When should a dorsal slab be used in volar distal radius (distal radius) plating, particularly in patients with a high risk of dorsal displacement or instability, such as older adults with osteoporosis and comminuted or intra-articular fractures?

When to Use a Dorsal Slab in Volar Distal Radius Plating

You should not routinely use a dorsal slab when performing volar locking plate fixation for distal radius fractures, as volar plating provides adequate stability for most fracture patterns, including those in elderly patients with osteoporosis and comminuted fractures.

Primary Fixation Strategy

The AAOS guidelines provide strong evidence that volar locking plates are sufficient for stabilizing complete articular and unstable distal radius fractures without requiring supplemental dorsal splinting 1. The volar approach has become the standard because:

• Volar locked plating leads to earlier functional recovery at 3 months compared to other fixation methods 1
• No significant difference exists in long-term radiographic or patient-reported outcomes between different fixation techniques 1
• The construct provides adequate stability through fixed-angle locking screws that resist dorsal collapse 2

Specific Indications Where Dorsal Slab May Be Considered

While not explicitly addressed in current AAOS guidelines, clinical scenarios where supplemental dorsal splinting after volar plating might be warranted include:

Severe Dorsal Comminution

• When there is extensive dorsal cortical comminution that cannot be adequately buttressed from the volar approach alone 3, 4
• Dorsal impaction injuries where the volar plate cannot directly support the dorsal articular fragments 4

High-Risk Patient Factors

• Patients with severe osteoporosis where screw purchase is questionable 2
• High-energy injury mechanisms in elderly patients, which are associated with increased risk of height collapse 2
• Older age (the collapse group in one study had mean age considerations) combined with poor bone quality 2

Important Caveats

The evidence does not support routine dorsal splinting after volar plating. The guidelines indicate that:

• Volar locked plates provide sufficient stability even in geriatric patients with osteoporosis 1
• Post-operative immobilization protocols are not well-defined in the guidelines, but early motion is generally favored 1
• If you're considering a dorsal slab because of concerns about stability, you may actually need dorsal plating rather than volar plating with a slab 3, 4

When Dorsal Plating (Not Slab) Is Actually Indicated

If you're concerned enough about dorsal instability to consider a dorsal slab, consider whether dorsal plating is more appropriate:

• Dorsally comminuted fractures requiring direct buttressing 3, 4
• Dorsal impaction injuries where anatomic reduction requires direct visualization 4
• Modern low-profile dorsal plates have comparable outcomes to volar plates when used appropriately 3, 5
• Use of an extensor retinaculum flap minimizes tendon complications with dorsal plating 6

Practical Algorithm

1. Assess fracture pattern on CT if complex - determine if dorsal comminution is severe 4
2. If volar plating provides adequate reduction and fixation - no dorsal slab needed 1
3. If concerned about dorsal fragment support - consider dorsal plating instead of volar plating with slab 3, 4
4. Ensure longest possible distal screws just beneath subchondral bone to prevent collapse 2
5. Early active motion regardless of fixation method 1

The key pitfall is using a dorsal slab as a "safety net" for inadequate fixation - if your volar plate construct requires supplemental external support, reconsider whether volar plating alone is the appropriate surgical strategy for that specific fracture pattern.