≤11 ribs is associated with a number of congenital abnormalities and skeletal dysplasias, including:
Down syndrome (trisomy 21)
asphyxiating thoracic dysplasia (Jeune syndrome)
short rib polydactyly syndromes
chromosome 1q21.1 deletion...
18q-deletion syndrome is a rare chromosomal anomaly where there is a deletion of part of the long arm of chromosome 18. Associated symptoms and findings vary widely, as do their severity. Characteristic clinical features include short stature, intellectual disability, hypotonia, facial and dista...
Accessory navicular syndrome occurs when a type II accessory navicular becomes painful due to movement across the pseudo-joint between the ossicle and the navicular bone.
It can be inferred on musculoskeletal ultrasound if a patient's pain is located at a type...
Achondrogenesis refers to a group of rare and extreme skeletal dysplasias.
The estimated incidence is 1:40,000 with no recognised gender predilection.
It is classified as an osteochondrodysplasia, meaning deficiency of both bone and cartilage development.
Acrocephalosyndactyly syndromes (ACS) are a rare group of disorders collectively characterised by:
calvarial anomalies, e.g. craniosynostoses
digital anomalies, e.g. syndactyly
While there can be some overlap in features, they can be primarily classified into the following maj...
Acrodysostosis is a rare skeletal dysplasia characterised by growth retardation, nasal hypoplasia, brachydactyly, midfacial deficiency, intellectual disability and deafness.
Most cases are sporadic. Few cases with autosomal dominant transmission have been reported. It is believed to ...
Acute compartment syndrome is a limb and life-threatening surgical emergency. It is a painful condition caused by increased intracompartmental pressure, compromising perfusion and resulting in muscle and nerve damage within that compartment.
Acute compartment syndrome is more comm...
Adductor canal syndrome (also known as adductor canal compression syndrome) is a rare, non-atherosclerotic cause of arterial occlusion and limb ischaemia 1. There is compression of the superficial femoral artery (SFA) in the adductor canal.
External compression of the superficial ...
Amniotic band syndrome (ABS) comprises of a wide spectrum of abnormalities, all of which result from entrapment of various fetal body parts in a disrupted amnion. Due to the randomness of entrapment, each affected individual has the potential to form a unique deficit.
Anterior ankle impingement (AAI) syndrome is the result of chronic repetitive trauma with impingement of the anterior tibia against the talus.
Clinical features of anterior ankle impingement syndrome include painful and limited dorsiflexion and anterior joint line swellin...
Antley-Bixler syndrome (ABS), also known as trapezoidocephaly-synostosis syndrome, is a rare autosomal dominant or recessive condition characterised by craniosynostosis and extra-cranial synostoses. Mid-facial hypoplasia is also common.
It is a very rare condition with only 50 cas...
Apert syndrome (also known as type I acrocephalosyndactyly) is a syndrome that is predominantly characterised by skull and limb malformations.
The estimated incidence is 1 case per 65-80,000 pregnancies.
increased paternal age has been proposed 6
Atelosteogenesis refers to a heterogeneous group of lethal skeletal dysplasias that are characterised by aplasia/hypoplasia of the humeri, femora and spine.
atelosteogenesis type I (boomerang dysplasia)
atelosteogenesis type II
atelosteogenesis type III 4
Bannayan–Riley–Ruvalcaba syndrome (BRRS or BRR syndrome) is a very rare autosomal dominant hamartomatous disorder caused by a mutation in the PTEN gene. It is considered in the family of hamartomatous polyposis syndrome.
There are no formal diagnostic criteria for this disease, but characterist...
Bannayan-Zonana syndrome, also known as Bannayan-Riley-Ruvalcaba syndrome, is a rare hamartomatous disorder.
Male predominance is reported 1.
Bannayan-Zonana syndrome is characterised by:
Other findings tha...
Bertolotti syndrome refers to the association between lumbosacral transitional vertebrae and low back pain.
Although it may be a consideration in younger patients, the entity is considered controversial and has been both supported and disputed since the Italian radiologist Mario Bertolotti (187...
Bone marrow oedema syndrome refers to a group of transient, self-limiting clinical entities of unknown cause, which are associated with the presence of bone marrow oedema pattern.
These conditions include:
transient osteoporosis of the hip
bone marrow oedema syndrome of the foot and ankle
Bone marrow oedema syndrome of the foot and ankle, also known as transient bone marrow oedema syndrome of the foot and ankle, refers to the presence of self-limited, patchy bone marrow T2 hyperintensities in the bones of the ankle and/or foot of unknown aetiology. It is related to transient oste...
Branchio-oculo-facial syndrome (BOFS) is a very rare autosomal dominant genetic disorder that is characterised clinically by abnormalities affecting the eyes, craniofacial structures, and branchial sinuses.
More than 80 cases have been reported in the global literature since its f...
Buschke-Ollendorff syndrome (BOS), also known as disseminated dermatofibrosis lenticularis 2, comprises of osteopoikilosis associated with disseminated connective tissue and cutaneous yellowish naevi, predominantly on the extremities and trunk 1. Recent genetic work has linked this syndrome to...
Caffey disease or infantile cortical hyperostosis is a largely self-limiting disorder which affects infants. It causes bone changes, soft-tissue swelling, and irritability.
It is distinct from physiological periostitis which can be seen involving the diaphyses of the tibiae, humeri, and femora ...
Campomelic dwarfism, also known as campomelic dysplasia, is a rare form of skeletal dysplasia.
Campomelic dwarfism is rare with an estimated incidence of ~1:200,000 births.
genital malformations: may be present in ~66% of patients 6
Camptocormia (bent spine syndrome or cyphose hystérique) is a rare syndrome characterised by involuntary flexion of the thoracolumbar spine with weight-bearing which reduces when laying down, and is due to isolated atrophy of the paraspinal muscles.
In a small case series (n=16), ...
Camptodactyly arthropathy coxa vara pericarditis (CACP) syndrome is a rare condition principally characterised by
congenital or early-onset camptodactyly and childhood-onset non-inflammatory arthropathy
coxa vara deformity or other dysplasia associated with progressive hip disease
Camurati-Engelmann disease, also known as progressive diaphyseal dysplasia, is a rare autosomal dominant sclerosing bone dysplasia. It begins in childhood and follows a progressive course.
Common symptoms include extremity pain, muscle weakness, cranial nerve impairment a...
Carpal tunnel syndrome results from compression of the median nerve within the carpal tunnel. It is a cause of significant disability and is one of three common median nerve entrapment syndromes, the other two being anterior interosseous nerve syndrome and pronator teres syndrome.
Carpenter syndrome, also called acrocephalopolysyndactyly type II (ACPS type II) is an extremely rare autosomal recessive congenital disorder.
It is characterised by a number of features which include:
Chronic recurrent multifocal osteomyelitis (CRMO) is an idiopathic inflammatory bone disorder seen primarily in children and adolescents. It is often a diagnosis of exclusion once underlying infection and neoplasia have been ruled out. However, there are some cases in which lesion location and m...
Clasp-knife deformity is relatively common congenital anomaly found at the lumbosacral junction.
When a clasp-knife deformity is accompanied by pain on extension secondary to protrusion of the enlarged spinous process (knife blade) into the sacral spinal canal, it is called clasp-k...
Cobb syndrome, also called cutaneous vertebral medullary angiomatosis, or spinal arteriovenous metameric syndrome, consists of the presence of a vascular naevus with a spinal vascular malformation of the same body somite (metamere).
The importance of this syndrome is the recognition that cutan...
Complex regional pain syndrome (CRPS), also known as Sudeck atrophy, is a condition which can affect the extremities in a wide clinical spectrum. CRPS is principally a clinical diagnosis - no one imaging study is sensitive or specific to rule in or rule out the syndrome.
Conus medullaris syndrome is caused by an injury or insult to the conus medullaris and lumbar nerve roots. It is a clinical subset of spinal cord injury syndromes. Injuries at the level of T12 to L2 vertebrae are most likely to result in conus medullaris syndrome.
Cowden syndrome, also known as multiple hamartoma syndrome, is characterised by multiple hamartomas throughout the body and increased risk of several cancers.
Type 2 segmental Cowden syndrome is the association of Cowden syndrome with a Cowden naevus when it is considered a type of...
CREST syndrome (also known as. limited systemic sclerosis or limited scleroderma) is a variant of progressive systemic sclerosis (PSS) and stands for
C - calcinosis
R - Raynaud phenomenon
E - oesophageal dysmotility
S - sclerodactyly
T - telangiectasia
Crouzon syndrome is rare disorder characterised by premature craniosynostoses.
abnormal calvarial shape: in severe case can give a "cloverleaf skull"
shallow orbits with exophthalmos
mid facial hypoplasia
It carries an autosomal dominant...
Cubital tunnel syndrome is a type of ulnar nerve compression neuropathy due to pathological compression of the ulnar nerve along its course within the cubital tunnel.
The compression of the ulnar nerve at the elbow is the second most common peripheral neuropathy of the upper extre...
Cuboid syndrome is a cause of lateral midoot pain, believed to result from abnormal articulation of the cuboid with the calcaneus (calcaneocuboid joint).
Cuboid syndrome presents with lateral foot pain and swelling, often diffuse and similar to an ankle (ligament) sprain ...
Currarino-Silverman syndrome, also known as pectus carinatum type 2 deformity, is a rare disorder.
Patients present with a high carinate chest deformity due to a premature fusion of the manubriosternal joint and sternal ossification centres. Congenital heart diseases have...
Cyriax syndrome, also known as slipping rib syndrome, occurs when hypermobility of the rib cartilage of the lower ribs slips and moves, leading to pain in lower chest or upper abdomen 1.
This condition may occur at any age, but is reportedly more common in middle-aged adults, and ...
The distal intersection syndrome relates to tenosynovitis of the extensor pollicis longus (EPL) tendon (3rd extensor compartment), where it crosses the extensor carpi radialis longus (ECRL) and brevis (ECRB) tendons (2nd extensor compartment) 1. It is distinct from intersection syndrome which oc...
Dysplasia epiphysealis hemimelica (DEH), also known as Trevor disease, is an extremely rare, non-hereditary disease that is characterised by osteochondromas arising from the epiphyses.
The incidence is estimated at ~1:1,000,000 3. There is a recognised male predilection (M:F = 3:1...
Ehlers-Danlos syndrome comprises a heterogeneous group of collagen disorders (hereditary connective tissue disease).
There is a recognised male predominance.
Clinically manifests by skin hyperelasticity and fragility, joint hypermobility and blood vessel fr...
Elbow synovial fold syndrome refers to a condition where patients experience a cluster of symptoms due to the presence of synovial folds (also known as synovial fringe or plicae).
It tends to be more common in athletic young adults. It is associated with certain sporting activitie...
Failed back syndrome refers to persistent leg and/or lumbar back pain after a surgical procedure. The pathophysiology of this syndrome is complex, as often the operation was technically successful.
Other names for failed back syndrome include failed back surgery syndrome, post-lam...
Familial multiple lipomatosis (FML) is a hereditary syndrome of multiple encapsulated lipomas which are found on the trunk and extremities, with relative sparing of the head and shoulders.
It is clinically distinct from the similarly named multiple symmetric lipomatosis with which...
Fatco syndrome is a syndrome consisting of
tibial campomelia and
It is a syndrome of unknown genetic basis and inheritance with variable expressivity and penetrance.
Fuhrmann syndrome and Al-Awadi syndrome are said to be similar to FA...
In fat-pad impingement syndromes, the aetiologies are different for each knee fat pad.
In anterior suprapatellar fat pad impingement syndrome, the cause is usually due to either a developmental cause related to the anatomy of the extensor mechanism or may be related to abnormal mechanics. In th...
Felty syndrome is a rare haematological syndrome in rheumatoid arthritis.
It is thought to occur in ~ 1% of patients with rheumatoid arthritis 2.
Felty syndrome comprises of the triad of:
typically with severe articular and extra-art...
Femoral facial syndrome, also known as femoral hypoplasia-unusual facies syndrome, is a rare congenital syndrome characterised by varying degrees of femoral hypoplasia and facial dysmorphism 1.
Femoral facial syndrome can cause varying degrees of femoral malformation rang...
Flat back syndrome (FBS) refers to the decrease or absence of the normal lumbar lordosis resulting primarily in chronic lumbar pain.
Flat back syndrome is a different condition from straight back syndrome and the two should not be confused or conflated.
Focal dermal hypoplasia syndrome, is also known as Goltz syndrome, and is not to be confused with the similar-sounding Gorlin-Goltz syndrome.
A rare disorder that follows an X-linked dominant inheritance pattern. More commonly seen in males than females. Worldwide only 200-300 cas...
Glycogen storage disease (GSD) refers to a number of syndromes which are characterised by a defect in synthesis, metabolism or storage of glycogen.
There are many types of GSD:
type I: von Gierke disease
type II: Pompe disease
type III: Cori or Forbes disease
type IV: Andersen di...
Goodman syndrome is a type of acrocephalopolysyndactyly (often considered type IV). It is an extremely rare genetic disorder characterised by marked malformations of the head and face, abnormalities of the hands and feet, and congenital heart disease. The syndrome is inherited as an autosomal re...
Grisel syndrome is a rare cause of torticollis that involves subluxation of atlanto-axial joint from inflammatory ligamentous laxity following an infectious process in the head and neck, usually a retropharyngeal abscess.
It usually occurs in infants or young children.
Haglund syndrome refers to the triad (Haglund triad) of:
insertional Achilles tendinopathy
Haglund deformity (i.e. posterosuperior calcaneal exostosis)
This results in pain at the back of the heel. It is associated with calcaneal spurs, and the wearing of high heels (...
Hajdu-Cheney syndrome is a very rare connective tissue disorder with only 50 cases reported in the literature 7.
It is mostly diagnosed in adulthood or adolescence with the presence of a positive family history. There has been no link between severity of disease and age o...
Hamatolunate impingement is an uncommon cause of ulnar-sided wrist pain. The condition occurs most commonly in wrists where there is type II lunate morphology (existence of a medial facet on the distal lunate for articulation with the hamate). Repeated impaction of the opposing articular surface...
Hand-foot syndrome, also known as palmar-plantar erythrodysaesthesia or Burgdorf reaction, is a benign, aseptic, self-limiting complication of many chemotherapeutic agents characterised by a widespread erythema, oedema and ulceration of the hands and feet.
Hemihyperplasia, also known as hemihypertrophy, is asymmetry in size between the right and left of the body, more than can be attributed to normal variation.
Hemihyperplasia is more scientifically correct than hemihypertrophy as the cells are hyperplastic rather than hypertrophied ...
Hereditary angiopathy with nephropathy, aneurysms, and muscle cramps (HANAC) syndrome is an autosomal dominant monogenic COL4A1-related disorder.
The exact prevalence is unknown.
The cardinal features of HANAC syndrome are helpfully described in the name of...
Hereditary multiple exostoses, also known as diaphyseal aclasis or osteochondromatosis is an autosomal dominant condition, characterised by the development of multiple osteochondromas.
Hereditary multiple exostoses demonstrate an autosomal dominant inheritance pattern, with incomp...
Hunter syndrome, also known as mucopolysaccharidosis type II (MPS II) is a rare genetic mucopolysaccharidosis disorder characterised by specific clinical features 1.
Hunter syndrome is an X-linked recessive disease and therefore much more common in males. It is a rare disorder wit...
Hurler syndrome is one of the mucopolysaccharidoses (MPS type I).
The estimated incidence is ~1:100,000.
It manifests in the first years of life with intellectual disability, corneal clouding, deafness, and cardiac disease. Death usually occurs within the f...
Iliotibial band (friction) syndrome is a common cause of lateral knee pain related to intense physical activity resulting in chronic inflammation.
Commonly affect young patients who are physically active, most often long distance runners or cyclists. The exact prevalence is unknow...
Ischiofemoral impingement refers to the impingement of soft tissues between the ischial tuberosity and lesser trochanter of the femur, primarily the quadratus femoris muscle manifesting with muscle belly oedema. Narrowing of the distance between these two osseous landmarks (ischiofemoral space a...
Ischiopubic synchondrosis asymmetry (also known as van Neck-Odelberg disease) is characteristic enlargement of one of the ischiopubic synchondroses. It is largely considered an anatomic variant of skeletal developmental, given that it is a common and usually asymptomatic finding.
However, some ...
Jaffe-Campanacci syndrome is characterised by:
multiple non-ossifying fibromas of the long bones and jaw
café au lait spots
hypogonadism or cryptorchidism
giant cell granuloma of the jaw
The Jarcho-Levin syndrome (JLS) or spondylothoracic dysostosis is a rare autosomal recessive heterogeneous disorder that can occur with variable severity. Previously the condition spondylocostal dysostosis was also considered as part of the JLS spectrum but is now considered a distinct pathologi...
Kasabach-Merritt syndrome, also known as haemangioma thrombocytopenia syndrome, is a rare life-threatening disease found in infants in which a rapidly growing vascular tumour is responsible for thrombocytopenia, microangiopathic haemolytic anaemia and consumptive coagulopathy.
Klippel-Feil syndrome is a complex heterogeneous entity that results in cervical vertebral fusion. Two or more non-segmented cervical vertebrae are usually sufficient for diagnosis.
There is a recognised female predilection 1. Klippel-Feil syndrome has an incidence of 1:40,000-42,...
Klippel-Trénaunay-Weber syndrome (KTWS) is a syndrome combination of capillary malformations, soft-tissue or bone hypertrophy, and varicose veins or venous malformations. It is considered an angio-osteo-hypertrophic syndrome.
KTS classically comprises a triad of:
port wine naevi
bony or soft ...
Kyphomelic dysplasias (also known as "pseudocampomelia") is thought to be a heterogeneous class of "bent bone" skeletal dysplasias. Entities included in a differential for the class are:
congenital bowing of the long bones
cartilage-hair hypoplasia (CHH; metaphyseal dysplasia, McKusick type)
Lambert-Eaton myasthenic syndrome (LEMS) is a rare neuromuscular junction disorder of paraneoplastic or primary autoimmune aetiology.
LEMS is the second most common neuromuscular junction disease after myasthenia gravis.
Two-thirds of LEMS present as a paraneoplastic syndrome se...
Langer-Giedion syndrome, also known as trichorhinophalangeal syndrome type II, is an extremely rare autosomal dominant genetic disorder.
The effects are seen mainly on the skeletal system and primarily involves
digits of the hands and feet: phalangeal
Larsen syndrome (LS) is an extremely rare disorder, often classified as a type of osteochondrodysplasia.
The estimated incidence is thought to be at ~ 1 in 100,000 people. There may be an increased female predilection.
It is characterised by many features i...
Laurin-Sandrow syndrome is a rare disorder characterised by tetrameric polysyndactlyly.
polysyndactyly of the hands (both post-axial and pre-axial)
mirror polysyndactyly of the feet
absence of the radius and tibia
Leprosy, previously known as Hansen's disease, is a chronic infectious disease caused by Mycobacterium leprae and presents mainly in tropical developing countries.
It is most common in tropical developing countries and is endemic in over 100 countries. Worldwide, there is a preval...
Levator ani syndrome (LAS) is a musculoskeletal pain syndrome involving the pelvic floor, thought to be caused by spasm or scarring of the levator ani muscles.
Levator ani syndrome is characterised by recurrent pain, pressure or discomfort in the region of the rectum, sac...
Löfgren syndrome is a specific acute clinical presentation of systemic sarcoidosis that usually manifests with lymphadenopathy, fevers, erythema nodosum, and polyarticular arthritis.
It is important to not confuse this syndrome with Löffler syndrome, as the names are quite similar...
Madelung disease, also known as Madelung-Launois-Bensaude syndrome or neck lipomatosis or multiple symmetric lipomatosis, is a rare benign entity clinically characterised by the presence of multiple and symmetric, non-encapsulated masses of fatty tissue, usually involving the neck and the upper ...
Maffucci syndrome is a congenital nonhereditary mesodermal dysplasia characterised by multiple enchondromas with soft-tissue venous malformations (haemangiomas).
On imaging, it is usually portrayed by a short limb with metaphyseal distortions due to multiple enchondromas, which may appear grote...
Mainzer-Saldino syndrome (also known as conorenal syndrome (CRS)) is a rare condition and is one of the ciliopathies. It is due to mutations in the IFT140 gene, whose protein product is one of the six parts of the intraflagellar transport complex A.
The syndrome's key characteristics are:
Marfan syndrome is a multisystem connective tissue disease caused by a defect in the protein fibrillin 1, encoded for by the FBN1 gene. Cardiovascular involvement with aortic root dilatation and dissection is the most feared complication of the disease.
The estimated prevalence is...
Mazabraud syndrome is a rare syndrome characterised by skeletal fibrous dysplasia and intramuscular myxomas 1-3.
Only 107 cases have been reported in the global literature (as of 2019) 1,3-5,15. The prevalence is ~ 1 in 1,000,000 3 with a strong female predilection (68-84%) 1,3. T...
McCune-Albright syndrome (MAS) (also known as McCune-Albright-Sternberg syndrome) is a genetic disorder characterised by the association of:
endocrinopathy: precocious puberty
polyostotic fibrous dysplasia: more severe than in sporadic cases
cutaneous pigmentation: coast of Maine 'cafe au lai...
Medial patellar plica syndrome is one of the conditions that can be associated with the presence of synovial plicae of the knee (in this instance a medial plica). It can be a common source of anterior knee pain.
While it can affect those of any age, it typically involves the young...
Medial tibial stress syndrome (MTSS), also known as shin splints, describes a spectrum of stress injury that occurs at the medial tibia. This term is often used to indicate any type of tibial stress injury or the earlier manifestations of a tibial stress lesion before a fracture component can be...
Menkes disease, also known as trichopoliodystrophy or kinky hair kinky vessel syndrome, is an X-linked recessive disorder that results in a derangement in copper handling. It results in low copper levels and subsequently, deficiency in copper-dependant mitochondrial enzymes.
Metaphyseal chondrodysplasia (also known as metaphyseal dysplasia or dysostosis) is a type of skeletal dysplasia.
Schmid type - mild type, due to mutation in type X collagen (COL10A1 gene), metaphyses are cupped resembling rickets
Pena and Vaandrager type - intermedi...
Milwaukee shoulder refers to a destructive shoulder arthropathy due to deposition of hydroxyapatite crystals, and identification of these crystals in synovial fluid is the cornerstone of diagnosis.
Milwaukee shoulder frequently affects older women, often with a history of trauma t...
Morgagni-Stewart-Morel syndrome consists of the triad of:
hyperostosis frontalis interna
excessive hair growth (virilism/hirsutism)
and is also associated with neuropsychiatric conditions. The cause is unclear.
History and etymology
It was first described in 1765 by the Italian ...
Morquio syndrome (in older literature it is sometimes called Morquio-Brailsford syndrome) is an autosomal recessive mucopolysaccharidosis (MPS) type IV.
Incidence estimated at ~1:40,000.
Many cases present at ~2 years of age and have normal intelligence. Cl...
Mucopolysaccharidoses (MPS) constitute a group of hereditary disorders, one of a number of lysosomal storage disorders, having in common an excessive accumulation of mucopolysaccharides secondary to deficiencies in specific enzymes (lysosomal hydrolases) responsible for degradation of mucopolysa...