Skip to content

Opioid Use Is Similar After Patellofemoral Knee Arthroplasty and TKA

Key findings

  • This retrospective study compared self-reported opioid use at the first postoperative visit between patients who underwent patellofemoral knee arthroplasty (PFA), medial unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA)
  • A significantly greater proportion of patients who underwent PFA reported using opioids for pain management compared with patients who underwent UKA
  • There was no difference in the incidence of opioid use between TKA and PFA patients
  • Fewer UKA patients reported using opioids than those who underwent TKA

Postoperative opioid consumption has been fairly well characterized recently in patients undergoing total knee arthroplasty (TKA), including in a Massachusetts General Hospital study published in The Journal of Arthroplasty. By contrast, few studies have examined opioid use after unicompartmental knee arthroplasty (UKA), and none have evaluated whether opioid use is similar after UKA and patellofemoral knee arthroplasty (PFA).

Orthopedic Surgeons Christopher M. Melnic, MD, and Hany S. Bedair, MD, at the Center for Hip & Knee Replacement at Mass General, and colleagues have determined that the percentage of patients using opioids for pain relief one month after PFA is similar to the percentage of TKA patients who are using opioids at that time point and significantly greater than after medial UKA. Their report is published in The Knee.

Study Design

The researchers retrospectively studied 100 patients who underwent unilateral medial UKA or PFA at Mass General between 2011 and 2017. Pain management protocols were similar for the two surgeons involved and did not change during the study period. The 35 patients who underwent PFA (37 procedures) and the 65 patients who underwent UKA (71 procedures) were matched by age and sex to 108 patients who underwent unilateral TKA during the same time period. There were no significant differences between the TKA, UKA and PFA groups in the number of patients who reported any preoperative opioid use.

Rates of Opioid Use

  • At the first postoperative visit, about 30 days after surgery, significantly more patients who underwent PFA than patients who underwent UKA reported taking opioids to manage postoperative pain (38% vs. 11%; P < .001)
  • In the TKA group, 41% of patients reported opioid use at the first postoperative visit, significantly more than in the UKA group (11%) and statistically similar to the rate in the PFA group (38%)

Frequency of Opioid Use

  • PFA group: 50% of the patients using opioids said they required it occasionally to aid sleep or prior to physical therapy; 50% said they used it regularly for pain
  • UKA group: 43% occasional use; 57% regular use
  • TKA group: 35% occasional use; 64% regular use


Pain management protocols for patients undergoing PFA should be similar to those for TKA patients and separate from those for UKA patients. To optimize outcomes, it is crucial for surgeons and patients to have appropriate expectations about postoperative pain management.

of patients who underwent patellofemoral knee arthroplasty were still using opioids occasionally or regularly one month after surgery

of patients who underwent medial unicompartmental knee arthroplasty were still using opioids occasionally or regularly one month after surgery

of patients who underwent total knee arthroplasty were still using opioids occasionally or regularly one month after surgery

Learn more about the Center for Hip and Knee Replacement at Mass General

Refer a patient to the Center for Hip and Knee Replacement at Mass General


Orthopedic surgeons at Massachusetts General Hospital became the first to investigate how the recently introduced bicruciate-retaining total knee arthroplasty affects in vivo kinematics, articular contact position and pivot point location during gait.


In patients with hepatitis C infection who are treated prior to total knee arthroplasty, achieving a sustained virologic response significantly reduces the risk of postoperative complications, including prosthetic joint infection and the need for revision.