What type of suture and technique is used for radial nerve repair damaged by a radial fracture and how many points should the nerve be sutured?

Radial Nerve Repair Following Radial Fracture

Direct Answer

For radial nerve repair damaged by radial fracture, use 9/0 nylon monofilament suture with interrupted epineural technique, placing 4-6 sutures circumferentially around the nerve to achieve adequate coaptation strength while minimizing tissue trauma.

Suture Material Selection

9/0 (0.3 metric) nylon monofilament is the optimal suture gauge for radial nerve repair. 1

• This gauge provides the highest force resistance before gap formation at the repair site compared to other suture sizes 1
• Finer 10/0 sutures snap at lower forces, while thicker 8/0 sutures are less consistent and pull out of nerve tissue more readily 1
• For conduit-assisted repairs, 8/0 suture at the nerve-conduit junction combined with 9/0 at the coaptation site can reduce inflammation while maintaining adequate tensile strength 2

Surgical Technique

Use interrupted epineural suture technique as the standard approach for radial nerve repair. 1

• Place sutures through the epineurium only, avoiding fascicular penetration to minimize intraneural scarring 1
• Achieve tension-free coaptation of nerve ends with minimal gap formation 1
• When nerve gap exists requiring grafting, fascicular grafting is the alternative to direct suture, though outcomes are inferior (only 38.1% useful motor recovery with grafting versus better results with direct repair) 3

Number of Sutures

Place 4-6 interrupted epineural sutures circumferentially around the nerve. 2, 1

• Increasing the number of sutures significantly increases maximum failure load regardless of suture caliber 2
• Distribute sutures evenly around the nerve circumference to prevent rotation and ensure proper fascicular alignment 1
• More sutures provide greater tensile strength, but balance this against increased tissue trauma and inflammation 2

Critical Surgical Considerations for Radial Nerve in Humeral Fractures

Open humeral shaft fractures with radial nerve palsy require immediate surgical exploration, as 64% have nerve laceration or entrapment between fracture fragments. 4

• Equal incidence of nerve injury occurs across all open fracture types (I, II, and III) 4
• Both primary and secondary epineural repair provide satisfactory functional return 4
• Rigid fracture fixation is mandatory when performing nerve repair 4

Preserve the radial nerve's blood supply by maintaining its attachment to the triceps muscle during dissection. 5

• The radial nerve receives vascular supply from deep brachial artery branches in close relation to the triceps 5
• Release only the anterolateral side of the nerve, leaving it attached posteriorly to triceps muscle 5
• Posterior retraction technique reduces iatrogenic injury risk from 26% to 1.6% 5

Timing and Prognosis

Perform repair as early as possible, as pre-operative delay significantly influences outcomes. 3

• Average interval between injury and repair in one series was 6.0 months (range 1-19 months), with shorter delays yielding better results 3
• Primary repair achieves useful motor recovery in 65% of cases overall 3
• Associated lesions are the critical factor determining final functional restoration 3

Common Pitfalls to Avoid

• Do not use 8/0 suture alone - it pulls out of nerve tissue inconsistently 1
• Do not use 10/0 suture - it snaps at insufficient forces 1
• Do not assume closed fractures with nerve palsy require exploration - these can be observed, unlike open fractures 4
• Do not perform anterior dissection and retraction - this compromises vascular supply and increases iatrogenic injury risk 5
• Do not delay exploration in open fractures - 64% have complete nerve disruption requiring repair 4