X-rays show lucency of the ossification front in juveniles. In older people, the lesion typically appears as an area of osteosclerotic bone with a radiolucent line between the osteochondral defect and the epiphysis. The visibility of the lesion depends on its location and on the amount of knee flexion used. Harding described the lateral X-ray as a method to identify the site of an OCD lesion.

Magnetic resonance imaging (MRI) is useful for staging OCD lesions, evaluating the integrity of the joint surface, and distinguishing normal variants of bone formation from OCD by showing bone and cartilage edema in the area of the irregularity. MRI provides information regarding features of the articular cartilage and bone under the cartilage, including edema, fractures, fluid interfaces, articular surface integrity, and fragment displacement. A low T1 and high T2 signal at the fragment interface is seen in active lesions. This indicates an unstable lesion or recent microfractures. While MRI and arthroscopy have a close correlation, X-ray films tend to be less inductive of similar MRI results.

Computed tomography (CT) scans and Technetium-99m bone scans are also sometimes used to monitor the progress of treatment. Unlike plain radiographs (X-rays), CT scans and MRI scans can show the exact location and extent of the lesion. Technetium bone scans can detect regional blood flow and the amount of osseous uptake. Both of these seem to be closely correlated to the potential for healing in the fragment.

Physical examination often begins with examination of the patient's gait. In OCD of the knee, people may walk with the involved leg externally rotated in an attempt to avoid tibial spine impingement on the lateral aspect of the medial condyle of the femur.

Next, the examining physician may check for weakness of the quadriceps. This examination may reveal fluid in the joint, tenderness, and crepitus. The Wilson test is also useful in locating OCD lesions of the femoral condyle. The test is performed by slowly extending the knee from 90 degrees, maintaining internal rotation. Pain at 30 degrees of flexion and relief with tibial external rotation is indicative of OCD.

Physical examination of a patient with ankle OCD often returns symptoms of joint effusion, crepitus, and diffuse or localized tenderness. Examination often reveals symptoms of generalized joint pain, swelling, and times with limited range of motion. Some with loose body lesions may report catching, locking, or both. The possibility of microtrauma emphasizes a need for evaluation of biomechanical forces at the knee in a physical examination. As a result, the alignment and rotation of all major joints in the affected extremity is common, as are extrinsic and intrinsic abnormalities concerning the affected joint, including laxity.

The classic diagnostic technique is with appropriate X-rays and hip scoring tests. These should be done at an appropriate age, and perhaps repeated at adulthood - if done too young they will not show anything. Since the condition is to a large degree inherited, the hip scores of parents should be professionally checked before buying a pup, and the hip scores of dogs should be checked before relying upon them for breeding. Despite the fact that the condition is inherited, it can occasionally arise even to animals with impeccably hip scored parents.

In diagnosing suspected dysplasia, the x-ray to evaluate the internal state of the joints is usually combined with a study of the animal and how it moves, to confirm whether its quality of life is being affected. Evidence of lameness or abnormal hip or spine use, difficulty or reduced movement when running or navigating steps, are all evidence of a problem. Both aspects have to be taken into account since there can be serious pain with little X-ray evidence.

It is also common to X-ray the spine and legs, as well as the hips, where dysplasia is suspected, since soft tissues can be affected by the extra strain of a dysplastic hip, or there may be other undetected factors such as neurological issues (e.g. nerve damage) involved.

There are several standardized systems for categorising dysplasia, set out by respective reputable bodies (Orthopedic Foundation for Animals/OFA, PennHIP, British Veterinary Association/BVA). Some of these tests require manipulation of the hip joint into standard positions, in order to reveal their condition on an X-ray.

The following conditions can give symptoms very similar to hip dysplasia, and should be ruled out during diagnosis:

- Cauda equina syndrome (i.e. lower back problems)

- Cranial (anterior) cruciate ligament tears

- Other rear limb arthritic conditions

- Osteochondritis dissecans and elbow dysplasia in the forelimbs are difficult to diagnose as the animal may only exhibit an unusual gait, and may be masked by, or misdiagnosed as, hip dysplasia.

A dog may misuse its rear legs, or adapt its gait, to compensate for pain in the "forelimbs", notably osteoarthritis, osteochondritis (OCD) or shoulder or elbow dysplasia, as well as pain in the hocks and stifles or spinal issues. It is important to rule out other joint and bodily issues before concluding that only hip dysplasia is present. Even if some hip dysplasia is present, it is possible for other conditions to co-exist or be masked by it.

As the symptoms become prominent, the child will visit their pediatrician or family doctor to confirm whether or not the child has Panner Disease. When the child visits the doctor, the doctor will seek information about the child’s age, sports participation, activity level, and what the child’s dominant arm is. The affected elbow will be compared to the healthy elbow and any differences between the two will be noted. The location of where the pain is in the elbow, and the child’s range of motion and extension will also be determined to make an accurate diagnosis. To check the child’s range of motion and extension limitation the child will be asked to move the arm of the affected elbow in various directions. The movement of the arm in various directions will allow the doctor to conclude how good the child is able to move the arm and the doctor will be able to determine if there is pain caused by the various directions of movement.

To confirm the diagnosis, an x-ray or MRI scan will be done. The radiograph will enable the doctor to visualize irregularities and see the shape of the capitellum and also visualize the growth plate. In Panner Disease, the capitellum may appear flat and the bone growth plate will look irregular and fragmented. The areas where bone breakdown has occurred can also be visualized on the radiograph. When the patient undergoes a MRI scan any irregularities of the capitellum will able to be visualized, and the bone will be able to be visualized in more detail to determine the extent of swelling, if any. In the MRI results for Panner disease, there will be a decreased signal intensity of the capitellum on a T1 series and increased signal intensity on a T2 series.

Diagnosis is through x-rays, arthroscopy or CT (computed tomography). In cases with significant lameness, surgery is the best option, especially with UAP. However, conservative treatment is often enough for cases of FMCP and OCD of the medial humeral epicondyle. The dogs are exercised regularly and given pain medication, and between the ages of 12 to 18 months the lameness will often improve or disappear. Control of body weight is important in all cases of elbow dysplasia, and prevention of quick growth spurts in puppies may help to prevent the disease.

Surgery for FMCP consists of removal of cartilage and bone fragments and correction of any incongruity of the joint. Reattachment of UAP with a screw is usually attempted before the age of 24 weeks, and after that age the typical treatment is removal of the UAP. Without surgery, UAP rapidly progresses to osteoarthritis, but with FMCP osteoarthritis typically occurs with or without surgery. Osteoarthritis is also a common sequela of OCD of the humerus despite medical or surgical treatment. Elbow replacement surgery has been developed and can be an option for treatment

Being an extremely rare disease, it is unknown as to what exactly causes Panner Disease. It is believed that the disease may be brought on by continuous overuse of the elbow and that puts pressure on the elbow and also strains the elbow in children during the period of rapid bone growth. The overuse of the elbow can be due to the involvement in sports such as baseball, handball, and gymnastics where these sports involve throwing or putting a lot of pressure on the joints. These repeated activities cause microtraumas and results in the affected elbow being swollen, irritated, and in pain. Panner Disease results when the blood supply to the capitellum is disrupted and therefore the cells within the growth plate of the capitellum die and it becomes flat due to the softening and collapsing of the surrounding bone. To prevent future instances of Panner Disease the child is instructed to cease all physical and sports activities that involve the use of the affected elbow until the symptoms are relieved.

The Orthopedic Foundation for Animals in the United States will grade elbow X-rays of dogs intended for breeding.

Osteochondritis is a painful type of osteochondrosis where the cartilage or bone in a joint is inflamed.

It often refers to osteochondritis dissecans (sometimes spelt "dessecans", and abbreviated OCD). The term "dissecans" refers to the "creation of a flap of cartilage that further dissects away from its underlying subchondral attachments (dissecans)".

The other recognized types of osteochondritis are osteochondritis deformans juvenilis (osteochondritis of the capitular head of the epiphysis of the femur) and osteochondritis deformans juvenilis dorsi (osteochondrosis of the spinal vertebrae, also known as Scheuermann's disease).

Osteochondritis, and especially osteochondritis dissecans, can manifest in animals as a primary cause of elbow dysplasia, a chronic condition in some species and breeds.

Typically, individuals with excoriation disorder find that the disorder interferes with daily life. Hindered by shame, embarrassment, and humiliation, they may take measures to hide their disorder by not leaving home, wearing long sleeves and pants even in heat, or covering visible damage to skin with cosmetics and/or bandages. Activities such as typing may be painful for those who pick at their fingers or hands, or walking for those who pick at the soles of their feet.

No pathognomonic clinical signs for TSC complex are seen. Many signs are present in individuals who are healthy (although rarely), or who have another disease. In order to meet diagnostic criteria for TSC complex, an individual must either have: 1) Two or more major criteria; or 2) One major criterion along with two or more minor criteria.

In infants, the first clue is often the presence of seizures, delayed development, or white patches on the skin. A full clinical diagnosis involves:

- Taking a personal and family history

- Examining the skin under a Wood's lamp (hypomelanotic macules), the fingers and toes (ungual fibroma), the face (angiofibromas), and the mouth (dental pits and gingival fibromas)

- Cranial imaging with nonenhanced CT or, preferably, MRI (cortical tubers and subependymal nodules)

- Renal ultrasound (angiomyolipoma or cysts)

- An echocardiogram in infants (rhabdomyoma)

- Fundoscopy (retinal nodular hamartomas or achromic patch)

The various signs are then marked against the diagnostic criteria to produce a level of diagnostic certainty:

- Definite – either two major features or one major feature plus two minor features

- Probable – one major plus one minor feature

- Suspect – either one major feature or two or more minor features

Due to the wide variety of mutations leading to TSC, no simple genetic tests are available to identify new cases, nor are any biochemical markers known for the gene defects. However, once a person has been clinically diagnosed, the genetic mutation can usually be found. The search is time-consuming and has a 15% failure rate, which is thought to be due to somatic mosaicism. If successful, this information can be used to identify affected family members, including prenatal diagnosis. , preimplantation diagnosis is not widely available.

There are no definitive diagnostic tests for CP/CPPS. This is a poorly understood disorder, even though it accounts for 90–95% of prostatitis diagnoses. It is found in men of any age, with the peak incidence in men aged 35–45 years. CP/CPPS may be inflammatory (Category Ⅲa) or non-inflammatory (Category Ⅲb), based on levels of pus cells in expressed prostatic secretions (EPS), but these subcategories are of limited use clinically. In the inflammatory form, urine, semen, and other fluids from the prostate contain pus cells (dead white blood cells or WBCs), whereas in the non-inflammatory form no pus cells are present. Recent studies have questioned the distinction between categories Ⅲa and Ⅲb, since both categories show evidence of inflammation if pus cells are ignored and other more subtle signs of inflammation, like cytokines, are measured.

In 2006, Chinese researchers found that men with categories Ⅲa and Ⅲb both had significantly and similarly raised levels of anti-inflammatory cytokine TGFβ1 and pro-inflammatory cytokine IFN-γ in their EPS when compared with controls; therefore measurement of these cytokines could be used to diagnose category Ⅲ prostatitis. A 2010 study found that nerve growth factor could also be used as a biomarker of the condition.

For CP/CPPS patients, analysis of urine and expressed prostatic secretions for leukocytes is debatable, especially due to the fact that the differentiation between patients with inflammatory and non-inflammatory subgroups of CP/CPPS is not useful. Serum PSA tests, routine imaging of the prostate, and tests for Chlamydia trachomatis and Ureaplasma provide no benefit for the patient.

Extraprostatic abdominal/pelvic tenderness is present in >50% of patients with chronic pelvic pain syndrome but only 7% of controls.

Healthy men have slightly more bacteria in their semen than men with CPPS. The high prevalence of WBCs and positive bacterial cultures in the asymptomatic control population raises questions about the clinical usefulness of the standard 4-glass test as a diagnostic tool in men with CP/CPPS. The use of the four-glass test by American urologists is now rare, with only 4% using it regularly.

Men with CP/CPPS are more likely than the general population to suffer from Chronic Fatigue Syndrome (CFS), and Irritable Bowel Syndrome (IBS).

Experimental tests that could be useful in the future include tests to measure semen and prostate fluid cytokine levels. Various studies have shown increases in markers for inflammation such as elevated levels of cytokines, myeloperoxidase, and chemokines.

Some conditions have similar symptoms to chronic prostatitis: Bladder neck hypertrophy and urethral stricture may both cause similar symptoms through urinary reflux ("inter alia"), and can be excluded through flexible cytoscopy and urodynamic tests.

At the time of first PANS presentation, note any family history of pharyngitis, impetigo, perianal dermatitis, and GAS infections. If possible, family members should have a throat swab cultured for GAS. Ongoing vigilance against GAS infections in any of the patient’s close contacts is important, as symptom exacerbations have been reported following exposure to a sibling with GAS (even when the PANDAS patient had no evidence of infection). Prompt medical attention to symptoms suggestive of streptococcal infection is important not only to protect the patient, but also siblings, who may be at an increased genetic risk for PANS.

Every disease has different signs and symptoms. Some of them are persistent headache; pain in the face, back, arms, or legs; an inability to concentrate; loss of feeling; memory loss; loss of muscle strength; tremors; seizures; increased reflexes, spasticity, tics; paralysis; and slurred speech. One should seek medical attention if affected by these.

There has been controversy over the creation of a separate category in the DSM-5 for excoriation (skin picking) disorder. Two of the main reasons for objecting to the inclusion of excoriation disorder in the DSM-5 are: (1) that excoriation disorder may just be a symptom of a different underlying disorder, e.g. OCD or BDD, and (2) that excoriation disorder is merely a bad habit and that by allowing this disorder to obtain its own separate category it would force the DSM to include a wide array of bad habits as separate syndromes, e.g., nail biting and nose-picking. Stein has argued that excoriation disorder does qualify as a separate syndrome and should be classified as its own category because: (1) excoriation disorder occurs as the primary disorder and not as a subset of a larger disorder; (2) excoriation disorder has well-defined clinical features; (3) there is gathering data on the clinical features and diagnostic criteria for this condition; (4) there is sufficient data to create this as a separate category for excoriation disorder; (5) the incidence rate for excoriation disorder is high within the population; (6) diagnostic criteria for the disease have already been proposed; (7) the classification of excoriation disorder as a separate condition would lead to better studies and better treatment outcomes; and (8) classification as a separate condition would lead to more awareness of the disorder and encourage more people to obtain treatment.

Because excoriation disorder is different from other conditions and disorders that cause picking of the skin, it is important that any diagnosis of excoriation disorder take into account various other medical conditions as possible causes before diagnosing the patient with excoriation disorder. There are a variety of conditions that cause itching and skin picking including: eczema, psoriasis, diabetes, liver disease, Hodgkin's disease, polycythemia vera, systemic lupus, and Prader-Willi syndrome.

In order to better understand excoriation disorder, researchers have developed a variety of scales to categorize skin-picking behavior. These include the Skin-Picking Impact Scale (SPIS), and The Milwaukee Inventory for the Dimensions of Adult Skin-picking. The SPIS was created to measure how skin picking affects the individual socially, behaviorally, and emotionally.

As of the release of the fifth Diagnostic and Statistical Manual of Mental Disorders in May 2013, this disorder is classified as its own separate condition under "Obsessive Compulsive and Related Disorders" and is termed "excoriation (skin-picking) disorder".

Patients may be ashamed or actively attempt to disguise their symptoms. This can make diagnosis difficult as symptoms are not always immediately obvious, or have been deliberately hidden to avoid disclosure. If the patient admits to hair pulling, diagnosis is not difficult; if patients deny hair pulling, a differential diagnosis must be pursued. The differential diagnosis will include evaluation for alopecia areata, iron deficiency, hypothyroidism, tinea capitis, traction alopecia, alopecia mucinosa, thallium poisoning, and loose anagen syndrome. In trichotillomania, a hair pull test is negative.

A biopsy can be performed and may be helpful; it reveals traumatized hair follicles with perifollicular hemorrhage, fragmented hair in the dermis, empty follicles, and deformed hair shafts (trichomalacia). Multiple catagen hairs are typically seen. An alternative technique to biopsy, particularly for children, is to shave a part of the involved area and observe for regrowth of normal hairs.

Additionally, studies have shown a high rate of concurrent autoimmunity in patients with PANS and their first degree family members further supporting a role for inflammation in PANS.

Diagnosis is by a swab of the affected area for laboratory testing. A Gram stain is performed to show Gram-positive cocci in chains. Then, the organism is cultured on blood agar with an added bacitracin antibiotic disk to show beta-hemolytic colonies and sensitivity (zone of inhibition around the disk) for the antibiotic. Culture on agar not containing blood, and then performing the catalase test should show a negative reaction for all streptococci. "S. pyogenes" is CAMP and hippurate tests negative. Serological identification of the organism involves testing for the presence of group-A-specific polysaccharide in the bacterium's cell wall using the Phadebact test.

The rapid pyrrolidonyl arylamidase (PYR) test is used for the presumptive identification of group A beta-hemolytic streptococci. GBS gives a negative finding on this test.

There is a wide range of treatments for central nervous system diseases. These can range from surgery to neural rehabilitation or prescribed medications.

The health care provider will perform a physical exam. Detailed questions will be asked about the symptoms.

If a streptococcus infection is suspected, tests will be done to confirm the infection. These include:

- Throat swab

- Anti-DNAse B blood test

- Antistreptolysin O (ASO) blood test

Further testing may include:

- Blood tests such as ESR, CBC

- MRI or CT scan of the brain

Treatment is based on a person's age. Most pre-school age children outgrow the condition if it is managed conservatively. In young adults, establishing the diagnosis and raising awareness of the condition is an important reassurance for the family and patient. Non-pharmacological interventions, including behavior modification programs, may be considered; referrals to psychologists or psychiatrists may be considered when other interventions fail. When trichotillomania begins in adulthood, it is often associated with other mental disorders, and referral to a psychologist or psychiatrist for evaluation or treatment is considered best. The hair pulling may resolve when other conditions are treated.

According to Lombroso and Scahill, 2008, "(f)ive diagnostic criteria were proposed for PANDAS: (1) the presence of a tic disorder and/or OCD consistent with DSM-IV; (2) prepubertal onset of neuropsychiatric symptoms; (3) a history of a sudden onset of symptoms and/or an episodic course with abrupt symptom exacerbation interspersed with periods of partial or complete remission; (4) evidence of a temporal association between onset or exacerbation of symptoms and a prior streptococcal infection; and (5) adventitious movements (e.g., motoric hyperactivity and choreiform movements) during symptom exacerbation". The children, originally described by Swedo "et al" in 1998, usually have dramatic, "overnight" onset of symptoms, including motor or vocal tics, obsessions, and/or compulsions. Some studies have supported acute exacerbations associated with streptococcal infections among clinically defined PANDAS subjects (Murphy and Pichichero, 2002; Giulino "et al", 2002); others have not (Luo "et al", 2004; Perrin "et al", 2004).

Concerns have been raised that PANDAS may be overdiagnosed, as a significant number of patients diagnosed with PANDAS by community physicians did not meet the criteria when examined by specialists, suggesting the PANDAS diagnosis is conferred by community physicians without conclusive evidence.

TSC typically affects multiple organ systems and manifests differently in each patient and in different stages of the life course. Drug therapy, surgery, and other interventions can be effective in managing some of the manifestations and symptoms of TSC.

In the United States, the Food and Drug Administration has approved several drugs for managing some of the major manifestations of TSC. The antiepileptic medication vigabatrin was approved in 2009 for treatment of infantile spasms and was recommended as first-line therapy for infantile spasms in children with TSC by the 2012 International TSC Consensus Conference. Adrenocorticotropic hormone was approved in 2010 to treat infantile spasms. Everolimus was approved for treatment of TSC-related tumors in the brain (subependymal giant cell astrocytoma) in 2010 and in the kidneys (renal angiomyolipoma) in 2012. Everolimus also showed evidence of effectiveness at treating epilepsy in some people with TSC. In 2017, the European Commission approved everolimus for treatment of refractory partial-onset seizures associated with TSC.

Neurosurgical intervention may reduce the severity and frequency of seizures in TSC patients. Embolization and other surgical interventions can be used to treat renal angiomyolipoma with acute hemorrhage. Surgical treatments for symptoms of lymphangioleiomyomatosis (LAM) in adult TSC patients include pleurodesis to prevent pneumothorax and lung transplantation in the case of irreversible lung failure.

Other treatments that have been used to treat TSC manifestations and symptoms include a ketogenic diet for intractable epilepsy and pulmonary rehabilitation for LAM.

Dermatophagia (from Ancient Greek "δέρμα" - skin - and "φαγεία" - eating) is a compulsion of gnawing or eating one's own skin, most commonly at the fingers. Sufferers typically bite the skin around the nails, leading to bleeding and discoloration over time. Some may consume the flesh during an episode.

Contemporary research suggests a link between impulse control disorders and obsessive–compulsive disorders, and this may be addressed in the "DSM-5", published in May 2013. Further information on OCD, other anxiety disorders, and dermatophagia and other impulse-control disorders can be found in the "DSM-IV TR".