People use their hip joints in almost every non-sedentary action, and even some sedentary ones.
The hip plays an integral part in sitting, standing, walking, running, and even wiggling our toes.
A delicate network of bones, cartilage, nerves, and many more factors make up the hip and allow us to use these valuable functions. Sometimes this delicate network can be disrupted, however.
It is possible to start feeling pain in the hip caused by several different factors – any one of the factors in the network can be disrupted by abnormalities, injury, and overuse among other things. Though the pain may be dull or severe at first, it is imperative that it is diagnosed correctly so that the treatment is as effective as possible.
Anatomy of Hip Impingement
Hip impingement is one of the most common sources of hip pain and is characterized by the pinching of the cartilage between the bones that make up the ball-and-socket joint.
This joint is surrounded by cartilage and muscles that allow the body to complete all of the tasks involved in hip movement.
The important components of hip functionality are:
- Femoral Head: the ball part of the ball-and-socket joint and the round head of the thigh bone. It fits into the acetabulum to allow for all hip, and therefore leg, movement, and even extends to movement of the toes.
- Acetabulum: the socket part of the joint which can be found in the pelvis.
- Articular cartilage: a fleshy cover for the femoral head and acetabulum that allows the bones to move without rubbing against one another.
- Labrum: attached to the articular cartilage, this type of cartilage stabilizes the joint by expanding the socket.
Causes of Hip Impingement
Hip impingement occurs most frequently in active people who are between the ages of 20 and 50. Hip impingement can occur in anyone at anytime, however. An individual does not need to be an athlete nor do they need to exercise regularly.
Athletes who frequently exercise the hip with repetitive motions, such as swimmers, runners, or dancers can also wear down the cartilage in the ball-and-socket joint as they exercise. Almost every sport involves use of the hip joint, therefore most athletes are at risk.
Additionally, a hip injury at any point in life may also contribute to hip impingement as it is possible for the cartilage or bone to heal in an abnormal position. Injuries may also interrupt the natural biomechanics of the hip and cause abnormal deterioration of the soft tissues in the hip.
People who are born with an abnormal hip structure are at a higher risk of developing hip impingement. Depending on the abnormality, the cartilage may not function as a cushion, or could be allowing the bones to rub against one another, causing discomfort. In some cases, the hip socket is formed too deep and doesn’t support the acetabulum as it should.
Types of Hip Impingement
There are three types of hip impingement which have been identified – cam impingement, pincer impingement, and combined impingement.
These are all caused by some type of bone growth that is abnormal and are classified based on the location of the bone growth.
- Cam Impingement: bone at the femoral head can grow abnormally and interfere with joint function. It does so by either pinching the cartilage, which can cause damage to it over time, or it interferes by changing the shape of the joint which therefore impacts function and range of motion.
- Pincer Impingement: when the bone of the socket grows over the cartilage, it can dig into it and cause a painful pinching sensation.
- Combined Impingement: this occurs when cam and pincer impingement occur simultaneously.
Symptoms of Hip Impingement
The most tell-tale sign of hip impingement is pain in the hip area. This pain can be constant or intermittent and can be a sharp pain or a dull ache. Some people experience pain during certain activities such as walking or sitting down, whereas others may experience chronic pain. Some patients are also able to hear a sound in the hip during certain movements resembling a popping sound.
Patients may also experience stiffness surrounding the joint, or a reduced range of motion. Weakness and soreness are also associated with hip impingement. Depending on the severity and location of the pain, some patients may also limp when walking. Given that there are several potential factors contributing to pain in the hip, it is important for doctors to be able to properly diagnose it.
Diagnosing Hip Impingement
A consultation will typically begin with an interview. Doctors will ask about previous injury or medical conditions such as osteoarthritis or hip dysplasia.
Before doing any testing doctors will ask about familial conditions that may be related to the hip, previous hip injury, and patient activity levels. In order to receive an accurate diagnosis, it is important to be as honest as possible.
Once they have gathered this information, doctors might perform several tests to determine the cause of the pain. These tests include:
- Physical examination: doctors may perform a series of tests, including watching the patient walk, observing the range of motion of the hip joint, and feeling the area for any bumps or abnormalities. Doctors may also perform passive tests, where the patient is in a relaxed position and the doctor moves the leg to determine range of motion and what movements trigger pain.
- X-Ray Imaging: this type of imaging produces a picture of the bone structure in the hip, which can allow doctors to spot abnormalities in the femoral head or acetabulum. X-Ray imaging does not show the cartilage, so if the injury is being caused by the cartilage in the joint then they may order MRI tests.
- MRI testing: these tests are able to determine the location and functionality of the articular cartilage and labrum, therefore giving doctors the ability to see if there are abnormalities or damages that are causing pain. In the case of hip impingement, MRIs are not necessary because the problem is most often caused by an abnormality in the bone.
- CT Scan: this type of scan is able to compile a 3-D image of the cartilage and muscles surrounding and inside the joint which can help to detect the source of the pain.
- Cortisone or Anesthetic Injections: sometimes a doctor will inject cortisone or an anesthetic into the cartilage of the joint to determine if this helps with pain. If pain is reduced after the injection, it is indicative of hip impingement and helps to rule out the possibility of problems with the surrounding cartilage or bone.
Hip impingement may lead to more serious conditions. Many studies have been done to determine the relationship between osteoarthritis and hip impingement. Osteoarthritis is characterized by a degradation of the joint tissue between bones.
Hip impingement is considered to be pre-arthritic, meaning that if left untreated it can lead to osteoarthritis later in life. It is important to diagnose and treat hip impingement as early as possible to prevent the development of osteoarthritis.
Undergoing certain tests and answering questions honestly can give doctors a clear idea of where the pain is coming from and how to treat it.
Treatment of Hip Impingement
The initial treatment plan usually involves rest and anti-inflammatory medication. In some cases, this will be enough to treat the injury as the body may be capable of healing itself. If these do not work, however, there are several conventional treatment options available to help treat the pain:
- Physical Therapy: this is an option that allows patients to work with a therapist to restrengthen the muscles surrounding the joint that may have deteriorated over time. Physical therapy is also useful to help increase the range of motion and improve balance on the affected hip.
- Surgery: in many cases with hip impingement, surgery becomes necessary to reduce pain. The type of surgery implemented depends on the findings of the diagnostic tests. If surgery is considered the best option, it is more than likely that doctors have found several issues and will treat more than one of them at once. For example, if there is a tear in the labrum and an abnormality in one of the bones, surgeons will operate on both during the same procedure.
There are several types of surgery that a patient may face:
- Arthroscopy: a minimally invasive procedure that uses a tiny camera to guide surgical equipment to the source of pain and correct it.
- Osteoplasty: sometimes surgeons will elect for a more invasive form of surgery that involves cutting and/or reshaping the bone where the abnormality occurs. This results in a better fit of the joint which can allow the joint to heal in a more normal state. Osteoplasty is used to correct bone abnormalities that may be causing hip impingement and has a high success rate.
- Labral Repair: if there is damage to the labrum, doctors may elect to realign the labrum by repairing damage that has occurred over time. In labral repair, the cartilage is reattached to the bone if it has detached over the course of the impingement.
Any surgical operation will come with a list of risks that must be considered alongside the benefits. The biggest risks associated with surgery are those associated with anesthesia; patients are at a risk of developing an adverse reaction to it which can lead to heart attack, pneumonia, stroke, or even death.
Patients who are elderly or have compromised immune systems are at a higher risk of these reactions. There is also a risk of developing infection with any surgery.
Regenerative Medicine and its Role in Hip Impingement Treatment
A field of medical science called regenerative medicine has gained a lot of traction lately for its effectiveness in helping to treat a myriad of conditions. This can include arthritis, tendonitis, impingement, and many more. Regenerative medicine is particularly effective when it is applied to soft tissues and is therefore a strong candidate for helping to treat hip impingement. There are two major types of regenerative therapy:
- Stem Cell Therapy: humans have stem cells all over the body, though for this procedure they are typically harvested from blood cells, bone marrow, or fat cells. This procedure involves extracting cells from the patient, processing them, and reinjecting them into the area that is causing pain. Stem cells have the ability to call to other cells in the body to help with healing and regrowth.
- Platelet-Rich Plasma (PRP) Therapy: in PRP therapy, a doctor will take the patient’s blood sample and put it into a centrifuge to separate the platelets from the plasma. Plasma in the blood contains growth factors which aid in healing throughout the body. The concentrated platelets are then injected into the pain site where they are able to use the increased growth factors to heal injury.
Both of these therapies are able to produce noticeable results in a short period of time. The aforementioned process of diagnosis leading up to surgery can take months, not including the surgery recovery time, which can take even longer – the overall process can take many months and in some cases over a year. Stem cell and PRP therapies may be able to reduce pain and increase funcationality in a matter of weeks.
Regenerative therapies work best when interacting with soft tissues and can be an excellent option for patients with hip impingement. There is often damage to tendons or joint cartilage in cases of hip impingement, meaning that regenerative therapies can help these parts of the body to heal. When the issue begins in the bone, however, surgery may become necessary. Regenerative therapies do not always offer an option to surpass surgery. If surgery is deemed necessary, regenerative therapies can be included by:
- Injections: some doctors will recommend a patient have stem cell or PRP injections after surgery to help speed up the recovery process. After an invasive surgery such as osteoplasty, the increase in growth factors in the affected area may help reduce pain more rapidly compared to when these therapies are not used.
- PRP or Stem Cell-Infused Surgical String: some surgeons will elect to use a form of surgical string that has platelets or stem cells covering it if the surgery is going to involve sewing to begin with. This allows stem cells or platelets to interact even more intimately with the surgery site and increase the likelihood of a speedier recovery.
Regenerative therapies can be significantly less expensive than surgery and offer hope for a shorter process and faster recovery time. If surgery is deemed necessary, regenerative therapies still offer an option to increase a positive response to surgery.
Hip impingement is fairly common and typically not difficult to treat. The complex anatomy of the bones and cartilage in the ball-and-socket joint can lead to several issues as they are used throughout life. Individuals can be born with an abnormality occurring in the bone which can lead to symptoms of impingement.
People who are active are more susceptible to hip impingement symptoms, but it can happen to anyone at any age with any activity level. Diagnosis is simple as the causes and symptoms of hip impingement are fairly well known.
Depending on the information that doctors accumulate, they will come up with a unique treatment plan. Treatment can have varying degrees of intensity from simple rest to invasive surgery, all depending on the causes and symptoms of impingement.
Regenerative medicine can offer an alternative treatment to these symptoms that allows a patient who has been living with pain and discomfort to navigate their world more comfortably.