924 - Early Patellar Tendon Rupture: A Rare Complication of Total Knee Arthroplasty Misinterpreted as Cellulitis: A Case Report

Thursday, February 19, 2026

5:00 PM - 6:30 PM AST

Presenting Author(s)

RK

Rhea Kohli, BS

Medical Student
Burrell College of Osteopathic Medicine
Apple Valley, Minnesota, United States

Co-Author(s)

SA

Siam S. Ayon, DO, MS

Resident Physician
Burke Rehabilitation Hospital
White Plains, New York, United States
JH

Jennifer Hegedus, DO

Resident Physician
Burke Rehabilitation Hospital
White Plains, New York, United States
AT

Andrew Tom, MD

Attending Physician
Burke Rehabilitation Hospital
White Plains, New York, United States

Submitter(s)

RK

Rhea Kohli, BS

Burrell College of Osteopathic Medicine
Apple Valley, Minnesota, United States

Case Diagnosis: Patellar Tendon Rupture following Right Total Knee Arthroplasty

Case Description: An 86-year-old female with a past medical history of hypertension, dyslipidemia, atrial fibrillation, diastolic heart failure, diabetes mellitus, chronic kidney disease, and osteoarthritis presented two days status-post right total knee arthroplasty (TKA) for acute inpatient rehabilitation. Upon admission, the patient tolerated therapies with some pain and peri-incision edema. As she progressed, the patient developed red discoloration of the skin surrounding the right knee, which spread throughout the leg and was warm to the touch. Given these findings, cellulitis of the surgical knee was suspected. However, multiple, subsequent IV antibiotic regimens resulted in minimal improvement of her symptoms with worsening pain upon movement. Repeat imaging performed two weeks post-op revealed rupture of the right patellar tendon, highlighting the potential for misdiagnosis and the need for a thorough evaluation in such cases.

Discussions: Patellar tendon rupture, a rare but devastating complication after total knee arthroplasty, is reported to have a prevalence between 0.7% and 1%. This rarity underscores the need for vigilance, as it can occur even in the absence of traumatic injury. Delayed, nonoperative treatment can lead to significant incapacitation and rehabilitation challenges for patients due to impaired knee extension. These commonly include chronic pain, limb and gait instability, extensor lag, and an increased risk for falls.

Conclusions: In this report, we discuss a challenging case of inconspicuous patellar tendon rupture in a patient status-post total knee arthroplasty, with a constellation of symptoms that initially pointed to suspected cellulitis. The lessons learned from this case underscore the urgency of prompt diagnosis when postoperative complications arise. This case serves as a reminder that patellar tendon rupture, although rare, should be considered in the differential, and the timely identification of such cases can significantly impact patient outcomes.