Ollier’s disease is a rare, nonhereditary skeletal disorder characterized by a multifocal intramedullary proliferation of hypercellular dysplastic cartilage. It is a type of enchondromatosis.
Maffucci’s syndrome is another type of enchondromatosis where the skeletal lesions are accompanied by hemangiomas of skin, soft tissu, and viscera.
Enchondromatosis represents a distinct developmental disorder of enchondral ossification and is more likely to be cartilage dysplasia. Enchondromatosis is not multifocal enchondromas of bone.
Enchondromatosis is a sporadic congenital disorder that, unlike multiple exostoses, shows no hereditary features.
Ollier disease was described by Louis Léopold Ollier in 1900. It is also known by names of dyschondroplasia and multiple enchondromas.
In Ollier’s disease, the lesions have a tendency to be metaphyseal and are sometimes eccentrically placed, with predominant unilateral involvement of the appendicular skeleton. The clinical manifestations typically appear during childhood, and the extent of skeletal involvement is variable.
It is identifiable by distinct radiographic and microscopic features and peculiar skeletal distribution which also differentiates it from the common conventional enchondromas.
Ollier’s disease is rare, and its true incidence is unknown. There is no clear sex difference in incidence.
The extent of involvement of the skeleton varies widely from limited involvement of one or few bones to multiple bones involvement and severe deformities.
The disease has a tendency to predominate on one side of the body through bilateral involvement is seen.
There is a predilection for the appendicular skeleton. In severe forms, the trunk bones can also get involved.
The bone most often affected are
- Hand
- Tubular bones of foot
- Femur [most common long bone affected]
- Tibia
- Humerus
- Forearm
Among the trunk bone, pelvic bones are most commonly affected. The lesions are also seen in the scapula and ribs.
Skull bones, facial bones, and vertebrae are not affected.
Bilateral occurrence needs not to be symmetrical necessarily.
There is an increased risk of chondrosarcoma in the lesions occurring later in life [ The risk is up to 25-30% at 40 years].
Pathophysiology
The lesions are essentially hamartomatous proliferations of cartilage cells within the metaphyses or perversion of enchondral growth and are therefore confined to cylindrical bone.
In mild cases, the lesions may be confined to one hand and there is a strong tendency to a unilateral distribution of the lesions. Lesions affecting the more proximal bones are more extensive and vigorous in growth and the region of the knee-joint and the lower end of the radius and ulna are particularly common sites.
When a single limb is affected, severe shortening may develop with associated deformities such as genu varum or valgum.
In the hand enchondromata in the phalanges and metacarpal bones are very common and their increase in size may cause considerable loss of hand function.
Pathology
Enchondromatosis has been associated with mutations during early fetal development.
PTHrP (parathyroid hormone-related protein) receptor gene has been implicated in cases of enchondromatosis in patients with a family history of mild skeletal dysplasia.
The growth of enchondromas stop after individual stops growing.
Occasionally patients will also be afflicted with multiple osteochondromas, a condition called metachondromatosis.
The affected bone, on cut section, shows extensive involvement and contain longitudinal extensions composed of irregular masses of cartilage that range in length from 1 to several centimeters, located in the metaphyseal parts of the long and extending into the diaphysis.
Presence of eccentric subperiosateal hyaline cartilage nodules can also be seen.
Microscopy is similar to enchondroma demonstrating a lobular arrangement of the neoplastic cartilage. The lesions in Ollier’s disease are more cellular and less calcified.
When nuclear cells atypia and immaturity of the extracellular matrix is visible, the lesion is hard to differentiate from chondrosarcoma grade 1.
Clinical Presentation
The condition is already present at birth when it may occasionally be noticed because of the shortness of an affected limb.
The individual typically presents in childhood. More diffuse and severe skeletal involvement, the earlier in life symptoms appear.
Slowly increasing swelling of the fingers is the most common presentation. If the long tubular bones are involved the child can present with angular deformity. Limb leg length discrepancy can occur as the affected bones grow more slowly. The findings are more evident in lower limbs.
Rarely, a pathologic fracture may be a presenting symptom, but more often occurs, later in the course of the disease.
A deformity in one of the paired bones, for example, radius, would also give rise to deformity in the other unaffected/ less affected bone as it tries to compensate.
Adults with severe enchondromatosis may have short and bowed limbs.
Compensatory changes in the spine such as scoliosis may be present.
The increasing size of multiple enchondromata in hands interferes with movements of the fingers so that eventually the hand may become almost useless.
Differential Diagnoses
- Maffucci syndrome
- Metachondromatosis
- Sarcoidosis
Imaging
X-rays
The lesions are often metaphyseal and diaphyseal, eccentric, and multifocal.
In the small bones of the hand, the lesions are globular and expand the bone so that the cortex becomes extremely thin and even perforates with an external projection of the cartilaginous mass. Spotty calcification is often present in the enchondromatous lesions.
In the long bones, the lesions involve the metaphyses and extend into the diaphysis as elongated, translucent columns giving rise to a striated appearance which is pathognomonic.
The radiologic appearance is sometimes referred to as fluted-column sign.
The metaphyseal region is expanded but relatively undistorted in shape and the shaft is short and often thick and dense.
Sometimes a lesion projects towards the surface of the bone but such projections point towards the epiphysial line in contrast to those in osteochondromatosis which are always inclined towards the center of the shaft.
The epiphyses are at first normal but in older children, they may show irregularity and mottling.
Treatment
There is no specific treatment available, and affected patients require surveillance for their lifetime because of the possibility of secondary sarcomatous change.
Mild lesions may not require any active treatment and should be kept under observation. Where required the treatment would be surgical.
For small bones like that of hand, chondromatas in affected phalanges and metacarpals can be curretted out and projections removed. If necessary, the cavities can be filled with autogenous or stored cancellous bone or cortical bone graft.
The multiplicity of lesions makes it impossible to tackle all of the affected regions in a severely involved hand and selection for operative treatment should be made of those bones that are interfering with joint movement.
In hand, sometimes a complete ray of the hand may need to be removed.
In other sites, removal may be needed at intervals because of discomfort, difficulty in dressing etc.
In most cases, the progression stops at puberty, but occasionally are known to grow even during adulthood.
In the lower limbs, a significant problem is leg length inequality. If the limb inequality at the end of growth is likely to be less than 10 centimeters (4 inches), leg-lengthening may be appropriate but if the shortening is very severe, amputation may be the only solution.
Osteotomy may be required to correct deformity and the fragments unite readily.
A watch needs to be maintained in adolescence and adult life for evidence of sarcomatous degeneration. Rapid enlargement of a tumor, particularly in a bone close to the vertebral axis, pain, or radiological suspicion of malignant change is an indication for biopsy.
