Radial Nerve Palsy: Recovery Timeline and Full Therapy
Expected Recovery Timeline
Most radial nerve palsies associated with humeral shaft fractures recover spontaneously within 3–6 months, with initial signs of recovery appearing between 2 weeks and 6 months post-injury. 1, 2, 3
Timeline Based on Trauma Energy
Low-energy trauma (simple fractures): Initial recovery signs appear at a mean of 3.2 weeks (range 1–8 weeks), with full recovery averaging 14 weeks. 1
High-energy trauma (complex fractures): Initial recovery signs appear at a mean of 12 weeks (range 3–23 weeks), with full recovery averaging 26 weeks in cases where the nerve remains intact or entrapped. 1
Spontaneous recovery rate with nonsurgical management: 77.2% of patients recover nerve function without surgery. 2
Critical Decision Points
The 3-month mark is the key decision point for surgical exploration if no recovery signs are evident. 3 Initial signs of nerve recovery may appear anywhere between 2 weeks and 6 months, so observation during this window is appropriate for closed injuries. 3
Full Therapy Algorithm
Immediate Assessment (0–3 Weeks)
Early surgical exploration within 3 weeks is indicated for:
- Open fractures with radial nerve palsy 3
- Ultrasonography showing severe nerve damage or complete transection 3
- Penetrating trauma or sharp lacerations 4
Early surgical exploration yields an 89.8% recovery rate, significantly higher than the 77.2% spontaneous recovery rate with expectant management or the 68.1% recovery rate with delayed exploration beyond 8 weeks. 2
Observation Period (3 Weeks to 6 Months)
For closed fractures without ultrasonographic evidence of complete nerve disruption, expectant management is appropriate during this window. 1, 3
- Monitor for initial signs of recovery: return of brachioradialis function, wrist extension, or finger extension 3
- Serial clinical examinations every 4–6 weeks 3
- Electromyography (EMG) at 3 months if no clinical recovery 3
- Ultrasonography to assess nerve continuity 3
Low-energy fractures uniformly recover and do not require primary surgical exploration. 1
Surgical Exploration (3–6 Months)
If no recovery signs appear by 3–6 months, surgical exploration is indicated. 3 The decision is based on:
- Patient age (younger patients are better candidates for nerve grafting) 3
- EMG findings showing denervation without reinnervation 3
- Ultrasonography demonstrating nerve discontinuity 3
Nerve grafting should be performed before 6 months in younger patients if local conditions are suitable. 3
Nerve Transfers (6–10 Months)
Nerve transfers can be offered up to 10 months post-injury when performed by an experienced team. 3 This option is particularly valuable when:
- Nerve grafting is not feasible due to local tissue conditions 3
- The patient is beyond the optimal window for autografting 3
- Satisfactory results can still be achieved with nerve transfers 3
Tendon Transfers (Beyond 10–12 Months)
Tendon transfers are the gold standard treatment and the only option available beyond 10–12 months. 3, 5
Common donor tendons include:
- Pronator teres (for wrist extension) 5
- Wrist flexors (for finger extension) 5
- Finger flexors (for thumb extension) 5
Tendon transfers provide reliable and fast results, with good outcomes reported for most methods, as they are positional transfers not requiring significant power. 5
Prognostic Factors
Favorable Prognosis
- Low-energy trauma: 100% recovery rate in published series 1
- Intact or entrapped nerve at exploration: High recovery rate even in high-energy trauma 1
- Early surgical exploration (within 3 weeks): 89.8% recovery rate 2
Poor Prognosis
- High-energy trauma with neurotmesis: Patients with severely damaged nerves fail to recover even with microsurgical reconstruction. 1
- Delayed exploration (beyond 8 weeks): Only 68.1% recovery rate 2
- Complete nerve transection: Requires immediate surgical repair 4
Common Pitfalls to Avoid
Do not perform unnecessary early exploration in low-energy closed fractures, as these uniformly recover spontaneously and surgery adds morbidity without benefit. 1
Do not delay exploration beyond 6 months in younger patients if no recovery signs are present, as nerve grafting becomes less effective after this window. 3
Do not wait beyond 10–12 months for any reconstructive procedure, as tendon transfers become the only viable option and nerve-based procedures are no longer effective. 3
In high-energy fractures, inform patients early of the poor prognosis (potential for permanent deficit) and the likely need for tendon transfers, as neurotmesis or severe contusion must be expected. 1