Scaphoid Open Reduction and Internal Fixation Through Dorsal Approach

Abstract 

Scaphoid fractures are the most common carpal injury and have a high complication propensity. In particular, the unique blood supply of the scaphoid leads to an increased rate of avascular necrosis, while the geometry of the scaphoid causes relatively high rates of nonunion.

Among operative approaches, percutaneous and open reduction with internal fixation (ORIF) may both be considered, with ORIF being preferred for displaced, comminuted, proximal pole and nonunion/delayed healing fractures. With internal fixation, a dorsal or volar approach can be undertaken based on fracture alignment.

Here, we discuss the case of a proximal pole scaphoid fracture repaired with ORIF via a dorsal approach. After dissection through the joint capsule and exposure of the base of the scaphoid, a headless compression screw is placed anterograde in line with the thumb in all planes. This procedure provides increased stability and improved rate of the union in correlation with the accuracy of intraoperative reduction, leading to improved outcomes for surgical candidates over more conservative approaches. 

Case Overview

Background

Scaphoid fractures are a common traumatic injury, accounting for about 15% of all acute wrist injuries.¹ Young, active males are the most frequently affected demographic with falling on an outstretched hand being the most common etiology.² 

The scaphoid bone is prone to chronic sequelae if not appropriately managed, most notably nonunion as well as avascular necrosis (AVN), which can contribute to both chronic pain and reduced function of the wrist joint.³ Of note, the unique blood supply from the dorsal carpal branch of the radial artery, which provides retrograde perfusion to the scaphoid and is prone to damage during scaphoid fracture, predisposes to AVN of the proximal pole of the scaphoid.³ 

A degree of uncertainty exists in the ideal management algorithm for scaphoid fractures, with surgeon opinions on ideal operative approach varying in regard to fracture location, instability, hardware use, and more.⁴

Focused History of the Patient

History should focus on the mechanism of injury and time since the injury in order to guide treatment decision making. Additional information relevant to surgical candidacy should be gathered including past medical/surgical history, current medical conditions, current medications, and smoking history. 

Physical Exam

Pertinent findings on physical exam include: 

• Inspection of the wrist for the severity of the swelling, gross deformity, and erythema/ecchymosis.
• Evaluation of any wounds about the wrist.
• Assess pain with gentle passive manipulation of the wrist and tenderness within the anatomic snuffbox.

Imaging

Confirmatory imaging is most often achieved with plain radiographs including anteroposterior, lateral, and oblique views of the wrist. Special radiographs including a scaphoid view taken posteroanteriorly with the wrist in 30-degrees of ulnar deviation may occasionally be of value. Computed tomography (CT) may be helpful for preoperatively planning to assess fracture characteristics. Magnetic resonance imaging (MRI), while not routinely indicated, may be helpful if plain film radiographs are negative or inconclusive yet a high index of suspicion for scaphoid fracture exists.⁵ Imaging is also used to determine the Herbert, Mayo and/or Russe classifications. Based on the Mayo classification, 70% are middle scaphoid, 20% are distal scaphoid, and 10% are proximal scaphoid fractures.⁶ 

Natural History

Without intervention, untreated scaphoid fractures have a high rate of nonunion or malunion, increasing the likelihood of degenerative arthritis⁷, as well as AVN in up to 50% of all untreated scaphoid fractures.⁸ The likelihood of chronic complications is related to the severity of the injury, the extent of comminution and displacement, and the location of the fracture.

Options for Treatment

Treatment is predicated based on fracture alignment, fracture characteristics and location, and patient characteristics and expectations. 

Non-operative treatment with cast immobilization is indicated for acute and non-displaced fracturs of the scaphoid. 

Rationale for Treatment

Operative treatment for isolated scaphoid fractures is indicated for displaced or comminuted fractures, proximal pole fractures, and fractures with delayed diagnosis or healing. Percutaneous fixation is preferred if the displacement of the fracture is minimal and there is no significant angulation or deformity. Open reduction with internal fixation (ORIF) is indicated in cases with more severe displacement, proximal pole fractures, humpback deformity of 15 degrees or more, comminuted fractures, or fractures with delayed diagnosis, healing, or nonunion.^9, 10 While both the dorsal and volar approaches to the surgery are reasonable, distal and middle fractures are more commonly operated on via a volar approach, while proximal pole fractures are more commonly approached dorsally to allow ease of screw placement.⁶

Discussion

Clinical management of scaphoid fractures varies based on the severity of the injury and findings on imaging. Over time, however, clinical trends have moved towards a preference for surgical intervention over conservative management as multiple studies have shown a reduction in arthritis when compared with cast immobilization.^11-13 

Proximal pole fractures of the scaphoid, as highlighted in the present case, are considered inherently unstable and prone to AVN; therefore, they require surgical intervention. In contrast, nondisplaced wrist fractures may be conservatively managed with cast immobilization. Among surgical approaches for proximal pole and unstable fractures, ORIF is preferred due to lower rates of malunion, arthrosis, and osteonecrosis when compared with the percutaneous approach.

Since its introduction in 1984, ORIF with headless compression screw fixation has become the favored surgical technique for the repair of unstable scaphoid fractures.⁹ This fixation strategy allows for internal fixation, compression, and stability while not leaving hardware prominent on the articular surface of the scaphoid. The central placement of the screw is critical to achieving a successful union and is technically easier from the dorsal approach.⁹ With adequate screw placement, successful union rates of scaphoid fractures can surpass 95%.⁹

Future considerations for operative management of scaphoid fractures include advancement in hardware options and applications—such as alternative screw types¹⁴, use of double-screw fixation¹⁵, and scaphoid plate fixation¹⁶—and improved guidelines for ideal surgical approaches to subtypes of scaphoid fractures. 

Outcomes

Measures of surgical efficacy can vary and may include:

• Rate of the successful union on imaging follow-up
• Time-to-union
• Grip strength
• Wrist mobility and range of motion
• Return to sport/activity
• Pain experienced
  

Equipment

• Headless compression screw

Disclosures

Nothing to disclose.

Statement of Consent

The patient referred to in this video article has given their informed consent to be filmed and is aware that information and images will be published online.