Vertebral Compression Fracture

Vertebral compression fracture occurs when a part in the vertebra collapses due to the compression of the bone in the spine. With age, vertebrae is weakened and loses its strength and leads to a condition called osteoporosis. Osteoporosis is a kind of bone loss that causes bones to break easily. Osteoporosis is the leading cause of vertebral compression fractures especially in the age group of 40 to 50 and above. Post menopausal women and men above the age of 65 years are at highest risk of suffering from vertebral compression fractures.

Apart from osteoporosis, there could be other reasons that lead to vertebral compression fractures. Young adults suffer from vertebral fractures due to spinal injuries during rigorous exercises, sports activities or accidents. These compression fractures normally heal within 8 to 10 weeks with good rest and pain medication. Vertebral compression fractures may also be attributed to cancer tumors associated with multiple myeloma and metastatic bone disease. In very rare cases, infection or Osteomyelitis of the vertebra also results in compression fractures.

Wedge fractures are the most common type of compression fractures wherein the front part of the vertebral body collapses and becomes wedge shaped. Other types of vertebral compression fractures include biconcave (collapse of central portion of vertebral body) crush fractures (collapse of entire vertebral body). These fractures happen most commonly in the thoracic spine (the middle portion of the spine), and lumbar spine (low back).

Symptoms of Vertebral compression fracture

Compression fractures caused by injuries produce sudden onset of sharp and throbbing pain. Fractures caused by osteoporosis may cause very mild to severe pain in the back. Normally the pain is intense in standing posture and there is respite when lying down.

Vertebral compression fractures also lead to kyphosis and loss of height especially with the fractures associated with osteoporosis.

Sometimes a severely fractured bone can impinge on the spinal cord. Thus, numbness or tingling in limbs or other areas of the body may occur if the spinal cord is affected. This can impair sensation in the areas supplied by the damaged nerve tissue.

Diagnosis

Doctor's evaluation of symptoms plays a major role in diagnosing compression fractures. Noting of complete history of the patient and clinical examination are necessary to determine the presence of vertebral compression fracture. When doctor suspects vertebral compression fracture, an x ray is ordered to confirm the diagnosis. If the X-Ray reveals a fracture, further imaging tests like CT scan and MRI are performed to rule out the involvement of spinal cord and also to understand the age of the fracture. A neurological exam may also be done to test for reflexes, muscle strength and sensory perception.

Treating Vertebral Compression Fracture

The conventional methods of treating vertebral compression fractures include pain medication, rest and bracing. While pain medication helps in alleviating the pain to some extent, back braces reduce the chance of further collapse of the bone, prevent deformity, and allow injuries to heal by taking the pressure off the fractured vertebral bone. Giving rest to the back by decreasing activities as much as possible helps in healing the fractures naturally and quickly.

There are also some minimally invasive methods used to treat vertebral fractures which are gaining popularity. Vertebroplasty and Kyphoplasty are two medical procedures that are increasingly being used to treat compression fractures. Here the fracture is treated by injecting a bone cement onto the collapsed bone through hollow needle. These are image-guided surgical procedures with minimum invasion that promise faster pain relief.

Further treatment also depends upon the underlying cause that is leading to vertebral fracture. If the osteoporosis is causing the bones to collapse, doctor may prescribe calcium and other bone strengthening supplements to avoid future compression fractures. If a tumor has caused compression fracture, more invasive surgery will be required remove sections of bone or tissue.

Osteogenesis Imperfecta

Osteogenesis imperfecta or OI, also known as brittle bone disease, is a genetic disorder that is characterized by weak and fragile bones that break easily. Osteogenesis imperfecta is caused by a genetic defect that disables the body to make strong bones. A person may experience occasional fractures or may have multiple fractures throughout life depending upon the severity of Osteogenesis imperfecta present. Apart from fragile bones, people with OI suffer from teeth problems - Dentinogenesis Imperfecta, hearing loss, muscle weakness, loose joints (joint laxity) and skeletal malformations.

Causes of OI

Osteogenesis imperfecta is either inherited from a parent who has the defective gene or could be a result of new mutations. Due to the defective gene, an important protein substance called type I collagen is not produced in the body. This protein plays an important role in forming connective tissues in bones and also helps in forming ligaments, teeth and the white outer tissue of the eyeballs (sclera). Due to poor production of the protein, bones become brittle and fragile and tend to break easily. Most of the mutations in OI exist in the two type I collagen genes, COL1A1 and COL1A2 and account for almost all the forms of OI.

Classification of Osteogenesis imperfecta

Depending upon the severity of the Osteogenesis imperfecta, the condition is divided into type 1, type 2, type 3, type 4. These types are classified mostly by fracture frequency and by characteristic features. Recently, research has identified three more additional variations to Osteogenesis imperfecta known as type 5, 6 and 7.

Type 1

Type 1 Osteogenesis imperfecta is the mildest and the most common form of OI. More than 50% patients suffer from Type 1 Osteogenesis imperfecta. In this type, though body produces normal type I collagen but only half the normal quantity. People with Type 1 OI may experience fewer fractures, and most often the condition may go unnoticed for several years after their birth.

Type 2

Type 2 Is the most severe form of Osteogenesis imperfecta often resulting in bone deformities in the child. Type 2 OI normally turns out to be fatal with the production of very little or poor quality collagen being produced in the body. Infants with type 2 OI are born with fragile rib cage and underdeveloped lungs. They usually die either in the womb or soon after birth.

Type 3

Osteogenesis imperfecta type III is severely progressive type associated with symptoms like short stature, a triangular face, severe scoliosis, grayish sclera, and Dentinogenesis imperfecta (impaired and irregular teeth with yellow-blue tinge). Infants with type 3 OI have fractures at the time of birth itself, and few infants reveal a fractured and eventually healed bones in the womb itself.

Type 4

Type 4 Osteogenesis imperfecta can range from very mild to severe form often resulting in growth retardation in children. A child with type 4 OI is short with bow shaped legs. Symptoms like tinted sclerae (white of the eye) and dental deformities may also be present at the time of the birth. Child normally suffers from Long bone fractures, vertebral compression, scoliosis, and ligament laxity with type 4 OI.

Type 4 also has two sub types called type 5 and type 6 OI. Though clinically they resemble type 4, types 5 and 6 have unique patterns to the bones. Type 5 exhibits features like ossification of interosseous membrane of the forearm with radial head dislocation, large callus formation and an abnormal histopathological pattern. Type 6 will have elevated alkaline phosphatase and blue-white sclerae.

Diagnosis

Most severe forms are diagnosed before birth itself. Ultrasound scanning during second trimester may reveal deformity of limbs, abnormally short fetus, irregular skull shape, lack of mineralizations and narrow chest cavity. Few cases are diagnosed soon after the birth and mild type of OI is found out much later in life when such individuals suffer from repeated fractures. However, the following diagnostic methods are used to assess the condition.

• Clinical examination, wherein history of frequent fractures with minimal trauma is noted
  
  
• X-Ray
  
  
• Genetic testing of a blood sample (DNA )
  
  
• Skin biopsy to assess collagen production.

Treatment

Since Osteogenesis imperfecta is a genetic condition, it does not have a cure. Patient will be treated symptomatically and will be aided with external tools to provide maximum possible mobility. Efforts are also taken to improve muscle strength and boost the bone mass in the patient through physical therapy. Professionally designed exercise programmes are highly beneficial and play an important role in treating the patients suffering from OI. Patient may also be prescribed required nutritional supplements like calcium, and vitamin D along with physical therapy. Few suitable candidates are also treated with surgical procedure called intramedullary rod surgery wherein metal rods are inserted through the length of the long bones to support and strengthen them.

Of late, Bisphosphonates drugs are being used in treating Osteogenesis imperfecta. Bisphosphonates are used to decrease the amount of bone resorption. It also helps in preventing fractures and improve person's functional mobility. There is also research being done to understand the role of gene therapy in treating Osteogenesis imperfecta.

Prognosis

Prognosis of Osteogenesis imperfecta depends upon the severity of the conditions. Despite bone deformity, restricted activity, and short stature, often patients with OI lead productive and near to normal lives.

Terminologies :

• Osteogenesis : Growing new bone
  
• Osteocytes : Bone cells
  
• Osteoblasts : Bone cells building new bone structure
  
• Osteoclasts : Bone cells which scavange bone tissue
  

Vertebroplasty

Vertebroplasty is a medical procedure that is employed to treat compression fractures in the vertebrae. The procedure involves injecting medical grade bone cement into the vertebral bones that have been damaged or collapsed. This procedure offers support. Osteoporosis is the most common cause for fractured spine bones. Spinal tumors, traumatic injuries and rarely Hemangioma are some of the other causes for vertebral compression fractures (VCF) of the spine. However osteoporosis-led vertebral fracture is the most common clinical situation in which vertebroplasty is used. These fractures cause severe pain and reduce the mobility of the patient. Vertebroplasty is a recently developed image-guided surgical procedure with minimum invasion that promises faster pain relief. Vertebroplasty becomes the best alternative choice when conservative pain management does not provide relief to the patient. It is a simple day-care procedure that not only helps in stabilizing the broken bone but also prevents further compression of the affected vertebral area.

Vertebroplasty Procedure

An MRI scan is performed on the patient prior to the procedure to confirm the fracture. If MRI scan is not recommended for the patient due to any specific medical condition, CT scan is carried out to assess the exact location of the fracture. If the patient is on any kind of medication, it should be informed to the doctor. Anticoagulation medicines or blood thinners have to be stopped at least five days before the surgery. Vertebroplasty is performed under local anesthesia with sedation by an Interventional radiologist or neuroradiologist. He should be well trained in fluoroscopically guided needle placement and should be able to deliver the cement to the exact position skillfully.

The patient is made to lie face down during the procedure. A small hollow point needle is positioned into the crushed bone. The doctor navigates the needle into position using a . Once the needle is in position, bone cement is directly injected into the collapsed bone to secure it. It is a special cement called polymethylmethacrylate (PMMA) that hardens within 10 to 20 minutes and restores the strength and shape of the vertebrae alleviating the pain caused due to compression. Though PMMA cement is the most widely used ingredient to repair vertebral fractures, other new substances such as cortoss (an injectable, non-resorbable, polymer composite that is designed to mimic cortical bone) are being explored in place of PMMA cement as excess polymethylmethacrylate cement can become toxic in the body. More than one fracture can be fixed at the same sitting. Vertebroplasty reduces the pain instantly and helps the patient to return to normal activity in a short period of time. Few hours of rest is recommended soon after the procedure; however the patient can be discharged the same day.

Vertebroplasty is generally a safe procedure. But in rare cases, the cement may leak into adjacent areas leading to complications. If the leaked cement enters the vein and travels to the lungs, it will cause serious pulmonary problems. In worst cases, cement leak may press upon the spinal cord or compress nerves leading to nerve damage. It may also require further surgery to treat the condition. Possibility of infection, allergy and bleeding are some of the other risks associated with Vertebroplasty. Vertebroplasty is not a recommended treatment for herniated disks or arthritis related back pain.

Tags: #Vertebral Compression Fracture #Osteogenesis Imperfecta #Vertebroplasty