Due to the lack of proper lifestyle and adequate exercise nowadays, the prevalence of back pain has significantly increased. So let's understand the primary understanding about what back bone is, what is its function, and what kind of pathologies can result from it.
The spine or vertebral column is a column composed of stacked bones called vertebrae. The average length of the vertebral column is 72 cm in male and 62 to 72 cm in female. Each vertebra has a fibrocartilaginous disc (disc) below it and are connected by special types of fibers (strong ligaments) and nerves that strengthen the spine. There are a total of 33 vertebrae in our backbone:
The following figure shows the natural curves of the spine :
Each vertebra has a transverse process and a spinous process plus an articular surface for articulation with the upper and lower vertebra. This joint is called facet joint. Transverse process and spinous process help in the attachment of various types of muscles and ligaments.
The cavity in the centre of all the vertebrae forms a continuous canal from top to bottom called the spinal canal. Spinal cord along with its three coverings (dura mater, arachnoid mater, pia mater) passes through this canal. A nerve emerges from spinal cord on both sides at the level of each vertebra which carries various types of sensations (cold, heat, movement, pain etc.) to the associated organs at each level. Spinal cord is surrounded by fluid called cerebro spinal fluid-CSF which provides nutrition to the nerves.
Adjacent to the disc are cartilaginous endplates, which further enhance its structural integrity and function. These fibrocartilaginous plates serve to distribute forces evenly across the spinal column, mitigating impact and minimizing wear and tear on the vertebrae. The structure depicted in the accompanying illustration represents the intervertebral disc, crucial for spinal support and flexibility. Positioned between adjacent vertebrae, it comprises a central nucleus pulposus surrounded by annulus fibrosus.
The disc which acts as a cushion between two vertebras is shown in the next figure. The disc is composed of nucleus pulposus fibres in the middle and annulus fibrosus in the periphery. Above and below the disc are cartilaginous plates. This fibrocartilaginous plate serves to absorb the shocks that the vertebrae encounter during various daily activities. The vertebral column ends at the level of the lumbar spine (L1). Below this level the spinal nerves of the waist as well as the sacrum run distinctly with their covering (sheath).
Let us understand back/spinal pain. The common causes of back pain are as follows :
Due to accidents (falling from heights, road accidents) sometimes the transverse process of the vertebrae fractures, causing disturbance to the normal balancing mechanism of the associated muscles and nerves causing back pain. Due to pressure of the vertebral body on the main nerve, there may be paralysis below the level of the fracture. In such cases, it may be necessary to operate immediately or urgently. Timely fixation of the spine is necessary to prevent major nerve damage.
Back pain can also be caused by an infection in the vertebrae or disc. The most common causes of infections are bacteria (pyogenic, tuberculous etc.), parasites, syphilis, etc.
Due to infection, pus collection inside causes pressure on nerve, disc, or other structures. Usually, the two adjacent vertebrae and their connecting disc are infected. Sometimes the abscess spreads to the surrounding muscle and appears as a paraspinal abscess under the skin.
Over time, infection can spread causing Gibbus-Kyphus deformity in which the spine bends from that level pressing on the spine causing problems. Often the pus enters the spinal canal (epidural abscess) causing pressure on the spinal cord which can cause pain and paralysis. In such cases, pus examination (needle biopsy or open biopsy) depending on the type of organism, long-term medication, and rest relieves the problem. If the pressure on the spinal cord is high or sensation in the adjacent limbs is low or if the muscles are found to be weak (motor weakness/paralysis), then it becomes necessary to operate.
Calcium deficiency leads to the weakening of the bones, which is called osteoporosis. Such bones can fracture due to minor injuries during daily activities and cause back pain. Generally, osteoporosis is more common after menopause.
Other reasons of osteoporosis include :
Spondylolisthesis refers to a condition where one vertebra slips forward over another vertebra, commonly occurring in the lower back.
There are two main mechanisms for this :
The vertebrae at the lower back are connected to the sacrum and coccyx bones. This connection, known as the Sacroiliac Joint (SI Joint), experiences increased relaxation of various muscles during pregnancy widening the birth canal. During pregnancy, childbirth, and postpartum, the relaxed muscles and ligaments around the SI joint undergo increased stress and strain, leading to discomfort in the lower back. This discomfort is often relieved by rest and medication. Gentle exercises (under proper guidance) and rest help gradually restore the muscles to their pre-pregnancy state. If discomfort persists after childbirth and is not relieved by medication intra-articular steroids provide relief.
During adulthood, around the age of 45-50 years, ossification occurs in the capsule anterior to the SI joint, leading to lower back pain. The stretching of ligaments due to falls from heights or pelvic ring fractures during accidents can cause strain on the nerves, resulting in lower back discomfort.
Infections such as tuberculous or pyogenic spondylitis, intestinal arthropathy, Reiter's disease, and other conditions can cause inflammation in the SI joint, leading to discomfort.
Lower back pain can be associated with conditions such as ankylosing spondylitis, intestinal arthropathy, and Reiter's disease, among others, causing inflammation in the SI joint.
Due to traveling, heavy lifting, injury, and aging, the various parts in the cushion gradually lose their properties. The cushion loses its shock absorbing capacity due to rupture of the cartilage plate, breakdown of annular fibers and reduction of the regeneration capacity of the nucleus. Due to rupture of the annular fibers, the intermediate nucleus (which has expansive properties) enters the canal and exerts pressure on the spinal cord and spinal nerves. As this pressure remains for a long time, the blood circulation of the spine gradually decreases. Degenerative changes (drying of veins) occur due to insufficient nutrition.
As a result, the patient complains of pain in the associated organ, tingling, claudication, motor weakness, numbness, inability to stand for a long time, etc. Symptoms that appear in the legs due to root compression of the nerves are called Sciatica.
Long-term pressure in the spinal cord and nerves leads to loss of bowel/bladder control (loss of bowel/bladder control).
Like Prolapsed Intervertebral Disc(PID), osteophytes (bony growth) and hypertrophy of ligamentum flavum can also cause narrowing of the spinal canal, reproducing above mentioned symptoms. This is known as spinal stenosis.
Usually, in case of bulging, the doctor advises X-ray after examining the patient.
The following information can be found in this X-ray :
X-rays can detect bone problems, but modern tests like MRI (magnetic resonance imaging) help diagnose problems in soft tissue structures like muscles, cartilage, spine, ligaments, etc.
The following problems can be detected in MRI :
It contains detailed information about the spinal canal. Special information can be obtained about the spinal canal, cord, and nerve root compression, the severity of compression, etc.
MRI cannot be done if a metal implant, artificial heart valve, or pacemaker, is placed in the body. In such cases, a CT scan or CT myelogram is advised.
Probable clinical diagnosis is confirmed after proper investigations like :
Conservative Treatment : Conservative management includes advice (painkiller drugs), muscle relaxants, physical therapy (rotation, traction), and heat therapy (local heat therapy, shortwave diathermy) which provide significant relief in the initial stages. It is essential to minimize activities that put strain on the spine, such as long journeys (on rough roads), lifting heavy weights, bending forward for extended periods, and prolonged sitting. Avoiding all these activities is necessary.
This conservative treatment is usually provided for a period of 3 to 6 weeks. If complete relief is not achieved after this treatment, X-rays, MRI scans, etc., may be advised to determine further management.
Injection Therapy : When conservative treatment fails to provide relief and MRI shows increased pressure on the nerve roots, epidural injections (steroids) can be given. These injections reduce swelling and provide pain relief. If necessary, another injection can be given after two to three weeks. These injections can be repeated two to three times for maximum benefit. However, in cases of pure mechanical compression, injections do not provide significant relief. In such cases, surgical advice (surgery) may be recommended according to the diagnosis.
Disc Prolapse (Slipped Disc) : For disc prolapse where the ruptured disc causes compression on the spinal nerves, surgical options include open discectomy, microdiscectomy, endoscopic microdiscectomy, or disc replacement surgery where the damaged disc is replaced with an artificial disc that functions like a normal disc. The decision for surgery is made after the failure of conservative management and the identification of the disc causing compression through diagnostic imaging like MRI.
Canal Stenosis : For lumbar canal stenosis, distraction laminoplasty is performed to create more space in the lumbar canal, relieving pressure on the spinal cord and nerve roots. For cervical canal stenosis, laminectomy or laminoplasty is performed to widen the canal.
Spondylolisthesis : Posterior lumbar interbody fusion (PLIF) involves removing the damaged disc between the vertebrae, inserting screws and rods to stabilize the spine (moss-Miami technique), and placing bone grafts between the vertebrae to promote fusion.
Anterior lumbar interbody fusion (ALIF) involves fusing the vertebrae from the front by removing the damaged disc and inserting bone grafts or cages in the disc space.
Fractures : For fractures in the lumbar spine, posterior decompression laminectomy followed by Moss-Miami fixation may be performed. For fractures in the cervical and dorsal spine, anterior corpectomy, Z-plate fixation, and cage/bone graft placement are performed.
Infections : Initially, conservative treatment is provided, including rest, wearing a brace, etc. If the patient does not improve within 4-6 weeks or develops neurological deficits or deformities, surgery may be necessary.
Surgical intervention for infections involves debridement (cleaning) of infected bone, cage/bone grafting, and fixation of the vertebrae.
These surgical procedures aim to stabilize the spine, decompress nerves, and address specific conditions or injuries to alleviate symptoms and restore function.
