Experiencing heel pain when lying on your back can be uncomfortable. This discomfort, often felt during rest, can disrupt sleep and daily comfort. This common heel pain stems from various treatable causes. Understanding heel anatomy and how conditions manifest under pressure can help address the issue.
Understanding Heel Anatomy
The heel is a complex structure designed to absorb impact and support body weight. The calcaneus, the largest bone in the foot, forms the heel’s prominent back part. Beneath the calcaneus lies the plantar fat pad, a specialized cushioning system. This fat pad acts as a natural shock absorber, protecting bone and surrounding tissues.
Soft tissues and nerves traverse the heel area. The plantar fascia, a thick band of tissue, runs along the bottom of the foot from the heel bone to the toes, supporting the arch. Nerves such as the tibial nerve and its branches, including Baxter’s nerve, pass through this region, providing sensation to the foot. The Achilles tendon connects the calf muscles to the back of the heel bone, enabling movement. Small fluid-filled sacs called bursae cushion joints and reduce friction.
Conditions Causing Heel Pain When Lying Down
Heel pain when lying on your back often relates to conditions exacerbated by sustained pressure or foot positioning during rest.
Fat Pad Atrophy
One common cause is fat pad atrophy, where the natural cushioning under the heel thins or deteriorates. This loss of padding exposes the calcaneus to increased pressure when lying supine, causing pain that feels like walking on bone or a persistent bruise. Aging is a primary factor, as fatty tissue naturally reduces over time; repetitive stress or certain medical conditions can also contribute.
Nerve Entrapment
Nerve entrapment, such as Baxter’s nerve entrapment or tarsal tunnel syndrome, can cause heel discomfort at rest. In these conditions, nerves in the heel or ankle become compressed or irritated. Lying on the back can apply sustained pressure to these already compromised nerves, leading to symptoms like shooting pain, tingling, or numbness in the heel and foot. Discomfort might intensify as the nerve remains compressed.
Pressure Injuries
Pressure-related pain or pressure injuries can occur, particularly in individuals with reduced mobility. Prolonged pressure on the heel, especially against a firm mattress, can restrict blood flow to the skin and underlying tissues. This sustained compression can lead to localized pain and, in severe cases, skin breakdown or sores. Lack of movement during sleep can make the heel vulnerable to injury.
Bursitis
Bursitis, an inflammation of the bursae, can contribute to heel pain when lying down. These small fluid-filled sacs cushion tendons and bones; direct pressure from resting on the heel can irritate an inflamed bursa. This irritation can result in a tender, bruise-like sensation at the back or bottom of the heel. Pain may be constant or worsen with direct contact.
Plantar Fasciitis
While often associated with morning pain, plantar fasciitis can cause discomfort when lying down. During rest, such as sleep, the plantar fascia and calf muscles can tighten. When the foot is positioned flat or its angle changes, this tightening can strain the inflamed tissue, leading to pain. This can be noticeable upon shifting position or getting out of bed.
Strategies for Home Relief
Several home strategies can alleviate heel pain when lying on your back.
Cushioning and Padding
Cushioning and padding are a primary approach to reduce direct heel pressure. Pillows, specialized heel protectors, or foam pads can elevate and offload the heel from the mattress. Placing a pillow under the calves can suspend the heels, preventing direct contact and distributing pressure evenly.
Adjusting Sleeping Positions
Adjusting sleeping positions can provide relief. While sleeping on the back, a pillow under the knees can maintain a slightly flexed knee position, which may reduce tension in the calf muscles and plantar fascia. For side sleepers, a pillow between the knees can maintain proper spinal alignment and relieve lower limb pressure. Some find relief by allowing their feet to hang slightly off the end of the bed, which can prevent the plantar fascia from tightening overnight.
Gentle Stretching
Gentle stretching exercises can address muscle tightness contributing to heel pain. Calf stretches, such as leaning against a wall with one leg back, can lengthen the calf muscles, which connect to the heel via the Achilles tendon. Plantar fascia stretches, like pulling the toes towards the shin or rolling the foot over a frozen water bottle, can improve arch flexibility. Performing these stretches before bed and upon waking can reduce stiffness.
Ice and Heat Therapy
Applying ice or heat can manage pain and inflammation. Ice therapy, using an ice pack or frozen water bottle rolled under the foot, can reduce inflammation and numb the painful area. Heat, applied via a heating pad or warm compress, can promote blood circulation and relax tight muscles, benefiting stiffness. Alternating between ice and heat can offer comprehensive relief.
Over-the-Counter Pain Relievers
Over-the-counter pain relievers, such as ibuprofen or naproxen, can manage acute pain and reduce inflammation. These medications provide temporary relief, allowing for more comfortable rest and participation in home remedies. Follow dosage instructions and consult a pharmacist if unsure about their use.
When to Seek Professional Guidance
While many cases of heel pain improve with home care, certain signs indicate professional medical assessment is beneficial. If heel pain persists for over two weeks despite home remedies, or worsens over time, consult a healthcare provider. Pain that significantly interferes with sleep or daily activities warrants professional attention. This persistence or escalation suggests a formal diagnosis and tailored treatment plan is needed.
Red flag symptoms requiring prompt medical evaluation include pain accompanied by numbness, tingling, or weakness in the foot. These neurological symptoms could point to nerve involvement requiring specialized intervention. Signs of infection, such as redness, swelling, warmth around the heel, or a fever, necessitate immediate medical attention to prevent complications.
Sudden onset of severe heel pain, especially following an injury, fall, or accompanied by a popping or grinding sound, indicates a potential fracture or other serious acute injury. Inability to bear weight on the affected foot or walk normally are serious indicators. Individuals with diabetes should seek medical attention for any heel pain, as foot problems can be more serious due to compromised circulation and sensation. An accurate diagnosis is important for effective treatment and preventing long-term issues.