“It Depends…”
That may be the most annoying answer you can ever receive when asking someone a question. Although it may be true, without a willingness to discuss the nuance of the situation, that answer only leads to more confusion and frustration.
So how long does it take for the human body to heal? Well, “it depends” on a number of factors. Not all tissues are created equally. Ligaments heal differently than bones, and nerves heal differently than skin. These biological processes take varying amounts of time, but it is incredibly important as a healthcare consumer to have a basic understanding of tissue healing so that you can make wise decisions about what your body needs. How will you know if a practitioner is telling you the truth? Maybe your “herniated disc” will take 6 months to “heal” – or maybe IT WON’T. How will you know if you’re on the right track? Let’s start with a basic understanding of some tissue healing principles:
How long a tissue takes to heal is dependent on a number of factors such as (Source):
- Degree of injury (Ex: partial vs. complete ligament tear)
- Age
- Genetic make-up
- The individual’s body composition (obesity)
- Lifestyle habits – smoking, nutrition, aerobic conditioning, etc.
- Availability of blood supply
- Immobilization status
- Presence of infection
- Stress
- Hormonal status (Ex: diabetes, thyroid dysfunction, post-menopause, etc.)
- Substance abuse (alcohol, recreational drugs, prescription drugs)
- Medication
Thus, the tissue-specific timelines are listed below as a range rather than a strict amount of time as the exact amount of time is largely dependent on the factors listed above. As you can see, timelines vary widely. The fastest healing tissues in the body are the cornea and cheek/tongue, which heal in as little as 24-36 hours, compared to nerve tissue which regenerates at 2-5 mm/day (months to years for complete healing depending on location).
I’m not going to take a deep dive into the science behind why each tissue heals in a unique way – years of research have gone into understanding this topic and it can’t be summarized briefly. However, I am going to leave you with 6 things I want you to know about tissue healing and why you need to understand this topic:
- Some tissues have limited to no healing capacity. Based on some of the factors listed above, some tissues may not be able to heal at all. Examples of this include severe nerve injuries, some high grade articular cartilage injuries, and some complete tendon ruptures.
- There are some factors associated with tissue healing that are out of your control. The factors listed above are known to contribute to healing, but some of them are not modifiable. You can’t change your age or genetic makeup or the severity of your injury, and these are some of the most important factors in tissue healing.
- If a tissue isn’t healed within 12 weeks, complete healing is unlikely to occur without significant medical intervention. Just by looking at the chart above, most tissue should heal within 12 weeks, with the exception of high grade nerve and articular cartilage injuries. So what if you’re still having pain, stiffness, and inability to use the affected tissue 12 weeks later? This is no longer a healing problem – this is a nervous system problem. More to come on this topic.
- The timelines for healing and pain relief are not the same. Pain relief can happen relatively quickly despite a lack of tissue healing. The opposite can also be true – a tissue can be completely healed, but pain may be the same or worse than it was when the tissue was initially injured. So what does this mean? You can’t let how you’re feeling influence your thoughts on healing. Just because you’re still having pain doesn’t mean you haven’t “healed,” and just because your pain is gone doesn’t mean your tissue is fully healed. Pain and tissue healing are not solely dependent on one another. Sadly, it’s more complicated than that.
- Complete healing is not necessary in order to restore function. In fact, in many cases, normal function can be restored without complete healing. In other words, what your tissue looks like under a microscope or on x-ray/MRI/CT scan does not always correlate with your ability to use your injured body part. For instance, many patients with complete rotator cuff tears are able to return to their previous activities with full use of their arm, despite the fact that their rotator cuff never fully “heals.”
- Just because something hurts or doesn’t move well does not necessarily mean there is damaged tissue that needs to “heal.” This is why imaging findings can be frustrating and misleading. Abnormalities on x-ray or MRI are often assumed to be the direct and primary cause of pain or disability, but without a reference point (previous imaging study before the onset of these symptoms), it is impossible to prove that these abnormalities are directly related to the symptoms you are currently experiencing. In fact, treatment of these abnormalities can often be ineffective because issues like herniated discs, degenerative disc disease, labral tears, and rotator cuff tears are normal consequences of aging and activity.
So how do you know if you’re making the right decisions in regards to how you’re managing your painful situation? Maybe you just need to give it more time to rest? Or maybe you just need to stick with what you’ve been doing as your practitioner tells you that it’s just a matter of time and it could takes months or years before you are “normal” again. I’ll address those questions directly in the next 2 parts of this series.
Coming up next, Part 2 of this series will discuss how long to wait before seeking medical care for a new onset of pain or a new injury, and what are the benefits and consequences of “watchful waiting” compared to seeking care immediately.