Why do scaphoid bones take so long to heal?

From the Guidelines

The scaphoid bone takes a long time to heal primarily due to its limited blood supply, which is a critical factor in determining the viability of the proximal pole, as evidenced by a study using dual-energy contrast-enhanced CT 1. The scaphoid receives blood mainly from vessels that enter at its distal end, meaning the proximal portion has a tenuous blood supply. This poor vascularity, especially in the proximal third of the bone, significantly slows the healing process. Some key factors contributing to the prolonged healing time of scaphoid bones include:

• Limited blood supply, particularly in the proximal third of the bone
• Constant stress during hand movements, which can disrupt the healing process
• The bone is mostly covered by cartilage, leaving few entry points for blood vessels
• Fractures of the scaphoid typically require 8-12 weeks of immobilization for proper healing, and sometimes up to 6 months for complete recovery, as supported by the assessment of proximal pole osteonecrosis using dual-energy contrast-enhanced CT 1. More severe fractures, especially those in the proximal third, may require surgical intervention with internal fixation using screws to promote healing. Without proper treatment, the limited blood supply can lead to avascular necrosis (bone death) of the proximal fragment, resulting in long-term wrist problems, highlighting the importance of early diagnosis and appropriate treatment of scaphoid fractures for optimal outcomes, as indicated by the high sensitivity and specificity of dual-energy contrast-enhanced CT in assessing osteonecrosis of the proximal pole 1.

From the Research

Scaphoid Bone Healing

The scaphoid bone takes a long time to heal due to several factors, including:

• Its unique geometry and tenuous vascular pattern, which can lead to delays in diagnosis and inadequate treatment 2, 3
• The risk of nonunion, which can be as high as 10% after surgical treatment 2
• The potential for avascular necrosis of the proximal pole, which can make treatment more challenging 4, 5

Treatment Challenges

Treatment of scaphoid fractures and nonunions can be complex, with various surgical techniques and strategies available, including:

• Open reduction and internal fixation with bone grafting 2
• Vascularized bone grafts, which have gained popularity in recent years 2, 5
• Percutaneous fixation and other newly developed fixation techniques 2

Complications and Consequences

If left untreated, scaphoid nonunions can lead to:

• Carpal collapse and degenerative arthritis 2
• Loss of motion and persistent pain 5
• Premature radiocarpal arthrosis 3 It is essential to approach diagnosis and treatment in a systematic and deliberate manner to achieve optimal results 4, 6