What is Hip Pain?

Hip pain explained by Denver, Golden, Aurora, Boulder, Broomfield, Jefferson, and Littleton Colorado’s top pain doctors

Pain occurring in the hip region is quite common and affects millions of adults worldwide. Hip pain can be felt while walking or performing other typical daily activities that involve movement of the pelvic bone or lower extremities. Some instances of hip pain can be so severe that the individual is unable to perform their normal activities. In general, hip pain can be the result of damage or irritation to the muscle, tendons, ligaments, cartilage, or bones.

Typically, instances of hip pain can be traced back to joint damage that is most likely caused by age-related factors. In fact, by the age of 85, it is believed that one in every four adults will suffer from hip degeneration or a hip injury. There are a number of factors that are believed to play a role in the development of hip pain. These may include bone abnormalities or tissue loss, deterioration in the joint’s movement, and a general weakening of the muscles and other tissues surrounding the joint. The risk for these factors is expected to increase with advancing age and may result in difficulties with chronic pain. Patients with chronic pain and discomfort are also at risk for limitations in their joint flexibility and movement, which may lead to trouble performing day-to-day activities. In many cases, the damaged or deteriorating joint will require surgery to replace it with a synthetic prosthesis. Full joint replacement may be avoided with attempts to repair the damaged joint. Using synthetic material to augment bone tissue, the joint can be returned to its original shape and function prior to tissue damage and loss. In some cases, post-operative hip pain can also be a risk factor.

While many instances of hip pain occur among individuals who are of advancing age, the condition of hip pain can occur among individuals of any age, including children. Typically, these cases are the result of genetic structural abnormalities, disorders or other disease states, and occupational injuries.

There are a number of conditions that occur during childhood that have been shown to cause difficulty with either chronic, persistent, and long-lasting pain or acute, sudden, and temporary hip pain. Athletes can account for a very large proportion of the cases of hip pain that occur among populations of adolescents and young adults. While athletes are generally regarded as healthy and active individuals, they are at an increased risk for hip damage associated with the overuse of the hip joint. Athletes, who are involved in highly competitive sports as well as runners, are believed to be most at risk. These individuals may experience symptoms related the overuse of the joint, including strain and tears in the muscle tissue, ligaments, and tendons that surround the joint. In more severe instances, the joint may become dislocated or the bone tissue within the joint can fracture. Individuals experiencing dislocated or fractured joints may require intensive rehabilitation or even surgery to repair damage within the joint.

Accidents that lead to minor fractures of the hip can be relatively common among populations of children. These accidents can occur during typical play or other childhood activities. In many cases, these fractures require surgery and can be somewhat traumatic for a child. Other chronic or genetic conditions may lead to hip pain among populations of children, such as cerebral palsy or Down’s syndrome. In fact, hip abnormalities can often be found among infants, though the pain associated with this condition is not typically experienced throughout their life owing to the availability of proper corrective treatments. Tearing in the labrum, which is the structure that surrounds the hip joint providing it with support, can also lead to hip pain among children and young adults. This condition may lead to long-term difficulties with pain, particularly because labral tears tend to be misdiagnosed.

There are a number of treatments available for hip pain. However, in some causes a total hip replacement may be necessary.

Causes and Pathophysiology of Hip Pain

Hip JointThe hip joint is one of the most important structures of human anatomy. This joint plays a critical role in walking and standing upright, weight bearing on the spine and trunk, as well as the ability to perform complex motor movements, such as jumping, twisting, or bending. The hip joint itself is known as a ball-and-socket joint, given its underlying structure. More specifically, it is comprised of the femoral head, which is the ball-shaped end of the femur (i.e. thigh bone), and the acetabulum of the pelvic bone, which forms the socket area for the femoral head. The ends of these bones forming the joint are protected from damage from bone rubbing again bone by a protective layer of cartilage. This particular region of cartilage is known as the hyaline or articular cartilage. Further, the joint is also surrounded by synovial fluid, which is a viscous material that surrounds the joint, offering a protective buffer against blunt force and aiding in the movement of the joint.

The femur is attached to the pelvis both above and below the joint by ligaments. The hip joint plays a crucial role in many types of daily movements and, thus, exhibits a wide range of motion and is somewhat resilient to trauma. Limitations in movement within the hip joint, however, can be related to the pelvic angle. These are characterized by the pelvis’ structure, as well as the labrum, which surrounds and encases the hip joint. Pain in the hip joint is generally the result of damage or injury to the cartilage, bones, labrum, or other tissues that compromise the hip joint area.

Hip Pain In The Elderly

The main shaft of the femur is connected to the femoral head by a thin bone known as the femoral neck. This small bone can be quite vulnerable to damage. Fractures of the femoral neck are one of the most common fractures occurring among populations of older adults. Individuals with osteoporosis (a common condition occurring in older adults) are most at risk for fractures, given that their bones have progressively become less dense and more brittle. The risk for fractures as the result of osteoporosis with advancing age is compounded by the increased risk for falls among older individuals. Falls are a common source for difficulties with regard to chronic pain and decreases in the ability to function among the elderly. Also commonly occurring during old age is the deterioration of the femoral head in the area where it connects with the acetabulum. Typically, this condition can be traced to osteoporosis and leads to pain in the area of the joint, as well as loss of motion.

Osteoarthritis is another common cause of hip pain occurring among populations of older adults. Osteoarthritis is an autoimmune disease that tends to attack the various tissues that comprise the joint itself, in particular, the synovial fluid that can be found surrounding the bones of the joint. This disease leads to inflammation of the tissues within the joint, which is believed to be the primary cause of pain and discomfort associated with the condition. While this condition does not typically lead to bone damage, it is one of the most common causes of hip replacement to date.

Hip Pain In Children

It is common for children to fracture or otherwise cause damage to their hip joint through accidental injury. For instance, commonly documented among children and adolescents is a fracture that occurs in the femoral head. This fracture is known as the slipped capital femoral epiphysis (SCFE) and leads to the gradual necrosis of the femoral head that occurs as the result of a lack of blood supply. This condition leads to chronic pain in the hip area and the lower extremities, but can also be associated with other more serious conditions, such as avascular necrosis or early onset arthritis. Most instances of SCFE are recommended for total hip replacement surgery. SCFE is typical associated a high degree of physical activity, accidental injury, and higher body mass.

Other conditions associated with hip pain among populations of children include obesity, Down’s syndrome, and cerebral palsy. Children with Down’s syndrome are at an increased risk for a total femoral head collapse, which is also known as Legg-Calvé-Perthes syndrome. Similarly, synovitis can lead to acute symptoms of hip pain among children and is not generally associated with loss of movement or function later in life.

Hip Pain In Adolescents And Young Adults

SCFE has also been associated with femoroacetabular impingement (FAI), which is characterized by an atypical increase in the amount of friction that occurs between the ball and socket of the hip joint. This friction can lead to a high degree of hip pain, as well as a decrease in functionality. Individuals who are particularly at risk for FAI are those involved in heavy athletic activity, runners, and those involved in high-speed and high-impact sports (i.e., hockey). FAI can be commonly misdiagnosed as labral tears or a strain to the adductor muscles of the groin. In general, patients with FAI are treated with reconstructive surgery, which occasionally requires a graft from the patient’s ligaments or other tissues.

Other factors known to contribute to ongoing symptoms of musculoskeletal problems in the lower back, hip, and pelvis are abnormal gait and wearing shoes that affect the distribution of weight on the spine. For instance, high-heel shoes have been shown to lead to difficulties with hip pain.

Other Conditions Related To Hip Pain

There are a number of conditions associated with symptoms of hip pain. In particular, damage to the sacroiliac joint can lead to pain that appears to originate from the hip or pelvic region. Other sources of hip pain include surgical operations on the spine and lower back. These procedures are likely to cause pain in the hip region.

The central nervous system is an unusual source of hip pain. More specifically, abnormal bone growths on the femoral head, or heterotopic ossification, can lead to abnormalities within the joint and inflammation. This then can exacerbate the symptoms of hip pain. Though rare, hip pain can arise from other sources, such as cancer. For instance, cancers that lead to tumors developing on the uterus are a source of hip pain. Cancer may spread through the hip and upper thigh, thereby causing pain. Further, treatment for cancer itself can be associated with significant degrees of pain.

Hip pain can also arise as the result of hip replacement surgery or other surgical procedures. Hip replacement therapy is very common. This procedure involves removing the femoral head or the acetabulum and replacing them with a prosthetic device. More recently these have been constructed from acrylic and are titanium-based. Interestingly, specific types of implants are more associated with post-operative pain than others. Hip pain can also be indicative of an implant failure. The prosthetic device may slip or loosen, causing the device to migrate a bit away from the original location, which can be caused by a faulty device or an infection. In other cases, the femoral head may not fuse properly with the rest of the bone. Prosthetics are generally attached to the shaft of the femur using acrylic cement or screws. This technique also can lead to detachment.

Diagnosis Of Hip Pain

Pelvis DiagramDiagnosis of hip pain can be done through a number of methods. The physician generally will rely upon the patient’s account of recent activity and description of symptoms. Further, the physician is likely to take into account the patient’s medical history and will generally inquire about any previous injuries to the hip and other general health problems. They will want to know about any family history of arthritis or osteoporosis, as this will help the physician arrive at the most accurate diagnosis.

Along with an oral history, physicians will generally conduct a physical examination, particularly in instances of injuries owing to sports. This exam typically includes an assessment of the individual’s degree of strength, mobility, and flexibility. Other tests can be conducted in order to aid in the physician’s diagnosis, such as MRI scans.

Treatments For Hip Pain

Drugs that block the pain receptors along the spine that transmit pain information to the brain, known as opioids, can help treat hip pain.

Oral Medications

NSAIDSSome pain medications may be administered intravenously. While these medications are very effective in reducing the patient’s pain, they are associated with a potential risk for developing addiction and dependency. Further, individuals who are prescribed these medications are at increased risk for liver failure and respiratory depression.

Alternatively, non-steroid anti-inflammatory (NSAIDs) medications are an ideal alternative to opioid medication. Many NSAIDs are available over the counter, such as naproxen, aspirin, or ibuprofen. These medications reduce the degree of inflammation, thus reducing the individual’s level of pain. These medications are effective for treating hip pain associated with sports activities.

Spinal Nerve Blocks

Hip Joint InjectionAn alternative to opioid medications is the use of spinal nerve blocks. This procedure involves injecting a solution of pain-relieving medication, such as mepivacaine or lidocaine, directly into the space that surrounds the affected nerve. Corticosteroids may also be used in these injections. Typically, this procedure involves thoroughly cleaning and sterilizing the surface of the skin around the area of the injection. Imaging techniques are used to ensure that the needle is guided into the proper location. A similar procedure exists, known as a hip joint injection. This injection involves inserting a solution of either anesthetics or steroids directly into the hip joint.

There are a number of benefits to this procedure. Primarily, spinal nerve blocks are generally regarded as safe and effective for the management of chronic pain. Moreover, they can be conducted on an outpatient basis.

There are some risks associated with this procedure, however. Inserting the needle into the incorrect area may lead to nerve damage or loss of sensation. The needle may also be accidentally inserted into a blood vessel. Temporary neurological disturbances may be present. These can be in the form of headache, loss of sensation, overall discomfort, or paralysis. Should steroids be utilized in the procedure, there is some risk for the development of mood changes, weight gain, and immune system depression. The risks for osteoporosis and arthritis are also increased. In terms of hip joint injections specifically, swelling, skin discoloration, and rupture of tendons can occur, though these are rather rare.

Radiofrequency Ablation

RadioFrequency AblationRadiofrequency ablation is another form of nerve block for the treatment of pain. Typically, prior to the procedure, the skin and tissue directly above the targeted nerve is numbed using a local anesthetic. Then a probe is inserted into the area surrounding the targeted nerve and radiofrequency is applied in the form of heat to create a lesion on the affected nerve. It is believed that radiofrequency ablation is effective in managing pain, as it blocks the nerve’s ability to transmit pain signals to the brain.

Radiofrequency ablation is typically recommended for individuals who are experiencing non-severe and non-debilitating degrees of pain. Imaging and other techniques may be utilized to accurately locate the specific area of the nerve to be targeted. There are some risks associated with radiofrequency ablation. These include possible infection, typically in the area where the probe was inserted, minor bleeding, and other feelings of discomfort. Should the probe be placed in an inaccurate position, the patient may be at risk for more serious nerve damage (similar to nerve blocks). Radiofrequency ablation, if successful, is accompanied by many months of pain relief.

Spinal Cord Stimulation (SCS)

Spinal Cord Stimulator - XRAYChronic pain may also be treated by implanting a device into the lumbar region of the spinal cord that is intended to cause interference in the signaling of pain to the brain. This technique is known as spinal cord stimulation (SCS). SCS is a specially designed device that delivers safe and effective relief from pain in the back or hips. The intervention itself involves the use of very small wires, made of a soft and flexible material, which prevents any tissue damage.

The physician will place a test device within the individual that can be used to examine the patient’s response to the treatment. This test device may be implanted for several days until it is determined whether the patient will benefit from the intervention. Should the patient report a positive outcome from this trial implantation, the patient may have a more permanent device implanted. The device is typically attached to a hand-held controller using leads. This allows the patient to have control over when to deliver the stimuli. There are some risks involved in SCS. Most commonly reported are minor bleeding or infection at the insertion site. Further, patients may report a worsening of pain, though this side effect is somewhat rare. Patients undergoing SCS are also at risk for scarring and accidental nerve damage. SCS is quite effective in providing patients with relief from pain and discomfort and the technique is becoming increasingly popular as a form of pain management.

Physical Therapy And Rehabilitation

Hip replacement therapy can lead to significant loss of movement and function of the hip joint. Thus, individuals tend to feel as though they are in a vicious cycle of difficulty with regard to chronic pain and are at risk for additional declines in their ability to perform daily functions. Patients may experience increasing symptoms of difficulty moving, as the tissue in their muscles and ligaments do not readily rehabilitate. Some evidence has suggested, however, that participation in physical therapy can lead to the gradual return of joint function and, over time, the reduction of pain.

Typically, physical therapy includes stretching, joint movements, low-impact exercises, and resistance training. Newer approaches to physical rehabilitation are available that include constrained movement therapy and kinesitherapy. The basis of these techniques was developed utilizing information on the processes underlying the central nervous system’s response to movement. Individuals who are in the process of recovering from corrective surgery are ideal candidates for physical therapy to aid in their ability to return to their pre-operative state.

Acupuncture

AcupunctureThere has been some evidence supporting the benefits of acupuncture in treating hip pain, particularly among those who have recently undergone arthroplasty. This technique utilizes traditional Chinese practices for relieving pain. Using sterilized stainless steel needles, trained acupuncture specialists utilize needle placement to stimulate spinal nerves. Generally, the insertion of these needles is not painful, as they are quite fine. Depending on the patient’s individual account of pain and discomfort, several needles are placed in specific locations to stimulate appropriate nerves. This nerve stimulation then acts to block the nerve’s transmission of pain information to the brain. Some acupuncture specialists will carefully move around the needles or even use electrical stimulation as a way to enhance the effects of the acupuncture procedure. Typically, needles are placed for between 15 to 30 minutes per session. Patients may report numbness or even a tingling sensation following needling placement. Many practitioners recommend a series of treatments for managing symptoms of chronic pain.

There are a number of benefits to treating hip pain using acupuncture techniques. In particular, acupuncture does not involve medication. Moreover, the procedure itself is quick and relatively convenient. Indeed, patients are able to return directly to their normal activities immediately following the procedure. Despite these benefits, there are some risks and complications with regard to acupuncture. Some patients report minor bleeding or bruising at the site of needle insertion. As such, acupuncture is not recommended for individuals with hemophilia or who are taking medications that have blood-thinning attributes, such as regular aspirin. Individuals who are considering acupuncture are strongly encouraged to ensure that the acupuncture specialist is well-trained and reputable, as there is some risk for the transmission of various infectious diseases from the use of unsterilized equipment or the reuse of needles.

Transcutaneous Electrical Nerve Stimulation (TENS)

Another technique that involves stimulating an analgesic response from spinal nerves is through the use of transcutaneous electrical nerve stimulation (TENS). This procedure involves small pads or a cap that is applied to the affected area and delivers electoral impulses that block signals of pain. These electrical impulses are in the form of waves that travel through the surface of the skin to the targeted nerve. The TENS procedure is often recommended for patients who are elderly for controlling the pain and discomfort associated with osteoporosis or osteoarthritis.

TENS has received some support in the literature as an effective treatment for managing pain. Utilizing a sample of 68 post-operative hip replacement patients, one controlled trial found that patients using TENS for managing their post-operative pain were less reliant on fentanyl than those who were in the control group. These findings suggested that TENS may be a potentially ideal treatment for arthroplasty-related pain. TENS is associated with relatively low risks and very few adverse side effects, with the most common side effect reported being stinging or mild burning sensations on the surface of the skin where the pad is applied. Other common symptoms include skin redness and transient muscle pain.

Preventing Hip Pain

In order to avoid the risk of possible injury or damage to the hip joint, which may lead to chronic hip pain, it is generally recommended that individuals engage in prevention techniques. In particular, it is recommended that athletes engage in preventative techniques as they are at an increased risk for developing hip damage as result of inappropriate running or movement styles and over-training. In fact, it is recommended that athletes undergo a running or gait analysis. Findings from these can help with assessing the amount of wear and tear has occurred on the hip as a result of that individual’s gait.

Another technique to prevent future injury is engaging in the proper warm-up routine, taking time to cool down properly following physical activity, and stretching. These exercises act to prevent the muscles from tearing, thereby adding strength to the spine and hip. It may also be necessary for the individual to reduce the degree of training that they engage in.

Currently, it is recommended that aging individuals engage in moderate resistance and flexibility training. This is believed to act as a preventative measure against developing difficulties with hip pain. Resent research has revealed that regular physical activity is essential for the maintenance of bone tissue and for reducing sarcopenia. This age-related reduction in muscle mass has been found to be associated with osteoporosis, osteoporosis-related fractures, and osteoporosis pain. Further, it is well-known that muscle strength can help protect hip integrity.

Other Methods Of Hip Pain Management

Advancing technology has allowed for the development of new and innovative treatments for hip pain and discomfort. These treatments are relatively new and therefore are still undergoing scientific investigation and clinical evaluation. First among these are possible alternatives to the total hip replacement therapy or the total hip arthroplasty. This procedure involves minimal-incision (MI) arthroplasty that is targeted at reducing the patient’s post-operative pain. This method differs from the traditional procedure as it reduces the number of surgical wounds, as well as the orientation of these incisions. Early findings have shown that MI is associated with reductions in the amount of blood loss and recovery time in the hospital. Interestingly, though, the MI procedure has not been shown to be associated with any significant reductions in the amount of post-operative pain that the patient reports. As an alternate procedure to the total hip replacement is the femoral head reconstruction. This procedure involves repairing the surface of the femoral bone with surgical cement. Similarly, this procedure is also found to not be associated with any significant reduction in post-operative pain.

One primary concern with individuals reporting difficulty owing to hip pain is the loss of synovial fluid that is located in the area between the acetabulum and the femoral head. Typically found in arthritis and FAI, a reduction in the volume of the synovial fluid can lead to an increase in friction between the bones of the joint and result in significant degrees of pain. One method that has been explored for replacing this critical fluid is to use bio-medical products, such as hyaluronate. This procedure is known as the viscosupplementation. Unlike the others, it has revealed in early studies to be effective in providing pain relief. This technique is currently being utilized among patients suffering from osteoarthritis. While this procedure has shown promise for treating pain associated with knee-joint arthritis, no studies have been conducted on the benefits of viscosupplementation among individuals with hip pain.

Advances in technology have also led to advances in the procedure for arthroscopy. Currently, this procedure is conducted using an endoscope and is employed to treat FAI and labral tears. This reduces the need for large incisions and, thus, post-operative injury. During the hip arthroscopy procedure, the patient lies down on the operating table with the affected hip upward toward the ceiling. Patients may also lie on their backs. The procedure can be conducted using general anesthesia, spinal nerve block, or femoral nerve block. During the procedure, the hip joint being operated on needs to be dislocated. This means that the ball needs to be removed from the socket. The operating physician will likely use imaging techniques, such as fluoroscopy, as a guide during the procedure. In cases of FAI, surgical micro-burr tools, which are somewhat similar to the dentist drill, remove the abnormal bone growth. Labral tears are generally sealed, cut away, or repaired through the use of autografts. This procedure has been shown to be effective in correcting abnormalities of the hip during infancy, such as dysplasia.

The technique of arthroscopy has been increasingly supported as being related to improved outcomes and recovery time for many painful conditions. This procedure can help reduce the severity of pain and amount of time spent in surgery and recovery. In fact, patients that are treated with arthroscopy are generally expected to recover faster. As with all medical procedures there are some risks associated with arthroscopy. In general, the risks associated are owing to the anesthesia used during the procedure, such as chest numbness and discomfort, nausea, and urinary retention. Though very rare, infection at the site of the injection may occur. Other risks involve mechanical damage to the surrounding tissue, which may lead to chronic pain.

Primarily in control of elongating nerve cells so that they are able to reach their targets, is the nerve growth factor (NGF). This particular factor is of interest currently among individuals researching pain treatments. It is now known that this factor plays a critical role in controlling the transmission of pain signals at the cellular level. Several trials examining NGF and its role in blocking regimens have provided support for their role in providing pain relief. Nonetheless, more research is necessary to support NGFs role in pain management.

Another area of interest among those in research pain management is glucosamine. Glucosamine is an amino-acid derivative found in cartilage that has been shown to benefit individuals with arthritis. Further, glucosamine has been marketed as a dietary supplement that is suspected of improving joint pain as the result of an autoimmune condition. Despite this, findings from existing studies are mixed. Currently, no evidence has been revealed for the role of glucosamine in protecting cartilage or joint friction. Thus, more work is necessary to examine the role of glucosamine for treating hip pain.

Conclusion

Individuals suffering from hip pain can be quite debilitated, as this condition can interfere with normal movement and their ability to function autonomously. Hip pain can arise from a variety of sources. These may include joint damage, inflammation of the spinal nerves that transmit signals of pain to the brain, or injury. While hip pain most commonly occurs among the elderly population, children and young adults are also at risk for developing hip pain.

There are a number of treatment options available to manage hip pain. Many cases of hip pain can been effectively treated using over-the-counter medications. However, for hip pain that does not respond to this first line treatment, patients may try other oral pain relievers, such as morphine. Anesthetic injections may also be recommended for patients whose pain is unresponsive to over-the-counter medication.

In some cases of hip pain, a more long-term pain relieving treatment plan is warranted. In these instances, radiofrequency ablation or a partial lesioning of the spinal nerve may be ideal alternatives. Devices, such as the spinal cord stimulation device or the TENS unit, can also offer a more long-term alternative for managing pain associated with the hips and lower extremities. Acupuncture has also received some support as a complementary intervention for relieving hip pain. Physical therapy is strongly recommended for individuals who have suffered from hip pain as the result of an injury or have just under gone hip replacement surgery.

In addition, prevention of problems that may lead to hip pain is essential. Regular physical activity and exercise, along with stretching, has been shown to have preventative effects on the likelihood of developing hip pain.

At Pain Doctor our goal is to relieve your hip pain and improve function to increase your quality of life.
Give us a call today at 480-563-6400.

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