Bone & joint diseases

Lecture no. 3

Prepared by Dr.Salah Mohammad FatihMBChB,DMRD,FIBMS(radiology)

There is poor mineralization of osteoid.

If occur before epiphyseal closure, it known as rickets.

If occur in adult ,it known as osteomalacia.

Rickets & osteomalacia

The changes are maximal where bone growth is occur, so they best seen in the knees, wrists & ankles

1. Loss of provisional zone of calcification.2. Indistinct metaphyses& metaphyses become irregular and

cupped.3. Wide growth plate.4. decreased bone density.5. Deformities of the bones occur because of bone softening.6. Greenstick fractures are common

Radiological finding of rickets

This patient shows abnormal bone density, with coarsened abnormal trabeculae in a generalized pattern. Even more prominently, we see widened and irregular metaphyses

Rickets

The anterior ends of the ribs are quite abnormal in this patient, with splaying at the costochondral junction (rachitic rosary)

Radiological findings;

1. Decreased bone density.

2. Looser’s zones; are short lucent band running through the cortex at the Rt angles & may have sclerotic margin, commonest site are scapula, medial aspect of femurs,& pubic rami & ribs

3. Bone deformity due to bone softening e.g. biconcave vertebra bodies

osteomalacia

This patient has generalized osteopenia. In addition, several of the right lower ribs demonstrate transverse fractures with a wide lucency at the fracture site (arrow). Your diagnosis?

Osteomalacia with looser’s zone

Cause mobilization of the calcium from the bone, resulting in a decreased bone density.

Hyperparathyroidism could be primary hyperparathyroidism (90 percent due to an adenoma) or secondary hyperparathyroidism due to renal dysfunction.

Hyperparathyroidism

Many patients with primary hyperparathyroidism present with renal stone & minority present with radiologically detected bone changes.

1. Generalized decrease in bone density.

2. The hallmark of hyperparathyroidism is subperiosteal bone Resorption.

3. Soft tissue calcification; vascular & chondrocalcification sometime occur.

4. Brown tumor are occasionally present which are small lytic lesion which could be single or multiple

Radiological features of hyperparathyroidism

Extensive subperiosteal resorption is seen on both the radial and ulnar side of the middle phalanges (white arrows, left hand). brown tumor in the left distal ulna as well as the left trapezoid (black arrows, left hand).a as well as in the right head of the third metacarpal and the base of the proximal phalanx of the fifth digit (black arrows, right hand).

Features of both primary & secondary hyperparathyroidism are similar except that brown tumors are much rarer & vascular calcification is commoner in secondary hyperparathyroidism

vascular calcification is the predominant finding

Hyperparathyroidism from renal osteodystrophy.

Generalized increase in bone density

Causes;1. Sclerotic metastases, commonest cause.

2. Osteopetrosis (marble bone disease); congenital, bone sclerotic & brittle leading to multiple fractures.

3. Myelosclerosis;there is replacement of the bone marrow by fibrous tissue & lay down of the bone which is usually appear as patchy areas of sclerosis

This child has extremely dense bones throughout the body. There is abnormal modeling at the metaphyses with flaring. Your diagnosis?

Osteopetrosis

Alteration in trabecular pattern & changes in the shape

1-Paget’s disease2-Hemolytic anemia

3-Radiation induced bone diseases

Usually is the chance finding in elderly. One or more bones may be affected, the

usual sites are pelvis, spine , skull & long bones

1-Paget’s disease

Cardinal features are ; thickening of the trabeculae & the cortex,

causing increase in bone density & loss of corticomedullary differentiation.

Enlargement of the affected bone.

Bone softening causes bowing & deformity of the bones & pathological fracture may occur

Radiological finding of Paget’s disaese;

this patient gives a classic appearance of advanced mixed lytic and sclerotic Paget's disease , bone expansion,loss of corticomedullary differentiation and anterior bowing of the tibia

Paget’s disease

typical picture-frame appearance of VB due to the enlargement and mixed lytic sclerotic pattern.

Paget's dsease

There are many types of hemolytic anemia , but radiological changes are seen in main two types; thalassaemia & sickle cell disease.

Both causes bone marrow hyperplasia, but sickle cell disease also may show evidence of bone infarction & infection

2-Hemolytic anemia

dense striations in a very widened diploic space of the cranium (hair-on-end appearance). Additionally, note that the paranasal sinuses are obliterated

Thalassemia

The metacarpals and phalanges are squared and show a very thinned endosteal cortex with abnormal density. Resorption of some trabeculae & remaining trabeculae become thick & prominent.

Thalassemia

Thinning of the cortex & bone expansion.

Resorption of some trabeculae & remaining trabeculae become thick & prominent.

In the skull; it cause widening of the deploe & perpendicular striation occur which is known as ‘ Hair-on-end’.

The ribs may enlarged & phalanges may become rectangular.

Radiological features of marrow hyperplasia

3-Radiation induced bone diseases

Mixed lytic and sclerotic density is seen involving most of the right upper ribs, the right clavicle, scapula, and proximal humerus. Multiple healed rib fractures are seen in this area.

Radiation osteonecrosis

Radiotherapy may cause local damage of the bone in the radiation field.

Early change may be limited to osteoporosis.

In severe case it may cause osteonecrosis; bone thinning & patchy increase in bone density with small lytic areas.

Pathological feature may occur

Occasionally radiation induce sarcomatous changes , usually osteosarcoma, which occur several years after the radiation therapy.

Changes in bone shapes

Is congenital disorder.

There are multiple bony projections known as osteochondromas or exostoses.

They have cartilaginous cup which may contain calcification.

When exostoses occur in the long bone , they occur near metaphyses & are directed away form the joint

Diaphyseal aclasia (multiple exostoses)

Osteochondroma (exostosis)

Diaphyseal aclasia (multiple exostoses)

Radiological features of joint diseases

Imaging technique Plain film remains important for imaging the

joint, but MRI is being increasingly used & specially useful for;

Meniscal & ligamentous tear in the knee. Rotator cuff tear of the shoulder. Avascular necrosis in the hip joint. Septic arthritis

MR Arthrography; involve injection of the contrast media in to the joint space & then performing an MRI scan.MR arthrography has role in the shoulder & wrist joints.

Plain film signs indicating presence of arthritis

1-Joint space narrowing; It occur in all forms of joint diseases

except avascular necrosis.

2-Soft tissue swelling; Periarticular soft tissue swelling is a feature

of inflammatory & infective arthritis. Discrete asymmetrical periarticular soft

tissue swelling can be seen in gout due to gouty tophi

3-Osteoporosis;

Occur in many type of painful conditions & under use of the bones is an important cause.

Diagnosis of arthritis

To Dx arthritis, it is important to have the following information;

1-Is more than one joint involved? RA, typically involve several joint

while infection & synovial tumors usually involve single joint.

2-Which joints are involved?

RA virtually involve the hand & feet, principally MCP, PIP, wrist joint &MTP.

Psoriatic arthritis usually affect the DIP.

Gout typically involve MTP of the big toe.

OA when seen in the hands ,it almost always involves DIP& often affect the CM joint of the thumb & in the large joints, it commonly involve hip& knee, but relatively rare in the ankle , shoulders & elbow joints unless there is some underlying causes.

Neuropathic arthritis ; Diabetic affect ankles & feet while syringomyelia affect shoulders, elbows & hands

3-Is a known disease present ? e.g hemophilia, DM

Degenerative arthritis (OA) Is the commonest form of arthritis. Changes occur secondary to wear &

tear of the articular cartilage.

Radiological features of OA

Inflammatory arthritis

Rheumatoid Arthritis

Radiological features of RA

OA•Joint space narrowed max. at wt bearing site•Erosion do no occur.

•Subchondral sclerosis may be seen.

•Sclerosis is a prominent feature.

•No osteoporosis.

•No peri articular soft tissue swelling

RA•Joint space narrowing uniform.

•Erosion is characteristic feature.

•Subchondral sclerosis is not a feature.

•Sclerosis not a feature unless there is secondary OA.

•Osteoporosis often present

•Peri articular soft tissue swelling

OA RA

Ankylosing spondylitis

Radiological features

Thank you