The scaphoid is one of the eight small carpal bones in the wrist, located on the thumb side. This bone is frequently fractured, often resulting from a fall onto an outstretched hand, especially in younger, active adults. The scaphoid’s unique anatomy makes its healing process challenging compared to other bones. It receives most of its blood supply from vessels entering the distal end, requiring blood flow to travel backward toward the proximal pole (the area closest to the forearm). A fracture, particularly in the middle or proximal third, can severely disrupt this tenuous blood supply. Therefore, treatment for a scaphoid fracture varies greatly based on the severity and location of the break.
Initial Assessment and Accurate Diagnosis
Diagnosing a scaphoid fracture can be difficult because symptoms often mimic a simple wrist sprain. Following an injury, a physical examination typically reveals tenderness in the anatomical snuffbox, the triangular depression at the base of the thumb. Pain may also be present when pressure is applied to the scaphoid tubercle or when the thumb is axially compressed.
Initial imaging involves standard X-rays of the wrist, but specialized scaphoid views are necessary. Even with these specialized views, a scaphoid fracture can be “occult,” meaning it is not visible on the initial X-rays. If a fracture is strongly suspected based on the physical exam despite negative X-rays, advanced imaging is required.
A Magnetic Resonance Imaging (MRI) scan is frequently the preferred next step, as it is highly sensitive for detecting occult fractures by showing bone marrow edema. A Computed Tomography (CT) scan is an acceptable alternative that provides superior detail of the bone structure. This detail is helpful for confirming the fracture pattern, measuring displacement, and planning for surgery. Swift diagnosis is important because a delay in treatment increases the risk of complications.
Non-Surgical Treatment Options
Non-surgical treatment is the standard approach for stable and non-displaced scaphoid fractures, where bone fragments have not shifted out of alignment. This conservative management relies on strict immobilization using a specialized fiberglass or plaster cast called a thumb spica cast.
The thumb spica cast typically extends from below the elbow, including the wrist and the thumb, effectively immobilizing the scaphoid bone and preventing movement that could disrupt healing. For fractures closer to the forearm, a long-arm cast extending above the elbow may be used initially to restrict forearm rotation. The typical duration for casting is long, often ranging from 6 to 12 weeks or more.
The fracture location significantly impacts healing time due to variations in blood supply. Distal third fractures (closest to the fingers) heal fastest, while those in the middle third, or “waist,” take longer. Proximal pole fractures (closest to the forearm) have the longest healing times, sometimes requiring 12 to 23 weeks or more. Regular follow-up X-rays or CT scans are necessary throughout the immobilization period to monitor the fracture site and confirm successful union.
Surgical Intervention Techniques
Surgical intervention is indicated for scaphoid fractures that are displaced, unstable, or located in the proximal pole, where the risk of nonunion is higher. Surgery may also be recommended for active individuals who wish to accelerate their return to activities. The primary goal of any surgical technique is to achieve strong compression across the fracture site to promote bone healing.
Percutaneous screw fixation is a minimally invasive technique often used for acute, non-displaced fractures already in good position. This procedure involves inserting a specialized headless compression screw through a small incision, guided by fluoroscopy (real-time X-ray imaging). The screw spans the fracture line, compressing the fragments and providing internal stability while minimizing soft tissue disruption.
For fractures that are displaced, malaligned, or have failed to heal (nonunion), Open Reduction and Internal Fixation (ORIF) is necessary. This involves making a larger incision to visualize the fracture, manually realign the fragments (reduction), and then secure them with a compression screw. The surgeon approaches the scaphoid from the palm side (volar) or the back of the wrist (dorsal), depending on the fracture pattern.
In cases of established nonunion or bone loss, a bone graft is often required to fill the gap and stimulate healing. A non-vascularized bone graft, often taken from the patient’s forearm, acts as a scaffold for new bone growth. For fractures with compromised blood supply, especially those at the proximal pole or with avascular necrosis, a vascularized bone graft is used. This graft includes its own attached blood vessel to ensure immediate blood flow to the fracture site.
Recovery Timeline and Addressing Potential Complications
The post-treatment phase, following casting or surgery, focuses on restoring the full function of the wrist and hand. Once imaging confirms bone union, the patient begins a structured physical or occupational therapy program. This rehabilitation is necessary for regaining the range of motion and strength lost during immobilization.
Initial therapy focuses on gentle active range of motion exercises for the wrist, forearm, and thumb. Strengthening exercises, such as grip work, are progressively introduced as healing advances. The typical timeline for a return to light work is around 8 to 12 weeks after treatment. However, athletes and those performing heavy manual labor may need to avoid full activity for three to six months.
Two complications specific to scaphoid fractures are nonunion and avascular necrosis (AVN). Nonunion is the failure of the bone to heal, often occurring if diagnosis was delayed or blood supply was poor. AVN is the death of bone tissue due to a complete loss of blood supply, a risk highest for proximal pole fractures.
Both nonunion and AVN can lead to chronic pain and, eventually, a progressive form of wrist arthritis called Scaphoid Non-union Advanced Collapse (SNAC wrist). Nonunion is typically managed with ORIF and a bone graft. AVN, if detected early, may require a vascularized bone graft to restore blood flow. Smoking is a known factor that impairs bone healing and increases the risk of these complications.