What are the types &
effects of SCIs?
The effects of a spinal cord injury depend on a number of factors, for example the injury's severity and its location on the spinal cord. These effects are far-reaching, affecting not only those injured, but also friends and family. Read on to learn more.
Complete paraplegia is caused by complete damage across the spinal cord anywhere below the neck region, specifically to the following regions of the spine:
Thoracic (T1 to T12 bones, known as vertebrae) – the upper middle region.
Lumbar (L1 to L5) – the lower middle region.
Sacral (S1 to S5) – the lower region.
The main effects of this injury are the loss of movement and feeling in the legs (and usually the trunk of the body), whereas the arms and hands can still be used as normal.
Injury to the higher thoracic region (the T1 to the T6 vertebrae) causes a complete loss of function and sensation below the mid-chest. As a result, abdominal muscle is diminished meaning there is little trunk control and poor balance when sitting; the bladder and bowel functions will no longer work properly and function in the reproductive area is also lost.
Meanwhile, complete damage further down the spinal cord in the lower thoracic region (T9 to the T12) still means a loss of function and sensation in the legs, but abdominal muscle strength is preserved so there is good balance when sitting along with some general movement of the trunk.
The loss of function and sensation in the legs suffered by complete paraplegics can often be the catalyst for further secondary medical complications. Although not an exhaustive sample, some are listed below:
|Autonomic dysreflexia||Hyperthermia and hypothermia|
|Chronic nerve pain||Pneumonia|
|Deep vein thrombosis||Skin breakdown or pressure sores|
|Fertility in men may be affected||Spasticity|
Fortunately, through medical care and rehabilitation, there are methods to help minimise the chances of these complications. For example, to assist people with standing for short periods can help prevent pressure sores and Deep Vein Thrombosis (DVT).
A complete spinal cord injury resulting in complete paraplegia requires a stay in a specialist spinal hospital for approximately five months. During this time, extensive rehabilitation, skill building and physiotherapy is undertaken in order to prepare people with paraplegia for day-to-day life with their new physical challenges.
Upon leaving hospital care, complete paraplegics can usually remain fully independent with the ability to provide full self-care such as feeding, grooming, bathing, dressing and so forth. Most use a self-propelled (manual) wheelchair for mobility but some people who have suffered complete lower spinal injuries may be able to stand (with assistance) for short periods of time.
In fact, it's possible for some to be able to walk supervised for short distances, aided by such equipment as long leg braces and a weight-taking walker. If the spine’s site of damage is between the T6 and T12 vertebrae, the patient may even be able to use apparatus to walk independently, although it takes a great deal of strength and determination to do so.
Therefore, it is key to understand that complete paraplegia does not necessarily mean the complete loss of all leg function, and there are rehabilitation methods and equipment that can help people maintain their independence, and in some cases perhaps achieve what at first may seem like the impossible.
Complete tetraplegia is the most severe, and debilitating level of paralysis.
It is the loss of function and sensation in the arms, legs and body caused by complete damage to the spinal cord in the neck (cervical region).
The primary effects of complete tetraplegia vary depending on which part of the spinal cord has sustained injury.
The eight classifications of tetraplegia refer to the site of injury as the eight nerves protected by the seven vertebrae (bones) in the neck. From the top nerve (C1) to the bottom (C8), the higher the injury occurs then the greater the physical impact is on the rest of the body.
The table below provides a general picture of the extent of the effects. For example, it is clear that C1 tetraplegia has the largest amount of physical effects whereas C8 tetraplegia, whilst still extremely debilitating, generally has the least:
|Effects and/or Remaining Abilities||Types of Tetraplegia|
|Complete paralysis of the arms, body and legs||C1, C2, C3|
|Complete paralysis of the body and legs but with limited arm function||C4, C5, C6, C7, C8|
|Ability to move the head and neck|| Severely limited: C1, C2, C3 |
In some cases fully: C4
Fully, with good muscle strength: C5, C6, C7 & C8
|Ability to move shoulders|| Limited: C4 |
Good: C5, C6, C7 & C8
|Ability to bend elbows||C5, C6, C7 & C8|
|Ability to lift hands (wrist extension)||C6, C7 & C8|
|Cannot breathe unaided (machinery assistance required)|| C1, C2 |
In some cases: C3
|Ability to breathe without assistance|| In some cases: C4 |
C5, C6, C7 & C8
|Build-up of waste in windpipe. Assistance required for coughing|| C1, C2, C3, C4 & C5 |
In some cases: C6, C7 & C8
|Loss of bowel and bladder functionality||C1, C2, C3, C4, C5, C6, C7 & C8|
|Ability to bend and straighten elbows||C7 & C8|
|Partial finger movement, grip and mobility||C7 & C8|
|May transfer body independently depending on upper body strength||C7 & C8|
The near complete loss of function, sensation and mobility of complete tetraplegics can cause many secondary medical complications, some of which are listed below:
|Deep vein thrombosis||Pressure sores|
|Frozen joints||Respiratory infections|
These complications range from the mild to the life-threatening and although not all are guaranteed to occur, steps must be taken to minimise their chances, such as regularly moving the patient to prevent pressure sores or reacting quickly to Autonomic Dysreflexia to prevent strokes.
A high level of care and assistance is required after a complete spinal cord injury in the neck and usually, a six to eight month stay in a specialist spinal hospital is required for rest and rehabilitation.
Following discharge, there are constant technological advances that continue to improve the lives of those with complete tetraplegia: from breathing apparatus, powered wheelchairs and automatically opening doors, to equipment activated by mouth, chin, head, and even blink control. In some cases, reconstructive hand surgery may be possible to improve function, such as grip and release, or even the attachment of a bionic glove.
C1 to C4 tetraplegics will generally require the most personal care and assistance, but for those with some arm movement present - or enough to use assistive equipment - it could even be possible to perform daily activities to a high enough standard to live independently.
An incomplete spinal cord injury is when the cord becomes partially damaged.
It is the most common type of spinal injury and the one where either limited movement or feeling (or both) can remain below the point of damage.
The effects of an incomplete injury differ depending on several factors:
How the spinal cord was damaged.
The area of the spinal cord affected.
The strength of the injury-causing impact.
However, there are five general classifications of injury and this section discusses each in turn.
Anterior cord syndrome
This injury happens when an impact is strong enough to damage the artery that runs along the front of the spinal cord, perhaps by a fragment of broken bone or a slipped disc.
As well as a loss of strength beneath the point of injury, there is also a loss of feeling of temperature and pain.
Some sensations are preserved, however, such as the feeling of vibration and the awareness of positioning. For some people, it may be possible to recover some movement.
Central cord syndrome
This is an injury to the nerves at the centre of the spinal cord, usually the result of trauma, which prevents the brain sending information down the spinal cord to the rest of the body.
These nerves are critical in enabling normal use of the arms and hands, so the main effect of central cord syndrome is that all arm function is lost. Depending on the severity of the nerve damage, there may also be a loss of bladder and bowel control.
Some function can be preserved in the legs, and during the recovery process, it may be possible to improve this gradually.
Posterior cord syndrome
Posterior Cord Syndrome is an incomplete injury to the back of the spinal cord. The resulting effects are characterised by a continued ability to move but with a lack of limb control and coordination.
Below the site of injury, there will still be good muscle power and sensations of temperature and pain are usually preserved.
Brown-Sequard Syndrome is a rare condition where injury to one side of the spinal cord causes an inverted mirror image of complications.
Beneath the site of damage to the cord, the effects can be a complete loss of movement on one side of the body but with preserved sensations of pain and temperature. However, on the other side of the body the opposite is true in that sensations of pain and temperature are lost but normal movement is preserved.
Cauda equina syndrome
The cauda equina is a mass group of nerves in the lower back area. Once trauma is suffered the nerves are compressed, which at the very least causes strong lower back pain.
More extreme is the partial, or in some cases the complete loss of movement and feeling as well as bladder and bowel dysfunction.
However, if the nerves have not suffered too much trauma and damage, it is possible for them to regrow and encourage some recovery of movement.
Find out more about how spinal cord injuries are treated in our rehabilitation section.