What happens if a needle hits a bone? Understanding the risks

While it's a common fear during injections, hitting a bone with a needle is a relatively harmless event in most cases. This article provides an authoritative overview of exactly what happens if a needle hits a bone and offers expert guidance on what to expect and what steps to take.

Quick Summary

Hitting a bone with a needle typically causes a sudden, sharp, but momentary pain as the needle contacts the periosteum, the nerve-rich tissue covering the bone. A healthcare professional will simply withdraw the needle slightly and continue the injection, as there is usually no lasting damage. The primary risks are pain and, in rare instances, needle breakage, which require different courses of action.

Key Points

• Normal Sensation: Hitting bone causes a sharp, momentary pain due to the needle contacting the periosteum, the sensitive membrane covering the bone.

• Minimal Damage: Standard needles are not strong enough to cause lasting damage to the bone itself.

• Healthcare Provider Action: A trained professional will immediately pull back the needle slightly and continue the injection in the correct muscle tissue.

• Distinguishing Pain: Nerve contact causes a radiating, electric-shock pain, which is different from the sharp, localized pain of hitting bone.

• Serious Risks Are Rare: While needle breakage is a possibility, it is extremely rare with modern medical procedures and equipment.

• Little Effect on Medication: As long as the needle is properly repositioned, the effectiveness of the medication is not compromised.

The immediate sensation and medical response

When a needle, particularly during an intramuscular (IM) injection, encounters a bone, the sensation can be startling and uncomfortable. The bone itself has very few nerve endings and is not the source of the pain. The sharp pain is caused by the needle tip contacting the periosteum, the thin, highly sensitive membrane that covers the bone. This is a normal protective response of the body.

What a healthcare provider does

A trained healthcare provider will notice the change in resistance immediately. Instead of continuing to push against the hard surface, they will take a simple, swift action: they will pull the needle back a slight amount, reposition it slightly, and then proceed with the injection. This maneuver is standard procedure and ensures the medication is delivered into the muscle tissue as intended, rather than against the bone.

Are there any serious complications?

For most routine injections, serious complications from a needle hitting a bone are extremely rare. The main risk factors are related to the needle itself or the reaction of the patient.

Needle-related issues

• Needle breakage: A low-risk but serious complication is if the needle were to break during the procedure. Modern, sterile needles are designed to be quite strong and flexible, and this is highly uncommon, especially with proper technique. However, if it were to occur, a fragment of the needle could remain in the body, requiring medical intervention.
• Needle length: The wrong needle length for a patient's size or the injection site can increase the risk of hitting bone. This is why proper assessment and landmarking are crucial for medical professionals.

Infection risk

While hitting bone does not automatically cause infection, any break in the skin has the potential for bacteria to enter. For this reason, all injections must be performed using sterile techniques. Infections like osteomyelitis (bone infection) are extremely rare in this context and typically associated with repeated non-sterile injections by drug users, not standard medical procedures.

Differentiating between hitting bone and hitting a nerve

It's important to distinguish the sensation of hitting bone from the more concerning event of hitting a nerve. The signs and sensations are distinctly different.

Comparison Table: Hitting Bone vs. Hitting a Nerve

Feature	Hitting a Bone	Hitting a Nerve
Sensation	Sharp, immediate, but momentary pain.	Electric shock-like pain, tingling, or numbness radiating down the limb.
Location of Pain	Localized to the immediate injection site.	Radiates along the path of the nerve.
Effect on Injection	Needle stops abruptly, and sensation ceases once withdrawn slightly.	Causes a sudden, involuntary jerking motion or intense, prolonged pain.
Long-Term Issues	Typically none.	Can cause temporary or, in rare cases, permanent nerve damage.

What to do if you suspect a problem

If you are receiving an injection and experience unusual or radiating pain, it is important to communicate this clearly and calmly to the healthcare provider. They are trained to assess the situation and respond appropriately.

For the patient

• Speak up: If you feel a sharp jolt of pain that travels down your arm or leg, tell the provider immediately. This is a key indicator of potential nerve contact. The sensation of hitting bone will subside quickly, while nerve pain will be more intense and travel.
• Stay calm: Your provider is trained to handle these situations. Remaining calm helps them assess the situation quickly and take corrective action.

For the provider

• Withdraw immediately: If nerve contact is suspected, the needle should be withdrawn completely, and the injection should not be administered.
• Reassess: The provider will need to re-landmark the injection site and may need to use a new, sterile needle to try again in a different location.

Can it affect the effectiveness of the medication?

For a typical intramuscular injection, hitting bone and then repositioning the needle will not impact the effectiveness of the medication. The injection site is still the same muscle tissue, just a slightly different spot within it. However, if the needle were too short from the start, the medication could be injected subcutaneously (into the fat layer) rather than intramuscularly. This can affect the absorption rate, but is unrelated to actually hitting the bone.

Conclusion

While a frightening prospect, what happens if a needle hits a bone? is most often a minor, temporary event characterized by a sharp, localized pain. For trained healthcare professionals, it is a routine issue to resolve by simply repositioning the needle. The bone is not harmed, and for standard injections, the risks are minimal. Being aware of the difference between the sensation of hitting bone and hitting a nerve is key, and communicating with your provider is the best course of action if you feel any persistent or radiating pain. It's a testament to the safety and precision of modern medical procedures that such an event rarely leads to serious health consequences.

American Academy of Orthopaedic Surgeons

Frequently Asked Questions

Does hitting a bone with a needle hurt?

Yes, it can cause a sudden, sharp, and intense but brief pain. This is not from the bone itself, but from the needle's contact with the periosteum, the thin, nerve-rich covering of the bone.

Can an injection needle break a bone?

No, a standard injection needle is not capable of breaking a bone. It may cause temporary pain upon contact, but it is not strong enough to cause a fracture or other damage.

What is the difference between hitting a bone and a nerve with a needle?

Hitting a bone causes a sharp, localized, and momentary pain. Hitting a nerve typically causes a longer-lasting, more intense, and radiating 'electric-shock' or tingling sensation down the limb.

What should I do if I think the needle hit my bone?

If a healthcare provider is giving the injection, they will feel the bone contact and make a swift, minor adjustment. The pain should subside almost immediately. You should tell them if you feel a pain that travels or persists, as this may indicate nerve contact.

Is it dangerous if a needle hits a bone?

In a sterile, clinical setting, it is not considered dangerous. The most common outcome is a moment of discomfort. The risk of serious complications like infection is very low.

Can hitting a bone during an injection cause long-term problems?

For routine injections performed by a professional, hitting a bone and correcting the needle position does not cause any long-term problems. The pain and discomfort are temporary.

Why do dentists give injections that hit bone?

In some dental procedures, injecting a local anesthetic near the bone is an intentional and necessary part of the procedure. Dentists are trained to do this safely and will warn the patient, as the periosteum is sensitive.