Thanks for asking your question. Although I am an internal medicine
physician, please see your primary care physician for specific
questions regarding any individual cases please do not use Google
Answers as a substitute for medical advice. I will be happy to answer
factual medical questions.
You asked the following:
"What could be the cause of muscle spasm, pins & needles, numbness and
weakness in the legs and constipation?"
Without seeing you, examining you or viewing the MRI results, I want
to stress that I cannot give you a diagnosis - please see your primary
care physician or neurologist. What I can do is present diseases that
contain that constellation of symtoms.
To find a unifying cause of the symptoms, I used DXplain which is a
computerized differential diagnosis generator:
"DXplain is a computer program designed to provide quick, easy access
to a large database of signs, symptoms, and diagnoses, and to remind
the user of disorders which might be associated with a set of clinical
features. The database used by DXplain includes many common and rare
diseases,but should not be considered complete due to a number of
causes, including but not limited, to a lack of complete coverage of
all signs, symptoms, laboratory tests, and diseases, and inaccuracies
in relationships of clinical findings to disease entities."
I typed the following into the program:
extremity muscle weakness, extremity muscle numbess, extremity
paresthesias (i.e. pins and needles), muscle spasm, constipation.
This resulted in the following diagnoses:
1) sciatic neuropathy
2) spinal cord compression
3) multiple sclerosis
4) intervertebral disc rupture (nerve root syndromes)
5) spinal stenosis
I will briefly discuss each disease entity.
1) Sciatic Neuropathy
"Sciatic neuropathy occurs due to a variety of causes. The most common
cause for compression or injury to the sciatic nerve in this region is
trauma, including hip dislocation, fracture, or replacement. Other
etiologies include wayward buttock injections, compression by external
sources such as prolonged bed rest (eg, coma), and any deep-seated
mass in the pelvis, including hematomas.
In addition to complaining of pain, patients with significant injury
to the sciatic nerve in this region also complain of weakness
affecting most of the lower leg musculature, including the hamstrings.
Hip flexion, extension, abduction and adduction, and knee extension
are normal. Sensory loss involves the entire peroneal, tibial, and
sural territories. In the lower leg, however, the medial calf and arch
of the foot may be spared secondary to innervation by the preserved
saphenous nerve (a branch of the femoral nerve). Sensation is also
spared above the knee both anteriorly and posteriorly. The knee jerk
is normal, but the ankle jerk is unobtainable.
Compression of the sciatic nerve may not produce significant
abnormalities on EMG unless it is relatively severe. Reduced peroneal
and sural sensory responses and a normal saphenous sensory response
are identified in more severe cases. Tibial and peroneal motor
response amplitudes also are reduced. A denervation/reinnervation
pattern in muscles subserved by the nerve, including the hamstrings,
The prognosis of sciatic neuropathy is generally favorable. In one
study, patients had a 75 percent overall likelihood of good recovery
without treatment over a three-year period. Absence of paralysis in
foot plantar and dorsiflexion at initial evaluation was a favorable
prognostic sign." (1)
2) Spinal Cord Compression
"Neoplastic epidural spinal cord compression (ESCC) is a common
complication of cancer that causes pain and sometimes irreversible
loss of neurologic function.
Pain is usually the first symptom of ESCC, being present in 83 to 95
percent of patients at the time of diagnosis (2). On average, pain
precedes other neurologic symptoms of ESCC by seven weeks. Affected
patients usually notice a severe local back pain which progressively
increases in intensity. Pain is often worse with recumbency, a feature
attributed to distension of the epidural venous plexus.
Weakness is present in 60 to 85 percent of patients with ESCC at the
time of diagnosis (2). ESCC generally produces fairly symmetric lower
extremity weakness. The progression of motor findings until diagnosis
typically consists of increasing weakness followed sequentially by
loss of gait function and paralysis (2). Sensory findings are a
little less common than motor findings but are still present in a
majority of patients at diagnosis (2). Patients frequently report
ascending numbness and paresthesias if questioned and examined
carefully. Bladder and bowel dysfunction due to ESCC is generally a
late finding that may be present in as many as one-half of patients
3) Multiple Sclerosis
Sensory symptoms are a common initial feature of MS and are present in
almost every patient at some time during the course of disease.
Symptoms are commonly described as numbness, tingling,
pins-and-needles, tightness, coldness, or swelling of the limbs or
trunk. Radicular pains also can be present, particularly in the low
thoracic and abdominal regions. An intensely itching sensation,
especially in the cervical dermatomes and usually unilateral, is
suggestive of MS. The most common sensory abnormalities on clinical
1) Varying degrees of impairment of vibration and joint position sense
2) Decreased pain and light touch perception in a distal distribution
in the four extremities
Patchy areas of reduced pain and light touch perception in the limbs
Patients also frequently report that the feeling of pinprick is
increased or feels like a mild electric shock, or that the stimulus
spreads in a ripple fashion from the point at which it is applied.
Physical findings include spasticity, usually more marked in the legs
than in the arms. The deep tendon reflexes are exaggerated, sustained
clonus may be elicited, and extensor plantar responses are observed.
All of these manifestations are commonly asymmetrical.
"Bowel, bladder, and sexual dysfunction are common in MS . . .
Constipation is more common than fecal incontinence." (4)
4) Nerve Root Syndromes
These include diseases of the lower back, such as spondylolisthesis, a
herniated disc, and lumbar spinal stenosis. The symptoms for each
disease depends on where on the spine is the injury.
"Involvement of S1
Leg pain is often worse than low back pain with involvement of S1. The
characteristic findings include:
- Pain and paresthesias are felt in the buttock, posterior thigh,
posterolateral calf and heel, and sometimes in the lateral foot and
last two toes
- Numbness and pinprick hypalgesia may be in the fifth toe, lateral
foot, and, to a lesser degree, in the posterolateral calf and
- There may be weakness of toe flexors and gastrocnemius, and rarely
of hamstrings, toe abduction, and eversion of the foot
- The ankle jerk is often diminished or absent.
Involvement of L5
Low back pain is often worse than leg pain with L5 disease. The
characteristic findings include:
- Pain and paresthesias radiate to the posterolateral thigh, groin,
lateral calf, dorsomedial foot and first two toes
- Numbness and hypalgesia may be found in the great toe, medial foot,
and, to a lesser extent, the anterolateral calf
- Weakness may be noted in extensor hallucis longus, tibialis
anterior, and peroneii, causing a foot drop
- There is usually no reflex loss
Involvement of L4 or L3
Low back pain is worse than leg pain in this setting. Other findings
that may be present include:
- Pain and paresthesias that radiate to the anteromedial thigh and
- Numbness and hypalgesia over the anteromedial thigh and knee
- Weakness in the quadriceps and iliopsoas muscles
- Diminished or absent knee jerk" (5)
5) Spinal Stenosis
From Medline Plus:
"Spaces within the spine can narrow without producing any symptoms.
However, if narrowing places pressure on the spinal cord or nerve
roots, there may be a slow onset and progression of symptoms. The back
itself may or may not hurt. More often, people experience numbness,
weakness, cramping, or general pain in the legs that occurs during
flexing the lower back while sitting. (The flex position "opens up"
the spinal column, enlarging the spaces between vertebrae at the back
of the spine.) If a disk between vertebrae is compressed, people may
feel pain radiating down the leg (sciatica).
People with more severe stenosis may experience abnormal bowel and
bladder function and foot disorders. For example, cauda equina
syndrome is a partial or complete loss of control of the bowel or
bladder and sometimes sexual function; it is due to compression of the
collection of spinal roots that descend from the lower part of the
spinal cord and occupy the vertebral canal below the cord. In very
rare instances, compression above the area where the lumbar vertebrae
and sacrum meet results in partial or complete paralysis of the legs."
I stress that this answer is not inteneded as and does not substitute
for medical advice - please see your primary care physician for
further evaluation of your individual case. I am not trying nor do I
want to diagnose what you have - this answer is merely possible
diseases that fit the constellation of symptoms you described.
I will be happy to research the evaluation and treatment of any of the
disease I mentioned in seperate questions.
Please use any answer clarification before rating this answer. I will
be happy to explain or expand on any issue you may have.
Internet search strategy:
No internet search engine was used in this research. All sources were
from objective physician-written and peer reviewed sources.
1) Rutkove, S. Overview of the lower extremity nerve syndromes.
2) Helweg-Larsen, S, Sorensen, PS. Symptoms and signs in metastatic
spinal cord compression: A study of progression from first symptom
until diagnosis in 153 patients. Eur J Cancer 1994; 30A:396.
3) Schiff, D. Clinical features and diagnosis of epidural spinal cord
compression, including cauda equina syndrome. UptoDate, 2002.
4) Olek, M. Epidemiology, risk factors and clinical features of
multiple sclerosis. UptoDate, 2002.
5) Lehrich, J. Approach to the diagnosis and evaluation of lower back
pain in adults. UptoDate, 2002.
Merck Medicus - Multiple Sclerosis
Merck Medicus - Peripheral Neuropathy
Medline Plus - Spinal Stenosis
Medline Plus - Sciatica
Medline Plus - Slipped Disk