients have a
4.2 times higher risk of post-operative infection follow-
ing THR. Furthermore, obesity has a bearing on health
economics, with obese patients having an increased
length of hospital stay compared with the general popu-
lation 3,12. Recently a weak correlation BMI and the
complication rate in THR has been published by Patel A
et al. 17. He stated that orthopaedic surgeons should be
aware of the slightly higher risk in THR in such patients.
On the other hand several authors found no increased
post-operative complications rate in obese patients un-
dergoing THR 2,9,11,19. Aim of this study was to in-
vestigate the influence of BMI on complications follow-
ing THR in a single surgeon.
2. MATERIAL AND METHOD
This study was based on the retrospective review of
charts and BMIs from 171 patients who had undergone
THR between April 2005 and March 2006 at our hospi-
tal. All operations were performed by a single surgeon
(WH). Prior to surgery weight and height of the patients
were recorded by nursing staff. BMI was calculated as
the body weight in kilograms divided by the height in
metres squared. Co-morbid conditions were also re-
corded. Any complications reported by the patient or the
medical staff were recorded. Complications were group-

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ed into systemic and local, each group being subdivided
into minor and major according to Patel 17. A compli-
cation that could be treated with medical and conserva-
tive management or that was not a risk to the artificial
joint and/or the patient was listed as a minor complica-
tion (superficial infection, ooze, pain). Any complication
that needed surgical/medical intervention and posed a
risk to the joint or the patient was listed as a major com-
plication (dehiscence, deep infection, post- operative
stiffness requiring manipulation under anaesthesia,
haematoma requiring second operation, cardiac arrest,
deep vein thrombosis, cardiovascular accident, conges-
tive cardiac failure, systemic infection, intensive care
unit admission, myocardial infarction, pulmonary embo-
lism). There were 75 men and 96 women. Average
height was 168 cm (Min: 147, Max: 193). Average
weight was 81 Kg (Min: 53, Max: 160). Average age at
time of operation was 66 years (Min: 43, Max: 90). We
reviewed all BMIs and divided the patients into 4 groups:
BMI < 26 (Optimal and under weight), 26 - 30 (Clini-
cally overweight), 31 - 40 (Clinically obese), > 40
(Morbidly obese) 4. Patient clinical complexity level
(PCCL) was assigned. PCCL of women was 0 in 62
cases, 1 in 1 case, 2 in 14 cases, 3 in 12 cases and 4 in 7
cases. PCCL of men was 0 in 55 cases, 2 in 7 cases, 3 in
10 cases and 4 in 3 cases. The indications for THR were
dysplastic coxarthrosis (15), primary arthrosis of the hip
(124), inflammatory arthritis (2), secondary osteoarthri-
tis (26), rheumatoid arthritis (3), necrosis of the femoral
head (1).
On the acetabular side, a standard cementless acetabu-
lar cup according to Wagner was used in 148 cases, in 19
cases a cemented full-profile polyethylene cup in 4 cases
an acetabular reconstruction ring. On the femoral side, 1
case was treated with the cementless Cone Prosthesis
according to Wagner, 154 with a cementless CLS stem
and 16 with a cemented Müller Straight Stem. The bear-
ing surfaces were polyethylene/ceramic in all cases. All
procedures were performed in an ultra-clean-air theater
(with antibiotic prophylaxis). During their stay at the
hospital, all patients were treated with low molecular
weight Heparin and compression stockings as a prophy-
laxis against deep vein thrombosis. For the duration of 8
weeks, partial weight bearing of 20 kg with the support
of lower arm crutches was required. Average operation
time was 65 min (Min: 42, Max: 170).
Data were first fed in electronic format into Excel.
Accuracy of the electronic data was confirmed by three
independent observers. Data were then analysed for fre-
quencies and Chi-squared test. All patients were fol-
lowed up by one of us (MA) 6 weeks after operation.
3. RESULTS
Body mass index ranged from 20.8 to 46.7 with a mean
of 28.6. 27 / 171 patients (15.8%) were found to have
complications. Systemic minor complications included
arrythmia in 1 case, acute hypertension in one case, uri-
nary tract infection in two cases, ileus in two cases, renal
insufficiency in 3 cases, confusion in 2 cases and anae-
mia in 14 cases (8.2%) requiring blood transfusion.
There was one case of pulmonary embolism as a major
systemic complication. Local minor complications in-
cluded one single dislocation and 1 superficial wound
infection. Hospital length of stay ranged from 10 to 42
days with a mean of 13. Average loss of haemoglobin in
women was -3.5 (Min: -0.8, Max: -9.2) and in men -3.8
(Min: -1, Max: -7.7) (Table 1). Table 2 shows the dif-
ferent complications and related BMI.
For the purpose of analysis patients were split into 4
groups of BMI (Table 3) with a complication rate rang-
ing from 6.2 - 41.5% (17/ 41 (41.5%), 4/64 (6.2%), 5/ 62
(8.0%) and 2/6 (33.3%). When patients were put into
BMI groups there was no effect on complication rate
with increasing BMI.
Table 1. Distibution of demographic data and BMI.
BMI vs Hemoglobin loss Mean (g/dl)
Women
< 26 -3,84
26 - 30 -3,88
31 - 40 -3,68
> 40 -3,30
Men
< 26 -4,77
26 - 30 -3,72
31 - 40 -4,11
> 40 ---
BMI vs. Length of hospital stay Mean (days)
Women
< 26 13,5
26 - 30 13,14
31 - 40 13,82
> 40 14,66
Men
< 26 13,5
26 - 30 13,12
31 - 40 15,62
> 40 ---
BMI vs. Duration of operation Mean (hours)
Women
< 26 1:08
26 - 30 1:04
31 - 40 1:07
> 40 1:27
Men
< 26 1:02
26 - 30 1:04
31 - 40 1:09
> 40 ---

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Table 2. Complications and BMI.
Initials Complication Sex Age BMI
BE1 Acute hypertension f 56 42,2
GM1 Acute renal failure f 80 20,8
NR1 Acute renal failure m 62 32,0
TG1 Acute renal failure f 73 30,1
KF1 Postoperative Delirium m 79 23,4
RM1 Postoperative Delirium f 90 21,2
KF1 Arrhythmia m 79 23,4
AE1 Haemorrhage f 81 25,8
AC1 Haemorrhage f 66 24,7
GH1 Haemorrhage f 70 22,6
GM1 Haemorrhage f 80 20,8
KH1 Haemorrhage f 77 25,2
KM1 Haemorrhage f 46 23,7
NR1 Haemorrhage m 62 32,1
PM1 Haemorrhage f 55 26,4
RA1 Haemorrhage f 59 23,4
SB1 Haemorrhage f 81 25,6
SH1 Haemorrhage m 76 28,7
TG1 Haemorrhage f 73 30,1
WC1 Haemorrhage f 90 24,5
WM1 Haemorrhage f 82 21,3
KP1 Ileus, not particularly specified m 68 34,3
SA1 Ileus, not particularly specified m 75 30,3
GM1 Infection, not particularly specified f 80 20,8
EG1 Dislocation m 56 35,9
BE1 Pulmonary embolism f 56 42,2
BR1 Urinary tract infection f 78 25,0
KF1 Urinary tract infection m 79 23,4
Table 3. Correlation between complications and BMI divided
into four groups.
Complications BMI groups
No Yes
< 26 Count 24 17
26 - 30 Count 60 4
31 - 40 Count 57 5
> 40 Count 4 2
4. DISCUSSION
The numbers of patients presenting for THR who are
obese is increasing and there have been concerns that
these patients have an increased risk of complications
and a reduced benefit of surgery in terms of function and
pain relief 3,9,13,14,16. A higher risk for obese pa-
tients in respect to deep infection dislocations and revi-
sion rate for septic loosening has been postulated 7,8,
10,12,21.
Stickles et al. 23 reported a higher rate of orthopae-
dic complications (infection, dislocation, component
failure) with increasing BMI in the first year after THR.
Obese patients are often considered poor candidates
for total joint arthroplasty. These patients tend to have
longer hospital stays and higher total charges compared
with nonobese patients 6. Ibrahim et al. 9 could not
found any difference in the length of hospital stay be-
tween obese and non-obese patients. This compares fa-
vourably with our results. Within the current literature,
the effect of obesity on THA remains varied. Some re-
ports have found no difference in the rate of periopera-
tive complications between obese and non-obese patients.
Anderson et al. 2 and Soballe et al. 22 found no rela-
tionship between obesity and postoperative complica-
tions. Lehman et al. 11 showed no difference in the
prevalence of perioperative complications in obese pa-

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tients with similar gains in pain relief and functional
abilities as non-obese patients. Chan and Villar 5
showed no difference in the quality of life in the short
term following THA between obese and non-obese pa-
tients. With our study results we can follow Andrew et al.
3 and Ibrahim et al. 9 that there is no association be-
tween obesity and the risk of revision surgery or other
complications. Especially we could not found any in-
creased risk for hematoma, dislocation rate and infection
rate and the rate of blood transfusion in the short term
follow up.
Certainly a limitation of this study is the short period
of follow-up. This limitation is of particular importance
to the rate of revision surgery. A major advantage of our
study is a consecutive patient series who were operated
by the same orthopaedic surgeon. Patel et al. 17 came
to the same conclusion in a patient cohort who was op-
erated by seven different orthopaedic surgeons. Interest-
ingly Bowditch et al. 4 found a higher rate of blood
loss in obese patients. A lack of this study is the small
number of 80 Patients operated by four surgeons. To be
able to compare different studies we suggest a larger
series of patients operated by the same orthopaedic sur-
geon and the use of the same classification system for
obesity. We believe that the lack of consensus regarding
the impact of obesity on THR may be explained in part
by the different definitions of obesity which have been
used 3. The aim of our study was to investigate the
influence of BMI on early complications in THR. The
length of operation between obese and non-obese pa-
tients varied significantly in our study. Nevertheless we
can conclude that there are no economic or medical rea-
sons for excluding obese patients from THR, especially
as there is no increased risk for complications and length
of hospital stay. We fully agree with Andrew et al. 3
who postulated that patients should still be encouraged
to reduce their weight prior to surgery but it seems un-
acceptable for patients to be denied treatment in the form
of hip replacement solely on the basis of their BMI.
REFERENCES
[1] Aderinto, J. and Brenkel, I.J. (2004) Pre-operative pre-
dictors of the requirement for blood transfusion follow-
ing total hip replacement. J Bone Joint Surg Br, 86-Br,
970–3.
[2] Anderson, L., Kammerer, W.S. and Greer, R.B. III (1979)
Risk factor assessment in 101 total hip arthroplasties.
Clin Orthop, 141, 50–54.
[3] Andrew, J.G., Palan, J., Kurup, H.V., Gibson, P., Murray,
D.W. and Beard, D.J. (2008) Obesity in total hip re-
placement. J Bone Joint Surg Br, 90-Br, 424–9.
[4] Bowditch, M.G. and Villar, R.N. (1999) Do obese pa-
tients bleed more? A prospective study of blood loss at
total hip replacement. Ann R Coll Surg Engl, 81, 198
–200.
[5] Chan, C.L.H. and Villar, R.N. (1996) Obesity and quality
of life after primary hip arthroplasty. J Bone Jt Surg Br,
78-Br, 78–81.
[6] Epstein, A.M., Read, L. and Hoefer, M. (1987) The rela-
tion of body weight to length of stay and charges for
hospital services for patients undergoing elective surgery:
a study of two procedures. Am J Public Health, 77, 993–
997.
[7] Giurea, A, Zehetgruber, H., Funovics, P., Grampp, S.,
Karamat, L. and Gottsauner-Wolf, F. (2001) Risk factors
for dislocation of a cementless total hip endoprosthe-
sis—a statistical analysis. Z Orthop Ihre Grenzgeb, 139,
194–9.
[8] Haverkamp, D., de Man, F.H., de Jong, P.T., van Stralen,
R.A. and Marti, R.K. (2008) Is the long-term outcome of
cemented THA jeopardized by patients being overweight?
Clin Orthop Relat Res, 466, 1162–8.
[9] Ibrahim, T., Hobson, S., Beiri, A. and Esler, C.N. (2005)
No influence of body mass index on early outcome fol-
lowing total hip arthroplasty. Int Orthop., 29, 359–61.
[10] Jibodh, S.R., Gurkan, I. and Wenz, J.F. (2004) In-hospital
outcome and resource use in hip arthroplasty: influence
of body mass. Orthopedics, 27, 594–601.
[11] Lehman, D.E., Capello, W.N., Feinberg, J.R. (1994) Total
hip arthroplasty without cement in obese patients. A
minimum two year clinical and radiographic follow-up
study. J Bone Jt Surg Am, 76-Am, 854–862.
[12] Lübbeke, A., Stern, R., Garavaglia, G., Zurcher, L. and
Hoffmeyer, P. (2007) Differences in outcomes of obese
women and men undergoing primary total hip arthro-
plasty. Arthritis Rheum., 57, 327–34.
[13] Marker, D.R., Seyler, T.M., Jinnah, R.H., Delanois, R.E.,
Ulrich, S.D. and Mont, M.A. (2007) Femoral neck frac-
tures after metal-on-metal total hip resurfacing: a pro-
spective cohort study. J Arthroplasty, 22(7 Suppl 3), 66
–71.
[14] Moran, M., Walmsley, P., Gray, A. and Brenkel, I.J.
(2005) Does body mass index affect the early outcome of
primary total hip arthroplasty? J Arthroplasty, 20, 866–9.
[15] Namba, R.S., Paxton, L., Fithian, D.C. and Stone, M.L.
(2005) Obesity and perioperative morbidity in total hip
and total knee arthroplasty patients. J Arthroplasty, 20,
46–50.
[16] Parvizi, J., Mui, A., Purtill, J.J., Sharkey, P.F., Hozack,
W.J. and Rothman, R.H. (2007) Total joint arthroplasty:
When do fatal or near-fatal complications occur? J Bone
Joint Surg Am, 89-Am, 27–32.
[17] Patel, A.D. and Albrizio, M. (2007) Relationship of body
mass index to early complications in hip replacement
surgery : study performed at Hinchingbrooke Hospital,
Orthopaedic Directorate, Huntingdon, Cambridgeshire.
Int Orthop., 31, 439–43.
[18] Patel, V.P., Walsh, M., Sehgal, B., Preston, C., DeWal, H.,
Di Cesare, P.E. (2007) Factors associated with prolonged
wound drainage after primary total hip and knee arthro-
plasty. J Bone Joint Surg Am, 89-Am, 33–8.
[19] Perka, C., Labs, K., Muschik, M. and Buttgereit, F. (2000)
The influence of obesity on perioperative morbidity and
mortality in revision total hip arthroplasty. Arch Orthop
Trauma Surg., 120, 267–271.
[20] Pola, E., Papaleo, P., Santoliquido, A., Gasparini, G.,
Aulisa, L. and De Santis, E. (2004) Clinical factors asso-

M. AlAssaf et al. / HEALTH 2 (2010) 157-161
SciRes Copyright © 2010 http://www.scirp.org/journal/HEALTH/Openly accessible at
161
ciated with an increased risk of perioperative blood
transfusion in nonanemic patients undergoing total hip
arthroplasty. J Bone Joint Surg Am., 86-Am, 57–61.
[21] Sadr Azodi, O., Adami, J., Lindström, D., Eriksson, K.O.,
Wladis, A. and Bellocco, R. (2008) High body mass in-
dex is associated with increased risk of implant disloca-
tion following primary total hip replacement: 2,106 pa-
tients followed for up to 8 years. Acta Orthop., 79, 41–7.
[22] Soballe, K., Christensen, F. and Luxhoj, T. (1987) Hip
replacements in obese patients. Acta Orthop Scand., 58,
223–225.
[23] Stickles, B., Phillips, L., Brox, W.T., Owens, B. and
Lanzer, W.L. (2001) Defining the relationship between
obesity and total joint arthroplasty. Obes Res., 9, 219–23.