An OI diagnosis can be confirmed through DNA or collagen testing, but in many cases the occurrence of bone fractures with little trauma and the presence of other clinical features such as blue sclera are sufficient for a diagnosis. A skin biopsy can be performed to determine the structure and quantity of type I collagen. DNA testing can confirm the diagnosis, however, it cannot exclude it because not all mutations causing OI are known and/or tested for. OI type II is often diagnosed by ultrasound during pregnancy, where already multiple fractures and other characteristic features may be present. Relative to control, OI cortical bone shows increased porosity, canal diameter, and connectivity in micro-computed tomography.

An important differential diagnosis of OI is child abuse, as both may present with multiple fractures in various stages of healing. Differentiating them can be difficult, especially when no other characteristic features of OI are present. Other differential diagnoses include rickets, osteomalacia, and other rare skeletal syndromes.

Exact diagnosis remains widely built on precise history taking, with the characteristic clinical and radiographic skeletal features. Genetic diagnosis is based on DNA sequencing. Because plasma COMP levels are significantly reduced in patients with COMP mutations, such as pseudoachondroplasia, measuring plasma COMP levels has become a reliable means of diagnosing this and pathopysiologically similar disorders.

Diagnosis should be based on the clinical and radiographic findings and a genetic analysis can be assessed.

X-Ray

Bubbly lytic lesion / Ground glass

Imaging tests. Computerized tomography or magnetic resonance imaging scans may be used to determine how extensively your bones are affected.

Bone scan. This test uses radioactive tracers, which are injected into your bloodstream. The damaged parts of your bones take up more of the tracers, which show up more brightly on the scan.

Biopsy. This test uses a hollow needle to remove a small piece of the affected bone for laboratory analysis.

Accurate assessment of plain radiographic findings remains an important contributor to diagnosis of pseudoachondroplasia. It is noteworthy that vertebral radiographic abnormalities tend to resolve over time. Epiphyseal abnormalities tend to run a progressive course. Patients usually suffer early-onset arthritis of hips and knees. Many unique skeletal radiographic abnormalities of patients with pseudoachondroplasia have been reported in the literature.

- Together with rhizomelic limb shortening, the presence of epiphyseal-metaphyseal changes of the long bones is a distinctive radiologic feature of pseudoachondroplasia.

- Hypoplastic capital femoral epiphyses, broad short femoral necks, coxa vara, horizontality of acetabular roof and delayed eruption of secondary ossification center of os pubis and greater trochanter.

- Dysplastic/hypoplastic epiphyses especially of shoulders and around the knees.

- Metaphyseal broadening, irregularity and metaphyseal line of ossification. These abnormalities that are typically encountered in proximal humerus and around the knees are collectively known as “rachitic-like changes”.

- Radiographic lesions of the appendicular skeleton are typically bilateral and symmetric.

- Oval shaped vertebrae with anterior beak originating and platyspondyly demonstrated on lateral radiographs of the spine.

- Normal widening of the interpedicular distances caudally demonstrated on anteroposterior radiographs of the dorsolumbar region. This is an important differentiating feature between pseudoachondroplasia and achondroplasia.

- Odontoid hypoplasia may occur resulting in cervical instability.

A combination of medical tests are used to diagnosis kniest dysplasia. These tests can include:

- Computer Tomography Scan(CT scan) - This test uses multiple images taken at different angles to produce a cross-sectional image of the body.

- Magnetic Resonance Imaging (MRI) - This technique proves detailed images of the body by using magnetic fields and radio waves.

- EOS Imaging - EOS imaging provides information on how musculoskeletal system interacts with the joints. The 3D image is scanned while the patient is standing and allows the physician to view the natural, weight-bearing posture.

- X-rays - X-ray images will allow the physician to have a closer look on whether or not the bones are growing abnormally.

The images taken will help to identify any bone anomalies. Two key features to look for in a patient with kniest dysplasia is the presence of dumb-bell shaped femur bones and coronal clefts in the vertebrae. Other features to look for include:

- Platyspondyly (flat vertebral bodies)

- Kyphoscoliosis (abnormal rounding of the back and lateral curvature of the spine)

- Abnormal growth of epiphyses, metaphyses, and diaphysis

- Short tubular bones

- Narrowed joint spaces

Genetic Testing - A genetic sample may be taken in order to closely look at the patient's DNA. Finding an error in the COL2A1 gene will help identify the condition as a type II chondroldysplasia.

Because this genetic anomaly is genetically linked, genetic counseling may be the only way to decrease occurrences of Cherubism. The lack of severe symptoms in the parents may be the cause of failure in recognizing the disorder. The optimal time to be tested for mutations is prior to having children. The disorder results from a genetic mutation, and this gene has been found to spontaneously mutate. Therefore, there may be no prevention techniques available.

More than 1 in 2 people with OI also have dentinogenesis imperfecta (DI) - a congenital disorder of formation of dentine. Dental treatment may pose as a challenge as a result of the various deformities, skeletal and dental, due to OI. Children with OI should go for a dental check-up as soon as their teeth erupt, this may minimize tooth structure loss as a result of abnormal dentine, and they should be monitored regularly to preserve their teeth and oral health.

Achondroplasia can be detected before birth by prenatal ultrasound. A DNA test can be performed before birth to detect homozygosity, wherein two copies of the mutant gene are inherited, a lethal condition leading to stillbirths. Clinical features include megalocephaly, short limbs, prominent forehead, thoracolumbar kyphosis and mid-face hypoplasia. Complications like dental malocclusion, hydrocephalus and repeated otitis media can be observed. The risk of death in infancy is increased due to the likelihood of compression of the spinal cord with or without upper airway obstruction.

Osteogenesis imperfecta is a rare condition in which bones break easily. There are multiple genetic mutations in different genes for collagen that may result in this condition. It can be treated with some drugs to promote bone growth, by surgically implanting metal rods in long bones to strengthen them, and through physical therapy and medical devices to improve mobility.

The chemical imbalance is usually diagnosed when dental abnormalities are found. These abnormalities include premature deciduous teeth and abnormal growth of permanent teeth due to displacement by cysts and lesions. The only definite way to correctly diagnose the condition is by sequence analysis of the SH3BP2 gene. The gene has been found to have missense mutation in exon 9. Initial study of the patient is usually conducted using x-ray and CT scans. Neurofibromatosis may resemble Cherubism and may accompany the condition. Genetic testing is the final diagnosis tool.

Osteochondromas are often asymptomatic and may not cause any kind of discomfort. They are often found accidentally when an X-ray is done for an unrelated reason.

- X-rays are the first tests performed that characterize a lesion. They show a clear picture of dense structures of bones, and will also indicate bone growth pertaining to osteochondroma.

- Computed Tomography (CT) scan can identify the bony lesion in great details and show the presence of calcification. These tests also provide great details, especially in soft tissues with the aide of cross-sectional images.

- Magnetic Resonance Imaging (MRI) is the most accurate method for detecting bone masses in symptomatic cases to depict precise morphology of a tumor. It is used to verify if the palpable mass is continuous with the cortex of the affected bone and to differentiate an osteochondroma from other lesions on the surface of the bone. MRI can also be used to look for cartilage on the surface of tumor and can depict any vascular complications caused by the tumor. An MRI can identify tumors of the spinal column and is often used to diagnose low grade osteosarcoma.

- Ultrasound is done if aneurysms or pseudoaneurysms and venous or arterial thrombosis is suspected. Ultrasound is an accurate method for examining the cartilaginous cap of the osteochondroma. It is also a way of pinpointing bursitis. However, it cannot be used to predict if the growth of tumor is inward in regards to the cap.

- Angiography is used to detect vascular lesions caused by osteochondroma due to ossified cartilaginous cap. It is also used to characterize malignant transformation lesions through neovascularity.

- Clinical testing such as sequence analysis can be done of the entire coding regions of both "EXT1" and "EXT2" to detect mutations.

- A biopsy of the tissue sample of the tumor can also be taken to check for cancer.

Tests for osteochondroma can also identify diseases such as secondary peripheral chondrosarcoma and Multiple osteochondromatosis. In large, secondary chondrosarcoma arises at the site of osteochondroma due to increased thickness of the cartilage cap indicating potential malignant transformation. The symptoms of multiple osteochondromatosis are similar to solitary osteochondroma, but they are often more severe. Painless bumps can arise at the site of tumor and pain and other discomforts can also take place if pressure is put on the soft tissues, nerves, or blood vessels. Dysplasia Epiphysealis Hemimelica (DEH) or Trevor's disease and metachondromatosis (MC) are considered differential diagnosis of both solitary and hereditary osteochondromas. DEH is described as a type of over growth at one or more epiphyses. Similar to osteochondroma, DEH is diagnosed prior to 15 years of age and the growth of lesions end at puberty, when the growth plates close. Metachondromatosis is a rare disorder that exhibit symptoms of both multiple osteochondromas and enchondromas in children and is also inherited in autosomal dominant mode.

Treatment in fibrous dysplasia is mainly palliative, and is focused on managing fractures and preventing deformity. There are no medications capable of altering the disease course. Intravenous bisphosphonates may be helpful for treatment of bone pain, but there is no clear evidence that they strengthen bone lesions or prevent fractures. Surgical techniques that are effective in other disorders, such as bone grafting, curettage, and plates and screws, are frequently ineffective in fibrous dysplasia and should be avoided. Intramedullary rods are generally preferred for management of fractures and deformity in the lower extremities. Progressive scoliosis can generally be managed with standard instrumentation and fusion techniques. Surgical management in the craniofacial skeleton is complicated by frequent post-operative FD regrowth, and should focus on correction of functional deformities. Prophylactic optic nerve decompression increases the risk of vision loss and is contraindicated.

Managing endocrinopathies is a critical component of management in FD. All patients with fibrous dysplasia should be evaluated and treated for endocrine diseases associated with McCune–Albright syndrome. In particular untreated growth hormone excess may worsen craniofacial fibrous dysplasia and increase the risk of blindness. Untreated hypophosphatemia increases bone pain and risk of fractures.

A skeletal survey is useful to confirm the diagnosis of achondroplasia. The skull is large, with a narrow foramen magnum, and relatively small skull base. The vertebral bodies are short and flattened with relatively large intervertebral disk height, and there is congenitally narrowed spinal canal. The iliac wings are small and squared, with a narrow sciatic notch and horizontal acetabular roof. The tubular bones are short and thick with metaphyseal cupping and flaring and irregular growth plates. Fibular overgrowth is present. The hand is broad with short metacarpals and phalanges, and a trident configuration. The ribs are short with cupped anterior ends. If the radiographic features are not classic, a search for a different diagnosis should be entertained. Because of the extremely deformed bone structure, people with achondroplasia are often "double jointed".

The diagnosis can be made by fetal ultrasound by progressive discordance between the femur length and biparietal diameter by age. The trident hand configuration can be seen if the fingers are fully extended."

Another distinct characteristic of the syndrome is thoracolumbar gibbus in infancy.

The disorder is progressive, with the ultimate severity of symptoms often depending on age of onset. In severe cases amputation has been performed when conservative measures such as physical therapy and regional anesthetics have been ineffective.

Because kniest dysplasia can affect various body systems, treatments can vary between non-surgical and surgical treatment. Patients will be monitored over time, and treatments will be provided based on the complications that arise.

"Osteosclerosis", an elevation in bone density, is normally detected on an X-ray as an area of whiteness, and is where the bone density has significantly increased. Localized osteosclerosis can be caused by injuries that compress the bone, by osteoarthritis, and osteoma.

Symptomatic individuals should be seen by an orthopedist to assess the possibility of treatment (physiotherapy for muscular strengthening, cautious use of analgesic medications such as nonsteroidal anti-inflammatory drugs). Although there is no cure, surgery is sometimes used to relieve symptoms. Surgery may be necessary to treat malformation of the hip (osteotomy of the pelvis or the collum femoris) and, in some cases, malformation (e.g., genu varum or genu valgum). In some cases, total hip replacement may be necessary. However, surgery is not always necessary or appropriate.

Sports involving joint overload are to be avoided, while swimming or cycling are strongly suggested. Cycling has to be avoided in people having ligamentous laxity.

Weight control is suggested.

The use of crutches, other deambulatory aids or wheelchair is useful to prevent hip pain. Pain in the hand while writing can be avoided using a pen with wide grip.

Some tests which detect cancer could be called "screening for epithelial dysplasia". The principle behind these tests is that physicians expect dysplasia to occur at the same rate in a typical individual as it would in many other people. Because of this, researchers design screening recommendations which assume that if a physician can find no dysplasia at certain time, then doing testing before waiting until new dysplasia could potentially develop would be a waste of medical resources for the patient and the healthcare provider because the chances of detecting anything is extremely low.

Some examples of this in practice are that if a patient whose endoscopy did not detect dysplasia on biopsy during screening for Barrett's esophagus, then research shows that there is little chance of any test detecting dysplasia for that patient within three years.

Individuals at average-risk for colorectal cancer should have another screening after ten years if they get a normal result and after five years if they have only one or two adenomatous polyps removed.

The frequency of this disorder is unknown, but it is very rare. Only a few families with the condition have been reported.

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.

Spondyloperipheral dysplasia is an autosomal dominant disorder of bone growth. The condition is characterized by flattened bones of the spine (platyspondyly) and unusually short fingers and toes (brachydactyly). Some affected individuals also have other skeletal abnormalities, short stature, nearsightedness (myopia), hearing loss, and mental retardation. Spondyloperipheral dysplasia is a subtype of collagenopathy, types II and XI.

Platyspondylic lethal skeletal dysplasia, Torrance type is a severe disorder of bone growth. People with this condition have very short arms and legs, a small chest with short ribs, underdeveloped pelvic bones, and unusually short fingers and toes (brachydactyly). This disorder is also characterized by flattened spinal bones (platyspondyly) and abnormal curvature of the spine (lordosis).

As a result of these serious skeletal problems, many infants with platyspondylic lethal skeletal dysplasia, Torrance type are born prematurely, are stillborn, or die shortly after birth from respiratory failure. A few affected people with milder signs and symptoms have lived into adulthood, however.

This condition is one of a spectrum of skeletal disorders caused by mutations in the "COL2A1" gene. This gene provides instructions for making a protein that forms type II collagen. This type of collagen is found mostly in cartilage and in the clear gel that fills the eyeball (the vitreous). It is essential for the normal development of bones and other tissues that form the body's supportive framework (connective tissues).

Mutations in the "COL2A1" gene interfere with the assembly of type II collagen molecules, resulting in a reduced amount of this type of collagen in the body. Instead of forming collagen molecules, the abnormal "COL2A1" protein builds up in cartilage cells (chondrocytes). These changes disrupt the normal development of bones and other connective tissues, leading to the skeletal abnormalities characteristic of platyspondylic lethal skeletal dysplasia, Torrance type.

This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In some cases, an affected person inherits the mutation from one affected parent. Other cases may result from new mutations in the gene. These cases occur in people with no history of the disorder in their family.

Affected infants have short arms and legs, a small chest with short ribs, and underdeveloped lungs. The spinal bones (vertebrae) in the neck and part of the pelvis (the sacrum) do not harden, or ossify, properly. The face appears flat and oval-shaped, with widely spaced eyes, a small chin, and, in some cases, an opening in the roof of the mouth called a cleft palate. The abdomen is enlarged, and excess fluid may build up in the body before birth (a condition called hydrops fetalis).

As a result of these serious health problems, infants are usually premature and stillborn or die shortly after birth from respiratory failure. Some infants have lived for a time, however, with intensive medical support. Babies who live past the newborn period are usually reclassified as having spondyloepiphyseal dysplasia congenita, a related disorder on the spectrum of abnormal bone growth.

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.