section name header

Information

Editors

TimoAalto

Lumbar Spinal Stenosis (Lss)

Essentials

  • The characteristic symptom of lumbar spinal stenosis (LSS) is neurogenic claudication (spinal claudication). When walking, the patient experiences pain (which usually starts in the back and radiates to the legs), numbness or weakness.
  • If the symptoms are tolerable and the patient's functional capacity is intact, the first-line management option is conservative treatment (including e.g. analgesia and physiotherapy).
  • Consider surgery, if needed, after 3-6 months of conservative treatment.
  • Indications for surgery include
    • unbearable or clearly interfering pain not relieved with conservative treatment
    • gradually shortening walking distance
    • progressing neurological deficit - LSS may be behind paraparesis
    • cauda equina syndrome (a rare situation: LSS usually progresses slowly).

Definition and epidemiology

  • Lumbar spinal stenosis denotes a stricture (stenosis) in the lumbar spine region, which may be either
    • a central stenosis (compression of the cauda equina in the spinal canal) or
    • a lateral stenosis (nerve root compression in the root canal or intervertebral foramen).
  • Degenerative changes are the most common cause of stenosis (ostephyte formation or ligament hypertrophy). Disc protrusion or prolapse may also be present.
  • Division into central and lateral forms is a radiological differentiation; mixed form LSS is the most common type.
  • Prevalence and incidence increase with age.
  • LSS is the most common reason for spinal surgery in patients aged over 65 years.
  • MRI and CT scans are carried out more than before, and consequently an increasing number of patients are diagnosed with LSS.

Symptoms and history

  • The most common symptom is neurogenic (spinal) claudication; when walking, the patient experiences pain (which usually starts in the back and radiates to the legs), numbness or weakness. The pain is usually relieved by sitting or leaning forward and worsened by extension.
  • Pain which is caused by chronic compression of a nerve root (”chronic sciatica”) is more persistent or manifests itself as numbness and paraesthesia; the symptoms may be localised to the affected dermatome or be more widespread.
  • The symptoms of LSS may be unilateral or bilateral. The intensity of pain often shows variation both from day to day and over the long term.
  • Patients may describe the symptoms in very different ways, and it is important to ask carefully about the location and nature of symptoms experienced during walking, exercise or at rest.
  • What distance can the patient walk on level ground without stopping? Does he/she stop due to claudication or for another reason?
  • Leaning forward for a prolonged period, exercise and even sitting may worsen the symptoms of LSS, particularly back pain. As is the case with all degenerative low back problems, reduced exercise tolerance of the back should be identified by taking a careful history, particularly when the symptoms threaten the patient's work capacity, since a physical examination of a patient with LSS may produce only a few findings.
  • Remember cauda equina symptoms and other critical "red flag" symptoms Low Back Pain.

Clinical findings

  • Patients with LSS-induced neurogenic claudication may be relatively asymptomatic when examined at rest, and findings of neurological examination may be completely normal. The importance of the history is thus emphasized.
  • If LSS is characterised with chronic nerve root compression, the patient may have pain when moving his/her back, and the SLR (straight leg raising) and Lasègue tests may be positive.
    • In the SLR test, the examiner raises the patient's straightened leg upwards by supporting it at the underside of the ankle so that the ankle remains free. In the Lasègue test the examiner has a hold on the patient's foot and keeps the ankle dorsiflexed in straight angle (90°) while raising the leg. In both tests, the examiner's other hand lies on the anterior surface of the patient's thigh to keep the knee straight.
  • Extension test: the patient is asked to fully extend his/her back whilst standing with the knees straight. The posture is held for 30-60 seconds. Low back pain/numbness provoked by the posture supports the diagnosis of LSS. The specificity of the test is not known.
  • Approximately half of the patients with LSS have sensory or reflex defects.
  • The pulses of the dorsal pedis artery and the posterior tibial artery should be palpated. A significant vascular occlusion may be excluded if the pulses are present, which will strengthen the suspicion of back problems as the cause of claudication.
  • Consider performing digital rectal examination (cauda equina compression; carcinoma of the prostate as the cause of back pain).

Diagnosis

  • The diagnosis of LSS is based on the history and clinical findings which must be supported by radiological abnormalities; decisions regarding radiological studies (MRI/CT) should be reserved for specialist physicians.
  • Plain radiograph of the back does not provide adequate information for LSS diagnosis and is not a necessary examination to be performed before an MRI is carried out.
  • Diagnostic criteria:
    • one or both of the following symptoms: neurogenic claudication or symptoms suggestive of chronic nerve root compression AND
    • radiologically confirmed cauda equina compression and/or nerve root compression (MRI, CT, rarely myelography).

Differential diagnosis

  • Back pain; differential diagnosis as for normal back pain Low Back Pain. Lower limb symptoms; differential diagnosis should take into account the possibility of local aetiology and other factors.
  • Vascular claudication Lower Limb Ischaemia
    • Pain usually in the calf and relieved by resting (flexing forward does not relieve pain); bicycling triggers claudication. Often abnormalities in pulse palpation.
  • Disc prolapse in the lumbar spine
    • Often a symptom that has appeared fairly rapidly in a younger patient. A positive nerve stretch test (Lasègue, femoral stretch test) is suggestive of a prolapse but does not exclude LSS.
  • Osteoarthritis of the hip and knee Osteoarthritis of the Hip and Knee, bursitis in the hip area Trochanteric Pain
  • Myelopathy as the cause of walking difficulties
    • Positive Babinski sign, spasticity of lower limbs and/or brisk reflexes should arouse suspicion.
  • Nerve entrapment involving a lower limb Nerve Entrapment and Compression Disorders
  • Neurological and other causes
  • Muscle trigger points at the lumbar spine/buttock/lower limb areas may cause local pain. Occasionally they will only cause non-specific reflex abnormalities (absent).
    • The trigger point may be anaesthetised as a diagnostic and therapeutic test.

Treatment

  • The outcome of patients with LSS is moderately good without surgery, and conservative treatment should therefore always be tried at first. ”Watchful waiting” may be sufficient for some patients.
  • Decompressive surgery and, if needed, fusion is more effective in symptomatic patients if 3 to 6 months of conservative treatment has failed.
  • The better results (pain, functional ability) achieved with surgical treatment in symptomatic LSS patients may last for up to 4 years. The benefit is reduced during 8 to 10 years of follow-up.

Conservative treatment

  • Indications for conservative treatment
    • The patient is able to tolerate the symptoms and daily functional capacity is adequate.
    • The patient does not want to be operated; assessment of surgery-related risks takes place usually within specialized care.
  • Encouragement to normal daily activities; appropriate aerobic exercise (e.g. "Nordic walking" with special walking poles similar to ski poles)
  • Reduction of significant overweight and cessation of smoking
  • At work: positions that alleviate pain, ergonomics, recovery pauses, rotation of work tasks
  • A lumbar corset may increase walking distance by over 30% and alleviate symptoms during strain.
  • Physiotherapy
    • Physiotherapy may reduce the need for surgical treatment within one-year follow-up, but it does not seem to improve functional capacity nor to reduce symptoms or use of medications.
    • Individually tailored easing of the pain and tightness of the myofascial tissues in the lower back and gluteal and thigh area, muscle activation exercises, self-care training programme
    • Front thigh tightness or poor condition of muscles in the abdominal, gluteal and posterior thigh areas may cause the pelvis to tilt forward (anterior pelvic tilt), which results in hyperlordosis (saddle back), extension of the lumbosacral spine and worsening of symptoms. Try to notice front thigh tightness (flexion of knee/extension of thigh, i.e. femoral stretching, while patient is lying in prone position/face down) and anterior tilt/saddle back and refer the patient for physiotherapy.
    • Also ultrasound and TNS therapies have been used as treatments.
  • Acupuncture
    • Treating L5 nerve root symptom with acupuncture for a period of 4 weeks yielded in one study a better result than exercise or drug therapy.
  • Analgesic medication
    • Analgesics (paracetamol, NSAIDs, mild opioids if necessary); dosage according to the intensity and appearance of symptoms, taking into account other medication and diseases
    • Vitamin B12, prostaglandins and gabapentin may increase walking distance.
    • Pregabalin alleviates symptoms in lower extremities and, when combined with a NSAID, may reduce need for surgical treatment.
    • Long-term use of opioids may be considered in refractory pain (whilst monitoring the response) after the diagnosis is verified if, for example, the patient will not benefit from surgery.
      • Strong opioids for long-term use should be initiated in specialist care (a physiatrist, a surgeon, a doctor at a pain clinic).
      • The treatment should be monitored according to local protocols.
  • Epidural anaesthetic blocks may provide short-term relief of pain and improvement of functional ability, but they have been associated with a risk of worse prognosis (pain, functional ability) in 4-year follow-up.

Surgical treatment

  • Surgical treatment for LSS has been shown to be effective and cost-effective in 4-year follow-up as compared to conservative treatment, and surgical treatment should be considered after 3 to 6 months of conservative treatment that has failed. Results of surgery become poorer if the preoperative symptoms that require surgery last for more than one year.
  • Preoperative use of analgesic drugs for more than 12 months is predictive of worse functional result in LSS patients who undergo surgery. Delaying the operation is hence not recommended, if the symptoms are severe and clinical-radiological indication exists.
  • Cauda equina syndrome and paraparesis require urgent surgical assessment. The development of degenerative LSS is usually slow.
  • Surgery is considered on the basis of radiologically confirmed stenosis compatible with the patient history and/or clinical findings.
  • Indications for surgery in LSS are considered to be
    • clearly disturbing or intolerable pain or significant functional impairment that are not relieved with conservative management
    • gradually shortening continuous walking distance (< 200-300 m).
      • The walking distance should, however, be set in proportion to other symptoms, diseases and the age of the patient. In a younger patient, a milder symptom may be relatively more impairing, and surgical treatment may occasionally be used even if the patient were able to walk over a kilometre.
  • About two out of three patients treated surgically are reported to have good to excellent outcomes. Cessation of smoking improves recovery from surgery. Attention should be pain on treatment of depressive symptoms both pre- and postoperatively because they are predictive of worse recovery. In LSS, preoperative factors predicting a better postoperative outcome include
    • pronounced constriction of the spinal canal
    • better walking ability and general health as assessed by the patient.
  • Factors predicting a worse postoperative outcome include
    • preoperative lumbar scoliosis
    • cardiovascular diseases
    • overweight (decreases satisfaction with the operation)
    • concomitant disease affecting walking ability (e.g. in concomitant hip osteoarthritis one should evaluate as to what extent the symptoms are caused by LSS and whether the patient will benefit from back operation).
  • A history of previous back operation as well as age over 75 years predict lower satisfaction with the operation, but the functional result in these patients is comparable to others.
  • It is not possible, however, to conclude from the predictive factors who warrants surgery.
  • Active postoperative rehabilitation on an outpatient basis may improve the functional treatment results, as well as pain in the back and lower extremities.

    References

    • Katz JN, Dalgas M, Stucki G, Lipson SJ. Diagnosis of lumbar spinal stenosis. Rheum Dis Clin North Am 1994 May;20(2):471-83. [PubMed]
    • Mazanec DJ, Podichetty VK, Hsia A. Lumbar canal stenosis: start with nonsurgical therapy. Cleve Clin J Med 2002 Nov;69(11):909-17. [PubMed]
    • Katz JN, Dalgas M, Stucki G et al. Degenerative lumbar spinal stenosis. Diagnostic value of the history and physical examination. Arthritis Rheum 1995 Sep;38(9):1236-41. [PubMed]
    • Hurri H, Slätis P, Soini J, Tallroth K, Alaranta H, Laine T, Heliövaara M. Lumbar spinal stenosis: assessment of long-term outcome 12 years after operative and conservative treatment. J Spinal Disord 1998 Apr;11(2):110-5. [PubMed]
    • Onel D, Sari H, Dönmez C. Lumbar spinal stenosis: clinical/radiologic therapeutic evaluation in 145 patients. Conservative treatment or surgical intervention? Spine 1993 Feb;18(2):291-8. [PubMed]
    • Johnsson KE, Rosén I, Udén A. The natural course of lumbar spinal stenosis. Clin Orthop Relat Res 1992 Jun;(279):82-6. [PubMed]
    • Rydevik BL, Cohen DB, Kostuik JP. Spine epidural steroids for patients with lumbar spinal stenosis. Spine 1997 Oct 1;22(19):2313-7. [PubMed]
    • Jönsson B, Annertz M, Sjöberg C, Strömqvist B. A prospective and consecutive study of surgically treated lumbar spinal stenosis. Part II: Five-year follow-up by an independent observer. Spine 1997 Dec 15;22(24):2938-44. [PubMed]
    • Herno A, Airaksinen O, Saari T, Miettinen H. The predictive value of preoperative myelography in lumbar spinal stenosis. Spine 1994 Jun 15;19(12):1335-8. [PubMed]
    • Katz JN, Stucki G, Lipson SJ, Fossel AH, Grobler LJ, Weinstein JN. Predictors of surgical outcome in degenerative lumbar spinal stenosis. Spine 1999 Nov 1;24(21):2229-33. [PubMed]
    • Iversen MD, Daltroy LH, Fossel AH, Katz JN. The prognostic importance of patient pre-operative expectations of surgery for lumbar spinal stenosis. Patient Educ Couns 1998 Jun;34(2):169-78. [PubMed]
    • Frazier DD, Lipson SJ, Fossel AH, Katz JN. Associations between spinal deformity and outcomes after decompression for spinal stenosis. Spine 1997 Sep 1;22(17):2025-9. [PubMed]
    • Aalto TJ, Malmivaara A, Kovacs F et al. Preoperative predictors for postoperative clinical outcome in lumbar spinal stenosis: systematic review. Spine 2006 Aug 15;31(18):E648-63. [PubMed]
    • Turner JA, Ersek M, Herron L, Deyo R. Surgery for lumbar spinal stenosis. Attempted meta-analysis of the literature. Spine 1992 Jan;17(1):1-8. [PubMed]
    • Weinstein JN, Tosteson TD, Lurie JD et al; SPORT Investigators. Surgical versus nonsurgical therapy for lumbar spinal stenosis. N Engl J Med 2008 Feb 21;358(8):794-810. [PubMed]
    • Malmivaara A, Slätis P, Heliövaara M, et al; Finnish Lumbar Spinal Research Group. Surgical or nonoperative treatment for lumbar spinal stenosis? A randomized controlled trial. Spine 2007;32:1-8 [PubMed]
    • Atlas SJ, Keller RB, Wu YA, Deyo RA, Singer DE. Long-term outcomes of surgical and nonsurgical management of lumbar spinal stenosis: 8 to 10 year results from the maine lumbar spine study. Spine 2005 Apr 15;30(8):936-43. [PubMed]
    • Kovacs FM, Urrútia G, Alarcón JD. Surgery versus conservative treatment for symptomatic lumbar spinal stenosis: a systematic review of randomized controlled trials. Spine (Phila Pa 1976) 2011;36(20):E1335-51. [PubMed]
    • Weinstein JN, Tosteson TD, Lurie JD et al. Surgical versus nonoperative treatment for lumbar spinal stenosis four-year results of the Spine Patient Outcomes Research Trial. Spine (Phila Pa 1976) 2010;35(14):1329-38. [PubMed]
    • Ammendolia C, Stuber K, de Bruin LK et al. Nonoperative treatment of lumbar spinal stenosis with neurogenic claudication: a systematic review. Spine (Phila Pa 1976) 2012;37(10):E609-16. [PubMed]
    • Radcliff K, Kepler C, Hilibrand A et al. Epidural steroid injections are associated with less improvement in patients with lumbar spinal stenosis: a subgroup analysis of the Spine Patient Outcomes Research Trial. Spine (Phila Pa 1976) 2013;38(4):279-91. [PubMed]
    • Tosteson AN, Tosteson TD, Lurie JD et al. Comparative effectiveness evidence from the spine patient outcomes research trial: surgical versus nonoperative care for spinal stenosis, degenerative spondylolisthesis, and intervertebral disc herniation. Spine (Phila Pa 1976) 2011;36(24):2061-8. [PubMed]
    • Sinikallio S, Aalto T, Airaksinen O et al. Depression is associated with a poorer outcome of lumbar spinal stenosis surgery: a two-year prospective follow-up study. Spine (Phila Pa 1976) 2011;36(8):677-82. [PubMed]
    • Aalto T, Sinikallio S, Kröger H et al. Preoperative predictors for good postoperative satisfaction and functional outcome in lumbar spinal stenosis surgery--a prospective observational study with a two-year follow-up. Scand J Surg 2012;101(4):255-60. [PubMed]
    • Sandén B, Försth P, Michaëlsson K. Smokers show less improvement than nonsmokers two years after surgery for lumbar spinal stenosis: a study of 4555 patients from the Swedish spine register. Spine (Phila Pa 1976) 2011;36(13):1059-64. [PubMed]
    • Knutsson B, Michaëlsson K, Sandén B. Obesity is associated with inferior results after surgery for lumbar spinal stenosis: a study of 2633 patients from the Swedish spine register. Spine (Phila Pa 1976) 2013;38(5):435-41. [PubMed]
    • Fritz JM, Lurie JD, Zhao W et al. Associations between physical therapy and long-term outcomes for individuals with lumbar spinal stenosis in the SPORT study. Spine J 2014;14(8):1611-21. [PubMed]
    • Takahashi N, Arai I, Kayama S et al. Therapeutic efficacy of pregabalin in patients with leg symptoms due to lumbar spinal stenosis. Fukushima J Med Sci 2014;60(1):35-42. [PubMed]
    • Takahashi N, Arai I, Kayama S et al. One-year follow-up for the therapeutic efficacy of pregabalin in patients with leg symptoms caused by lumbar spinal stenosis. J Orthop Sci 2014;19(6):893-9. [PubMed]
    • Radcliff KE, Rihn J, Hilibrand A et al. Does the duration of symptoms in patients with spinal stenosis and degenerative spondylolisthesis affect outcomes?: analysis of the Spine Outcomes Research Trial. Spine (Phila Pa 1976) 2011;36(25):2197-210. [PubMed]
    • Pearson A, Lurie J, Tosteson T et al. Who should have surgery for spinal stenosis? Treatment effect predictors in SPORT. Spine (Phila Pa 1976) 2012;37(21):1791-802. [PubMed]
    • Kuittinen P, Sipola P, Leinonen V et al. Preoperative MRI findings predict two-year postoperative clinical outcome in lumbar spinal stenosis. PLoS One 2014;9(9):e106404. [PubMed]
    • Rihn JA, Hilibrand AS, Zhao W et al. Effectiveness of surgery for lumbar stenosis and degenerative spondylolisthesis in the octogenarian population: analysis of the Spine Patient Outcomes Research Trial (SPORT) data. J Bone Joint Surg Am 2015;97(3):177-85. [PubMed]
    • Schroeder JE, Hughes A, Sama A et al. Lumbar Spine Surgery in Patients with Parkinson Disease. J Bone Joint Surg Am 2015;97(20):1661-6. [PubMed]
    • Freedman MK, Hilibrand AS, Blood EA et al. The impact of diabetes on the outcomes of surgical and nonsurgical treatment of patients in the spine patient outcomes research trial. Spine (Phila Pa 1976) 2011;36(4):290-307. [PubMed]
    • Ammendolia C, Rampersaud YR, Southerst D ym. Effect of a prototype lumbar spinal stenosis belt versus a lumbar support on walking capacity in lumbar spinal stenosis: a randomized controlled trial. Spine J 2018[PubMed]
    • Oka H, Matsudaira K, Takano Y ym. A comparative study of three conservative treatments in patients with lumbar spinal stenosis: lumbar spinal stenosis with acupuncture and physical therapy study (LAP study). BMC Complement Altern Med 2018;18(1):19. [PubMed]