Amino-bisphosphonates in heterotopic ossification: first experience in five consecutive cases

Area of Science:

• Orthopedics
• Pharmacology
• Bone Metabolism

Background:

• Heterotopic ossification (HO) is a common complication after spinal cord injury and orthopedic surgery, often recurring after treatment.
• Existing treatments have limitations, with recurrence rates exceeding 50% for HO.
• Amino-bisphosphonates represent a newer class of drugs with potential for managing bone metabolism disorders.

Purpose of the Study:

• To investigate the efficacy of pamidronate in preventing HO recurrence in high-risk patients undergoing surgical removal.
• To assess the safety and potential side effects of pamidronate therapy in this patient group.

Main Methods:

• A retrospective, observational study involving five consecutive high-risk patients with established HO.
• Pamidronate was administered perioperatively via continuous infusion, with dosages adjusted over 10-14 days.
• Patients were monitored for clinical, radiological, and laboratory signs of HO recurrence and for potential side effects.

Main Results:

• No instances of HO recurrence or new HO formation were observed during a follow-up period of 5-54 months.
• No adverse effects associated with high-dose bisphosphonate therapy, such as osteoporosis or osteomalacia, were reported.
• Pamidronate treatment appeared to halt dysfunctional bone metabolism contributing to HO.

Conclusions:

• Pamidronate shows promise as a beneficial treatment for high-risk patients with established HO undergoing surgical excision.
• Further research is needed to define the therapeutic window, optimal dosage, and duration of pamidronate treatment for preventing HO recurrence.
• Identifying specific patient subgroups who would benefit most from pamidronate therapy requires additional investigation.