3.3 Lumbar spine surgery hospital admissions Context This data item examines hospital admissions for lumbar spine surgery for people. Hospital admission data are sourced from the Admitted Patient Care National Minimum Data Set. This includes both public and private hospitals. Rates are described as the number of admissions per 100,000 people. Repeat admissions for one person and transfers to other hospitals are both counted as separate admissions. Lumbar spine surgery refers to any type of surgery in the lumbar spine or lower back. Most admissions for back surgery are for people aged 45 years and over. 1 Two common procedures are decompression and fusion. Lumbar spine decompression (often termed laminectomy ) is undertaken to relieve pain caused by nerve root pressure, usually caused by a herniated disc or spinal stenosis. It may involve removal of any or a combination of, herniated disc material, bone, thickened ligaments and arthritic facet joints in order to free trapped nerves. The indications for decompression surgery are well developed and accepted. 2 Lumbar spine fusion surgery is performed to stabilise the spine, sometimes in combination with decompression surgery. It is also performed for painful degenerative conditions, deformity (scoliosis and spondylolisthesis) and trauma. Despite the increasing rate of fusion surgery, insufمحcient evidence is available to support its use for painful degenerative back conditions. 2 Spinal surgery is usually the last resort in the treatment of back problems. Most back problems are managed non-operatively by general practitioners, physiotherapists and other primary care health professionals. Australian Atlas of Healthcare Variation Surgical interventions 121
Lumbar spine surgery hospital admissions Magnitude of variation From 2010 11 to 2012 13, there were 17,305 lumbar spine surgery admissions to hospital on average per annum, representing 96 admissions per 100,000 people aged (the Australian rate). The estimated annual number of lumbar spine surgery admissions to hospital across 322* local areas (SA3s) ranged from 36 to 173 per 100,000 people aged. The number of admissions was 4.8 times higher in the area with the highest rate compared to the area with the lowest rate. The estimated annual average number of admissions varied across states and territories, from 60 per 100,000 people aged in the Australian Capital Territory, to 113 in mania. After excluding the highest and lowest results, the lumbar spine surgery hospital admission rate across the 297 remaining local areas was 2.3 times higher in one local area compared to another. Rates of admission for lumbar spine surgery were higher in inner regional areas than in major cities or outer regional areas, and lowest in remote areas. In major cities, inner regional areas and remote areas, rates increased with increasing socioeconomic status, but this socioeconomic correlation was not present in outer regional areas. Interpretation Potential reasons for the variation include differences in: clinicians adopting evidence-based practice in clinical decision making rates of private health insurance and access to private hospitals. Most lumbar spine surgery is performed in private hospitals. 3 Under-servicing in the public sector and over-servicing in the private sector could contribute to variation 3 patient and doctor preferences, particularly relating to lumbar spine fusion surgery the presence of risk factors for back pain such as obesity 4 the incidence and prevalence of back injury and back pain. No obvious explanation exists for the higher admission rates in regional centres compared to major cities, and it is not possible to state how much variation is unwarranted. In addition, it is unclear whether the considerably higher rates in some states correlate with the higher rates in regional centres in those states or whether they are due to other factors. To explore this variation, further analysis could focus on: identifying the reasons for the higher rates in regional centres accessing data that distinguishes between fusion and decompression surgery to help determine the extent to which variation represents clinician preferences, particularly relating to fusion surgery the inمخuence of the private and public sectors on rates of lumbar spine surgery potential under-servicing of people without private health insurance. Data on waiting times for public outpatient clinic appointments, the waiting-list time for an operation once seen, and the indications for and type of surgery performed in the public hospital system would be useful in this regard. This data would also need to be compared with that for people with private insurance the relationship between higher rates of surgery and access to non-surgical forms of treatment such as physiotherapy and pain clinics. * There are 333 SA3s. For this item, data were suppressed for 11 SA3s. This is because of conمحdentiality requirements given the small numbers of admissions in these areas. 122 Australian Commission on Safety and Quality in Health Care
Figure 37: Estimated annual number of lumbar spine surgery admissions to hospital per 100,000 people aged, age standardised, by local area, 2010 11 to 2012 13 For this item, local area refers to an ABS standard geographic region known as a Statistical Area Level 3 (SA3) The size of each circle represents the number of admissions in each local area 6 100 1 200 Lowest rate areas Highest rate areas 40 60 70 80 90 100 110 120 130 140 1 160 170 Lumbar spine surgery hospital admissions, by local area (each circle represents an area) Local area State Rate Admissions Local area State Rate Admissions Far North Alice Springs North Canberra Kimberley Outback - North and East Weston Creek Dandenong South Canberra Katherine Gungahlin Pilbara Port Adelaide - East Maribyrnong Port Adelaide - West Qld NT WA SA Vic NT WA SA Vic SA 36 39 42 49 52 53 53 53 54 55 56 58 59 8 11 15 11 12 11 74 11 8 16 29 28 32 28 Hobart - North East Wollondilly Camden Brighton Dural - Wisemans Ferry Eastern Suburbs - North Serpentine - Jarrahdale Southern Highlands Hobart - South and West Richmond - Windsor Sorell - Dodges Ferry WA 173 172 170 167 161 159 157 147 145 143 142 75 51 65 20 33 167 22 67 38 38 18 Notes: Rates are standardised based on the age structure of the Australian population in 2001. State/territory and national rates are based on the total number of admissions and people in the geographic area. The term local area refers to an ABS standard geographic region known as a Statistical Area Level 3 (SA3). Includes all public hospitals, private hospitals and day hospital facilities. The rate and number of admissions is the average per annum over three years. For more technical information please refer to the Technical Supplement. Sources: National Health Performance Authority analysis of Admitted Patient Care National Minimum Data Sets from 2010 11 to 2012 13 Australian Atlas of Healthcare Variation Surgical interventions 123
Lumbar spine surgery hospital admissions Figure 38: Estimated annual number of lumbar spine surgery admissions to hospital per 100,000 people aged, age standardised, by local area, 2010 11 to 2012 13 DARWIN BRISBANE PERTH SYDNEY CANBERRA 126 173 per 100,000 115 125 109 114 101 108 97 100 90 96 84 89 77 83 69 76 36 68 not available for publication For this item, local area refers to an ABS standard geographic region known as a Statistical Area Level 3 (SA3) ADELAIDE MELBOURNE HOBART Sources: National Health Performance Authority analysis of Admitted Patient Care National Minimum Data Sets from 2010 11 to 2012 13 124 Australian Commission on Safety and Quality in Health Care
The estimated annual number of lumbar spine surgery admissions to hospital across 322 local areas (SA3s) ranged from 36 to 173 per 100,000 people aged. The number of admissions was 4.8 times higher in the area with the highest rate compared to the area with the lowest rate. NEWCASTLE DARWIN SUNSHINE COAST SYDNEY PERTH BRISBANE ROCKINGHAM MANDURAH GOLD COAST WOLLONGONG CANBERRA ADELAIDE MELBOURNE GEELONG HOBART Sources: National Sources: N ational Health Performance Authority analysis of Admitted Patient Care National Minimum Data Sets from 2010 11 to 2012 13 Australian Atlas of Healthcare Variation Surgical interventions 125 interventions 125
Lumbar spine surgery hospital admissions Figure 39: Estimated annual number of lumbar spine surgery admissions to hospital per 100,000 people aged, age standardised, by local area, state and territory, 2010 11 to 2012 13 Vic Qld SA WA NT Highest rate 172 135 138 95 157 173 101 73 State/territory 100 93 99 74 109 113 62 60 Lowest rate 61 53 36 49 72 39 42 No. admissions 5,867 4,160 3,477 1,005 2,028 480 101 165 180 170 160 Wollondilly Serpentine - Jarrahdale Hobart - North East 1 140 Campaspe Kenmore - Brookمحeld - Moggill 130 120 110 100 90 96 Australian rate Mid North Palmerston 80 Tuggeranong 70 North East 60 40 30 Strathمحeld - Burwood - Ashمحeld Dandenong and Snowy Mountains and Auburn Far North Outback - North and East Kimberley North Canberra Alice Springs For this item, local area refers to an ABS standard geographic region known as a Statistical Area Level 3 (SA3) The size of each circle represents the number of admissions in each local area 6 100 1 200 Notes: Rates are standardised based on the age structure of the Australian population in 2001. State/territory and national rates are based on the total number of admissions and people in the geographic area. Sources: National Health Performance Authority analysis of Admitted Patient Care National Minimum Data Sets from 2010 11 to 2012 13 126 Australian Commission on Safety and Quality in Health Care
Figure 40: Estimated annual number of lumbar spine surgery admissions to hospital per 100,000 people aged, age standardised, by local area, remoteness and socioeconomic status (), 2010 11 to 2012 13 Remoteness Major cities Inner regional Outer regional Remote quintiles 1 2 3 4 5 1 2 3 4+ 1 2 3+ 1 2+ Average rate Low 90 High Low 104 104 Higher Low Higher 115 89 85 Low 49 Higher 75 180 170 160 1 140 130 120 115 110 100 90 80 96 Australian rate 90 104 104 89 85 75 70 60 40 49 30 For this item, local area refers to an ABS standard geographic region known as a Statistical Area Level 3 (SA3) The size of each circle represents the number of admissions in each local area 6 100 1 200 Notes: Rates are standardised based on the age structure of the Australian population in 2001. The national rate is based on the total number of admissions and people in Australia. Average rates are based on the total number of admissions and people in the local areas within each group. Sources: National Health Performance Authority analysis of Admitted Patient Care National Minimum Data Sets from 2010 11 to 2012 13 Australian Atlas of Healthcare Variation Surgical interventions 127
Lumbar spine surgery hospital admissions Resources North American Spine Society. Evidence-Based Clinical Guidelines for Multidisciplinary Spine Care Diagnosis and Treatment of Degenerative Lumbar Spinal Stenosis. 2011. Available at: www.spine.org/documents/ ResearchClinicalCare/Guidelines/ LumbarStenosis.pdf. North American Spine Society. Evidence-Based Clinical Guidelines for Multidisciplinary Spine Care Diagnosis and Treatment of Lumbar Disc Herniation with Radiculopathy. 2012. Available at: www.spine.org/portals/0/ Documents/ResearchClinicalCare/Guidelines/ LumbarDiscHerniation.pdf. North American Spine Society. Evidence-based Clinical Guidelines for Multidisciplinary Spine Care Diagnosis and Treatment of Degenerative Lumbar Spondylolisthesis. 2014. Available at: www.spine.org/ Documents/ResearchClinicalCare/Guidelines/ Spondylolisthesis.pdf. 1 Australian Institute of Health and Welfare. What role do hospitals play in treating back problems? 2015. (Accessed 6 October 2015 at: www.aihw.gov.au/back-problems/treatment-by-hospitals/). 2 Gibson JN, Grant IC, Waddell G. The Cochrane review of surgery for lumbar disc prolapse and degenerative lumbar spondylosis. Spine 24.17. 1999;1820 32. 3 Harris IA, Dao ATT. Trends of spinal fusion surgery in Australia: 1997 to 2006. ANZJS. 2009;79(11):783 8. 4 Shiri R, Karppinen J, Leino-Arjas P, Solovieva S, Viikari-Juntura E. The association between obesity and low back pain: a meta-analysis. AJE. 2010;171(2):135 54. 128 Australian Commission on Safety and Quality in Health Care