782THE JOURNAL OF BONE AND JOINT SURGERY
Observations on the natural history of
massive lumbar disc herniation
G. L. Cribb,
D. C. Jaffray,
V. N. Cassar-
From the Robert
Jones and Agnes
? G. L. Cribb, FRCS(Tr & Orth),
? D. C. Jaffray, FRCS,
? V. N. Cassar-Pullicino, FRCR,
Robert Jones and Agnes Hunt
Oswestry, Shropshire SY10
Correspondence should be sent
to Miss G. L. Cribb; e-mail:
©2007 British Editorial Society
of Bone and Joint Surgery
J Bone Joint Surg [Br]
Received 28 September 2006;
Accepted after revision 2 March
We have treated 15 patients with massive lumbar disc herniations non-operatively. Repeat
MR scanning after a mean 24 months (5 to 56) showed a dramatic resolution of the
herniation in 14 patients. No patient developed a cauda equina syndrome.
We suggest that this condition may be more benign than previously thought.
Most herniated lumbar discs resolve spon-
taneously.1-8 Although smaller herniations may
be safely treated non-operatively, massive
extrusions and sequestrations are sometimes
treated by operation for fear of cauda equina
compression. We present the clinical and
radiological outcome of 15 patients who were
treated conservatively having presented with
leg pain and a massive lumbar disc herniation.
Patients and Methods
We have reviewed 15 patients with a massive
lumbar disc herniation and a painful radicul-
opathy who chose not to have surgery. They
presented to a general spinal clinic over a
period of five years. There were ten women
and five men, with a mean age of 45 years (24
to 73). Ten herniations were at the L4-5 level
and five at L5-S1. The reason the patients
chose to be treated without operation was
either that their symptoms had started to
improve spontaneously, that they feared surgi-
cal complications, or both. To qualify as a
‘massive’ herniation at least 50% of the spinal
canal had to be occluded by disc material on
axial MRI scans. The anteroposterior dia-
meters of the spinal canal and of the disc were
measured and the latter expressed as a per-
centage of the former. The patients were
advised to return for emergency discectomy
should they develop features of a cauda equina
syndrome. Otherwise they were asked back for
clinical review and a repeat MR scan. These
scans were performed at a mean of 24 months
(5 to 56) after the initial scan. All were per-
formed without gadolinium enhancement.
The following criteria were used to distin-
guish protrusion from extrusion. The disc
herniation was deemed to be a protrusion if the
greatest distance, in any plane, between the
edges of the disc material beyond the disc space
was less than the distance between the edges of
the base in the same plane. A disc extrusion
was deemed to be present if any one distance
between the edges of the disc material beyond
the disc space was greater than the distance
between the edges of the base measured in the
same plane. An extrusion was designated a
sequestration if the displaced disc material had
completely lost continuity with the parent
All 15 disc herniations were classified as extru-
sions, six of which were sequestrations. All
were uncontained as there was no surrounding
The mean percentage of the canal occupied
by disc on an axial MR scan was 66% (55% to
80%). All but one herniation had resolved
dramatically by the time of the second MR
scan (Fig. 1). The reduction in size of the her-
niation on MRI was a mean of 80% (68% to
One patient needed a discectomy because of
persistent pain, despite substantial resolution
of the disc prolapse on MRI. In another patient
whose disc had not resolved radiologically, the
symptoms had diminished to such an extent
that surgery was not required.
No patient developed a cauda equina syn-
In 1983, Weber1 showed that the natural his-
tory of radiculopathy because of lumbar disc
herniation is to clinical resolution. Surgery car-
ried out in the first year gave earlier relief of
pain, but thereafter the results of surgery were
the same as those of non-operative treatment.
OBSERVATIONS ON THE NATURAL HISTORY OF MASSIVE LUMBAR DISC HERNIATION783
VOL. 89-B, No. 6, JUNE 2007
Weber’s study predates MR scanning, and it is understand-
able that there was no myelographic follow-up to see the
radiological outcome of non-operative treatment. There
may well have been massive herniations in that series, but it
is likely that they would have formed a tiny proportion of
the overall number, just as we find in our practice.
The spontaneous resolution of lumbar disc herniation
has been demonstrated both on CT scanning2,5,6 and
clinically.3,10 Jensen et al8 studied the changes in disc
morphology in 154 patients with sciatica who were
treated non-operatively. They found that broad-based
protrusions, extrusions and sequestrations improved
more than bulges and focal protrusions. They concluded
that nerve root compromise had the best prognosis if the
disc was extruded on the baseline MR scan. Porter,
Hibbert and Wicks11 examined the size of the spinal
canal and showed that patients with small canals at the
L5 level were more likely to require discectomy. There
was no relationship between the type of herniation, pro-
trusion or sequestration and canal diameter in those who
underwent surgery. The authors did not examine the size
of the disc herniations. In our study we examined the size
of the herniation in relation to the diameter of the canal.
It would be interesting to extend this and compare canal
size in our cohort of patients to a matched group of
patients with massive disc herniations who required sur-
There are two studies7,10 which have shown that larger
disc herniations decrease in size and to a greater extent than
do smaller protrusions.
Bozzao et al7 had eight patients in their series of 69 with
disc herniations which occupied more than 50% of the
canal. Six of these had reduced in size by more than 70% on
follow-up axial MR scans.
The dramatic resolution of these massive extrusions is
probably due to the loss of the immune privilege that the
normal disc enjoys when covered by the outer annulus.
Only when the disc ruptures are macrophages in the epid-
ural space free to act on the disc material. Nevertheless, the
ability of the body to clear the spinal canal of a massive
extrusion is impressive.
The fear of a missed cauda equina syndrome prompts
some surgeons to operate on massive discs. This fear may
be misplaced. In our admittedly limited study, treating mas-
sive extrusions non-operatively did not result in complica-
tions. Surgery for lumbar disc herniation, by contrast, is not
uncomplicated. The rate of recurrence in our institution is
7.9%12 requiring further and more difficult surgery
through dense scar tissue surrounding the affected nerve
root. An audit of discectomies by the British Association of
Spine Surgeons13 revealed a leak of cerebrospinal fluid in
3.5% of primary discectomies and 13.2% with revision dis-
cectomy. Infection rates of up to 3% have been reported,14
and death or serious injury through intra-abdominal vascu-
lar or visceral perforation has been described in 21 cases by
Goodkin and Laska.15
Although massive herniations are rarely left alone for
well-understood reasons, this small cohort of patients
reveals a more benign side to this pathology which may not
always deserve its fearsome reputation.
No benefits in any form have been received or will be received from a commer-
cial party related directly or indirectly to the subject of this article.
1. Weber H. Lumbar disc herniation: a controlled, prospective study with ten years of
observation. Spine 1983;8:131-40.
2. Bush K, Cowan N, Katz DE, Gishen P. The natural history of sciatica associated
with disc pathology: a prospective study with clinical and independent radiological
follow-up. Spine 1992;17:1205-12.
3. Saal JA, Saal JS. Nonoperative treatment of herniated lumbar intervertebral disc
with radiculopathy: an outcome study. Spine 1989;4:431-7.
4. Awad J, Moskovich R. Lumbar disc herniations: surgical versus nonsurgical treat-
ment. Clin Orthop 2006;443:183-97.
5. Fagerlund MKJ, Thelander U, Friberg S. Size of lumbar disc hernias measured
using computed tomography and related to sciatic symptoms. Acta Radiol
6. Teplick JG, Haskin ME. Spontaneous regression of herniated nucleus pulposus.
AJR Am J Roentgenol 1985;6:371-5.
7. Bozzao A, Gallucci M, Masciocchi C. Lumbar disc herniation: MR imaging
assessment of natural history in patients treated without surgery. Radiology
8. Jensen TS, Albert HB, Soerensen JS, Manniche C, Leboeuf-Yde C. Natural
course of disc morphology in patients with sciatica: an MRI study using a standard-
ized qualitative classification system. Spine 2006;31:1605-12.
9. Fardon DF, Milette PC. Nomenclature and classification of lumbar disc pathology.
10. Saal JA, Saal JS, Herzog RJ. The natural history of lumbar intervertebral disc
extrusions treated nonoperatively. Spine 1990;15:683-6.
Resolution of a massive extrusion with disc sequestration after six
784G. L. CRIBB, D. C. JAFFRAY, V. N. CASSAR-PULLICINO Download full-text
THE JOURNAL OF BONE AND JOINT SURGERY
11. Porter RW, Hibbert CS, Wicks M. The spinal canal in symptomatic lumbar disc
lesions. J Bone Joint Surg [Br] 1978;60-B:485-7.
12. Morgan-Hough CV, Jones PW, Eisenstein SM. Primary and revision lumbar dis-
cectomy: a 16-year review from one centre. J Bone Joint Surg [Br] 2003;83-B:871-4.
13. Tafazal SI, Sell PJ. Incidental durotomy in lumbar spine surgery: incidence and man-
agement. Eur Spine J 2005;14:287-90.
14. Rohde V, Meyer B, Schaller C, Hassler WE. Spondylodiscitis after lumbar dis-
cectomy: incidence and a proposal for prophylaxis. Spine 1998;23:615-20.
15. Goodkin R, Laska LL. Vascular and visceral injuries associated with lumbar disc
surgery: medicolegal implications. Surg Neurol 1998;49:358-72.