For a description of the general principles of the examination of the locomotor system we would like to refer to the section entitled: “The Examination of the Lower Extremities” from the Skills in Medicine program. Only the principles that are specific to the examination of the spine are discussed here.
The physical-diagnostic examination of the spine should be tailored to detect the most common disorders that can present themselves in or around the spine. Generally speaking, the pathologies of the spine can be subdivided into the following categories:
- posture and static abnormalities (e.g. idiopathic scoliosis, muscular imbalance)
- stress injuries (including lumbago, non-specific myalgia)
- degenerative disorders (including spondylarthritis, hernia nuclei pulposi, myelopathies)
- inflammatory processes (including sacro-iliitis, spondylitis, spondylodiscitis)
- malignant processes (including spinal metastases)
- congenital or acquired spinal abnormalities (including spondylosis, spondylolisthesis, congenital scoliosis)
- trauma (spinal fractures, whiplash lesion)
First and foremost, the physical examination involves a very extensive inspection, as posture or static abnormalities can form the basis of back problems. This inspection involves an assessment of both shape and posture aspects from crown to heel, starting ventrally, then dorsally and finally laterally on both sides. The active range of motion examination then follows, during which, if needed, the movements can be guided by the examiner using both their hands.
The passive range of motion examination of the spine is not a standard procedure, for the following reasons: Firstly, there is a risk of causing damage when (incompetently) conducting a passive range of motion examination of the spine. Secondly, too little additional information is obtained from the passive range of motion examination for the thoracic and lumbar spine.
The muscle tests are limited to observing tension of the abdominal and back muscles. However, if there is a reason to suspect a muscular imbalance at the pelvis level, then one can consider testing the various relevant muscles for strength and length (i.e. stretch). This part of the examination is described in “Special examination techniques”.
Palpation of bones, joints and soft tissue can take place in different postures and positions. Standing in upright position, the paravertebral musculature can have a different muscle tone than in prone position. With the spine in flexion posture (distance between the spinous processes increases) (for example, with the patient seated and/or lying sideways) and in prone position, the various spinous processes (particularly caudally from C7) can be palpated (and viewed) best. At the cervical level, the palpation of the spinous processes is made difficult during flexion by the tensing of superficial structures (e.g. nuchal ligament).
When suspecting cervical arthrogenic symptoms, palpation of the bony parts may help to differentiate between a disorder above C2 or below C2. If the cause lies above C2 then an X-ray examination is always indicated. The spinous processes of C2 are often easily palpable (this is the first bony mass that you encounter when going in caudal direction from the external occipital protuberance along the median line). Furthermore, it is important to palpate attachments of various muscles on the occipital bone when a myogenic cause for neck symptoms is suspected (from the external occipital protuberance via the superior nuchal line to the mastoid process on either side) (see Moore, Chapter 4).
The transverse processes in the cervical region are generally not palpable, with the exception of the atlantis transverse process (C1) since these protrude further.
It is not easy to distinguish all cervical spinous processes. Because of the nuchal ligament, a septum in the median line of the neck, and the muscle connected to it, the cervical spinous processes above C6 cannot be visualised. Localising C7 can occasionally be difficult because C6 and T1 are sometimes prominent. Usually, a distinction can be made if the patient carries out a flexion of the neck starting from the extension position: C6 quickly becomes less palpable, whereas C7 disappears later. The spinous process of C2 and the more caudally located spinous processes can, however, be palpated when the patient is seated, with the examiner supporting the forehead, or in sideways or supine position. This ensures that the cervical musculature and the nuchal ligaments are relaxed.
The cranial and caudal spinous processes of the thoracic spine are easily palpable, because these are pointed in the most dorsal direction. This is slightly more difficult for the more tilted spinous processes in the mid-thoracic region. The inferior angle of the scapula can be used as a reference point for the spinous process of T7. Palpation can be carried out in a caudal-cranial direction if necessary, because in this way one works against the longitudinal direction of the spinous processes and therefore they can be traced better. In the lumbar region the sizeable spinous processes can often already be visible when the patient is standing upright. Between the spinous processes, the strongly developed supraspinal ligaments can also be palpated. The highest point of the iliac crest can function as a reference point for disc L4/L5.
In the sacral region the superior posterior iliac spines are used for orientation purposes. When one palpates these spines from a caudal direction the palpating fingers are located at around level S2. A section of the joint groove of the sacro-iliac joint can only be palpated indirectly caudally from the superior posterior iliac spine because of the presence of ligaments and intrinsic back muscles.
Palpation of the pelvis, the iliac crest and various spines in particular, deserve special attention. The iliac crest is located between the superior anterior iliac spine and the superior posterior iliac spine. In humans with a normal posture, the superior anterior iliac spines are usually easily visible. In principle, they should be palpable in any person. The superior posterior iliac spines can often be localised during inspection by the presence of associated “holes” (= indentations). These indentations develop because, locally, the skin is directly connected to the bone via connective tissue fibres. However, it can also happen that the superior posterior iliac spines are observed as elevations. If the superior posterior iliac spines are not visible in any shape or form then the palpation can be more difficult due to the presence of a thick layer of subcutaneous adipose tissue. In order to use the spines as reference points for assessing the position of the pelvis, they can be approached from a cranial (from the iliac crest) or caudal direction.
The special tests should be conducted when indicated and can contribute to narrowing down the number of differential diagnoses and deciding upon the final diagnosis. Tests for proving sacro-ilitis are unfortunately not very sensitive or specific.
The usual measurements of muscle circumference in suspected atrophy cannot be carried out during an examination of the back in terms of measuring the circumference of the abdominal and back musculature.
The neurovascular examination does however have an important role to play, since back symptoms related to a hernia nuclei pulposi are often associated with neurological impairment; a spinal cord deformity can sometimes be the reason for (idiopathic) scoliosis. For an extended description of the neurological examination (e.g. in a patient with ischialigiform symptoms) we refer to the section “The Neurological Examination”.