2024

• Huybregts, Jeroen G.J.; Polak, Samuel B.; Jacobs, Wilco C.; Arts, Mark P.; Meyer, Bernhard; Wostrack, Maria. (2024) Surgical versus conservative treatment for odontoid fractures in older people: an international prospective comparative study. Age and Ageing
  Academic article
• Danielsen, Elisabet; Ingebrigtsen, Tor; Gulati, Sasha; Salvesen, Øyvind Olav; Johansen, Tonje Okkenhaug; Nygaard, Øystein Petter. (2024) Patient Characteristics Associated with Worsening of Neck Pain-Related Disability after Surgery for Degenerative Cervical Myelopathy: A Nationwide Study of 1508 Patients. Neurosurgery
  Academic article

2023

• Holmberg, Siril T.; Skurtveit, Svetlana; Gulati, Sasha; Salvesen, Øyvind; Nygaard, Øystein P.; Solberg, Tore K.. (2023) Persistent Use of Prescription Opioids Before and After Lumbar Spine Surgery: Observational Study With Prospectively Collected Data From Two Norwegian National Registries. Spine
  Academic article
• Mikkelsen, Eirik; Ingebrigtsen, Tor; Thyrhaug, Anette Moltu; Olsen, Lena Ringstad; Nygaard, Øystein Petter; Austevoll, Ivar Magne. (2023) The Norwegian registry for spine surgery (NORspine): cohort profile. European spine journal
  Academic article
• Riksaasen, Anniken; Kaur, Simran; Solberg, Tore; Austevoll, Ivar Magne; Brox, Jens Ivar; Dolatowski, Filip Celestyn. (2023) Impact of the number of previous lumbar operations on patient-reported outcomes after surgery for lumbar spinal stenosis or lumbar disc herniation. The Bone & Joint Journal
  Academic article
• Lønne, Vetle Vangen; Hara, Sozaburo; Gulati, Sasha; Aasdahl, Lene; Salvesen, Øyvind Olav; Nygaard, Øystein Petter. (2023) Return to work after surgery for degenerative cervical myelopathy: a nationwide registry-based observational study. Acta Neurochirurgica
  Academic article
• Danielsen, Elisabet; Gulati, Sasha; Salvesen, Øyvind Olav; Ingebrigtsen, Tor; Nygaard, Øystein Petter; Solberg, Tore. (2023) Clinical outcomes after surgery for cervical radiculopathy performed in public and private hospitals : a nationwide relative effectiveness study. The Bone & Joint Journal
  Academic article
• Hammer, Lovise; Ingebrigtsen, Tor; Gulati, Sasha; Hara, Sozaburo; Nygaard, Øystein Petter; Hara, Karen Walseth. (2023) Prospects of returning to work after lumbar spine surgery for patients considering disability pension: A nationwide study based on data from the Norwegian Registry for Spine Surgery. Occupational and Environmental Medicine
  Academic article
• Johansen, Tonje Okkenhaug; Holmberg, Siril Therese; Danielsen, Elisabet; Rao, Vidar; Salvesen, Øyvind Olav; Andresen, Hege. (2023) Long-Term Results After Surgery for Degenerative Cervical Myelopathy. Neurosurgery
  Academic article

2022

• Lie, Marie; Pedersen, Linda Margareth; Heuch, Ingrid; Winsvold, Bendik K S; Gjerstad, Johannes; Hasvik, Eivind Olay. (2022) Low Back Pain With Persistent Radiculopathy; the Clinical Role of Genetic Variants in the Genes SOX5, CCDC26/GSDMC and DCC. Frontiers in Genetics
  Academic article
• Ingebrigtsen, Tor; Aune, Grethe; Karlsen, Martine Eriksen; Gulati, Sasha; Kolstad, Frode; Nygaard, Øystein Petter. (2022) Non-respondents do not bias outcome assessment after cervical spine surgery: a multicenter observational study from the Norwegian registry for spine surgery (NORspine). Acta Neurochirurgica
  Academic article
• Holmberg, Siril Therese; Gulati, Agnete Malm; Johansen, Tonje Okkenhaug; Salvesen, Øyvind; Vangen-Lønne, Vetle; Solberg, Tore. (2022) Surgery for degenerative cervical myelopathy in patients with rheumatoid arthritis and ankylosing spondylitis: a nationwide registry-based study with patient-reported outcomes. Acta Neurochirurgica
  Academic article
• Johansen, Tonje Okkenhaug; Vangen-Lønne, Vetle; Holmberg, Siril Therese; Salvesen, Øyvind; Solberg, Tore; Gulati, Agnete Malm. (2022) Surgery for degenerative cervical myelopathy in the elderly: a nationwide registry-based observational study with patient-reported outcomes. Acta Neurochirurgica
  Academic article
• Hara, Sozaburo; Andresen, Hege; Solheim, Ole; Carlsen, Sven Magnus; Sundstrøm, Terje; Lønne, Greger. (2022) Effect of Spinal Cord Burst Stimulation vs Placebo Stimulation on Disability in Patients With Chronic Radicular Pain After Lumbar Spine Surgery: A Randomized Clinical Trial. Journal of the American Medical Association (JAMA)
  Academic article
• Lønne, Vetle Vangen; Madsbu, Mattis Aleksander; Salvesen, Øyvind Olav; Nygaard, Øystein Petter; Solberg, Tore; Gulati, Sasha. (2022) Is surgery for recurrent lumbar disc herniation worthwhile or futile? A single center observational study with patient reported outcomes. Brain and Spine
  Academic article
• Danielsen, Elisabeth; Mjåset, Christer; Ingebrigtsen, Tor; Gulati, Sasha; Grotle, Margreth; Rudolfsen, Jan Håkon. (2022) A nationwide study of patients operated for cervical degenerative disorders in public and private hospitals. Scientific Reports
  Academic article

2021

• Johansen, Tonje Okkenhaug; Sundseth, Jarle Østberg; Fredriksli, Oddrun; Andresen, Hege; Zwart, John-Anker; Kolstad, Frode. (2021) Effect of Arthroplasty vs Fusion for Patients With Cervical Radiculopathy: A Randomized Clinical Trial. JAMA Network Open
  Academic article
• Werner, David Andreas Thomas; Grotle, Margreth; Småstuen, Milada Cvancarova; Gulati, Sasha; Nygaard, Øystein Petter; Salvesen, Øyvind. (2021) A prognostic model for failure and worsening after lumbar microdiscectomy: a multicenter study from the Norwegian Registry for Spine Surgery. Acta Neurochirurgica
  Academic article
• Holmberg, Siril Therese; Fredheim, Olav Magnus; Skurtveit, Svetlana Ondrasova; Salvesen, Øyvind; Nygaard, Øystein Petter; Gulati, Agnete Malm. (2021) Persistent Use of Prescription Opioids Following Lumbar Spine Surgery: Observational Study with Prospectively Collected Data from Two Norwegian Nationwide Registries. Spine
  Academic article
• Weber, Clemens; Myrseth, Erling; Kurz, Kathinka Dæhli; Frič, Radek; Ingebrigtsen, Tor; Helseth, Eirik. (2021) MR av nakke i vektbærende stilling?. Tidsskrift for Den norske legeforening
  Short communication
• Gulati, Sasha; Vangen-Lønne, Vetle; Nygaard, Øystein P; Gulati, Agnete M; Hammer, Tommy A; Johansen, Tonje O. (2021) Surgery for degenerative cervical myelopathy: A nationwide registry-based observational study with patient-reported outcomes. Neurosurgery
  Academic article
• Holmberg, Siril Therese; Vangen-Lønne, Vetle; Gulati, Agnete Malm; Nygaard, Øystein P; Solberg, Tore K.; Salvesen, Øyvind. (2021) Pain During Sex Before and After Decompressive Surgery for Lumbar Spinal Stenosis: A Multicenter Observational Study. Spine
  Academic article
• Shrestha, Dipak; Shrestha, Rohit; Grotle, Margreth; Nygaard, Øystein Petter; Solberg, Tore. (2021) Validation of the Nepali versions of the Neck Disability Index and the Numerical Rating Scale for Neck Pain. Spine
  Academic article

2020

• Holmberg, Siril Therese; Salvesen, Øyvind; Vangen-Lønne, Vetle; Hara, Sozaburo; Fredheim, Olav Magnus; Solberg, Tore. (2020) Pain During Sex Before and After Surgery for Lumbar Disc Herniation - A Multicenter Observational Study. Spine
  Academic article
• Bråten, Lars Christian Haugli; Grøvle, Lars; Espeland, Ansgar; Pripp, Are Hugo; Grotle, Margreth; Hellum, Christian. (2020) Clinical effect modifiers of antibiotic treatment in patients with chronic low back pain and Modic changes - Secondary analyses of a randomised, placebo-controlled trial (the AIM study). BMC Musculoskeletal Disorders
  Academic article
• Madsbu, Mattis Aleksander; Salvesen, Øyvind; Carlsen, Sven Magnus; Westin, Steinar; Onarheim, Kristian; Nygaard, Øystein Petter. (2020) Surgery for herniated lumbar disc in private vs public hospitals: A pragmatic comparative effectiveness study. Acta Neurochirurgica
  Academic article
• Vangen-Lønne, Vetle; Madsbu, Mattis Aleksander; Salvesen, Øyvind; Nygaard, Øystein Petter; Solberg, Tore; Gulati, Sasha. (2020) Microdiscectomy for Lumbar Disc Herniation: A Single-Center Observational Study. World Neurosurgery
  Academic article
• Polak, Samuel B.; Madsbu, Mattis Aleksander; Vangen-Lønne, Vetle; Salvesen, Øyvind; Nygaard, Øystein Petter; Solberg, Tore. (2020) Surgery for Extraforaminal Lumbar Disc Herniation: A Single Center Comparative Observational Study. Acta Neurochirurgica
  Academic article

2019

• Bråten, Lars Christian Haugli; Rolfsen, Mads Peder; Espeland, Ansgar; Wigemyr, Monica; Assmus, Jörg; Froholdt, Anne . (2019) Efficacy of antibiotic treatment in patients with chronic low back pain and Modic changes (the AIM study): double blind, randomised, placebo controlled, multicentre trial. The BMJ
  Academic article

2018

• Giri, Samita; Risnes, Kari Ravndal; Uleberg, Oddvar; Rogne, Tormod; Shrestha, Sanu Krishna; Nygaard, Øystein Petter. (2018) Impact of 2015 Earthquakes on a local hospital in Nepal: A Prospective Hospital-based Study. PLOS ONE
  Academic article
• Madsbu, Mattis Aleksander; Salvesen, Øyvind; Werner, David Andreas Thomas; Franssen, Eric; Weber, Clemens; Nygaard, Øystein Petter. (2018) Surgery for Herniated Lumbar Disc in Daily Tobacco Smokers: A Multicenter Observational Study. World Neurosurgery
  Academic article

2017

• Gulati, Sasha; Madsbu, Mattis Aleksander; Solberg, Tore; Sørlie, Andreas; Giannadakis, Charalampis; Skram, Marius Kurås. (2017) Lumbar microdiscectomy for sciatica in adolescents: a multicentre observational registry-based study. Acta Neurochirurgica
  Academic article
• Madsbu, Mattis Aleksander; Solberg, Tore; Salvesen, Øyvind; Nygaard, Øystein Petter; Gulati, Sasha. (2017) Surgery for herniated lumbar disk in individuals 65 years of age or older: A multicenter observational study. JAMA Surgery
  Academic article
• Werner, David Andreas Thomas; Grotle, Margreth; Gulati, Sasha; Austevoll, Ivar Magne; Lønne, Greger; Nygaard, Øystein Petter. (2017) Criteria for failure and worsening after surgery for lumbar disc herniation: a multicenter observational study based on data from the Norwegian Registry for Spine Surgery. European spine journal
  Academic article
• Lønne, Greger; Schoenfeld, Andrew J.; Cha, Thomas D.; Nygaard, Øystein Petter; Zwart, John-Anker; Solberg, Tore. (2017) Variation in selection criteria and approaches to surgery for Lumbar Spinal Stenosis among patients treated in Boston and Norway. Clinical neurology and neurosurgery (Dutch-Flemish ed. Print)
  Academic article
• Habiba, Samer; Nygaard, Øystein Petter; Brox, Jens Ivar; Hellum, Christian; Austevoll, Ivar Magne; Solberg, Tore. (2017) Risk factors for surgical site infections among 1,772 patients operated on for lumbar disc herniation: a multicentre observational registry-based study. Acta Neurochirurgica
  Academic article
• Weber, Clemens; Lønne, Greger; Rao, Vidar; Jakola, Asgeir Store; Solheim, Ole; Nerland, Ulf Skule. (2017) Surgical management of lumbar spinal stenosis: a survey among Norwegian spine surgeons. Acta Neurochirurgica
  Academic article
• Madsbu, Mattis Aleksander; Øie, Lise Rystad; Salvesen, Øyvind; Vangen-Lønne, Vetle; Nygaard, Øystein Petter; Solberg, Tore. (2017) Lumbar microdiscectomy in obese patients: a multicenter observational study. World Neurosurgery
  Academic article
• Storheim, Kjersti; Espeland, Ansgar; Grøvle, Lars; Skouen, Jan Sture; Assmus, Jörg; Anke, Audny. (2017) Antibiotic treatment In patients with chronic low back pain and Modic changes (the AIM study): study protocol for a randomised controlled trial. Trials
  Academic article

2016

• Weber, Clemens; Giannadakis, Charalampis; Rao, Vidar; Jakola, Asgeir Store; Nerland, Ulf Skule; Nygaard, Øystein Petter. (2016) Is there an association between radiological severity of lumbar spinal stenosis and disability, pain, or surgical outcome? A multicenter observational study. Spine
  Academic article
• Weber, Clemens; Kvistad, Kjell Arne; Moholdt, Viggo; Nygaard, Øystein Petter; Solheim, Ole. (2016) Repeated 3.0 tesla magnetic resonance imaging after clinically successful lumbar disc surgery. Spine
  Academic article
• Gulati, Agnete Malm; Solberg, Tore; Giannadakis, Charalampis; Hoff, Mari; Haugeberg, Glenn; Nygaard, Øystein Petter. (2016) Surgery for lumbar spinal stenosis in patients with rheumatoid arthritis: A multicenter observational study. European Journal of Rheumatology
  Academic article
• Sørlie, Andreas; Gulati, Sasha; Giannadakis, Charalampis; Carlsen, Sven Magnus; Salvesen, Øyvind; Nygaard, Øystein Petter. (2016) Open discectomy vs microdiscectomy for lumbar disc herniation - a protocol for a pragmatic comparative effectiveness study. F1000 Research
  Academic article
• Sundseth, Jarle Østberg; Fredriksli, Oddrun; Kolstad, Frode; Johnsen, Lars Gunnar; Pripp, Are Hugo; Andresen, Hege. (2016) The Norwegian Cervical Arthroplasty Trial (NORCAT): 2-year clinical outcome after single-level cervical arthroplasty versus fusion—a prospective, single-blinded, randomized, controlled multicenter study. European spine journal
  Academic article
• Giannadakis, Charalampis; Solheim, Ole Skeidsvoll; Jakola, Asgeir Store; Nordseth, Trond; Gulati, Agnete Malm; Nerland, Ulf Skule. (2016) Surgery for lumbar spinal stenosis in individuals aged 80 and older: a multicenter observational study. Journal of The American Geriatrics Society
  Academic article
• Kristiansen, Jon-André; Balteskard, Lise; Slettebø, Haldor; Nygaard, Øystein Petter; Lied, Bjarne Lidvar; Kolstad, Frode. (2016) The use of surgery for cervical degenerative disease in Norway in the period 2008–2014: A population-based study of 6511 procedures. Acta Neurochirurgica
  Academic article
• Sundseth, Jarle Østberg; Jacobsen, Eva Astrid; Kolstad, Frode; Sletteberg, Ruth; Nygaard, Øystein Petter; Johnsen, Lars Gunnar. (2016) Heterotopic ossification and clinical outcome in nonconstrained cervical arthroplasty 2 years after surgery: the Norwegian Cervical Arthroplasty Trial (NORCAT). European spine journal
  Academic article

2015

• Sundseth, Jarle Østberg; Kolstad, Frode; Johnsen, Lars Gunnar; Pripp, Are Hugo; Nygaard, Øystein Petter; Andresen, Hege. (2015) The Neck Disability Index (NDI) and its correlation with quality of life and mental health measures among patients with single-level cervical disc disease scheduled for surgery. Acta Neurochirurgica
  Academic article
• Nerland, Ulf Skule; Jakola, Asgeir Store; Giannadakis, Charalampis; Solheim, Ole; Weber, Clemens; Nygaard, Øystein Petter. (2015) The risk of getting worse: predictors of deterioration after decompressive surgery for lumbar spinal stenosis: a multicenter observational study. World Neurosurgery
  Academic article
• Giannadakis, Charalampis; Nerland, Ulf Skule; Solheim, Ole; Jakola, Asgeir Store; Gulati, Michel; Weber, Clemens. (2015) Does obesity affect outcomes after decompressive surgery for lumbar spinal stenosis? – A multicenter observational registry-based study. World Neurosurgery
  Academic article
• Gulati, Sasha; Nordseth, Trond; Nerland, Ulf Skule; Gulati, Michel; Weber, Clemens; Giannadakis, Charalampis. (2015) Does daily tobacco smoking affect outcomes after microdecompression for degenerative central lumbar spinal stenosis? – A multicenter observational registry-based study. Acta Neurochirurgica
  Academic article
• Giannadakis, Charalampis; Hammersbøen, Lars Egil; Feyling, Casper; Solheim, Ole; Jakola, Asgeir Store; Nerland, Ulf Skule. (2015) Microsurgical decompression for central lumbar spinal stenosis: a single-center observational study. Acta Neurochirurgica
  Academic article
• Weber, Clemens; Rao, Vidar; Gulati, Sasha; Kvistad, Kjell Arne; Nygaard, Øystein Petter; Lønne, Greger. (2015) Inter-and Intraobserver Agreement of Morphological Grading for Central Lumbar Spinal Stenosis on Magnetic Resonance Imaging. Global Spine Journal (GSJ)
  Academic article
• Lønne, Greger; Johnsen, Lars Gunnar; Aas, Eline; Lydersen, Stian; Andresen, Hege; Rønning, Roar Eng. (2015) Comparing Cost-effectiveness of X-Stop with Minimally Invasive Decompression in Lumbar Spinal Stenosis: A Randomized Controlled Trial. Spine
  Academic article
• Lønne, Greger; Johnsen, Lars Gunnar; Rossvoll, Ivar; Andresen, Hege; Storheim, Kjersti; Zwart, John-Anker. (2015) Minimally invasive decompression versus x-stop in lumbar spinal stenosis: A randomized controlled multicenter study. Spine
  Academic article
• Nerland, Ulf Skule; Jakola, Asgeir Store; Solheim, Ole; Weber, Clemens; Rao, Vidar; Lønne, Greger. (2015) Minimally invasive decompression versus open laminectomy for central stenosis of the lumbar spine: pragmatic comparative effectiveness study. The BMJ
  Academic article

2014

• Nygaard, Øystein Petter; Kolstad, F. (2014) Spinalkanalens degenerative sykdommer. Forlaget Vett & Viten AS
  Chapter
• Nerland, Ulf Skule; Jakola, Asgeir Store; Solheim, Ole; Weber, Clemens; Rao, Vidar; Lønne, Greger. (2014) Comparative effectiveness of microdecompression and laminectomy for central lumbar spinal stenosis: Study protocol for an observational study. BMJ Open
  Academic article
• Weber, Clemens; Gulati, Sasha; Jakola, Asgeir Store; Habiba, Samer; Nygaard, Øystein Petter; Johannesen, Tom Børge. (2014) Incidence rates and surgery of primary intraspinal tumors in the era of modern neuroimaging: A national population-based study. Spine
  Academic article
• Johnsen, Lars Gunnar; Hellum, Christian; Storheim, Kjersti; Nygaard, Øystein Petter; Brox, Jens Ivar; Rossvoll, Ivar. (2014) Cost-effectiveness of total disc replacement versus multidisciplinary rehabilitation in patients with chronic low back pain: A norwegian multicenter RCT. Spine
  Academic article
• Lønne, Greger; Ødegård, Bent; Johnsen, Lars Gunnar; Solberg, Tore; Kvistad, Kjell Arne; Nygaard, Øystein Petter. (2014) MRI evaluation of lumbar spinal stenosis: Is a rapid visual assessment as good as area measurement?. European spine journal
  Academic article

2013

• Weber, Clemens; Jakola, Asgeir S; Gulati, Sasha; Nygaard, Øystein Petter; Solheim, Ole. (2013) Evidence-based clinical management and utilization of new technology in European neurosurgery. Acta Neurochirurgica
  Academic article
• Solberg, Tore; Johnsen, Lars Gunnar; Nygaard, Øystein Petter; Grotle, Margreth. (2013) Can we define success criteria for lumbar disc surgery? Estimates for a substantial amount of improvement in core outcome measures. Acta Orthopaedica
  Academic article
• Sundseth, Jarle; Jacobsen, Eva Astrid; Kolstad, Frode; Nygaard, Øystein Petter; Zwart, John-Anker; Hol, Per Kristian. (2013) Magnetic resonance imaging evaluation after implantation of a titanium cervical disc prosthesis: a comparison of 1.5 and 3 Tesla magnet strength. European spine journal
  Academic article
• Iversen, Trond; Solberg, Tore; Romner, Bertil; Wilsgaard, Tom; Nygaard, Øystein Petter; Waterloo, Knut . (2013) Accuracy of physical examination for chronic lumbar radiculopathy. BMC Musculoskeletal Disorders
  Academic article
• Johnsen, Lars Gunnar; Hellum, Christian; Nygaard, Øystein Petter; Storheim, Kjersti; Brox, Jens Ivar; Rossvoll, Ivar. (2013) Comparison of the SF6D, the EQ5D, and the oswestry disability index in patients with chronic low back pain and degenerative disc disease. BMC Musculoskeletal Disorders
  Academic article

2012

• Gulati, Sasha; Jakola, Asgeir S; Solheim, Ole; Gabrielsen, Sindre; Godø, Pål Anders; Skogstad, Bjørn. (2012) Assessment of referrals to a multidisciplinary outpatient clinic for patients with back pain. Journal of Manual & Manipulative Therapy
  Academic article
• Gulati, Sasha; Jakola, Asgeir S; Solheim, Ole; Godø, Pål A; Gabrielsen, Sindre; Skogstad, Bjørn. (2012) Kvalitetsevaluering av henvisninger mottatt ved en tverrfaglig ryggpoliklinikk. Muskel & skjelett
  Article in business/trade/industry journal
• Sørlie, Andreas; Moholdt, Viggo; Kvistad, Kjell Arne; Nygaard, Øystein Petter; Ingebrigtsen, Tor; Iversen, Trond. (2012) Modic type I changes and recovery of back pain after lumbar microdiscectomy. European spine journal
  Academic article
• Lønne, Greger; Solberg, Tore; Sjåvik, Kristin; Nygaard, Øystein Petter. (2012) Recovery of muscle strength after microdiscectomy for lumbar disc herniation: a prospective cohort study with 1-year follow-up. European spine journal
  Academic article
• Lennarson, Peter; Boedeker, Ben H; Kuper, Gail M; Nygaard, Øystein Petter; Johansen, Tonje Okkenhaug; Halvorsen, Annette. (2012) Cover Utilization of a Civilian Academic Center as a Force Multiplier in Support of NATO Special Operations Medicine – A Pilot Demonstration. IOS Press
  Academic chapter/article/Conference paper

2011

• Hellum, Christian; Johnsen, Lars Gunnar; Storheim, Kjersti; Nygaard, Øystein Petter; Brox, Jens Ivar; Rossvoll, Ivar. (2011) Surgery with disc prosthesis versus rehabilitation in patients with lowback pain and degenerative disc: two year follow-up of randomised study. BMJ. British Medical Journal
  Academic article
• Solberg, Tore; Sørlie, Andreas; Sjåvik, Kristin; Nygaard, Øystein Petter; Ingebrigtsen, Tor. (2011) Would loss to follow-up bias the outcome evaluation of patients operated for degenerative disorders of the lumbar spine?. Acta Orthopaedica
  Academic article
• Myran, Rigmor; Hagen, Knut; Svebak, Sven; Nygaard, Øystein Petter; Zwart, John-Anker. (2011) Headache and musculoskeletal complaints among subjects with self reported whiplash injury. The HUNT-2 study. BMC Musculoskeletal Disorders
  Academic article
• Søndenaa, Erik; Nygaard, Øyvind; Nøttestad, Jim Aage; Linaker, Olav Morten. (2011) Validation and adaptation of the Norwegian version of Hayes Ability Screening Index for intellectual difficulties in a psychiatric sample. Nordic Journal of Psychiatry
  Academic article
• Iversen, Trond; Solberg, Tore; Romner, Bertil; Wilsgaard, Tom; Twisk, Jos WR; Anke, Audny. (2011) Effect of caudal epidural steroid or saline injection in chronic lumbar radiculopathy: multicentre, blinded, randomised controlled trial. BMJ. British Medical Journal
  Academic article
• Solheim, Ole; Unsgård, Geirmund; Nygaard, Øystein Petter. (2011) Ultrasound guided surgery in patients with intracranial tumours. NTNU
  Doctoral dissertation
• Kolstad, Frode; Leivseth, Gunnar; Nygaard, Øystein Petter. (2011) Cervical Disc Disease Biomechanical Aspects. NTNU
  Doctoral dissertation
• Myran, Rigmor; Zwart, John-Anker; Kvistad, Kjell Arne; Folvik, Mari; Lydersen, Stian; Rø, Magne. (2011) Clinical Characteristics, Pain, and Disability in Relation to Alar Ligament MRI Findings. Spine
  Academic article

2010

• Nygaard, Øystein Petter; Rø, Magne; Andersen, Tor Inge; Zwart, John-Anker. (2010) Nakkesmerter med og uten nerverotsaffeksjon :. Tidsskrift for Den norske legeforening
  Academic literature review
• Myran, Rigmor; Nygaard, Øystein Petter; Zwart, John-Anker; Kvistad, Kjell Arne. (2010) Post-traumatic neck pain. Epidemiological, neuroradiological and clinical aspects. NTNU-trykk
  Doctoral dissertation
• Jakola, Asgeir S; Sørlie, Andreas; Gulati, Sasha; Nygaard, Øystein Petter; Lydersen, Stian; Solberg, Tore. (2010) Clinical outcomes and safety assessment in elderly patients undergoing decompressive laminectomy for lumbar spinal stenosis: a prospective study. BMC Surgery
  Academic article
• Brox, Jens Ivar; Nygaard, Øystein Petter; Holm, Inger; Keller, Anne; Ingebrigtsen, Tor; Reikerås, Olav. (2010) Four-year follow-up of surgical versus non-surgical therapy for chronic low back pain. Annals of the Rheumatic Diseases
  Academic article
• Heuch, Ingrid; Hagen, Knut; Heuch, Ivar; Nygaard, Øystein Petter; Zwart, John-Anker. (2010) The impact of body mass index on the prevalence of low back pain. The HUNT study. Spine
  Academic article
• Kolstad, Frode; Nygaard, Øystein Petter; Andresen, Hege; Leivseth, Gunnar. (2010) Anterior Cervical Arthrodesis Using a "Stand Alone" Cylindrical Titanium Cage Prospective Analysis of Radiographic Parameters. Spine
  Academic article
• Brox, Jens Ivar; Nygaard, Øystein Petter; Keller, Anne; Ingebrigtsen, Tor; Reikerås, Olav; Holm, Inger. (2010) Four-year follow-up of surgical versus non-surgical therapy for chronic low back pain. Annals of the Rheumatic Diseases
  Academic article

2009

• Nygaard, Øystein P; Myran, Rigmor; Zwart, John-Anker; Kvistad, Kjell Arne; Rø, Magne; Andresen, Hege. (2009) Clinical characteristics and functional disability and relation to alar ligament MRI findings on MRI. Scnadinavian Neurosurgical Society
  Abstract
• Gabrielsen, S; Godø, Preben; Gulati, Sasha; Jakola, A; Skogstad, Bent Erik; Solheim, Ole. (2009) Kvalitetsevaluering av henvisninger mottatt ved Tverrfaglig ryggpoliklinikk, St. Olav Hospital. Norsk ortopedisk forenings høstmøte
  Abstract
• Hellum, Christian; Johnsen, Lars Gunnar; Storheim, K; Nygaard, Øystein P; Brox, Jens Ivar; Rossvoll, Ivar. (2009) Effect of total lumbar disc prsthesis versus multidisciplinary rehabilitation in patients with chronic low back pain and degenerative disc. 2-years results from a prospective randomized clinical multicenter trial. Eurospine
  Abstract
• Hellum, Christian; Johnsen, Lars Gunnar; Storheim, K; Nygaard, Øystein P; Brox, Jens Ivar; Rossvoll, Ivar. (2009) Sammenligning av operasjon med skiveprotese og tverrfaglig ryggrehabilitering ved langvarige korsryggsmerter med degenerative skiveforandringer, 2 års resultater. en prospektiv randomisert multisenterstudie. Norsk ortopedisk forenings høstmøte
  Abstract
• Jakola, A; Sørlie, A; Gulati, Sasha; Lydersen, Stian; Nygaard, Øystein P; Solberg, T. (2009) Ett års resultater etter konvensjonel laminektomi hos pasienter over 70 år. Norsk ortopedisk forenings høstmøte
  Abstract
• Austevoll, N; Brox, Jens Ivar; Helse, Habiba S; Hellum, Christian; Ingebrigtsen, T; Nygaard, Øystein P. (2009) Nasjonalt kvalitetsregister for Ryggkirurgi - Presentasjon av ny versjon. Norsk ortopedisk forenings høstmøte
  Abstract
• Brox, Jens Ivar; Nygaard, Øystein P.; Holm, Inger; Keller, Anne; Ingebrigtsen, T; Reikerås, Olav. (2009) Four-year follow-up of surgical versus non-surgical therapy for chronic low back pain. Annals of the Rheumatic Diseases
  Academic article

2008

• Solheim, Ole; Moholdt, Viggo; Kvistad, Kjell Arne; Nygaard, Øystein P. (2008) Tolkning av tidlig postoperativ MR etter lumbal prolapskirurgi. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Sundseth, J; Bliksås, Andreas; Kolstad, Frode; Lied, B.; Zwart, John-Anker; Myrseth, E. . (2008) Behandling av cervikal radikulopati med fremre diskektomi og innsetting av skiveprotese eller bur (CAGE). Kliniske, billedmessige og biomekansike aspekter. En nasjonal randomisert multisenter studie. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Nygaard, Øystein P; Solheim, Ole; Müller, Tom B.. (2008) MAPN (microscopic assisted percutaneous nucleotomy)et alternativ til mikrodiskektomi?. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Sørlie, A; Solberg, T; Skau, Philip; Nygaard, Øystein P; Brox, Jens Ivar; Hellum, Christian. (2008) Nasjonalt kvalitetsregister for ryggkirurgi - gjennomgang. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Solheim, Ole; Nygaard, Øystein P. (2008) Lumbar Epidural Hematoma after Chiropractic Manipulation for Lower-back Pain: Case Report. Neurosurgery
  Letter to the editor
• Myran, Rigmor; Kvistad, Kjell Arne; Nygaard, Øystein P; Nygaard, OP; Andresen, H; Folvik, M. (2008) Magnetic resonance imaging assessment of the alar ligaments in whiplash injuries - A case-control study. Spine
  Academic article

2007

• Solheim, Ole; Nygaard, Øystein P. (2007) Minimal invasive kirurgi for lumbal spinal stenose - erfaringer og tidlige resultater. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Myran, Rigmor; Kvistad, Kjell Arne; Folvik, M.; Nygaard, Øystein P; Zwart, John-Anker. (2007) MR undersøkelse av alar ligamenter etter whiplash. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Myran, Rigmor; Kvistad, Kjell Arne; Andresen, Hege; Folvik, M.; Zwart, John-Anker; Nygaard, Øystein P. (2007) MR diagnostikk av alarligamentere etter whiplash. Nakkesleng og cervikobrachialgi. Tverrfaglige seminarer i Tønsberg: Rapport
  Abstract
• Nygaard, Øystein P; Lønne, Greger; Husby, P; Grundnes, O; Rossvoll, Ivar; Johnsen, Lars Gunnar. (2007) Sammenligning av to kirurgiske metoder for behandling av sentral spinal stenose. Presentasjon av protokollen for en nasjonal multisenterstudie. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Sørlie, A; Solberg, T; Skau, Philip; Nygaard, Øystein P; Brox, Jens Ivar; Hellum, Christian. (2007) Nasjonalt kvalitetsregister for ryggkirurgi - status og utfordringer. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Solheim, Ole; Jørgensen, Jan Valentin; Nygaard, Øystein P. (2007) Lumbar Epidural Hematoma after Chiropractic Manipulation for Lower-back Pain: Case Report. Neurosurgery
  Academic article
• Hamouda, Hazem; Witsø, Eivind; Moghani, Nedal; Shahwan, Ahmed; Nygaard, Øystein P. (2007) Soft tissue infection after missile injuries to the extremities- a non-randomized, prospective study in Gaza City. Prehospital and Disaster Medicine
  Academic article
• Nygaard, Øystein P; Kolstad, Frode. (2007) Spinalkanalens degenerative sykdommer. Forlaget Vett & Viten AS
  Academic chapter/article/Conference paper

2006

• Ingebrigtsen, Tom; Solberg, Tore; Skau, Philip; Nygaard, Øystein P; Brox, Jens Ivar; Hellum, Christian. (2006) Nasjonalt kvalitetsregister for ryggkirurgi, bakgrunn og fremdrift. Vitenskapelige forhandlinger - De norske kirurgiske foreninger
  Abstract
• Brox, Jens Ivar; Reikeras, Olav; Reikerås, Olav; Nygaard, Øystein; Nygaard, Øystein Petter; Sørensen, Roger. (2006) Lumbar instrumented fusion compared with cognitive intervention and exercises in patients with chronic back pain after previous surgery for disc herniation: A prospective randomized controlled study. Pain
  Academic article
• Kolstad, Frode; Rygh, Ola; Selbekk, Tormod; Unsgård, Geirmund; Nygaard, Øystein P. (2006) Three-dimensional ultrasonography navigation in spinal cord tumor surgery - Technical note. Journal of Neurosurgery : Spine
  Academic article
• Leivseth, Gunnar; Kolstad, Frode; Nygaard, Øystein P; Zoega, B; Frobin, Wolfgang; Brinckmann, Paul. (2006) Comparing precision of distortion-compensated and stereophotogrammetric Roentgen analysis when monitoring fusion in the cervical spine. European spine journal
  Academic article

2005

• Kolstad, Frode; Nygaard, Øystein P; Leivseth, Gunnar. (2005) Transforaminal steroid injections in the treatment of cervical radiculopathy. A prospective outcome study. Acta Neurochirurgica
  Academic article
• Kolstad, Frode; Myhr, G; Kvistad, Kjell Arne; Nygaard, Øystein P; Leivseth, Gunnar. (2005) Degeneration and height of cervical discs classified from MRI compared with precise height measurements from radiographs. European Journal of Radiology
  Academic article
• Nygaard, Øystein P.; Kolstad, Frode; Kvistad, Kjell Arne; Zwart, John-Anker; Solberg, Terje; Lied, Bjarne Lidvar. (2005) Kronisk nakkeslengsyndrom er ingen indikasjon for kraniocervikal fiksasjon. Tidsskrift for Den norske legeforening
  Academic article

2004

• Brox, Jens Ivar; Reikerås, Olav; Sørensen, Roger; Riise, Rolf Bjarne; Nygaard, Øystein Petter; Ingebrigtsen, Tor. (2004) Untitled - Response. Spine
  Reader opinion piece
• Brox, Jens Ivar; Reikerås, Olav; Sørensen, Roger; Riise, Rolf; Nygaard, Øystein P; Ingebrigtsen, Tor. (2004) Was the differnce in the Swedish study clinically significant?. Spine
  Letter to the editor
• Brox, Jens Ivar; Reikerås, Olav; Sørensen, Roger; Riise, Rolf; Nygaard, Øystein P; Ingebrigtsen, Tor. (2004) Power is important when a clinically relevant diffreence is not statistically significant. Spine
  Letter to the editor
• Brox, Jens Ivar; Reikerås, Olav; Sørensen, Roger; Riise, Rolf; Nygaard, Øystein P; Ingebrigtsen, Tor. (2004) The sample mean is the best indicator of the population value. Spine
  Letter to the editor
• Solberg, Tore K.; Nygaard, Øystein P; Sjaavik, Kristin; Hofoss, Dag; Ingebrigtsen, Tor. (2004) The risk of "getting worse" after lumbar microdiscectomy. European spine journal
  Academic article

2002

• Gårseth, Mari; Sonnewald, Ursula; White, Linda; rød, marianne; Nygaard, Øystein P; Zwart, John-Anker. (2002) Metabolic changes in the cerebrospinal fluid of patients with lumbar disc herniation or spinal stenosis. Journal of Neuroscience Research
  Academic article

2001

• Vik, Anne; Zwart, John-Anker; Hulleberg, Gunn; Nygaard, Øystein P. (2001) Eight year outcome after surgery for lumbar disc herniation: a comparison of reoperated and not reoperated patients. Acta Neurochirurgica
  Academic article

2000

• Gårseth, Mari; Sonnewald, Ursula; White, Linda; Rød, Marianne; Zwart, John-Anker; Nygaard, Øystein P. (2000) Proton magnetic resonance spectroscopy of cerebrospinal fluid in neurodegenerative disease: Indication of glial energy impairment in Huntington chorea, but not Parkinson disease. Journal of Neuroscience Research
  Academic article
• Vik, Anne; Hulleberg, Gunn; Zwart, John-Anker; Nygaard, Øystein P. (2000) Langtidsoppfølging etter operasjon av lumbal skiveprolaps. Tidsskrift for Den norske legeforening
  Academic article
• Nygaard, Øystein P; Kloster, Roar; Solberg, Tore. (2000) Duration of leg pain as a predictor of outcome after surgery for lumbar disc herniation: a prospective cohort study with 1-year follow-up. Journal of Neurosurgery
  Academic article
• Nygaard, Øystein P; Kloster, R; Solberg, T; Mellgren, SI. (2000) Recovery of function in adjacent nerve roots after surgery for lumbar disc herniation: use of quantitative sensory testing in the exploration of different populations of nerve fibers. Journal of spinal disorders
  Academic article
• Vik, Anne; Hulleberg, Gunn; Zwart, John-Anker; Nygaard, Øystein Petter. (2000) Langtidsoppfølging etter operasjon av lumbalt prolaps. Tidsskrift for Den norske legeforening
  Academic article

1999

• Nygaard, Øystein P.; Kloster, R.; Jacobsen, Eva Marie; Dullerud, Reidar. (1999) Nerve root signs on postoperative MR imaging. A prospective cohort study with contrast enhanced MRI in symptomatic and asymptomatic patients. Acta Neurochirurgica
  Academic article
• Nygaard, Øystein P.; Solberg, Terje; Jacobsen, Eva Marie; Kloster, R.; Dullerud, Reidar. (1999) Postoperative nerve root displacement and scar tissue. A prospective study with contrast enhanced MRI one year after microdiscectomy. Acta Radiologica
  Academic article

1998

• Sand, Trond; Nygaard, Øystein P. (1998) Quantitative EEG changes in acute mountain sickness. Acta Neurologica Scandinavica
  Academic article

1997

• Nygaard, Øystein P.; Solberg, Terje; Kloster, R.; Dullerud, Reidar; Jacobsen, Eva Marie; Mellgren, Svein Ivar. (1997) No association between peridural scar formation and outcome after lumbar microdiscectomy. A prospective cohort study with contrast enhanced MRI in symptomatic and asymptomatic patients. Acta Neurochirurgica
  Academic article