Heterotopic Ossification at Tracker Pin Sites Following Robotic-Assisted Total Knee Arthroplasty

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Radiology

Background:

• Total knee arthroplasty (TKA) is a common procedure for osteoarthritis.
• Robotic-assisted surgery offers potential benefits but may introduce unique complications.
• Heterotopic ossification (HO) is the abnormal formation of bone in soft tissues.

Purpose of the Study:

• To report a case of heterotopic ossification (HO) at Mako robotic-assisted total knee arthroplasty (TKA) tracker pin sites.
• To highlight a potential complication associated with robotic-assisted TKA.

Main Methods:

• A case report of a 72-year-old male patient who underwent Mako robotic-assisted TKA.
• Clinical evaluation including range of motion (ROM) assessment.
• Radiographic imaging to identify a calcified mass.
• Surgical excision of the heterotopic ossification.
• Pharmacological treatment with indomethacin.

Main Results:

• The patient developed limited knee flexion and discomfort postoperatively.
• Radiographs revealed a large, calcified mass at the distal femur tracker pin sites, consistent with HO.
• Surgical excision of the HO was performed, and indomethacin was initiated.

Conclusions:

• Heterotopic ossification (HO) is a potential complication of Mako robotic-assisted TKA, specifically at tracker pin sites.
• Postoperative stiffness in patients undergoing robotic-assisted TKA may indicate HO development.
• Awareness of this complication is crucial for surgeons performing robotic-assisted procedures.