Juvenile rheumatoid arthritis presents gradually with early morning stiffness, fatigue, and weight loss.

Transient synovitis causes pain in the hip, thigh, groin or knee on the affected side. There may be a limp (or abnormal crawling in infants) with or without pain. In small infants, the presenting complaint can be unexplained crying (for example, when changing a diaper). The condition is nearly always limited to one side. The pain and limp can range from mild to severe.

Some children may have a slightly raised temperature; high fever and general malaise point to other, more serious conditions. On clinical examination, the child typically holds the hip slightly bent, turned outwards and away from the middle line (flexion, external rotation and abduction). Active and passive movements may be limited because of pain, especially abduction and internal rotation. The hip can be tender to palpation. The log roll test involves gently rotating the entire lower limb inwards and outwards with the patient on his back, to check when muscle guarding occurs. The unaffected hip and the knees, ankles, feet and spine are found to be normal.

Transient synovitis is a reactive arthritis of the hip of unknown cause. People are usually able to walk and may have a low grade fever. They usually look clinically nontoxic or otherwise healthy. It may only be diagnosed once all other potential serious causes are excluded. With symptomatic care it usually resolves over one week.

Facet joint arthrosis is an intervertebral disc disorder. The facet joints or zygapophyseal joints are synovial cartilage covered joints that limit the movement of the spine and preserve segmental stability. In the event of hypertrophy of the vertebrae painful arthrosis can occur. The "lumbar facet arthrosis syndrome" was described in a 1987 article by S. M. Eisenstein and C. R. Parry of Witwatersrand University.

The main symptom is pain, causing loss of ability and often stiffness. "Pain" is generally described as a sharp ache or a burning sensation in the associated muscles and tendons, and is typically made worse by prolonged activity and relieved by rest. Stiffness is most common in the morning, and typically lasts less than thirty minutes after beginning daily activities, but may return after periods of inactivity. Osteoarthritis can cause a crackling noise (called "crepitus") when the affected joint is moved or touched and people may experience muscle spasms and contractions in the tendons. Occasionally, the joints may also be filled with fluid. Some people report increased pain associated with cold temperature, high humidity, or a drop in barometric pressure, but studies have had mixed results.

Osteoarthritis commonly affects the hands, feet, spine, and the large weight-bearing joints, such as the hips and knees, although in theory, any joint in the body can be affected. As osteoarthritis progresses, movement patterns (such as gait), are typically affected. Osteoarthritis is the most common cause of a joint effusion of the knee.

In smaller joints, such as at the fingers, hard bony enlargements, called Heberden's nodes (on the distal interphalangeal joints) or Bouchard's nodes (on the proximal interphalangeal joints), may form, and though they are not necessarily painful, they do limit the movement of the fingers significantly. Osteoarthritis of the toes may be a factor causing formation of bunions, rendering them red or swollen.

Computerized tomography is the ideal for typifying facet joint arthrosis; evidence suggests that magnetic resonance imaging is not reliable in this regard.

Enthesopathies may take the form of spondyloarthropathies (joint diseases of the spine) such as ankylosing spondylitis, plantar fasciitis, and Achilles tendinitis. Enthesopathy can occur at the elbow, wrist, carpus, hip, knee, ankle, tarsus, or heel bone, among other regions. Further examples include:

- Adhesive capsulitis of shoulder

- Rotator cuff syndrome of shoulder and allied disorders

- Periarthritis of shoulder

- Scapulohumeral fibrositis

- Synovitis of hand or wrist

- Periarthritis of wrist

- Gluteal tendinitis

- Iliac crest spur

- Psoas tendinitis

- Trochanteric tendinitis

Transient synovitis of the hip (also called toxic synovitis; see below for more synonyms) is a self-limiting condition in which there is an inflammation of the inner lining (the synovium) of the capsule of the hip joint. The term irritable hip refers to the syndrome of acute hip pain, joint stiffness, limp or non-weightbearing, indicative of an underlying condition such as transient synovitis or orthopedic infections (like septic arthritis or osteomyelitis). In everyday clinical practice however, irritable hip is commonly used as a synonym for transient synovitis. It should not be confused with sciatica, a condition describing hip and lower back pain much more common to adults than transient synovitis but with similar signs and symptoms.

Transient synovitis usually affects children between three and ten years old (but it has been reported in a 3-month-old infant and in some adults). It is the most common cause of sudden hip pain and limp in young children. Boys are affected two to four times as often as girls. The exact cause is unknown. A recent viral infection (most commonly an upper respiratory tract infection) or a trauma have been postulated as precipitating events, although these are reported only in 30% and 5% of cases, respectively.

Transient synovitis is a diagnosis of exclusion. The diagnosis can be made in the typical setting of pain or limp in a young child who is not generally unwell and has no recent trauma. There is a limited range of motion of the hip joint. Blood tests may show mild inflammation. An ultrasound scan of the hip joint can show a fluid collection (effusion). Treatment is with nonsteroidal anti-inflammatory drugs and limited weight-bearing. The condition usually clears by itself within seven to ten days, but a small group of patients will continue to have symptoms for several weeks. The recurrence rate is 4–17%, most of which is in the first six months.

In the normal anatomy of the hip joint, the root (the thigh bone) is connected to the pelvis at the hip joint. The almost spherical end of the femur head (the caput, or caput ossis femoris) fits into the acetabulum (a concave socket located in the pelvis). The bony surfaces of the femur head and of the acetabulum are covered by cartilage. While bones provide the strength necessary to support body weight, cartilage ensures a smooth fit and a wide range of motion. Normal hip function can be affected by congenital conditions such as dysplasia, discussed in this article, trauma, and by acquired diseases such as osteoarthritis and rheumatoid arthritis.

In medicine, an enthesopathy refers to a disorder involving the attachment of a tendon or ligament to a bone. This site of attachment is known as the entheses.

If the condition is known to be inflammatory, it can more precisely be called an enthesitis.

The classic clinical presentation of a hip fracture is an elderly patient who sustained a low-energy fall and now has groin pain and is unable to bear weight. Pain may be referred to the supracondylar knee. On examination, the affected extremity is often shortened and unnaturally, externally rotated compared to the unaffected leg.

Osteoarthritis (OA) is a type of joint disease that results from breakdown of joint cartilage and underlying bone. The most common symptoms are joint pain and stiffness. Initially, symptoms may occur only following exercise, but over time may become constant. Other symptoms may include joint swelling, decreased range of motion, and when the back is affected weakness or numbness of the arms and legs. The most commonly involved joints are those near the ends of the fingers, at the base of the thumb, neck, lower back, knee, and hips. Joints on one side of the body are often more affected than those on the other. Usually the symptoms come on over years. It can affect work and normal daily activities. Unlike other types of arthritis, only the joints are typically affected.

Causes include previous joint injury, abnormal joint or limb development, and inherited factors. Risk is greater in those who are overweight, have one leg of a different length, and have jobs that result in high levels of joint stress. Osteoarthritis is believed to be caused by mechanical stress on the joint and low grade inflammatory processes. It develops as cartilage is lost and the underlying bone becomes affected. As pain may make it difficult to exercise, muscle loss may occur. Diagnosis is typically based on signs and symptoms, with medical imaging and other tests occasionally used to either support or rule out other problems. In contrast to rheumatoid arthritis, which is primarily an inflammatory condition, in osteoarthritis, the joints do not typically become hot or red.

Treatment includes exercise, efforts to decrease joint stress, support groups, and pain medications. Efforts to decrease joint stress include resting and the use of a cane. Weight loss may help in those who are overweight. Pain medications may include paracetamol (acetaminophen) as well as NSAIDs such as naproxen or ibuprofen. Long-term opioid use is generally discouraged due to lack of information on benefits as well as risks of addiction and other side effects. If pain interferes with normal life despite other treatments, joint replacement surgery may help. An artificial joint typically lasts 10 to 15 years.

Osteoarthritis is the most common form of arthritis affecting about 237 million (3.3%) of the population. Among those over 60 years old, about 10% of males and 18% of females are affected. It is the cause of about 2% of years lived with disability. In Australia, about 1.9 million people are affected, and in the United States, 30 to 52.5 million people are affected. It becomes more common in both sexes as people become older.

The onset of the condition is usually gradual, although some cases may appear suddenly following trauma.

- Knee pain - the most common symptom is diffuse peripatellar pain (vague pain around the kneecap) and localized retropatellar pain (pain focused behind the kneecap). Affected individuals typically have difficulty describing the location of the pain, and may place their hands over the anterior patella or describe a circle around the patella (the "circle sign"). Pain is usually initiated when load is put on the knee extensor mechanism, e.g. ascending or descending stairs or slopes, squatting, kneeling, cycling, running or prolonged sitting with flexed (bent) knees. The latter feature is sometimes termed the "movie sign" or "theatre sign" because individuals might experience pain while sitting to watch a film or similar activity. The pain is typically aching with occasional sharp pains.

- Crepitus (joint noises) may be present

- Giving-way of the knee may be reported

Petplan Australia reported that signs of arthritis in dogs and cats include stiffness, difficulty moving, lethargy, irritability, and cat or dog may lick, chew or bite at sore joints.

Dogs might exhibit signs of stiffness or soreness after rising from rest, reluctance to exercise, bunny-hopping or other abnormal gait (legs move more together when running rather than swinging alternately), lameness, pain, reluctance to stand on rear legs, jump up, or climb stairs, subluxation or dislocation of the hip joint, or wasting away of the muscle mass in the hip area. Radiographs (X-rays) often confirm the presence of hip dysplasia, but radiographic features may not be present until two years of age in some dogs. Moreover, many affected dogs do not show clinical signs, but some dogs manifest the problem before seven months of age, while others do not show it until well into adulthood.

In part this is because the underlying hip problem may be mild or severe, may be worsening or stable, and the body may be more or less able to keep the joint in repair well enough to cope. Also, different animals have different pain tolerances and different weights, and use their bodies differently, so a light dog who only walks, will have a different joint use than a more heavy or very active dog. Some dogs will have a problem early on, others may never have a real problem at all.

Usually, a SCFE causes groin pain, but it may cause pain in only the thigh or knee, because the pain may be referred along the distribution of the obturator nerve. The pain may occur on both sides of the body (bilaterally), as up to 40 percent of cases involve slippage on both sides. After a first SCFE, when a second SCFE occurs on the other side, it typically happens within one year after the first SCFE. About 20 percent of all cases include a SCFE on both sides at the time of presentation.

Signs of a SCFE include a waddling gait, decreased range of motion. Often the range of motion in the hip is restricted in internal rotation, abduction, and flexion. A person with a SCFE may prefer to hold their hip in flexion and external rotation.

An extracapsular fracture is a bone fracture near a joint but still located outside the joint capsule.

Examples of extracapsular fractures are intertrochanteric and subtrochanteric hip fractures.

Chondromalacia patellae is a term sometimes treated synonymously with PFPS. However, there is general consensus that PFPS applies only to individuals without cartilage damage, thereby distinguishing it from chondromalacia patellae, a condition characterized by softening of the patellar articular cartilage. Despite this academic distinction, the diagnosis of PFPS is typically made clinically, based only on the history and physical examination rather than on the results of any medical imaging. Therefore, it is unknown whether most persons with a diagnosis of PFPS have cartilage damage or not, making the difference between PFPS and chondromalacia theoretical rather than practical. It is thought that only some individuals with anterior knee pain will have true chondromalacia patellae.

Failure to treat a SCFE may lead to: death of bone tissue in the femoral head (avascular necrosis), degenerative hip disease (hip osteoarthritis), gait abnormalities and chronic pain. SCFE is associated with a greater risk of arthritis of the hip joint later in life. 17-47 percent of acute cases of SCFE lead to the death of bone tissue (osteonecrosis) effects.

Common symptoms include hip, knee (hip pathology can refer pain to a normal knee), or groin pain, exacerbated by hip or leg movement, especially internal hip rotation (with the knee flexed 90°, twisting the lower leg away from the center of the body). The range of motion is reduced, particularly in abduction and internal rotation, and the patient presents with a limp. Pain is usually mild. Atrophy of thigh muscles may occur from disuse and an inequality of leg length. In some cases, some activity can cause severe irritation or inflammation of the damaged area, including standing, walking, running, kneeling, or stooping repeatedly for an extended period of time. In cases exhibiting severe femoral osteonecrosis, pain is usually a chronic, throbbing sensation exacerbated by activity.

The first signs are complaints of soreness from the child, which are often dismissed as growing pains, and limping or other guarding of the joint, particularly when tired. The pain is usually in the hip, but can also be felt in the knee (referred pain). In some cases, pain is felt in the unaffected hip and leg, due to the children favoring their injured side and placing the majority of their weight on their "good" leg. It is predominantly a disease of boys (4:1 ratio). Perthes is generally diagnosed between 5 and 12 years of age, although it has been diagnosed as early as 18 months. Typically, the disease is only seen in one hip, but bilateral Perthes is seen in about 10% of children diagnosed.

In general, pigmented villonodular synovitis often manifests initially as sudden onset, unexplained joint swelling and pain; the joint swelling is disproportionate to the amount of pain the patient feels at first. Decreased motion and increased pain occur as the disorder progresses as well as locking of the joint. The localized form often manifests initially as a painless, slow-growing mass and progresses to the other common symptoms of PVNS. The swelling often feels warm to the touch. Diffuse PVNS symptoms are often confused with those of Rheumatoid arthritis. While pigmented villonodular synovitis can occur in both pediatric and geriatric patients, it is more common with ages 20–50.

Dislocation of the hip is a common injury to the hip joint. Dislocation occurs when the ball–shaped head of the femur comes out of the cup–shaped acetabulum set in the pelvis.

Dislocations may be developmental or due to acute trauma. The emphasis of this article is on acute dislocation. For developmental dislocation, see hip dysplasia.

Acute traumatic hip dislocations are severe injuries. These dislocations typically occur in 16- to 40-year-olds involved in high energy trauma like motor vehicle accidents.

These conditions nearly all present with an insidious onset of pain referred to the location of the bony damage. Some, notably Kienbock's disease of the wrist, may involve considerable swelling, and Legg-Calvé-Perthes disease of the hip causes the victim to limp. The spinal form, Scheuermann's disease, may cause bending, or kyphosis of the upper spine, giving a "hunch-back" appearance.

A hip fracture is a break that occurs in the upper part of the femur (thigh bone). Symptoms may include pain around the hip particularly with movement and shortening of the leg. Usually the person cannot walk.

They most often occur as a result of a fall. Risk factors include osteoporosis, taking many medications, alcohol use, and metastatic cancer. Diagnosis is generally by X-rays. Magnetic resonance imaging, a CT scan, or a bone scan may occasionally be required to make the diagnosis.

Pain management may occur with opioids or a nerve block. If a person's health is sufficient, surgery is generally recommended within two days. Options for surgery may include a total hip replacement or screws. Efforts to prevent deep vein thrombosis following surgery are recommended.

About 15% of women break their hip at some point in their life. Women are more often affected than men. Hip fractures become more common with age. The risk of death in the year following a fracture is about 20% in older people.

PVNS is locally aggressive and can spread to surrounding tissues, causing bone erosion and tissue damage. If not treated early, it can spread to areas outside the joint, and potentially cause permanent loss of range as well as intense pain. The disorder also has, on average, a 45% rate of recurrence.

Trauma from ligamentous, osseous or meniscal injuries can result in an effusion. These are often hemarthrosis or bloody effusions.