INCIDENCE OF INFECTION AND ASSOCIATED FACTORS
AFTER PRIMARY TOTAL KNEE REPLACEMENT
CALEB KARUGA NYAGAH
H58/11862/2018
A RESEARCH PROPOSAL SUBMITTED IN PARTIAL FULFILMENT FOR
THE AWARD OF MASTER OF ORTHOPAEDICS AND TRAUMA SURGERY,
UNIVERSITY OF NAIROBI.
JULY, 2022
DECLARATION
This research proposal is my original work and has not been presented in this university
or any other institution of higher learning in the award of a degree.
Dr. Caleb Karuga Nyagah
M.Med Resident, Department of Surgery, Orthopaedics and Trauma Unit
University of Nairobi.
Registration Number H58/11862/2018
Signed…………………… Date…………………………………
i
APPROVAL BY SUPERVISORS
This proposal has been submitted with our approval as the university supervisors:
1. DR. EDWARD GAKUYA
Lecturer, Department of Orthopaedics Surgery, University Of Nairobi,
Consultant Orthopaedic Surgeon, Division of Orthopaedics, Kenyatta National Hospital
Signature:.............................. Date:..................................
2. DR FRED SITATI
Lecturer, Department of Orthopaedics Surgery, University Of Nairobi,
Consultant Orthopaedic Surgeon, Division of Orthopaedics, Kenyatta National Hospital
Signature:.............................. Date:..................................
ii
TABLE OF CONTENTS
DECLARATION................................................................................................................ i
SUPERVISORS, APPROVAL ......................................................................................... ii
TABLE OF CONTENTS ................................................................................................. iii
LIST OF ACRONYMS AND ABBREVIATIONS .......................................................... v
ABSTRACT ..................................................................................................................... vi
CHAPTER ONE................................................................................................................ 1
1.0 BACKGROUND ......................................................................................................... 1
CHAPTER TWO ............................................................................................................... 3
2.0 LITERATURE REVIEW ............................................................................................ 3
2.1 Definition of primary total knee replacement, prevalence and indications. ............ 3
2.2 Complications of TKR. ........................................................................................... 4
2.3 Epidemiology of infection after primary TKR. ....................................................... 6
2.4 Risk factors for infection after TKR........................................................................ 7
2.5 Outcomes of infection ............................................................................................. 9
2.6 Gaps in literature in sub-Saharan Africa ............................................................... 10
2.7 Justification. .......................................................................................................... 10
2.8 Research Questions ............................................................................................... 11
2.9 Study Objectives.................................................................................................... 11
2.9.1 Broad objective............................................................................................... 11
2.9.2 Specific objectives .......................................................................................... 11
2.10
Conceptual framework .................................................................................. 12
CHAPTER THREE ......................................................................................................... 13
3.0 METHODOLOGY .................................................................................................... 13
3.1 Study design .......................................................................................................... 13
3.2 Study Site .............................................................................................................. 13
3.3 Study population.................................................................................................... 13
3.4 Inclusion and Exclusion Criteria ........................................................................... 13
3.4.1. Inclusion criteria ............................................................................................ 13
3.4.2 Exclusion Criteria. .......................................................................................... 14
3.5 Sample Size Determination ................................................................................... 14
iii
3.6
Sampling Procedure .......................................................................................... 15
3.7 Variables ................................................................................................................ 15
3.8 Data Collection ...................................................................................................... 15
3.8.1Recruitment and Training procedures ............................................................. 16
3.9 Quality assurance measures................................................................................... 16
3.10 Ethical Considerations ......................................................................................... 16
3.11 Data Management................................................................................................ 17
3.12 Data Analysis ...................................................................................................... 17
3.13 Data dissemination .............................................................................................. 18
3.14 Study Limitations ................................................................................................ 18
DUMMY TABLE ....................................................................................................... 18
STUDY BUDGET .......................................................................................................... 19
STUDY TIME FRAME .................................................................................................. 20
REFERENCES ................................................................................................................ 21
LIST OF APPENDICES ................................................................................................. 24
Appendix 1: Data collection tool................................................................................. 24
Appendix 2: Informed consent – English Version ...................................................... 26
Appendix 3- Consent Form (Statement of Consent)-ADULTS .................................. 29
Appendix 4 - Fomu ya Idhini Ili Kushiriki Katika Utafiti- (Watu Wazima) .............. 31
Appendix 5 – Fomu Ya Idhini (Watu Wazima). ......................................................... 34
iv
LIST OF ACRONYMS AND ABBREVIATIONS
BMI
Body Mass Index
CDC
Center for Disease Control
KNH
Kenyatta National Hospital
TKR
Total Knee Replacement
v
ABSTRACT
Background: Numerous TKR surgeries are performed daily in Kenyan Hospitals.
Existing research shows that infection is the most prevalent complication of TKR.
However, its incidence and risk factors in this environment have largely remained
unknown. This hinders adequate interrogation of preventive measures.
Objectives: To determine the incidence of infection, associated risk factors and outcomes
in patients undergoing Total Knee Replacement in varied hospitals in Kenya.
Study design: Retrospective and prospective study.
Study site: Orthopaedics units of KNH, Kijabe Hospital and Kikuyu Hospital.
Methodology: Patients who underwent total knee replacement surgery shall be recruited
retrospectively and prospectively. Baseline characteristics noted such as age, sex,
indication for surgery and presence of comorbidities. Patients followed up either via
hospital records or prospectively and Outcome variable, occurrence of infection recorded.
Statistical analysis: Data will be cleaned and entered into SPSS version 24.0 for data
analysis.
To describe characteristics of the study participants, means, standard deviation, medians
and ranges shall be used for continuous variables while frequencies and proportions will
be used for categorical variables.
Incidence of infection after TKR shall be derived as a proportion of patients who had
infection after TKR out of the total sample size.
To identify the factors associated with the infection, Chi square test of independence shall
be used.
vi
For multivariate analysis, logistic regression shall be used to identify independent risk
factors for infection after TKR. Results of regression model shall be expressed in Odds
ratios and corresponding 95% confidence intervals.
P values of <0.05 shall be considered statistically significant.
Data shall be presented in frequency tables, pie charts, and bar charts.
Significance of the study: Existing research shows that infection is the most prevalent
complication of TKR. However, its incidence and risk factors in this environment have
largely remained unknown. This hinders adequate interrogation of preventive measures.
Therefore, the findings of this study will inform on local practice guidelines as well as
policy geared towards improving care of patients undergoing TKR.
vii
CHAPTER ONE
1.0 BACKGROUND
The knee, being the largest joint in the body, is required in most of our day-to-day
activities. A healthy knee is therefore required to ensure smooth, natural function and
movement[1]. Different disease processes causing destruction of the joint have warranted
surgical joint replacement overtime, making total knee replacement one of the most
common surgical procedures performed in Orthopedics, globally.
Total Knee Replacement, also referred to as Total Knee Arthroplasty, is the surgical
replacement of a diseased or worn out knee joint, with an artificial joint[2]. This is usually
performed in patients with joint diseases that have progressed and are refractory to
conservative management such as physiotherapy, analgesics and intraarticular steroid
injections. These joint diseases are known to cause chronic joint pain and reduced
mobility, which consequently causes other long-term complications. The two types of
knee replacement surgeries are total knee replacement, which involves involve replacing
the joint surface of femur and the joint surface at the top of tibia, and partial
(unicompartmental) knee replacement where only one portion of the knee is replaced[3].
Just like every other surgical procedure, knee replacement surgery has its own risks and
complications, following the procedure. Some of the commonest complications following
knee replacement include, but are not limited to, joint stiffness, hemorrhage, damage to
the adjacent structures during surgery (i.e., ligaments, nerves and blood vessels),
complications related to prolonged immobilization such as DVT, chronic knee pain,
wound infection, and infection of the prosthetic joint that could subsequently lead to
1
sepsis[2]. Prosthetic Joint Infection is the commonest and deadliest complication seen in
Total Knee Replacement. There are several recorded factors that could predispose a
patient to prosthetic joint infection, ranging from patient factors (modifiable and nonmodifiable factors), to intraoperative surgical techniques and health care system related
factors[4].
Previous research studies on prosthetic joint infection have highlighted the negative
impact of disease on every aspect of patients’ lives, and this has been attributed to the
heavy financial, physical and psychological burden of treatment imposed on patients and
their families by periprosthetic infections [5]. Surgical and antibiotic treatment has also
been seen to profoundly disrupt patients’ daily lives by changing the patients’ perception
and sense of self. Mobility and lifestyle limitations secondary to the chronic pain makes
the patients unable to do normal activities such as driving, working, sleeping, and carrying
out domestic duties.
The incidence of infection after total knee replacement has remained largely unknown as
well as factors associated with infection. The main aim of this study will be to investigate
the incidence of infection after total knee replacement and associated factors.
2
CHAPTER TWO
2.0 LITERATURE REVIEW
2.1 Definition of primary total knee replacement, prevalence and indications.
The use of total knee replacement (TKR) in the treatment of chronic degenerative diseases
of the knee has increased through the years, and this has been evidenced by the increase
in the number of publications worldwide[6]. Primary total knee replacement was designed
during early 1970s and has evolved over the past 50 years, with the growing incidence of
knee arthritis and due to its significant benefits.
Primary total knee replacement or primary total knee arthroplasty is basically replacement
of a knee joint with a prosthetic joint. This involves replacement of the articular surfaces,
which are the tibial plateau and the femoral condyles with metal, and polyethylene plastic
to improve the quality of life in patients suffering from end stage osteoarthritis, by
improving joint function and pain relief[7].
The United States records the highest incidence rate of knee arthroplasty at 235 in every
100,000 households. The 2010 Global Burden of Disease estimated the prevalence of knee
arthritis at 10-13% among Americans, which contributed to the increasing incidence rate
of knee arthroplasty in the United States[8]. A time trend study also reported an increase
of 58% in hospitalization due to TKR in the USA from approximately 145,242 in the year
2000 to 248,267 in 2006. This represented an increase in the incidence rate from 5.5% to
8.7% per 1,000 people in the population[9].
3
Although the prevalence rate of TKR due to osteoarthritis has increased through the years,
epidemiological studies from the Swedish Register have shown that the prevalence rate of
TKR due to rheumatoid arthritis remains unchanged.
Despite limitation of literature on joint replacement in the sub Saharan Africa, an
observational study in Ghana reported 82 knee replacements being performed in 86
patients in two different hospitals, with degenerative osteoarthritis being the most
common indication for the surgery[10].
Nairobi city in Kenya, has been reported to have the highest number of knee replacement
procedures in Eastern Africa[11], with osteoarthritis also being the main indication.
Other than degenerative osteoarthritis, other indications for TKR include inflammatory
arthritis like rheumatoid arthritis, joint malignancies or metastatic lesions to the joint,
fractures that increase the risk of avascular necrosis, and dysplasia, among others.
2.2 Complications of TKR.
Just like any other surgical procedure, TKR carries its own complications, from the point
of care intraoperatively to post operative care. Complications are very important in
assessing for outcomes of operative procedures in medical practice, as it guides in creating
better systems to improve the quality of healthcare in a given population. In the assessment
of outcome measures and quality of surgical procedures, surgical literature has used
complications to compare the safety, quality and efficacy of surgical treatments and
surgical implants.
Healey et al. emphasized on the need to differentiate between an adverse event from a
complication, stating that not all adverse events are complications. One of the examples
4
used was based on CDC definition of a surgical site infection, in reporting the
complication of deep periprosthetic joint infection. CDC defines a surgical site infection
as an infection that presents within 1 year of the first operation. Past one year, the infection
is considered an adverse event, and most of these are directly associated to the medical
and surgical treatments[12].
Complications associated with TKR can be clearly classified as perioperative
(intraoperative and post operative) or as immediate and late complications. Intraoperative
complications include, damage or injury to the adjacent structures such as blood vessels,
which can cause profuse bleeding therefore increasing the need for blood transfusion and
surgical repair, nerve injury causing neural deficits, and ligamentum injury needing
surgical repair. All intraoperative complications can also be seen post operatively.
Post operative complications are the most common, with the two most common being,
deep periprosthetic joint infections, where a sinus tract may be communicating with the
prosthesis[12], and wound infections that would require surgical revisions. Some of the
post operative complications are associated to prolonged immobilization before the
patient is able to bear weight. These include, deep venous thrombosis[13] and subsequent
pulmonary embolism, stiffness due to limited range of motion, hypostatic pneumonia,
psychological and mental anxiety.
Other post operative complications include, instability and malalignment, periprosthetic
and implant fracture, loosening of the implant[14] and implant failure, tibiofemoral and
patellofemoral dislocation[15], reoperation, readmission, revision, and increased
mortality rate.
5
2.3 Epidemiology of infection after primary TKR.
Infection, as a complication of TKR, is one of the most devastating outcomes of knee
replacement. Although several steps have been made to reduce the occurrence of
prosthetic infections such as antibiotic prophylaxis, aseptic techniques intra operatively
like proper skin preparation, infection still seems to be a burden to the orthopedic
surgeons.
One study showed that periprosthetic joint infection accounted for 46% of implant failures
after TKR. The study was a retrospective review of 476 patients who had undergone 499
surgical revisions after TKR between March 1998 and December 2005. Forty-four of the
patients, which translated to 9%, developed deep prosthetic infection, with the rate of
infection being higher in patients undergoing surgical or medical revision for infection
(21%), than in patients with aseptic revisions (5%). It was concluded that the risk of
infection for patients undergoing TKR revisions was 10 times higher than in patients
undergoing primary TKR[16].
Xiong et al. recorded an overall infection rate of 1.10%, with superficial surgical site
infection having an incidence rate of 0.66% and 0.44% for deep prosthetic joint
infection[17]. This was in a prospective study of 905 patients who underwent partial knee
arthroplasty, to determine whether longer duration of surgery contributed to the
occurrence of surgical site infections.
A retrospective review of 6489 total knee replacements was done by Peersman et al. to
determine the incidence rate of infection in that population. 116 knees were reported to be
infected and only 113 were available for follow up. 100 of the infections occurred in
patients undergoing primary knee replacement, while the remaining infections occurred
6
in patients undergoing revision knee replacement. 86% developed deep periprosthetic
infections while the rest had superficial wound infections[18]. A third of the deep
prosthetic infections occurred within the first 3 months post-op while the remaining two
thirds occurred after 3 months.
About 23%–25% of revision procedures following knee arthroplasty are due to infection
according to data from the USA and the UK. Data from the national SSI surveillance
program in England illustrated a one-year time course from surgery to infection. 85% of
the infections occurred within the initial one-month post-surgery, with an average duration
to infection of two weeks. Of the infections detected over the first year, 42% were
superficial incisional site infections, 43% were deep infections, and 15% were organ/space
infections. Superficial incisional infections were recorded within the first month postsurgery[19].
2.4 Risk factors for infection after TKR
Several risk factors, predisposing patients to infections after TKR have been identified.
These risk factors have been classified into patient related factors and surgical factors.
The incidence of increased risk between those undergoing revision arthroplasty and those
undergoing primary knee arthroplasty ranges between 0% to 10%, but current literature
does not report significant difference in the risk stratification.
Surgical factors that influence the occurrence of infection after TKR include sterile glove
changing, pre-op skin preparation, long duration of surgery, one-stage total knee
replacement surgery, bleeding and post-op hematoma, anti-microbial prophylaxis and
topical anti-bacterial preparations, and wound care[4]. Long duration of wound exposure
in prolonged duration of surgery was directly associated to increased risk of infection.
7
The pre-operative status of the patient is an important factor in determining wound healing
and the general outcome after TKR. National surveillance data from England for knee
replacement patients illustrates an elevated SSI risk in underweight and overweight
patients. Obese patients, with BMI more than 30 kg/m2, have double the rate of infection
compared to that of patients with normal weight, which is considered to be BMI between
18.5–24.9 kg/m2. The average BMI of patients undergoing primary knee replacement in
England and Wales has been noted to be increasing, reaching 28.6 and 30.6, respectively,
in 2011,[20] indicating that the attributable risk of infection due to obesity may
substantially increase in the UK.
Other patient related factors predisposing to infection include age, smoking, chronic
alcohol use, male gender, other comorbid diseases such as rheumatoid arthritis,
hypertension, peripheral vascular diseases, diabetes mellitus and other autoimmune
diseases, previous fracture adjacent to the knee, and wound-related complications[16].
Kurtz et al. reported a lower risk of infection in women as compared to men, and an
increased risk of infection in patients with comorbid conditions[19]. The
immunosuppressive drugs administered in Rheumatoid Arthritis inhibit proper wound
healing, making the patients prone to infections[21]. This applies to other autoimmune
diseases as well. Diabetes in itself is an immunosuppressive state, predisposing patients
undergoing TKR to infections.
Older patients are vulnerable to post-total knee arthroplasty infection due to weakened
immune resistance and poor nutritional status. However, Muilwijk et al. and Baier et al.
revealed no significant association between age and surgical site infection after primary
TKR[22][23].
8
Several articles have reported on the relationship between alcohol abuse and surgical site
infections. Wu et al. and Poultsides et al. reported that alcohol abuse of 45 g/day for men
and 30 g/day carried a 1.57- to 2.95-fold higher risk of Prosthetic Joint Infection[24] [25].
Excessive alcohol use impairs liver function and a weakens the immune system impairing
wound healing.
2.5 Outcomes of infection
The outcome of infection after TKR is dependent on prompt recognition and management
of the infections. Most cases are adequately managed with a series of targeted antibiotic
therapy while other cases, depending on the severity, require several cycles of
debridement, given concurrently with antibiotic therapy. Most superficial surgical
infections occur within the first month post-op and are self-limiting with oral antibiotics.
The rate of mortality and morbidity following infections after TKR is high due to
increased risk of sepsis and multi organ failure.
Cahill et al. in a study to evaluate the quality of life after infection in Total Joint
Replacement, reported that there was a significantly poor satisfaction and disease-related
functional outcomes in patients with complicated TJR[26]. One in five patients reported
dissatisfaction after TKR, majorly due to varus malalignment[27].
Another study by Tesfaye et al., to establish the outcome of revision surgery for infection
after TKR, indicated good results with irrigation and debridement [28]compared to other
studies. The overall outcome of 1- stage revision compared to 2- stage was similar,
although 1-stage revisions were shown to be associated with increased risk of recurrent
revisions in older patients, compared to 2-stage revisions. The mortality rate after revision
for PJI was 1.2% for 90 days and 2.5% for one year[29].
9
Several studies have reported very good outcomes with only a few deep prosthetic
infections requiring revision surgery[17]. A few other studies have shown a 5% incidence
rate of amputation after infected arthroplasty and this was attributed to life threatening
sepsis and persistent infection not responding to antibiotics, associated with massive bone
loss[30].
2.6 Gaps in literature in sub-Saharan Africa
Despite total knee replacement being one of the most common joint replacement surgery,
there is paucity of data on complications of total knee replacement surgery especially in
the Sub-Saharan Africa and Kenya. The incidence of infection after TKR and the
associated risk factors have largely remained unknown. This hinders adequate evaluation
of outcomes of the surgery.
2.7 Justification.
Lack of data in this field has hindered adequate assessment of the outcomes of TKR. It is
important to adequately develop data to improve audit of successes and failures of TKR.
Numerous TKR surgeries are performed every day in Kenyan Hospitals. Existing research
shows that infection is the most prevalent complication of TKR. However, its incidence
and risk factors in this environment have largely remained unknown. This hinders
adequate interrogation of preventive measures. Therefore, the findings of this study will
inform on local practice guidelines as well as policy geared towards improving care of
patients undergoing TKR.
10
2.8 Research Questions
1. What is the incidence of infection after total knee replacement?
2. What are the factors associated with infection after TKR?
3. What are the outcomes of patients with infection after TKR?
2.9 Study Objectives
2.9.1 Broad objective
To determine the incidence of infection, associated risk factors and outcomes in patients
undergoing Total Knee Replacement in varied hospitals in Kenya.
2.9.2 Specific objectives
1. To determine the incidence of infection after total knee replacement surgery.
2. To establish the risk factors for infection after total knee replacement.
3. To determine the outcomes of patients with infection after TKR.
11
2.10 Conceptual framework
12
CHAPTER THREE
3.0 METHODOLOGY
3.1 Study design
A retrospective and prospective cross-sectional study.
3.2 Study Site
This study will be conducted at Kenyatta National Hospital Orthopaedics Clinics, Kikuyu
Hospital Orthopaedics Clinics and Kijabe Hospital Orthopaedics clinics. KNH is the
national referral hospital in Kenya of all public hospital in Kenya, with significant number
of knee replacement surgeries taking place at the institution. Similarly, Kikuyu and Kijabe
Hospitals are Orthopaedics specialist centers with significant number of procedures being
performed in those institutions.
3.3 Study population
The study population will consist of patients who underwent or are undergoing primary
total knee replacement during the study period.
3.4 Inclusion and Exclusion Criteria
3.4.1. Inclusion criteria

All patients who underwent primary total knee replacement surgery at the selected
hospitals.

.
13
3.4.2
Exclusion Criteria.

Missing relevant records

Patients who underwent revision TKR.

Refusal to consent to participate in the study.

Less than 3 months after undergoing total knee replacement.
3.5 Sample Size Determination
Fisher’s et al formula will be used to calculate the sample size
N= Z2 p {1-p}
D2
N = Sample size.
Z = Standard error from the mean corresponding to 95% confidence level = 1.96
P = 50% since it gives maximum variability in sample size. No studies exist in the local
region to show incidence of infection after total knee replacement surgery.
D = Precision/ reliability with which to determine P = 5%
N = 1.96 x 1.96 x 0.5 (1-0.5)
0.05 x 0.05
N = 3.8416 x 0.5 x 0.5
0.0025
N = 384
14
3.6 Sampling Procedure
Total number of 384 patients will be recruited by consecutive sampling technique. If the
selected patient is not eligible or declines consent to participate in the study, the next most
eligible patient will be approached for possible enrollment. This will be repeated until the
sample size of 384 is attained.
3.7 Variables
3.7.1 Dependent variables
1. Infection after knee replacement surgery
2. Revision surgery.
3.7.2 Independent variables

Age,

Sex

Comorbidities such as diabetes

Indication for Knee replacement surgery

Hospital where procedure was carried out
3.8 Data Collection
There will be a structured data collection sheet used to collect data. For the retrospective
arm, the source of demographic data will be patient's medical records. The primary
investigator assisted by Research assistants will review medical records of patients who
underwent TKR during the study period.
15
For the prospective arm, patients who recently underwent TKR will be followed up for 3
months to observe occurrence of infection.
3.8.1Recruitment and Training procedures
Research assistants, some of whom will be medical students in Year 5 and 6, will be
trained for one day on what the study protocols and what is required of them from the
principal investigator. They will be trained on how to fill the data collection tool in a
standardized and uniform manner.
3.9 Quality assurance measures
Pretesting of the data collection tool will be done by interviewing 5% of desired sample
size. This will help in estimating the total time it would take to complete one form and the
efficacy of the tool in capturing adequate data. All questions should be filled on the tool.
3.10 Ethical Considerations
Departmental clearance to conduct the study will be obtained from the department of
orthopaedics surgery.
Subsequently, permission to carry out the study will be sought from Kenyatta National
Hospital/ University of Nairobi Ethics and Research Committee.
Written informed consents will be obtained from all the participants after the purpose of
the study is explained.
Participation to this study will be voluntary and there will be no offering of incentives,
gifts or refunds. Confidentiality will be maintained for all obtained information and no
names will be written on the questionnaire.
16
This study has no risks as no drugs will be given, no procedures and no specimen will be
taken.
Declining to participate in the study will not affect the quality of care they will receive.
3.11 Data Management
Data shall be entered into password protected Microsoft Excel spreadsheet. Only the
principal investigator and the authorized personnel shall be allowed to access the data.
All hard copy data collection tools shall be place under lock and key to avoid unauthorized
access.
3.12 Data Analysis
Data will be cleaned and entered into SPSS version 24.0 for data analysis.
To describe characteristics of the study participants, means, standard deviation, medians
and ranges shall be used for continuous variables while frequencies and proportions will
be used for categorical variables.
Incidence of infection after TKR shall be derived as a proportion of patients who had
infection after TKR out of the total sample size.
To identify the factors associated with the infection, Chi square test of independence shall
be used.
For multivariate analysis, logistic regression shall be used to identify independent risk
factors for infection after TKR. Results of regression model shall be expressed in Odds
ratios and corresponding 95% confidence intervals.
17
P values of <0.05 shall be considered statistically significant.
Data shall be presented in frequency tables, pie charts, and bar charts.
3.13 Data dissemination
Once data is analyzed and manuscript developed, study findings shall be disseminated
with relevant stakeholders such as orthopedics units of the varied hospitals. The
manuscript shall also be published in a peer reviewed medical journal.
3.14 Study Limitations
Loss of data. Lack of proper documentation and storage in the files and computers in
regards to the retrospective data.
Loss to follow-up. Patients on the prospective arm may be lost to follow-up.
DUMMY TABLE
Dummy table showing associations with occurrence of infection
Variable
Category
Infection after TKR
Yes
Age
No
<65
>65
Sex
Male
Female
Comorbidities
Yes
No
Indication
TKR
for Yes
No
18
P value (Chi
square)
STUDY BUDGET
ITEM
QUANTITY
Research fees for KNH-UON
Standard
ERC
cost
Stationary
Printing
TOTAL COST
5,000
7,000
Paper,Pens,
Document
Folders
Statistician fees
40,000
Research assistant
50,000
Printing and Binding
25,000
Contingencies
5,000
Total
132,000
19
STUDY TIME FRAME
Jan 2022 – Sep 2022 – Jan 2023 – April 2023
ACTIVITY
Aug 2022
Dec 2022
PROPOSAL
DEVELOPMENT
ETHICAL APPROVAL
DATA COLLECTION
DATA ANALYSIS
DISSERTATION
WRITING
SUBMISSION
AND
20
March 2023
May 2023
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21
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14. Complications of Total Knee Arthroplasty: Background, Complications, Long-Term
Problems. 2022 May 12 [cited 2022 Jul 26]; Available from:
https://emedicine.medscape.com/article/1250540-overview
15. Ayas MS, Kalkışım M, Köse A, Gül O. Complications after Total Knee Arthroplasty
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16. Mortazavi SMJ, Schwartzenberger J, Austin MS, Purtill JJ, Parvizi J. Revision Total
Knee Arthroplasty Infection: Incidence and Predictors. Clin Orthop. 2010
Aug;468(8):2052–9.
17. Teo BJX, Yeo W, Chong HC, Tan AHC. Surgical site infection after primary total
knee arthroplasty is associated with a longer duration of surgery. J Orthop Surg Hong
Kong. 2018 Aug;26(2):2309499018785647.
18. Peersman G, Laskin R, Davis J, Peterson M. Infection in total knee replacement: a
retrospective review of 6489 total knee replacements. Clin Orthop. 2001
Nov;(392):15–23.
19. Prosthetic joint infection risk after TKA in the Medicare population - PubMed
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20. Surgical site infection surveillance service (SSISS) [Internet]. GOV.UK. [cited 2022
Jul 26]. Available from: https://www.gov.uk/guidance/surgical-site-infectionsurveillance-service-ssiss
21. Momohara S, Kawakami K, Iwamoto T, Yano K, Sakuma Y, Hiroshima R, Imamura
H, Masuda I, Tokita A, Ikari K. Prosthetic joint infection after total hip or knee
arthroplasty in rheumatoid arthritis patients treated with nonbiologic and biologic
disease-modifying antirheumatic drugs. Mod Rheumatol. 2011 Oct;21(5):469–75.
22. Muilwijk J, Walenkamp GHIM, Voss A, Wille JC, van den Hof S. Random effect
modelling of patient-related risk factors in orthopaedic procedures: results from the
Dutch nosocomial infection surveillance network “PREZIES.” J Hosp Infect. 2006
Mar;62(3):319–26.
23. Baier C, Adelmund S, Schwab F, Lassahn C, Chaberny IF, Gossé F, Vonberg RP,
Ebadi E. Incidence and risk factors of surgical site infection after total knee
arthroplasty: Results of a retrospective cohort study. Am J Infect Control. 2019
Oct;47(10):1270–2.
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and risk factors. J Arthroplasty. 2013 Mar;28(3):385–9.
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Replacement. J Orthop Surg. 2008 Apr 1;16(1):58–65.
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23
LIST OF APPENDICES
Appendix 1: Data collection tool
Title:
INCIDENCE OF INFECTION AND ASSOCIATED
FACTORS AFTER PRIMARY TOTAL KNEE REPLACEMENT
Investigator: Dr. Caleb Karuga, Resident Department of Orthopedics and
Trauma Surgery, University of Nairobi
Form no: ……..
1. Age…….. years
2. Sex: Male / Female
3. Indication for knee replacement surgery
i. …..
ii. ……
4. Comorbids
i. Diabetes
Yes / No
ii. ..
iii. ..
5. Infection after TKR: Yes / No
6. Type of infection:
i. Superficial
24
ii. Deep
7. Duration of occurrence of infection after TKR….. days
8. Outcomes of infection
a. Resolved with Antibiotics
b. Revision surgery
Yes / No
Yes/No
25
Appendix 2: Informed consent – English Version
PARTICIPANT INFORMATION AND CONSENT FORM FOR ENROLLMENT
IN THE STUDY: ADULT PATIENT CONSENT FORM
Title of Study: INCIDENCE OF INFECTION AND ASSOCIATED FACTORS
AFTER PRIMARY TOTAL KNEE REPLACEMENT
Principal Investigator: Dr. Caleb Karuga
Institution: Resident at The University of Nairobi, Department of Orthopaedics Surgery.
Introduction:
I am Dr Caleb Karuga. I am currently pursuing my postgraduate studies at the University
of Nairobi. As part of my studies, I am required to undertake research. I am doing research
to document the rates of infection after Total Knee replacement Surgery at Kenyatta
National Hospital, Kikuyu and Kijabe Hospitals. The purpose of this consent form is to
provide you with adequate information in order to help you decide whether or not to be a
participant in the study. You are free to ask any questions about the research, its purpose,
implications of participating in the study, risks and benefits, volunteer rights, and any
added information not included in this form that needs clarification. After your questions
are satisfactorily answered, you can decide to take part in the study or not. This process is
known as 'informed consent'. After you agree to take part in this study, I will request you
to sign your name on this form.
You should understand the general principles which apply to all participants in a medical
research:
i)
Participation in the study is on voluntary basis.
ii)
You have a right of withdrawal from the study at any time without necessarily
giving a reason for your withdrawal.
iii)
If you refuse to take part in the study, this does not in any way affect services
provided to you in the facility or any other health facility.
A copy of this form will be provided to you for your records.
26
May I continue? YES / NO
This study has approval by The Kenyatta National Hospital-University of Nairobi Ethics
and Research Committee Protocol No. ____________________________
What Is This Study About?
The above researchers are interviewing individuals who are undergoing fetal anomaly
scans. The reason for the interview is to find out your progress after TKR. All those who
take part in this research study will also have imaging and blood tests reviewed. There are
no further investigations or tests required. There will be approximately 384 participants
in this study who are randomly chosen. We request for your consent to consider taking
part in this study.
What Will Happen If You Decide To Be In This Research Study?
If you agree to take part in this research, the following will happen:
You will be interviewed in an area where your privacy guaranteed and you are comfortable
to answer questions. The interview will take few minutes. After the interview has finished,
I will request to go through your ultrasound report. If necessary, we will ask your phone
number to contact you. Any contact information you provide will be used only by people
conducting this study and will never be shared with others.
Are There Any Risks, Harms Discomforts Associated with This Study? Generally,
medical research has the potential to introduce psychological, social, emotional and
physical risks. One of the risks of being in the study is loss of privacy. Any information
you give us is confidential and we will keep it private. We will identify you with a codenumber in a password-protected computer database and all our paper records will be kept
in a secure cabinet. You have the right to decline the interview or any questions asked in
the process. Also, all our staff conducting this study are professionals with training in
these examinations/interviews.
Are There Any Benefits Being In This Study?
The study will help us understand better the rates of infection after Total knee replacement
surgery and contributing factors at Kenyatta National Hospital and other selected
hospitals. This will further enable us to create feasible local guidelines guiding the same.
27
Will Being In This Study Cost You Anything?
No additional costs will be incurred.
Can I Withdraw From The Study Anytime?
Participation in the study is on voluntary basis and you have a right of withdrawal from
the study and that at anytime you can decide to withdraw from the study without
necessarily giving a reason for your withdrawal. This does not in any way affect services
provided to you in the facility or in any other health facility.
For more information about your rights as a research participant you may contact the
following persons:
Principal investigator:
Dr. Caleb Karuga
Telephone no.: +2547
Department of Orthopedics and Trauma surgery
University of Nairobi,
Lead Supervisor:
Dr.
Department of Orthopedics and Trauma surgery,
University of Nairobi.
Tel no.:+2547.
Or
The Secretary,
Kenyatta National Hospital-University of Nairobi Ethics and Research Committee
Telephone No. 2726300 Ext. 44102
Email: uonknh_erc@uonbi.ac.ke.
28
Appendix 3- Consent Form (Statement of Consent)-ADULTS
Participant’s statement
1. I have read this consent form or had the content read to me and I understood.
2.
I have been given the chance to ask questions about this research study.
3. I have had my questions answered adequately in a language I understand.
4. The potential risks and benefits have been explained to me in a clear and precise
manner.
5.
I understand that I take part in this study voluntarily and that I can withdraw
anytime.
By signing this consent form, I have not given up any of the legal rights that I have as a
participant in a research study.
I agree to participate in this research study: Yes/ No
I agree to provide contact information for follow-up: Yes /No
Participant
printed
name:
_________________________________________________________
Contact (mobile number): ______________________
Participant
signature
/
Thumb
stamp
_______________________
Date
_______________
Researcher’s statement
I, the undersigned, have fully explained the relevant details of this research study to the
participant named above and believe that the participant has understood and has willingly
and freely given his/her consent.
Researcher ‘s Name: Dr. Caleb Karuga
Date: _______________
Signature
_____________________________________________
Role in the study: Principal investigator.
29
For more information,contact:
Principal investigator:
Dr. Caleb Karuga
Telephone no.: +2547
Department of Orthopedics and Trauma surgery
University of Nairobi,
Lead Supervisor:
Dr.
Department of Orthopedics and Trauma surgery,
University of Nairobi.
Tel no.:+254719244869.
Or
The Secretary,
Kenyatta National Hospital-University of Nairobi Ethics and Research Committee
Telephone No. 2726300 Ext. 44102
Email: uonknh_erc@uonbi.ac.ke.
30
Appendix 4 - Fomu ya Idhini Ili Kushiriki Katika Utafiti- (Watu Wazima)
Kichwa Cha Utafiti:. :
INCIDENCE OF INFECTION AND ASSOCIATED
FACTORS AFTER PRIMARY TOTAL KNEE REPLACEMENT
Mpelelezi Mkuu Na Ushirika Wa Kitaasisi: Dr.Caleb Karuga, Mwanafunzi wa Shahada
ya Uzamili Katika……………. Chuo Kikuu Cha Nairobi, Idara ya Magonjwa ya mifupa
Mimi ni Daktari……………; Hivi sasa ninaendelea na masomo yangu ya uzamili katika
Chuo Kikuu cha Nairobi. Katika masomo yangu, ninahitajika kufanya utafiti. Ninafanya
utafiti kuchunguza……...
Ningependa kukuambia juu ya utafiti unaofanywa na mtafiti aliyeorodheshwa hapo juu.
Madhumuni ya fomu hii ya idhini ni kukupa habari za kutosha ili kukusaidia kuamua
iwapo utakuwa mshiriki wa utafiti au la. Uko huru kuuliza maswali yoyote juu ya utafiti,
madhumuni yake, ni nini maana ya wewe kushiriki katika utafiti, ikiwa kuna hatari yoyote
inayohusika na faida yoyote, haki za kujitolea, na habari yoyote iliyoongezwa
isiyojumuishwa katika fomu hii na inahitaji ufafanuzi. Baada ya kujibu kwa kuridhisha
maswali yako yote, unaweza kuamua kushiriki katika utafiti au la. Utaratibu huu
unajulikana kama 'idhini ya habari'. Baada ya kukubali kushiriki katika utafiti huu,
nitakuomba utie sahihi jina lako kwenye fomu hii.
Unapaswa kuelewa kanuni za jumla ambazo zinatumika kwa washiriki wote katika utafiti
wa matibabu:
i.
Kushiriki katika utafiti ni kwa hiari.
ii.
Wakati wowote unaweza kuamua kujiondoa kwenye utafiti.
iii.
Ukikataa kushiriki katika utafiti, hii haiathiri huduma unayopewa katika
kituo hicho au kituo kingine chochote cha afya.
Tutakupa nakala ya fomu hii kwa rekodi zako.
Naweza kuendelea? NDIO AULA
Utafiti huu umeidhinishwa na Itifaki ya Kamati ya Maadili na Utafiti ya Hospitali ya
Kitaifa ya Kenyatta-Chuo Kikuu cha Nairobi Nambari__________
Utafiti Huu Unahusu Nini?
Watafiti hapo juu wanawahoji watu ambao wanapitia picha ya ujauzito kuchunguza ukuaji
mzuri wa kijusi. Sababu ya mahojiano ni kujua umri wako, idadi ya watoto na umri wa
ujauzito. Picha za ULTRASOUND za ujauzito za wote watakaoshiriki katika utafiti huu
31
zitakaguliwa na watafiti. Hakuna uchunguzi zaidi au vipimo vinahitajika. Kutakuwa na
takriban washiriki __________ katika utafiti huu ambao wamechaguliwa bila mpangilio.
Tunaomba idhini yako kufikiria kushiriki katika utafiti huu.
Je, Nini Kitatokea Ukiamua Kuwa Kwenye Utafiti Huu?
Ikiwa unakubali kushiriki katika utafiti huu, yafuatayo yatatokea:
Utahojiwa katika eneo ambalo faragha yako imehakikishiwa na unahisi vizuri kujibu
maswali. Mahojiano yatachukua dakika chache. Baada ya mahojiano kumalizika,
nitaomba kupitia …………….. Ikibidi, tutauliza nambari yako ya simu kuwasiliana nawe.
Maelezo yoyote ya mawasiliano utakayotoa yatatumika tu na watu wanaofanya utafiti huu
na hawatashirikiwa na wengine kamwe.
Je, Kuna Athari Zozote, Madhara, Usumbufu Zinazohusiana Na Utafiti Huu?
Kwa ujumla, utafiti wa matibabu una uwezo wa kuanzisha hatari za kisaikolojia, kijamii,
kihemko na kiafya. Moja ya hatari ya kuwa katika utafiti huu ni kupoteza faragha. Habari
yoyote unayotupatia ni ya siri na itachukuliwa kama siri.
Tutatumia nambari ya kukutambulisha kwenye hifadhidata ya kompyuta inayolindwa na
nywila na rekodi zetu zote za karatasi zitahifadhiwa kwenye baraza la mawaziri
iliyofungwa. Una haki ya kukataa mahojiano au maswali yoyote yanayoulizwa katika
mahojiano. Pia, wafanyikazi wetu wote wanaofanya utafiti huu ni wataalamu wenye
mafunzo katika mitihani / mahojiano haya.
Je, Kuna Faida Zozote Ziko Katika Utafiti Huu?
Utafiti huo utatusaidia kuelewa vizuri jinsi …………………….. za kuchunguza ukuaji
mzuri wa kijusi. Hii itapanua zaidi ufahamu wetu………………..
Je, Kuna Gharama Kuwa Katika Utafiti Huu?
Hakuna gharama za ziada zitakazopatikana.
Je, Ninaweza Kuondoka Kwenye Utafiti Wakati Wowote?
Kushiriki katika utafiti ni kwa hiari na una haki ya kujiondoa kutoka kwa utafiti na
kwamba wakati wowote unaweza kuamua kujiondoa kwenye utafiti bila lazima kutoa
sababu ya kujitoa kwako. Hii haiathiri kwa vyovyote huduma unazopewa katika kituo
hicho au katika kituo kingine chochote cha afya.
32
Kwa habari zaidi juu ya haki zako kama mshiriki wa utafiti unaweza kuwasiliana na watu
wafuatao:
Mchunguzi Mkuu:
Dr. Caleb Karuga
Nambari ya Simu.: +2547
Department of Orthopedics and Trauma surgery
University of Nairobi,
Msimamizi Mkuu:
Dr.
Department of Orthopedics and Trauma surgery
University of Nairobi.
Nambari ya Simu:+254
Ama,
Katibu,
Kenyatta National Hospital-University of Nairobi Ethics and Research Committee
Nambari ya simu :. 2726300 Ext. 44102
Email:uonknh_erc@uonbi.ac.ke.
33
Appendix 5 – Fomu Ya Idhini (Watu Wazima).
Kichwa Cha utafiti: :
INCIDENCE OF INFECTION AND ASSOCIATED
FACTORS AFTER PRIMARY TOTAL KNEE REPLACEMENT
Jina la Mtafitu: Dr. Caleb Karuga, mwanafunzi wa Shahada ya Uzamili Katika
Radiology Chuo Kikuu cha Nairobi, Idara ya ……………
1. Nimesoma fomu hii ya idhini au nimesomewa yaliyomo na nilielewa.
2. Nimepewa nafasi ya kuuliza maswali juu ya utafiti huu.
3. Nimejibiwa maswali yangu vya kutosha katika lugha ninayoelewa.
4. Hatari na faida zinazowezekana nimeelezewa kwa njia wazi.
5. Ninaelewa kuwa mimi hushiriki katika utafiti huu kwa hiari na kwamba ninaweza
kujiondoa wakati wowote.
Kwa kusaini fomu hii ya idhini, sijatoa haki yoyote ya kisheria ambayo ninayo kama
mshiriki wa utafiti.
Ninakubali kushiriki katika utafiti huu: Ndio / Hapana
Ninakubali kutoa habari ya mawasiliano kwa ufuatiliaji: Ndio / Hapana
Jina
la
mshiriki
aliyechapishwa:
_________________________________________________________
Mawasiliano (nambari ya rununu): ______________________
Saini ya mshiriki / Stempu ya kidole gumba _______________________ Tarehe
_______________
Kauli ya mtafiti
Mimi, aliyesainiwa chini, nimeelezea kabisa maelezo yanayofaa ya utafiti huu kwa
mshiriki aliyetajwa hapo juu na ninaamini kwamba mshiriki ameelewa na kwa hiari
ametoa idhini yake.
Jina la mtafiti: DR. Caleb Karuga: _______________
Saini
_______________________________________________________________________
Wajibu katika utafiti: Mchunguzi mkuu.
Kwa habari zaidi, wasiliana na:
Mchunguzi Mkuu:
34
Dr. Caleb Karuga,
Nambari ya Simu.:
Department of Orthopedics and Trauma surgery
University of Nairobi,
Msimamizi Mkuu:
Dr.
Department of Orthopedics and Trauma surgery
University of Nairobi.
Nambari ya Simu:
Ama,
Katibu,
Kenyatta National Hospital-University of Nairobi Ethics and Research Committee
Nambari ya simu :. 2726300 Ext. 44102
Email:uonknh_erc@uonbi.ac.ke.
35