If you’ve been dealing with Achilles tendonitis or plantar fasciitis, you know how frustrating these conditions can be. The pain is often worse in the morning, making those first few steps out of bed feel like walking on broken glass. One of the most effective, yet underutilized, treatments for these conditions is the posterior night splint.
At Lighthouse Foot and Ankle Center, we often recommend night splints, but not necessarily in the traditional way. Wearing them overnight can be uncomfortable, which is why I personally suggest using them as a rest splint for 2 to 3 hours in the evening instead. This approach still delivers excellent results while being far more tolerable for patients.
Let’s dive into why posterior night splints work, how they help both Achilles tendonitis and plantar fasciitis, and the best way to use them for relief.
Why Are Mornings So Painful? Understanding the Root Cause
Plantar Fasciitis:
The plantar fascia is a thick, fibrous band of tissue that runs along the bottom of the foot, connecting the heel to the toes.
Overnight, as you sleep, your foot naturally relaxes into a pointed position (plantar flexion). This causes the plantar fascia to tighten and shorten.
When you take your first steps in the morning, the sudden stretch on a stiff plantar fascia leads to micro-tears and sharp pain in the heel.
Achilles Tendonitis:
The Achilles tendon connects the calf muscles to the heel bone and plays a crucial role in walking, running, and jumping.
When the foot is relaxed in a plantarflexed (pointed) position during sleep, the Achilles tendon shortens overnight.
The first steps in the morning cause an abrupt stretch, leading to stiffness, pain, and inflammation.
How Posterior Night Splints Help
A posterior night splint keeps the foot in a dorsiflexed position (toes pointing upward) rather than letting it relax into plantar flexion. This gently stretches the plantar fascia and Achilles tendon throughout the night, preventing the tightening that leads to morning pain.
The Science Behind Night Splints: How They Work
1. Maintaining a Gentle, Prolonged Stretch
Unlike daytime stretching, which is brief, night splints provide hours of sustained stretching to the plantar fascia and Achilles tendon.
This prevents the overnight contracture that leads to intense morning pain.
Over time, this gradually improves flexibility and reduces inflammation.
2. Reducing Micro-Tears in the Morning
With regular use, the plantar fascia and Achilles tendon become less stiff overnight, reducing the risk of micro-tears when you take your first steps.
This means less pain, better mobility, and a faster recovery.
3. Preventing the Cycle of Inflammation
When your fascia or tendon tears slightly each morning, your body responds with inflammation, worsening the condition.
Night splints help break this cycle by preventing excessive strain during the first steps of the day.
Why I Recommend Using Night Splints as Rest Splints Instead of Overnight Use
While night splints are highly effective, they can be difficult to sleep with. Many patients struggle with discomfort, bulkiness, and disturbed sleep. Instead of wearing them overnight, I suggest:
Wearing the splint for 2 to 3 hours while resting in the evening (such as while watching TV or reading).
If you experience severe morning stiffness, try to wear it for the first 1-2 hours of sleep before taking it off.
Use it as a rest splint throughout the day when sitting for 30 minutes or longer.
By modifying how you use the splint, you still achieve the therapeutic benefits without the discomfort of wearing it all night.
How to Use a Posterior Night Splint Effectively
1️. Start Gradually: Begin with 30-60 minutes per evening, gradually increasing to 2-3 hours.
2️. Adjust the Angle: Some splints allow for adjustable dorsiflexion. Start at a mild angle and slowly increase as tolerated.
3️. Pair with Other Treatments: Night splints work best when combined with:
Daily calf and plantar fascia stretches
Custom orthotics for arch support
Shockwave or laser therapy for stubborn cases
Ice rolling massage for inflammation control
Be Consistent: Like any treatment, regular use is key to seeing results.
What to Expect: Timeline for Improvement
First Few Days: Your foot may feel a bit sore after use—this is normal as the tissue is gradually lengthened.
2-4 Weeks: Morning pain should begin to decrease in intensity and duration
6+ Weeks: You should notice a significant improvement in flexibility, reduced morning pain, and easier mobility.
If symptoms persist beyond 6-8 weeks despite using a night splint, further intervention may be needed (such as shockwave therapy or custom orthotics).
Who Should Use a Posterior Night Splint?
Anyone with chronic morning heel pain from plantar fasciitis
Athletes or active individuals with tight Achilles tendons
People recovering from Achilles tendonitis or tendinosis
Patients with recurring plantar fasciitis who want to prevent flare-ups
Those who struggle with tight calves despite daily stretching
🚫 Who Should Avoid Night Splints?
People with severe nerve conditions affecting foot sensation
Those with circulatory issues or diabetes (unless advised by a podiatrist)
If the splint causes significant discomfort, it may need to be adjusted or replaced with a different model
Final Thoughts: Small Changes, Big Results
If Achilles tendonitis or plantar fasciitis is making your mornings miserable, a posterior night splint is one of the most effective tools to break the pain cycle.
💡 Remember: You don’t have to wear it all night to benefit! 2-3 hours as a rest splint can still deliver excellent results—without the sleep disruptions.
📞 Ready to Get Rid of Morning Foot Pain?
If you’re struggling with persistent heel or Achilles pain, let’s create a treatment plan that works for you.
✅ Schedule an appointment today at Lighthouse Foot and Ankle Center to find the right night splint and additional therapies to get you back to pain-free movement!