Recombinant human bone morphogenetic protein-2 accelerates healing in a rabbit ulnar osteotomy model

Area of Science:

• Orthopedics
• Regenerative Medicine
• Biomaterials

Background:

• Delayed or impaired fracture healing affects 5-20% of fractures.
• New therapies are needed to augment traditional fracture repair methods.
• Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a potential therapeutic agent.

Purpose of the Study:

• To evaluate the efficacy of a single application of rhBMP-2 in accelerating fracture healing.
• To assess rhBMP-2's impact on a rabbit ulnar osteotomy model with spontaneous healing.

Main Methods:

• Seventy-two rabbits underwent bilateral mid-ulnar osteotomies.
• Osteotomies were treated with rhBMP-2 on a collagen sponge, buffer on a sponge, or left untreated.
• Bone healing was assessed via peripheral quantitative computed tomography and torsional biomechanical testing at 2, 3, 4, and 6 weeks.

Main Results:

• rhBMP-2 treatment increased mineralized callus area by 20-60% at 3-6 weeks compared to controls (p < 0.05).
• Biomechanical properties were at least 80% greater in rhBMP-2 treated groups at 3-4 weeks (p < 0.01).
• By 4 weeks, rhBMP-2 treated bone reached intact bone biomechanical levels, while controls reached only ~45%.

Conclusions:

• A single application of rhBMP-2 significantly enhances long-bone osteotomy healing in a rabbit model.
• rhBMP-2 treated osteotomies healed 33% faster than untreated ones.
• These findings support further investigation of rhBMP-2 for surgical fracture management.