Clinical Trial: Outcome of Surgery for Sciatica - a Comparison of Data From Three National Quality Registries

Study Status: Completed
Recruit Status: Completed
Study Type: Observational [Patient Registry]

Official Title: Outcome of Surgery for Sciatica - a Comparison of Data From Three National Quality Registries

Brief Summary:

Purpose: The incidence of surgery for lumbar disc hernia varies. According to the national spine registries in Sweden, Norway and Denmark, there is a 30-60% difference in surgical incidence between these countries. The cause for this difference is not known. It may reflect a difference in incidence of lumbar disc hernia, but with a similar socio-economic and ethnical background in these countries, it is more likely that the differences are due to varying surgical indications. Comparing indications for surgery, patient reported outcome and factors predictive for outcome after surgery for lumbar disc hernia in these countries could provide information about optimal indications for surgery.

Hypotheses: (i) there are no differences in patient-reported outcome after surgery between these countries, (ii) there are no differences in indications for surgery between these countries and (iii), factors that predict outcome are similar in these countries.

Method of research: By using data from three Nordic national spine registers, we will compare baseline data, indications for surgery and patient reported outcome one year after surgery for lumbar disc herniation. Register based studies have advantages such as large sample sizes, reflecting real life, but they also have limitations such as lower follow-up rates than clinical trials. A non-response analysis will be performed to take this into account.

Detailed Summary:

This is an observational register based study, with prospective data registration and a retrospective study design. Included are individuals treated surgically for a lumbar disc herniation between the ages of 18 through 65 years, without a history of previous lumbar spine surgery. Surgery has been performed in Denmark, Norway or Sweden during 2011, 2012 or 2013. Data will be presented according to the STROBE criteria.

The registers

All registries have the aim of studying outcome after spine surgery. All departments and patients participate voluntarily. At the time of admission, the patient reports data consisting of information on social factors, comorbidity and previous surgery. After surgery, the surgeon records diagnosis and type of surgery performed.

The Swespine Register has included individuals treated with surgery for lumbar disc herniation since 1993. During the last decade, the number of departments participating in the registry has varied between 35 and 41 of the 42 to 45 departments providing spinal surgery services in Sweden. Coverage is approximately 90%. The completeness (number of patients reported to Swespine at the time of surgery) is approximately 80%.

The Norwegian Spine register, NORspine, is based on experiences from the Swespine register and previous validation studies from a local clinical registry, and was founded in 2007. In total 36 of 40 centers performing lumbar spine surgery in Norway report to NORspine. Coverage is approximately 90%. The completeness is approximately 65%.

The Danish spine register, DaneSpine, is based on Swespine and was acquired by the Danish Spine Society from the Swedish Society of Spinal Surgeons in 2009 and has successively
Sponsor: Karolinska Institutet

Current Primary Outcome: Oswestry disability index [ Time Frame: preoperative and 1 year postoperative ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• Numerical rating scale for leg pain [ Time Frame: preoperative and 1 year postoperative ]

  Index at baseline, index change from preoperative to 1 year follow-up and actual index at 1 year follow-up.

  Numerical rating scale for leg pain (from 0; no pain to 10; maximum pain). The numerical rating scale is used in Norway. The visual analogue scale (0-100) used in Sweden and Denmark will be converted to the numerical rating scale.

• Numerical rating scale for back pain [ Time Frame: preoperative and 1 year postoperative ]

  Index at baseline, index change from preoperative to 1 year follow-up and actual index at 1 year follow-up.

  Numerical rating scale for back pain (from 0; no pain to 10; maximum pain). The numerical rating scale is used in Norway. The visual analogue scale (0-100) used in Sweden and Denmark will be converted to the numerical rating scale.

• EQ-5D [ Time Frame: preoperative and 1 year postoperative ]

  EQ-5D is a 5-item questionnaire measuring mobility, self-care, usual activities, pain/discomfort and anxiety/depression. The answers are translated to an index representing the societal perspective of health. Index at baseline, change from preoperative to 1 year follow-up and actual index at 1 year follow-up will be presented.

  The EQ-5D-index is constructed using the British tariff (UK-TTO; from -0.59; worst possible health to 1; perfect health).

• Return to work rate [ Time Frame: Preoperative work rate. Work rate at the 1 year follow-up. ]
  The participants are asked to what extent they work preoperatively and at the 1 year follow-up.
• Additional surgery in the same segment of the lumbar spine [ Time Frame: During the 1 year follow-up ]

Original Secondary Outcome: Same as current

Information By: Karolinska Institutet

Dates:
Date Received: August 18, 2016
Date Started: January 2011
Date Completion:
Last Updated: August 30, 2016
Last Verified: August 2016