Pharmacogenomics Information in Enhancing Post-operative Total Joint Replacement Pain Management: a Pilot Study

This is a pilot study that will look at how pain management will be effected when
pharmacogenomic testing is utilized to select and dose narcotic pain medications prescribed
for breakthrough pain in post-operative total knee arthroplasty (TKA) patients. Patients will
receive individualized analgesics and doses for pain mitigation based on genetic testing
results. Post op pain scores, narcotic consumption, adverse reactions, length of stay and
patient satisfaction with pain management will be collected and analyzed to determine the
significance of the pharmacogenomic analgesic testing.

Due to the lack of literature and evidence surrounding pharmacogenomics and its use in
selecting analgesics to control post-operative pain a pilot study is being conducted to
evaluate effect size (statistical variability) in an attempt to predict an appropriate sample
size for a larger scale randomized control trial. The subjects enrolled and data collected
for this internal pilot will be used in the larger scale parent study as well.

Inclusion Criteria:

Patients undergoing total knee arthroplasty Patients able to understand study intent, and
agree to study participation. Patients with a history of preoperative narcotic dependence
and/or, adverse reactions to narcotics, and/or have experienced ineffective pain management
with narcotics.

Exclusion Criteria:

Patients with orthopaedic and medical co-morbidities that would thwart postoperative pain
control such as extra-articular pathology with referred pain to the knee (spinal stenosis,
neuropathy,ipsilateral hip disease), severe knee deformity, post-traumatic and inflammatory
arthritis Patients with chronic pain disorders BMI > 40 ASA class > III GI bleed within 6
months of surgery History of drug or alcohol abuse Patients unable to receive multimodal
pain remitting agents including Celecoxib and Pregabalin.

Patients with diabetes and patients who are unable to receive decadron Any patient
receiving general anesthesia Patients who will need to go to an ECF upon discharge Patients
who are pregnant