Variations of the HLA-B gene increase the risk of developing ankylosing spondylitis, although it is not a diagnostic test. Those with the HLA-B27 variant are at a higher risk than the general population of developing the disorder. HLA-B27, demonstrated in a blood test, can occasionally help with diagnosis, but in itself is not diagnostic of AS in a person with back pain. Over 90% of people that have been diagnosed with AS are HLA-B27 positive, although this ratio varies from population to population (about 50% of African Americans with AS possess HLA-B27 in contrast to the figure of 80% among those with AS who are of Mediterranean descent).

The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), developed in Bath (UK), is an index designed to detect the inflammatory burden of active disease. The BASDAI can help to establish a diagnosis of AS in the presence of other factors such as HLA-B27 positivity, persistent buttock pain which resolves with exercise, and X-ray or MRI-evident involvement of the sacroiliac joints. It can be easily calculated and accurately assesses the need for additional therapy; a person with AS with a score of four out of a possible 10 points while on adequate NSAID therapy is usually considered a good candidate for biologic therapy.

The Bath Ankylosing Spondylitis Functional Index (BASFI) is a functional index which can accurately assess functional impairment due to the disease, as well as improvements following therapy. The BASFI is not usually used as a diagnostic tool, but rather as a tool to establish a current baseline and subsequent response to therapy.

In 1984, a joint effort led to the definition of specific classification criteria for ankylosing spondylitis, called the “Modified New York Criteria”. One of the central New York criteria was the existence of radiographically visible changes in the sacroiliac joints and/or spine, which have formed due to bone fusion, erosion and/or formation caused by the disease. Even though these criteria helped to improve uniformly define ankylosing spondylitis, such radiologic changes often only manifested several years after the first disease symptoms appeared. In order to be able to study also patients with early and less typical forms, new criteria were needed that could identify the disease already at an early stage. In 2009 the Modified New York criteria were extended by a broad set of new classification criteria that aimed to classify patients based on the presence of typical spondyloarthritis disease features. These included inflammatory back pain, family history for axial spondyloarthritis, response to treatment with nonsteroidal anti-inflammatory drugs (NSAIDs), past history of or current inflammation in the joints (arthritis), tendon-bone attachment of the heel (enthesitis), or eyes (uveitis), bowel (inflammatory bowel disease), skin (psoriasis) or signs of elevated inflammation (C-reactive protein and erythrocyte sedimentation rate. Important parts of the ASAS axSpA criteria is the biomarker HLA-B27 and magnetic resonance imaging (MRI). The criteria can only be applied in people that have chronic back pain (at least 3 months duration) started before the age of 45 years and only in those patients that already have a diagnosis of axial SpA. Since the disease ankylosing spondylitis was still defined by the Modified New York criteria of 1984, there was the need to find a new disease term that would also include the less severe forms or early onset of ankylosing spondylitis. This expression was found in the umbrella term axial spondyloarthritis. The 2009 classification criteria are called the ASAS (Assessment of SpondyloArthritis international Society) axial spondayloarthritis criteria.

Axial spondyloarthritis can be divided into two classes:

1. Non-radiographic axial spondyloarthritis (nr-axSpA): This term encompasses both, the early disease stage of ankylosing spondylitis, in which no radiographic changes are visible yet, as well as less severe forms of ankylosing spondylitis.

2. Radiographic axial spondyloarthritis:Synonym for ankylosing spondylitis. This class is termed radiographic axial spondyloarthritis due to the unambiguous diagnosis through radiographic changes in the sacroiliac joints and/or spine.

Assessment of Spondylarthritis International Society (ASAS criteria) is used for classification of axial spondyloarthritis (to be applied for patients with back pain greater than or equal to 3 months and age of onset less than 45 years). It is of two broad types:

1. Sacroiliitis on imaging plus 1 SpA feature, or

2. HLA-B27 plus 2 other SpA features

Sacroiliitis on imaging:

- Active (acute) inflammation on MRI highly suggestive of SpA-associated sacroiliitis and/or

- Definite radiographic sacroiliitis

SpA features:

- Inflammatory back pain

- Arthritis

- Enthesitis

- Anterior uveitis

- Dactylitis

- Psoriasis

- Crohn's disease or ulcerative colitis

- Good response to NSAIDs

- Family history of SpA

- HLA-B27

- Elevated CRP

Worldwide prevalence of spondyloarthropathy is approximately 1.9%.

Sacroiliitis can be somewhat difficult to diagnose because the symptoms it manifests can also be caused by other, more common, conditions. If a physician suspects sacroiliitis, they will typically begin their diagnosis by performing a physical exam. Since the condition is axial, they can often pinpoint the affected joint by putting pressure on different places within the legs, hips, spine and buttocks. They may also ask a patient to perform some stretches that will put gentle stress on the sacroiliac joints.

X-rays, MRIs and other medical imaging tests can be used to show signs of inflammation and damage within the SI joints. Typically, a spine specialist will order a medical imaging test if they suspect ankylosing spondylitis or another form of arthritis to be the primary cause of inflammation and pain.

Treatment of sacroiliitis can vary depending on the severity of the condition and the amount of pain the patient is currently experiencing. However, it typically falls into one of two categories non-surgical and surgical:

Poor prognostic factors include,

- Persistent synovitis

- Early erosive disease

- Extra-articular findings (including subcutaneous rheumatoid nodules)

- Positive serum RF findings

- Positive serum anti-CCP autoantibodies

- Carriership of HLA-DR4 "Shared Epitope" alleles

- Family history of RA

- Poor functional status

- Socioeconomic factors

- Elevated acute phase response (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP])

- Increased clinical severity.

RA reduces lifespan on average from three to twelve years. According to the UK's National Rheumatoid Arthritis Society, Young age at onset, long disease duration, the concurrent presence of other health problems (called co-morbidity), and characteristics of severe RA—such as poor functional ability or overall health status, a lot of joint damage on x-rays, the need for hospitalisation or involvement of organs other than the joints—have been shown to associate with higher mortality". Positive responses to treatment may indicate a better prognosis. A 2005 study by the Mayo Clinic noted that RA sufferers suffer a doubled risk of heart disease, independent of other risk factors such as diabetes, alcohol abuse, and elevated cholesterol, blood pressure and body mass index. The mechanism by which RA causes this increased risk remains unknown; the presence of chronic inflammation has been proposed as a contributing factor. It is possible that the use of new biologic drug therapies extend the lifespan of people with RA and reduce the risk and progression of atherosclerosis. This is based on cohort and registry studies, and still remains hypothetical. It is still uncertain whether biologics improve vascular function in RA or not. There was an increase in total cholesterol and HDLc levels and no improvement of the atherogenic index.

There is no definitive test to diagnose psoriatic arthritis. Symptoms of psoriatic arthritis may closely resemble other diseases, including rheumatoid arthritis. A rheumatologist (a doctor specializing in autoimmune diseases) may use physical examinations, health history, blood tests and x-rays to accurately diagnose psoriatic arthritis.

Factors that contribute to a diagnosis of psoriatic arthritis include the following:

- Psoriasis in the patient, or a family history of psoriasis or psoriatic arthritis.

- A negative test result for rheumatoid factor, a blood factor associated with rheumatoid arthritis.

- Arthritis symptoms in the distal Interphalangeal articulations of hand (the joints closest to the tips of the fingers). This is not typical of rheumatoid arthritis.

- Ridging or pitting of fingernails or toenails (onycholysis), which is associated with psoriasis and psoriatic arthritis.

- Radiologic images demonstrating degenerative joint changes.

Other symptoms that are more typical of psoriatic arthritis than other forms of arthritis include enthesitis (inflammation in the Achilles tendon (at the back of the heel) or the plantar fascia (bottom of the feet)), and dactylitis (sausage-like swelling of the fingers or toes).

Several conditions can mimic the clinical presentation of psoriatic arthritis including rheumatoid arthritis, osteoarthritis, reactive arthritis, gouty arthritis, systemic lupus erythematosus, and inflammatory bowel disease-associated arthritis. In contrast to psoriatic arthritis, rheumatoid arthritis tends to affect the proximal joints (e.g., the metacarpophalangeal joints), involves a greater number of joints than psoriatic arthritis, and affect them symmetrically. Involvement of the spinal joints is more suggestive of psoriatic arthritis than rheumatoid arthritis. Osteoarthritis shares certain clinical features with psoriatic arthritis such as its tendency to affect multiple distal joints in an asymmetric pattern. Unlike psoriatic arthritis, osteoarthritis does not typically involve inflammation of the sacroiliac joint. Psoriatic arthritis sometimes affects only one joint and is sometimes confused for gout or pseudogout when this happens.

Inflammatory arthritis can be disabling to the point where people with the diseases can lose their jobs, which can cause psychological distress. Because it is typically progressive, those who lose their jobs are unlikely to re-enter the workforce after leaving due to their diagnosis. Programs now aim to retain those with inflammatory arthritis by preventing work-related injuries and by making necessary accommodations in the workplace. A 2014 Cochrane review found low-quality evidence that work focused interventions, including counseling, education, advocacy, and occupational medicine consultations, were effective in retaining workers with inflammatory arthritis.

The diagnosis process might include a physician who tests that the movement, strength, and sensation of the arms and legs are normal. The spine is examined for its range of motion and any pain that may arise from movement. Blood work might be utilized in addition to radiographic imaging in order to identify spinal cord diseases. Basic imaging techniques, which includes x-ray imaging, can reveal degenerative changes of the spine, while more advanced imaging techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI), can allow visualization of more detailed anatomical structures, including that of the associated nerves and muscles. The most detailed and specific testing is electrodiagnostic, which helps to uncover whether the appropriate electrical signals are being sent to each muscle from the correlate nerves. This aids in localizing a problem's source. There are risks to be considered with any diagnostic testing. For example, in the case of CT imaging, there is obvious benefit over x-ray in that a more thorough picture of the anatomy is exposed, but there is a trade-off in that CT has around a 10-fold increased radiation exposure; alternatively, while MRI provides highly detailed imaging of the anatomy with the benefit of no radiation exposure to the patient, the high cost of this test must be taken into account.

The worldwide prevalence of inflammatory arthritis is approximately 3%. Rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and undifferentiated spondyloarthritis are the most common subtypes of inflammatory arthritis. The diseases occur most commonly in the 30-40 age group.

If one’s symptoms are mild, treatments like Massage, Exercise, and Stress management will suffice in reducing pain and pressure, but those with more severe symptoms are told to undergo unique therapies based on their exact situation. These patients most likely will have their postures and spine alignment fixed, and/or treatments like electrical stimulation may be used to help in reducing pain and aid in flexibility. Medicine, epidural injections and surgeries are also implemented to treat such a disorder.

Diagnosis can be established using plain film x-rays as well as CT scan of the neck/cervical spine. Children with Down's syndrome have inherently lax ligaments making them susceptible to this condition. In select cases, these children may require pre-operative imaging to assess the risk for complications after procedures such as adenoidectomy.

Treatment includes anti-inflammatory medications and immobilization of the neck in addition to treatment of the offending infectious cause (if any) with appropriate antibiotics. Early treatment is crucial to prevent long-term sequelae. Surgical fusion may be required for residual instability of the joint.

Conventional radiography is usually the initial assessment tool when a calcaneal fracture is suspected. Recommended x-ray views are (a) axial, (b) anteroposterior, (c) oblique and (d) views with dorsiflexion and internal rotation of the foot. However, conventional radiography is limited for visualization of calcaneal anatomy, especially at the subtalar joint. A CT scan is currently the imaging study of choice for evaluating calcaneal injury and has substituted conventional radiography in the classification of calcaneal fractures. Axial and coronal views are obtained for proper visualization of the calcaneus, subtalar, calcaneocuboid and talonavicular joints.

In all injuries to the tibial plateau radiographs (commonly called x-rays) are imperative. Computed tomography scans are not always necessary but are sometimes critical for evaluating degree of fracture and determining a treatment plan that would not be possible with plain radiographs. Magnetic Resonance images are the diagnositic modality of choice when meniscal, ligamentous and soft tissue injuries are suspected. CT angiography should be considered if there is alteration of the distal pulses or concern about arterial injury.

Treatment is aimed at achieving a stable, aligned, mobile and painless joint and to minimize the risk of post-traumatic osteoarthritis. To achieve this operative or non-operative treatment plans are considered by physicians based on criteria such as patient characteristics, severity, risk of complications, fracture depression and displacement, degree of injury to ligaments and menisci, vascular and neurological compromise.

For early management, traction should be performed early in ward. It can either be Skin Traction or Skeletal Traction. Depends on the body weight of patient and stability of the joint. Schantz pin insertion over the Calcaneum should be done from Medial to lateral side.

Later when condition is stable. Definitive plan would be Buttress Plating and Lag Screw fixation.

In order to qualify a patient's condition as BSS, the bending angle must be greater than 45 degrees. While the presence of the condition is very easy to note, the cause of the condition is much more difficult to discern. Conditions not considered to be BSS include vertebral fractures, previously existing conditions, and ankylosing spondylitis. Lower-back CT scans and MRIs can typically be used to visualize the cause of the disease. Further identification of the cause can be done by histochemical or cellular analysis of muscle biopsy.

Camptocormia is becoming progressively found in patients with Parkinson's disease.

The diagnosis of Parkinson's-associated camptocormia includes the use of imaging of the brain and the spinal cord, along with electromyography or muscle biopsies.

Muscle biopsies are also a useful tool to diagnose camptocormia. Muscle biopsies found to have variable muscle fiber sizes and even endomysial fibrosis may be markers of bent spine syndrome. In addition, disorganized internal architecture and little necrosis or regeneration is a marker of camptocormia.

Patients with camptocormia present with reduced strength and stooped posture when standing due to weakened paraspinous muscles (muscles parallel to the spine). Clinically, limb muscles show fatigue with repetitive movements. Paraspinous muscles undergo fat infiltration. Electromyography may be used as well in diagnosis. On average, the paraspinous muscles of affected individuals were found to be 75% myopathic, while limb muscles were 50% percent myopathic. Creatine kinase activity levels in skeletal muscle are a diagnostic indicator that can be identifiable through blood tests.

Evaluating soft-tissue involvement is the most important aspect of the clinical examination because of its association with patient outcome. Skin blisters may become infected if medical attention is delayed, which can lead to necrotizing fasciitis or osteomyelitis, causing permanent damage to muscle or bone. Ligament and tendon involvement should also be explored. Achilles tendon injury can be seen with posterior (Type C) fractures. Since calcaneal fractures are related to falls from height, other concomitant injuries should be evaluated. Vertebral compression fractures occur in approximately 10% of these patients. A trauma-focused clinical approach should be implemented; tibial, knee, femur, hip, and head injuries should be ruled out by means of history and physical exam.

Outbreaks may be measurable clinically by elevated levels of alkaline phosphatase and bone-specific alkaline phosphatase.

Thin cut (2-3mm) CT scan with axial and coronal view is the optimal study of choice for orbital fractures.

Plain radiographs, on the other hand, do not sensitively capture blowout fractures. On Water's view radiograph, polypoid mass can be observed hanging from the floor into the maxillary antrum, classically known as teardrop sign, as it usually is in shape of a teardrop. This polypoid mass consists of herniated orbital contents, periorbital fat and inferior rectus muscle. The affected sinus is partially opacified on radiograph. Air-fluid level in maxillary sinus may sometimes be seen due to presence of blood. Lucency in orbits (on a radiograph) usually indicate orbital emphysema.