Femoral Acetabular Impingement
Encyclopedia
Femoroacetabular Impingement (FAI) or hip impingement syndrome is a condition affecting the hip joint in young and middle-aged adults. Impingement occurs when the ball shaped femoral head rubs abnormally or doesn't have full range of motion in the acetabular
socket. Damage in the hip joint can occur to the articular cartilage
or the labral
cartilage (soft tissue bumper of the socket). Treatment options vary from conservative treatment to arthroscopic and open surgery.
and rim of the acetabulum
(hip socket). In most cases patients presenting with a deformity in the femoral head
or acetabulum, a poorly positioned femoral-acetabular junction or the presence of both conditions are symptomatic of FAI. It is believed that a combination of certain factors may lead to some form of FAI. Predominantly a marginal developmental hip abnormality together with environmental factors such as the partaking in activities involving recurrent motion of the legs within a supraphysiologic range.
There are three types of FAI. The first involves an excess of bone along the upper surface of the femoral head: this is known as a Cam deformity, the name being derived from the Dutch word for cog
. The second is due to an excess of growth of the upper lip of the acetabular cup and is known as the Pincer deformity. The third is a mixture of the preceding two forms. The result of any of these deformities is increased friction between the acetabular cup and femoral head which may result in pain and loss or reduction of hip function.
Many activities involving recurrent hip motion increase the frequency of this abnormal contact in FAI sufferers. These include sports such as soccer, ice-skating and gymnastics
. However, FAI-related pain may occur within a normal range of motion during actions not normally associated with a need for physical demand such as the motions of sitting down and standing up. This condition generally manifests itself in three forms: cam impingement, pincer impingement or mixed cam and pincer impingement. In cam impingement there is an abnormal bony lesion on the femoral head. In pincer impingement there is a bony lesion on the acetabulum which leads to over-coverage of the femoral head. In mixed cam and pincer impingement both conditions exist.
Some medical experts believe this to be a trigger or the beginning of hip osteoarthritis
. Without hip-preserving treatment, there is a high likelihood of developing osteoarthritis with the subsequent requirement of a hip replacement
procedure if still left untreated.
in which the range of motion of the leg in relation to the hip is tested. Positive limited flexibility would lead to further examination with x-ray
, for a two-dimensional view of the hip joints. Subsequent imaging techniques such as a CT
or MRI scan may then be used in order to produce a three-dimensional image showing the angles of the hip sockets, in addition to the condition of hip cartilage
or signs of osteoarthritis
.
. Conservative/nonsurgical treatments should always be considered first. This can include reducing levels of physical activity and having pain medication and physiotherapy sessions. Physical Therapy [physiotherapy] intervention may help to optimize alignment and mobility of the hip joint, therefore, decreasing excessive forces on irritable or weakened tissues. Physical Therapy can also help to identify specific movement patterns that may be injuring the involved hip. These types of interventions may be successful in reducing the pain and swelling in the joint, although in some cases, physical therapy can cause symptoms to worsen. Those who choose this route may require a hip replacement
later in life. However, depending on the condition of the patient (e.g. elderly with advanced osteoarthritis), a hip replacement
may be the best course of treatment. The downside of this is the need for subsequent hip replacement procedures and the limiting effects of the artificial hip.
Due to the condition being diagnosed frequently in adolescents and young adults, various surgical techniques have been developed in order to preserve the hip joint, preventing the need for a total hip replacement and allowing the patient to continue with an active lifestyle. Surgery may be arthroscopic or open. Periacetabular or rotational osteotomies
are two common open surgery techniques that may be performed if investigations have shown there to be an abnormal angle of the hip joint. These primarily aim to alter the angle of the hip socket in such a way that contact between the acetabulum and femoral head are greatly reduced, allowing a greater range of movement. Femoral sculpting may be performed simultaneously, if required for a better overall shape of the hip joint.
Acetabulum
The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...
socket. Damage in the hip joint can occur to the articular cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
or the labral
Acetabular labrum
The acetabular labrum is a ring of cartilage that surrounds the acetabulum ....
cartilage (soft tissue bumper of the socket). Treatment options vary from conservative treatment to arthroscopic and open surgery.
Overview
This affliction is characterised by abnormal contact between the proximal femurFemur
The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
and rim of the acetabulum
Acetabulum
The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...
(hip socket). In most cases patients presenting with a deformity in the femoral head
Femur head
The femur head is the highest part of the thigh bone . It is supported by the neck of the femur.The head is globular and forms rather more than a hemisphere, is directed upward, medialward, and a little forward, the greater part of its convexity being above and in front.Its surface is smooth,...
or acetabulum, a poorly positioned femoral-acetabular junction or the presence of both conditions are symptomatic of FAI. It is believed that a combination of certain factors may lead to some form of FAI. Predominantly a marginal developmental hip abnormality together with environmental factors such as the partaking in activities involving recurrent motion of the legs within a supraphysiologic range.
There are three types of FAI. The first involves an excess of bone along the upper surface of the femoral head: this is known as a Cam deformity, the name being derived from the Dutch word for cog
Cog
Cog may refer to:* A part of a gear system* Cog , a small sailing vessel* A tenon that extends all the way through another piece of wood, in joinery* The evil robots in Toontown Online...
. The second is due to an excess of growth of the upper lip of the acetabular cup and is known as the Pincer deformity. The third is a mixture of the preceding two forms. The result of any of these deformities is increased friction between the acetabular cup and femoral head which may result in pain and loss or reduction of hip function.
Many activities involving recurrent hip motion increase the frequency of this abnormal contact in FAI sufferers. These include sports such as soccer, ice-skating and gymnastics
Gymnastics
Gymnastics is a sport involving performance of exercises requiring physical strength, flexibility, agility, coordination, and balance. Internationally, all of the gymnastic sports are governed by the Fédération Internationale de Gymnastique with each country having its own national governing body...
. However, FAI-related pain may occur within a normal range of motion during actions not normally associated with a need for physical demand such as the motions of sitting down and standing up. This condition generally manifests itself in three forms: cam impingement, pincer impingement or mixed cam and pincer impingement. In cam impingement there is an abnormal bony lesion on the femoral head. In pincer impingement there is a bony lesion on the acetabulum which leads to over-coverage of the femoral head. In mixed cam and pincer impingement both conditions exist.
Some medical experts believe this to be a trigger or the beginning of hip osteoarthritis
Osteoarthritis
Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion...
. Without hip-preserving treatment, there is a high likelihood of developing osteoarthritis with the subsequent requirement of a hip replacement
Hip replacement
Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. Hip replacement surgery can be performed as a total replacement or a hemi replacement. Such joint replacement orthopaedic surgery generally is conducted to relieve arthritis pain or fix severe...
procedure if still left untreated.
Diagnosis
In sufferers, FAI-related pain may be felt in the groin, lower back and generally around the hip. The diagnosis of FAI typically involves a physical examinationPhysical examination
Physical examination or clinical examination is the process by which a doctor investigates the body of a patient for signs of disease. It generally follows the taking of the medical history — an account of the symptoms as experienced by the patient...
in which the range of motion of the leg in relation to the hip is tested. Positive limited flexibility would lead to further examination with x-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
, for a two-dimensional view of the hip joints. Subsequent imaging techniques such as a CT
Computed tomography
X-ray computed tomography or Computer tomography , is a medical imaging method employing tomography created by computer processing...
or MRI scan may then be used in order to produce a three-dimensional image showing the angles of the hip sockets, in addition to the condition of hip cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
or signs of osteoarthritis
Osteoarthritis
Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion...
.
Treatment
The treatments for FAI vary considerably. Sufferers may be shown how to manage their condition and forego surgerySurgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...
. Conservative/nonsurgical treatments should always be considered first. This can include reducing levels of physical activity and having pain medication and physiotherapy sessions. Physical Therapy [physiotherapy] intervention may help to optimize alignment and mobility of the hip joint, therefore, decreasing excessive forces on irritable or weakened tissues. Physical Therapy can also help to identify specific movement patterns that may be injuring the involved hip. These types of interventions may be successful in reducing the pain and swelling in the joint, although in some cases, physical therapy can cause symptoms to worsen. Those who choose this route may require a hip replacement
Hip replacement
Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. Hip replacement surgery can be performed as a total replacement or a hemi replacement. Such joint replacement orthopaedic surgery generally is conducted to relieve arthritis pain or fix severe...
later in life. However, depending on the condition of the patient (e.g. elderly with advanced osteoarthritis), a hip replacement
Hip replacement
Hip replacement is a surgical procedure in which the hip joint is replaced by a prosthetic implant. Hip replacement surgery can be performed as a total replacement or a hemi replacement. Such joint replacement orthopaedic surgery generally is conducted to relieve arthritis pain or fix severe...
may be the best course of treatment. The downside of this is the need for subsequent hip replacement procedures and the limiting effects of the artificial hip.
Due to the condition being diagnosed frequently in adolescents and young adults, various surgical techniques have been developed in order to preserve the hip joint, preventing the need for a total hip replacement and allowing the patient to continue with an active lifestyle. Surgery may be arthroscopic or open. Periacetabular or rotational osteotomies
Osteotomy
An osteotomy is a surgical operation whereby a bone is cut to shorten, lengthen, or change its alignment. It is sometimes performed to correct a hallux valgus, or to straighten a bone that has healed crookedly following a fracture. It is also used to correct a coxa vara, genu valgum, and genu varum...
are two common open surgery techniques that may be performed if investigations have shown there to be an abnormal angle of the hip joint. These primarily aim to alter the angle of the hip socket in such a way that contact between the acetabulum and femoral head are greatly reduced, allowing a greater range of movement. Femoral sculpting may be performed simultaneously, if required for a better overall shape of the hip joint.