BMJ Paper
Title:
Triage of GP referrals with low back pain in inner city Bristol: audit of a ‘one stop’ investigation and
assessment service.
Authors:
David R Sandeman, Consultant Neurosurgeon and Medical Director, South West Imaging Services Ltd
Keith Greenfield, Spinal physiotherapist
Marcus Bradley, Consultant Neuroradiologist
Institution:
Department of Neurosurgery, Frenchay Hospital, Frenchay Park Road, Bristol, BS16 1LE
Affiliation:
South West Imaging Services (SWIS) Ltd, Department of Neurosurgery, Frenchay Hospital, Bristol,
BS16 1LE
Abstract:
Objectives:
To examine the efficacy of a ‘one stop’ spinal assessment service where all patients
referred for specialist opinion underwent lumbar MRI scanning followed by immediate specialist
assessment.
Design:
Prospective audit of a pilot service run for Bristol Primary CareTrust (PCT) from April
2007 until October 2009 for North Bristol General Practitioners.
Setting:
Primary care based assessment of low back pain referrals by spinal specialists
Participants: North Bristol GP practices, secondary care spinal clinicians – spinal physiotherapists,
Neurosurgeons and Neuroradiologists, employed by SWIS Ltd
Main outcome measures:
Provision and speed of delivery of spinal assessment, analysis of
spinal pathology identified, discrepancy between clinical and radiological analysis of imaging and
analysis of onward referral of the patients assessed, including follow up rates
Results:
2543 patients were referred in the 31 months of the pilot, an average of 85 per
month (Range 50 – 110 per month). Of these 2372 were assessed (93%). 2259 were assessed with
imaging (95%). 1046 patients were assessed by a consultant neurosurgeon (44%), 1326 by a spinal
physiotherapist (56%). 1045 had surgical pathology on their scans (44%), 555 had a disc
prolapse(23%), 287 had lumbar stenosis (12%) and 142 had spondylolithesis (6%). Previously
undisclosed congenital abnormality or scoliosis were identified in 25 cases; fractures including
osteoporotic collapse were found in 25 cases and undisclosed spinal tumours in 11 cases. Non
surgical pathology was found in 1327 cases (56%) – age related degenerative change in 1138 cases
(44%), normal scans in 175 patients (7%) and 14 patients with non spinal pathology. Discrepancies
between the clinical interpretation of the scan and the radiology report were identified in 69 cases
(3%). Pathology was missed in 48 cases – in 29 by the clinician and in 19 by the radiologist. Scans
were over interpreted by the clinician in 6 cases . Administrative errors were identified in 15 cases.
1211 patients (51% of the total assessed) were managed in primary care. 689 were discharged back
to the care of their GP’s (29%). 151 patients with surgical pathology but whose symptoms were
improving were offered follow up by SWIS Ltd (6%). 179 patients were referred for physiotherapy
(7.5%) and 192 patients referred to a community based back pain service (8%). Of the 1161 patients
referred to secondary care (49% of the total assessed), 294 were referred directly for surgery (12%),
619 to the pain clinic (26%), for further spinal specialist assessment (13%), either orthopaedic (69)
or Neurosurgical (232). 11 patients were referred for other secondary opinion – urology, neurology,
rheumatology and general surgery.
The mean time from receipt of referral to assessment of the patient was 23 days.
212 patients were followed up (9%), either planned (129), or as part of an open follow up policy for
patients with surgical pathology (28) or following referral by their GP or the pain clinic (55). Closure
in a single assessment was therefore obtained in 2160 cases (91%).
Conclusion
44% of patients with low back pain referred by GP’s for specialist assessment have
surgical pathology on MRI scans. ‘One stop’ triage of GP referrals by spinal specialists produces
closure in a single visit of over 90% of cases with 50% of patients being managed in primary care.
Referrals of the other 50% are to the appropriate secondary care facility. A universal MRI scanning
policy when combined with specialist assessment, is both cost effective and informative and
becomes an intregral part of patient management. Timely assessment of patients results in optimal
timing of treatment for those patients that need intervention. The current NICE guidelines for back
pain management are confusing and should be rewritten on the basis of this data
Introduction:
Low back pain is recognised as the single largest cause of loss of word days worldwide (1). A
distinction is made between simple back pain – self limiting pain of musculoskeletal origin that
settles within a few weeks almost irrespective of the treatment applied, complex back pain where
prolonged pain starts to inflict on a patient’s life and other spinal symptoms like sciatica (ref). GP’s
are adept at managing patients in the first category. However when back pain persists beyond a few
weeks, when it is associated with sciatica or when it is clearly associated with a complex pain
syndrome, they will often seek specialist help.
This paper reports a primary care based specialist assessment service, run as a pilot study for the
Bristol Primary care Trust (PCT) by South West Imaging Service (SWIS) Ltd from April 2007 until
October 2009.
SWIS Ltd was founded in 2005 with the specific remit of streamlining MRI based diagnostic services
combining MR imaging with a specialist opinion, the so called ‘one stop shop’. This service was
delivered for self pay patients in the first instance. The NHS contract awarded by Bristol PCT after
competitive tender began in April 2007.
The terms of reference of the contract were as follows. The service was to be run as a pilot for north
Bristol GP’s serving a population of 250,000 covering inner city Bristol. The service was mainly to be
for patients managed in primary care first for a mimimum of six weeks, although patients with
severe symptoms could be referred earlier. Patients with a known diagnosis of scoliosis were
specifically excluded from the service.
Methods:
All referrals were collated by the Bristol Primary Care Trust (PCT) first before onward referral to SWIS
by fax. A senior clinician at SWIS then triaged each referral with respect to urgency – a routine
referral was booked within one month of receipt of the referral, a referral to be seen soon was
booked within one week. If a case was urgent arrangements were made for same day review.
Referrals were also triaged with respect to the reviewing specialist. Surgical cases, in general those
where sciatica was their main symptom were designated for review by a surgeon and non surgical
cases (back pain alone) were reviewed by a spinal physiotherapist. The majority however were
designated to be reviewed by either specialist. Patients were contacted first by phone, then by
letter. If they failed to respond to a letter, their contact details were checked with the referring GP. A
patient was deemed uncontactable if they failed to contact the service after referral back to their
GP’s.
The spinal physiotherapist (KG) had an 18 year experience in the assessment of spinal patients,
receiving his initial training in the early 1990’s in the clinic of the late Huw Griffith, consultant
neurosurgeon. Dr Green field has a PhD is in spinal management. The lead surgeon, (DRS) is a
consultant neurosurgeon of 19 years standing with subspecialist interests that include pain and
spinal surgery. He is medical director of SWIS Ltd. All other specialists involved in assessments were
consultant neurosurgeons at Frenchay Hospital in Bristol.
Most of the radiology reporting was carried out by consultant Neuroradiologists at Frenchay
hospital, although in the early part of the study some was outsourced for remote reporting by
general spinal radiologists. The discrepancy reporting was carried out by the lead Neuroradiologist
(MB) and Neurosurgeon (DRS)
Where possible all patients were assessed following standard sequence supine MRI scans of their
lumbar spines, carried on 1.5T Scanners – i.e. T1 and T2 sagittal and T2 axial images. ‘Batching’
imaging of the same area allowed for efficient turn round of patients in a dedicated scan session of
three hours, scanning nine patients per session or three per hour.
Dedicated spinal clinics were run in parallel to the scan sessions so that patients were seen straight
away by the appropriate spinal specialist who had immediate access to the imaging. They were then
triaged into the appropriate management group.
Radiology reports were provided within 48 hours of the scan. Subsequent comparison of the report
with the clinician’s interpretation of the MRI, documented in the clinic letter was then carried out by
a senior clinician (DRS), potential discrepancies identified and those cases reviewed in a joint clinical
/ neuroradiological review meeting. Discrepancies were then characterised according to Royal
College of radiologists guidelines (ref)
Index of Multiple Deprivation (IMD) data from the department of work and pensions which matches
a ‘deprivation score’ to postcode was used to define the population base for the pilot.
Results:
Patient base.
SWIS Ltd received a total of 2543 referrals over the 31 month period of the pilot from 35 GP
practices in North Bristol. The quintile IMD score for the base population defined by the postcodes
of these GP practices was compared to the IMD score of the patients seen – Table 1. Whereas there
was a fairly even distribution of IMD scores in the base population, in the referral group there was a
heavy bias towards the most deprived groups, 74% coming from the most deprived areas – quintile 1
and 2 with only 6% coming from the least deprived – quintiles 4 and 5.
Of the total, 2372 patients were actually seen (93%). 72 patients did not attend – DNA, (3%). A
further 99 patients were not contactable (4%).
Triage
363 patients were triaged into the ‘surgical’ group i.e. to be seen by a neurosurgeon (14%). The
predominance of sciatica as a presenting symptom was the usual reason for inclusion in this group,
although factors such as previous surgery or a clear history from the GP that symptoms were
exercise related were also considered. 306 patients (12%) were triaged to be reviewed by the
physiotherapist. These were patients in whom there was a clear history of low back alone. The
majority however (1874 patients) were triaged to be seen by either specialist (74%)
2395 patients (94%) were triaged to be seen routinely i.e. within one month of referral. 138 were
triaged as soon – to be seen within 1 week of referral (5%). Despite the remit for referral, 10 patients
were processed as urgent cases, the same day as referral, usually because of cauda equina
symptoms.
The overall mean waiting time from receipt of referral by SWIS to appointment was 23 days.
Diagnosis
Except where patients were assessed with scans already done (185 cases), the diagnosis was made
primarily by the assessing clinician, interpreting the MRI scans themselves. Radiologist reports were
obtained within 48 hours and then compared retrospectively to the clinician’s findings by the study’s
lead surgeon (DRS). Where a discrepancy was identified each case was discussed with the lead
radiologist (MB). In 2006 cases there was no discrepancy. 106 cases were reviewed. In 37 of these no
error was identified on review. Pathology was missed in 48 cases – in 29 by the clinician and in 19 by
the radiologist. Scans were over interpreted by the clinician in 6 cases and the pathology described
by them not confirmed by the radiologists. Administrative errors were identified in 15 cases. The
majority of these were minor typographic errors that led to the reports being ambiguous (11 cases)
but in two the pathology was described at the wrong level, in one the side of the pathology was
recorded wrongly and in one a report was assigned to the wrong patient.
Using the Royal College of Radiologists criteria these discrepancies were classified as major, resulting
in a major change in management, moderate, resulting in a minor change in management and
minor, resulting in no change in management. By this definition there were 2 major errors, 26
moderate errors and 41 minor errors.
In 1045 patients (44%) surgical pathology was identified. 555 had a disc prolapse(23%), 287 had
lumbar stenosis (12%) and 142 had spondylolithesis or a pars defect (6%). Previously undisclosed
congenital abnormality or scoliosis were identified in 25 cases; fractures including osteoporotic
collapse were found in 25 cases and undisclosed spinal tumours in 11 cases. (Table 2)
Non surgical pathology was found in 1327 cases (56%) – age related degenerative change in 1138
cases (44%), normal scans in 175 patients (7%) and 14 patients with non spinal pathology. (Table 2)
Onward referral
1211 patients (51% of the total assessed) were managed in primary care. 689 were discharged back
to the care of their GP’s (29%). These patients received a diagnosis, an explanation for their
symptoms and advice on management. 151 patients with surgical pathology but whose symptoms
were improving were offered follow up by SWIS Ltd (6%). 179 patients were referred for
physiotherapy (7.5%) and 192 patients referred to a community based back pain service run by pain
psychologists and physiotherapists (8%).
1161 patients (49% of the total assessed) were managed in secondary care. 294 were referred for
surgery (12%), 196 for lumbar microdiscectomy, 79 for stenosis surgery, six for tumour surgery and
13 for vertebroplasty. 163 were referred for further spinal specialist assessment (7%) either by
neurosurgeons or by spinal orthopaedic surgeons. 93 were referred for evaluation of possible
instability, usually following a radiological diagnosis of lithesis . 46 patients required other further
investigation – CT scans +/- myelography in 8 patients, open MRI or MRI under sedation in 16
claustrophobic patients and exclusion of metallic foreign bodies in two. 16 patients required
investigation of their cervicodorsal spines, outside the remit of the back pain service, two required
pelvic ultrasound, one a contrast enhanced MRI and one a bone scan. 18 patients were referred for
follow up in secondary care. Six patients with a previously undiagnosed congenital abnormality
were referred to a spinal dysraphism specialist.
A total of 131 patients were referred for root block (5.5%), 57 via the pain clinic and 74 via
neurosurgery to be performed by the interventional spinal neuroradiologists. There were two
indications for an X ray targeted root block, early treatment of severe sciatica from a moderate disc
prolapse or for diagnostic purposes in the uncommon situation where a patient had sciatica in the
presence of two disc prolapses. In general those patients with complex pain syndromes were
referred to the pain clinic but since the neuroradiology department was able to respond more
quickly to requests, this became a factor determining referral, particularly towards the end of the
study period.
562 other patients were referred to the pain clinic (24%), primarily for the non surgical management
of complex pain syndromes.
11 patients were referred for other specialist opinion (0.5%) – urology, neurology, rheumatology and
general surgery.
Follow up
The back pain assessment service followed patients up in three circumstances:
1. Patients with surgical pathology whose symptoms were thought likely to settle with time
were sent a follow up appointment for reassessment – this was offered in 151 patients
2. Patients with surgical pathology whose symptoms were improving at the time of assessment
were offered an open appointment for follow up – this was offered in 248
3. Any patient discharged from the service was reviewed at their GP’s request – total 689
patients
A total of 212 patients were followed up, 129 planned follow up (85% of appointments offered), 28
with an open follow up appointment (11%) and 55 re-referred by their GP’s or the pain clinic (4%).
Closure in a single assessment was therefore obtained in 2160 cases (91%). Table 3
Discussion:
The NICE guidelines on the management of back pain suggest that the majority of patients that
attend their GP’s with symptoms relating to their lower back do not have serious pathology. The
guidelines recommend a non interventionist approach. This paper reveals that the opposite is true
for the cohort of patients that have failed simple management by their GP’s and still have disabling
symptoms 6 weeks after presentation. Nearly half (44%) of these patients had surgical pathology.
When assessed by specialists with an understanding of the role of surgery only 12% actually required
surgery. The rest were managed conservatively following informed specialist advice, with over 90%
of patients receiving closure in a single assessment. The majority of the patients without surgical
pathology had age related degenerative change on their scans. Only 7% had normal scans, the same
number that had spondylolithesis or a pars defect! The identification of life changing symptoms in
the presence of normal imaging immediately allowed this group of patients to be identified as
having a complex pain syndrome, triggering appropriate onward referral.
It is commonly said that ‘over investigation’ of patients with simple back pain is detrimental. In
models of care where imaging is divorced from the specialist assessment and where images are
reported by non specialist radiologists often without English as their first language, this may be the
case. However the exact opposite was found in this study. When scanning was followed immediately
by specialist assessment the ability to give patients an informed opinion on their condition and to
advise them accordingly both alleviated their fears (a significant number of patients thought they
had cancer!) and started the therapeutic process. It provided the basis for informed discussion to
take place on change of life style, weight loss and the need for core stability exercise particularly in
those patients with age related degenerative change.
The demographics of referral are worthy of comment. Why was it that 75% of patients seen in this
study were from the most socially deprived areas when the population base had equal numbers of
patients in each social deprivation group? It is likely that patients in the higher social deprivation
groups had more disposal income and were therefore more likely to access private health care,
alternative care or self pay assessment services such as the core activity of SWIs Ltd. The fact that
the study targeted the most needy in society and the most likely to access public funds for their day
to day care is further evidence of the efficacy of this approach.
Traditionally services for back pain patients were very unresponsive to their needs with long waiting
times for every stage of assessment, to see a specialist, for imaging, for review by the specialist and
then for treatment. Overall waiting times from referral to surgery commonly exceeded two years!
Indeed it was to offer an alternative to this that SWIS one stop service was originally set up. In
parallel to back pain service run by SWIS, North Bristol NHS trust set up a generic spinal waiting list
allowing patients access to surgery within 3 months of referral, an overall wait from referral to
treatment of 15 weeks complying with government targets. It seems that timely surgery results in
improved efficiency in the use of resources as 78% of patients under 65 years old undergoing
discectomy or posterior lumbar decompression surgery were treated as day cases (unpublished
observation)
A criticism that can be made of the service relates to the role of supine MRI scanning alone as the
primary diagnostic tool. Either overt or potential spinal instability may be missed if weight bearing
plain films are not carried out in appropriate cases. In this study patients with spondylolithesis and
or pars defects were referred on for further assessment in secondary care. Patients with known
scoliosis were specifically excluded from the study. When previously undisclosed scoliosis was
diagnosed these patients were also referred onto secondary care for assessment by a scoliosis
surgeon. However the diagnosis could only be made on coronal scout MRI views. A further study will
analyse the results of posterior lumbar decompression surgery in patients referred from this study.
Anecdotal evidence suggests that some patients have suffered post surgical instability. Dynamic
investigation on all patients with lumbar stenosis or lateral recess stenosis should be also be
considered, 20% of patients seen in this study. This might make a case for a weight bearing MRI scan
being used as the screening investigation.
There is considerable doubt as to the efficacy of lumbar epidural injections in the treatment of low
back pain. In this study untargeted epidural injections were not used. Targeted X ray guided root
blocks were used in two situations; to alleviate acute sciatica of short duration that was expected to
settle spontaneously and as a diagnostic tool in patients with pathology at more than one level in
the spine. To be useful they must be carried out in a timely fashion ideally within a week of referral.
An audit of the results of root blocks in this study will be published separately.
Finally this data gives a clearer understanding of the resources needed to provide a comprehensive
back pain service. The pilot study served a population base of 250,000. This generated 85 referrals a
month, half of which required secondary care services, including 7 root blocks, 10 discectomy or
decompression operations per month and up to 2 stabilisation procedures a month. Accurate
planning like this could lead to the ring fencing of resources with increased efficiency and cost
savings.
Conclusion
1. 44% of patients with low back pain referred by GP’s for specialist assessment have surgical
pathology on MRI scans.
2. ‘One stop’ triage of GP referrals by spinal specialists produces closure in a single visit of over
90% of cases
3. 50% of patients can be managed in primary care.
4. Referrals of the other 50% are to the appropriate secondary care facility.
5. A universal MRI scanning policy when combined with specialist assessment, is both cost
effective and informative and becomes an intregral part of patient management.
6. Timely assessment of patients results in optimal timing of treatment for those patients that
need intervention.
7. The current NICE guidelines for back pain management are confusing and should be
rewritten on the basis of this data
Acknowledgements:
References:
1. Erhlich G J Rheumatol Suppl. 2003 Aug;67:26-31
2. RCR – Standards for radiology discrepancy meetings
3. NICE guidliens for Back pain management – May 2009
IMD Quintile by postcode
1
2
3
4
5
% North Bristol GP’s overall
20
22
18
22
18
% Patients referred to SWIS
50
24
17
4
2
Table 1: Index of multiple deprivation scores relating to postcode – Department of Work and
Pensions data 2007. Comparison of the percentage of each quintile in referral group with
the distribution in the base population
Pathology type
Surgical
Non surgical
Pathology
Disc prolapse
Stenosis
Lithesis / Pars defect
Scoliosis
Fracture
Congenital
Tumour
Spondylosis
Normal scan
Extra spinal
Total
Number
556
288
142
16
26
10
11
1133
176
14
2372
Percentage
23
12
6
1
1
0.5
0.5
48
7
1
100
Accepted
129
28
55
212
Percentage
85
11
8
9
Table 2: Pathology identified on MRI scanning
Type
Planned
Open
Re-referral
Total
Table 3: Follow up
Offered
151
248
689
2372