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A 45-year-old patient complains of leg pain associated with the pathology seen in Figure A. The patient undergoes microdiskectomy. During surgery there is no evidence of instability. Ten months later he
re-develops similar symptoms of leg pain. A repeat MRI is consistent with a recurrent lumbar disc herniation. Which of the following most accurately describes the outcomes of revision surgery in comparison to primary surgery?
Equal limb pain and equal functional outcomes
Improved limb pain and improved functional outcomes
Worsened limb pain and worsened functional outcomes
Worsened limb pain but improved functional outcomes
Improved limb pain but worsened functional outcomes
Select Answer to see Preferred Response
The clinical presentation is consistent with a recurrent lumbar disc herniation. Revision lumbar discectomy has been shown to have outcomes (pain and function) equal to that of primary lumbar discectomy.
Recurrent lumbar disc herniation is a common complication of lumbar discectomy procedure. These entities may initially be treated with anti-inflammatories, physical therapy and rest. If those initial measures do not work, selective nerve root injections can be used (epidural/selective nerve blocks). If these measures fail, then revision lumbar discectomy is the best surgical option; if there is evidence of instability at the level in question, a fusion procedure would be indicated.
Stambough et al. review management of recurrent lumbar disk herniations. They note that the majority of these cases can be treated conservatively. In cases where surgery is indicated, revision lumbar discectomy is the procedure of choice.
Patel et al. retrospectively reviewed 30 patients who had undergone primary and revision lumbar spine discectomy. Outcomes assessed were Visual Analogue Scales for back and limb pain (VAB & VAL) and the Oswestry Disability Index (ODI). They found similar, statistically significant improvements in limb pain and ODI scores. They conclude that revision discectomy can achieve results as good as those after primary discectomy.
Figure A shows a sagittal T2 weighted MRI sequence of a disk herniation at the L4-L5 level.
Answer 2, 3, 4, 5: Revision lumbar discectomy has been shown to have as good outcomes in terms of pain and function as primary lumbar discectomy.
Patel MS, Braybrooke J, Newey M, Sell P.
Bone Joint J. 2013 Jan;95-B(1):90-4. PMID: 23307679 (Link to Abstract)
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Average 2.0 of 24 Ratings
In patients with a symptomatic lumbar disc herniation who have failed nonoperative management, which of the following patient characteristics are associated with improved treatment effects with surgery?
Duration of symptoms > 6 mos, improving symptoms at baseline, Mental Component Score (MCS) > 35
Duration of symptoms < 6 mos, worsening symptoms at baseline, Mental Component Score (MCS) > 35
Age > 41 years, divorced, presence of worker compensation claim
Age < 31 years, absence of joint problems, no workers compensation
Age > 41 years, absence of joint problems, married status
Age > 41 years, absence of joint problems, and married status are associated with improved treatment effects in patients having surgery for lumbar disc herniation.
Lumbar disc herniations are a common cause of low back and leg pain. In the vast majority (>90%) the symptoms improve with nonoperative treatment within 3 months. However, a subset of patients have persistent pain and require surgery. Variables have been associated with outcomes with surgical treatment. The most frequently described is that workers compensation patients have worse surgical outcomes.
Weinstein et al. in the SPORT study found that in a combined as-treated analysis at 4 years, patients who underwent surgery for a lumbar disc herniation achieved greater improvement than nonoperatively treated patients in all primary and secondary outcomes except work status.
Pearson et al. in the SPORT study found the following patient characteristics were associated with improved treatment effects with surgical intervention for lumbar disc herniation: age > 41 years, absence of joint problems, a high school education or less, no worker’s compensation, duration of symptoms for over 6 months, being married, worsening symptom trend at baseline, and Mental Component Score (MCS) of less than 35.
Nguyen et al. looked at a cohort of Worker's Compensation patients and their outcomes following lumbar fusion. They found lumbar fusion for the diagnoses of disc degeneration, disc herniation, and/or radiculopathy in a Workers Compensation setting is associated with significant increase in disability, opiate use, prolonged work loss, and poor RTW status.
Illustration A shows the two most common positions of a lumbar disc herniation (paracentral-blue and foraminal-red). Illustration B shows a paracentral disc herniation at L4/5 on an axial MRI and shows how it affects the descending (L5) nerve root. Illustration C shows a foraminal disc herniation at L4/5 on an axial MRI, and how it affects the exiting (L4) nerve root.
Answer 1: Worsening symptoms at baseline and Mental Component Score (MCS) < 35 are associated with improved treatment effects.
Answer 2: Duration of symptoms > 6 mos and Mental Component Score (MCS) < 35 are associated with improved treatment effects.
Answer 3: Married and absence of worker compensation claim are associated with improved treatment effects.
Answer 4: Age > 41 years are associated with improved treatment effects.
Weinstein JN, Lurie JD, Tosteson TD, Tosteson AN, Blood EA, Abdu WA, Herkowitz H, Hilibrand A, Albert T, Fischgrund J
Spine. 2008 Dec;33(25):2789-800. PMID: 19018250 (Link to Abstract)
Pearson A, Lurie J, Tosteson T, Zhao W, Abdu W, Mirza S, Weinstein J
Spine. 2012 Jan;37(2):140-9. PMID: 21681140 (Link to Abstract)
Nguyen TH, Randolph DC, Talmage J, Succop P, Travis R.
Spine (Phila Pa 1976). 2011 Feb 15;36(4):320-31. PMID: 20736894 (Link to Abstract)
Average 1.0 of 65 Ratings
A 38-year-old male presents with a three month history of low back pain and right leg pain that has failed to improve with nonoperative modalities including selective nerve root corticosteroid injections. Leg pain and paresthesias are localized to his buttock, lateral and posterior calf, and the dorsal aspect of his foot. On strength testing, he is graded a 4/5 for plantar-flexion and 4+/5 to ankle dorsiflexion. On flexion and extension radiographs there is no evidence of spondylolisthesis. Sagittal and axial T2-weighted MRI images are shown in Figure A and B. Which of the following treatment modalities will allow the greatest improvement of physical functioning?
Medical management with GABA analogs
Disectomy and instrumented fusion
The clinical presentation is consistent for a lumbar disc herniation with symptoms of a combined L5 and S1 radiculopathy that has failed to improve with extensive nonoperative treatment. At this time a discectomy would lead to the greatest improvement in physical functioning.
Anderson et al. reviewed the adequacy of randomized controlled studies completed over 25 years (1983-2007) that attempted to compare discectomy with non-surgical treatment. Given the high crossover rates and heterogeneity of outcome measures, the authors are unable to make conclusions as to the benefit of one treatment modality over another.
Weinstein et al. reviewed greater than 1000 patients who had imaging confirmed lumbar disc herniations; treatment modalities were non operative or operative (discectomy). Significant improved in physical function, bodily pain and disability scales were seen at even 4 years postoperatively.
Figures A and B show the axial and sagittal sequences of a T2-weighted MRI of the lower lumbar spine. A large L5/S1 para-central disc herniation is seen that has migrated cephalad. Therefore, it is irritating both the exiting L5 nerve root and descending S1 nerve root.
Answers 1, 2, 3: Many (> 90%) disc herniations have a self-limited natural history; the symptoms may be alleviated by bedrest and activites as tolerated, administration of anti-inflammatories or GABA analogs and completion of physical therapy. For symptoms that persist greater than 6 weeks and are disabling, surgery is indicated. Recent data from the SPORT trial suggests that functional outcomes may be improved by completion of discectomy.
Answers 5: Completion of a discectomy and instrumented fusion is not indicated in this patient. Without evidence of degenerative changes in the lumbar spine or evidence of spondylolisthesis, a posterior spinal instrumented fusion is not warranted.
Anderson PA, McCormick PC, Angevine PD.
J Am Acad Orthop Surg. 2008 Oct;16(10):566-73. PMID: 18832600 (Link to Abstract)
Average 3.0 of 13 Ratings
A 33-year-old woman reports pain down her right leg and numbness across the dorsum of her right foot which started 3 months ago during a bowel movement. Prior to this she had had 1 month of low back pain. She had a lumbar microdiscectomy at L4/5 3 years ago which was successful. On physical exam she has weakness to ankle dorsiflexion and great toe extension on the right. Her new radiograph and MRI images are shown in Figure A and B respectively. After a failure of nonoperative treatment, which of the following is the most appropriate surgical treatment?
L4/5 microdiskectomy through midline approach
L4/5 microdiskectomy with far lateral Wiltse approach
L4/5 Decompression, TLIF, and instrumented fusion
L4/5 Decompression, PLIF, and instrumented fusion
L4/5 Anterior Lumbar Interbody Fusion
The clinical presentation is consistent with a recurrent lumbar disc herniation. If conservative measures fail, the most appropriate treatment is revision microdiskectomy.
Papadopoulos et al. looked at a total of 27 patients who had undergone revision discectomies for recurrent lumbar disc herniation. They found revision discectomy is as successful as primary discectomy for patient satisfaction and function.
Suk et al. studied conventional discectomy for treatment of recurrent lumbar disc herniation and found results to be comparable to discectomy for a primary herniation.
Answer 2: A L4/5 microdiskectomy with far lateral Wiltse approach is indicated in a far lateral or foraminal disc herniation. An example of a far lateral disc herniation is shown in Illustration A.
Answer 3,4,5: A fusion would not be indicated at this time, as there is no sign of instability or spondylolisthesis.
Papadopoulos EC, Girardi FP, Sandhu HS, Sama AA, Parvataneni HK, O'Leary PF, Cammisa FP Jr.
Spine (Phila Pa 1976). 2006 Jun 1;31(13):1473-6. PMID: 16741457 (Link to Abstract)
Suk KS, Lee HM, Moon SH, Kim NH.
Spine (Phila Pa 1976). 2001 Mar 15;26(6):672-6. PMID: 11246384 (Link to Abstract)
Average 3.0 of 23 Ratings
A 35-year-male presents with pain radiating down the left leg, worse in the anterior leg distal to the knee. On physical exam, he is unable to go from a sitting position to a standing position with a single leg on the left, whereas he has no difficulty on the right. His patellar reflex is absent on the left, and 2+ on the right. Which of the following clinical scenarios would best produce this pattern of symptoms?
Left L2-3 foraminal herniated nucleus pulposis
Left L4-5 central herniated nucleus pulposis
Left L4-5 paracentral herniated nucleus pulposis
Left L4-5 foraminal herniated nucleus pulposis
Left L5-S1 paracentral herniated nucleus pulposis
This clinical scenario describes a patient presenting with an L4 radiculopathy. This is supported by his decreased patellar reflex and quadriceps weakness. A L4-5 foraminal (far lateral) herniated nucleus pulposis would most likely cause symptoms in the L4 distribution as foraminal herniations most commonly affect the exiting upper nerve root at a given lumbar level.
Rainville et al performed a study to identify the most sensitive physical exam test to detect quadriceps weakness caused by either an L3 or L4 radiculopathy. They found in L3 and L4 radiculopathies, unilateral quadriceps weakness was detected by the single leg sit-to-stand test in 61%, by knee-flexed manual muscle testing in 42%, by step-up test in 27% and by knee-extended manual muscle testing in 9% of patients. They conclude in L3 and L4 radiculopathies, unilateral quadriceps weakness was best detected by a single leg sit-to-stand test.
Deyo et al review the history, presentation, physical exam findings, and conservative treatment aimed at lumbar disk herniations. They describe the treatment modalities recommended (NSAIDS and early progressive mobilization) and those which are not recommended (narcotics and muscle relaxants). Physical examination maneuvers aimed at ruling out a diagnosis of cauda equina syndrome are imperative to understand and document as cauda equina syndrome is a surgical emergency.
Illustration A shows the location of different types of disk herniations. The red circle shows the location of a foraminal (far lateral) disc herniation. The blue circle shows the location of a paracentral disc herniation. Illustration B shows a T2 axial image of a foraminal (far lateral) disc herniation. Illustration C shows a T2 axial image of a paracentral disc herniation. Illustration D describes the difference between the cervical spine and lumbar spine with respect to nerve root anatomy.
Rainville J, Jouve C, Finno M, Limke J
Spine. 2003 Nov;28(21):2466-71. PMID: 14595165 (Link to Abstract)
Deyo RA, Loeser JD, Bigos SJ.
Ann Intern Med. 1990 Apr 15;112(8):598-603. PMID: 2139310 (Link to Abstract)
Average 4.0 of 31 Ratings
Following surgical treatment of a lumbar disc herniations with radiculopathy, patients with worker's compensation claims have which of the following when compared to patients who do not have worker's compensation claims at 5 years?
Equivalent relief from symptoms and equivalent improvement in quality of life
Less relief from symptoms and less improvement in quality of life
Improved relief from symptoms and greater improvement in quality of life
Significantly decreased return to work status
Significantly improved return to work status
Patients with worker's compensation claims have less relief from symptoms and less improvement in quality of life following surgical treatment of lumbar disc herniations. Despite this, they have near equivalent return to work status at 4 years.
Atlas et al. (2006) showed at 5-10 years, most patients, regardless of baseline workers' compensation status, were employed (78% for both groups). However, workers' compensation patients had worse symptoms, functional status, and satisfaction outcomes.
Atlas et al. (2000) found patients who had been receiving Workers' Compensation at baseline had significantly less relief from symptoms and less improvement in quality of life, however, they were only slightly less likely to be working at the time of the four-year follow-up.
Atlas SJ, Chang Y, Keller RB, Singer DE, Wu YA, Deyo RA.
Spine (Phila Pa 1976). 2006 Dec 15;31(26):3061-9. PMID: 17173004 (Link to Abstract)
Atlas SJ, Chang Y, Kammann E, Keller RB, Deyo RA, Singer DE
J Bone Joint Surg Am. 2000 Jan;82(1):4-15. PMID: 10653079 (Link to Abstract)
Average 2.0 of 44 Ratings
A 40-year-old female presents with right leg pain localized to the buttock, posterior thigh, and lateral calf. In addition, she describes numbness and tingling on the dorsum of the right foot. Physical exam shows weakness to EHL. Three months of nonoperative treatment including anti-inflammatory medication, physical therapy, and selective nerve root corticosteroid injections failed to provide lasting relief and pain is still severe in nature. Her MRI is shown in Figures A and B. What would be the most appropriate management at this juncture?
Refer the patient to pain management
Repeat epidural steroid injection
Laminotomy and diskectomy
Spinal fusion with interbody cage and posterior instrumentation
The patients clinical presentation and imaging studies are consistent with a L5 radiculopathy caused by a right paracentral disc herniation at L4/5 which is compressing the L5 nerve root. Because she has failed nonoperative management a laminotomy and diskectomy would be the most appropriate treatment.
A L4/5 paracentral disc involves the L5 nerve root. The muscles innervated by L5 nerve root include EHL and tibialis anterior, and therefore these patients may present with a "foot drop". While EHL is usually innervated by L5 alone, tibialis anterior has variable innervation by L4 and L5.
Weinstein et al. (SPORT 2 year results) showed as-treated analysis (prospective nonrandomized), discectomy was favorable with quicker improvement in symptoms for patients with surgery. They warn that the SPORT intent-to-treat analysis (prospective randomized) showed no statistical difference between those who had diskectomy vs. those who did not, but this data was disrupted by a very high crossover rate, and therefore most consider the as-treated analysis as a more accurate representation of the true clinical effect of treatment.
Weinstein et al (SPORT 4 year results) showed in the as-treated analysis that patients treated surgically for intervertebral disc herniation showed significantly greater improvement in pain, function, satisfaction, and self-rated progress over 4 years compared to patients treated non-operatively. They found at four years there was no significant difference in work status between the surgical and nonsurgical group.
Weber et al. look at a cohort that was randomized into surgical and non-surgical treatment for lumbar disc herniations. They found the controlled trial showed a statistically significant better result in the surgically treated group at the one-year follow-up examination. After four years the operated patients still showed better results, but the difference was no longer statistically significant.
Illustration A shows the lower extremity dermatomes. Illustration B shows how a laminotomy is used to access the disc and how an paracentral disc will affect the descending nerve root. Illustration C shows the difference between a laminotomy, hemilaminectomy, and laminectomy.
Weinstein JN, Lurie JD, Tosteson TD, Skinner JS, Hanscom B, Tosteson AN, Herkowitz H, Fischgrund J, Cammisa FP, Albert T, Deyo RA
JAMA. 2006 Nov;296(20):2451-9. PMID: 17119141 (Link to Abstract)
Weinstein JN, Tosteson TD, Lurie JD, Tosteson AN, Hanscom B, Skinner JS, Abdu WA, Hilibrand AS, Boden SD, Deyo RA.
JAMA. 2006 Nov 22;296(20):2441-50. PMID: 17119140 (Link to Abstract)
Spine (Phila Pa 1976). 1983 Mar;8(2):131-40. PMID: 6857385 (Link to Abstract)
Average 4.0 of 20 Ratings
A 45-year-old male comes into your clinic complaining of right leg radicular pain that extends to the dorsal aspect of his right foot. On physical exam he has slight decreased sensation on the top of his right foot as well as 3/5 strength in his right EHL. He has 5/5 strength in the all other muscle groups in his lower extremities and symmetric 1+ patellar and Achilles reflexes bilaterally. Which axial MRI would be consistent with the patients symptoms
The patient presents with a right sided L5 radiculopathy. The only axial MRI image that would cause a right L5 radiculopathy is Figure E, a far lateral L5/S1 disc herniation.
Radiculopathy secondary to a herniated lumbar disc can affect either the traversing nerve root or the exiting nerve root. Paracentral disc herniations are most common, and they affect the traversing nerve root, i.e. an L5/S1 paracentral disc herniation will cause S1 symptoms. Occasionally disc herniations are far lateral. In these cases, the disc herniation affects the exiting nerve root, i.e. an L5/S1 far lateral disc herniation will cause L5 symptoms.
Tamir et al reported that far lateral disc herniations are more common at L3/4 than L4/5 or L5/S1. Additionally, L3/4 disc herniations are more likely to be in older patients, and neurologic deficits are common.
Rhee et al. published a review on the anatomy, pathophysiology and treatment options for lumbar herniated discs.
Illustration A is a schematic showing how paracentral and far lateral disc herniations affect the traversing and exiting nerve roots respectively. Illustration B labels the anatomic structure in the axial MRI in Figure E.
Answer 1: This is a far lateral disc herniation at L4/5. This would present with right L4 symptoms
Answer 2: This is a facet cyst at L4/5. It would present with left L5 symptoms
Answer 3: This is a paracentral disc herniation at L3/4. This would present with right L4 symptoms
Answer 4: This is a paracentral disc herniation at L5/S1. This would present with right S1 symptoms
Tamir E, Anekshtein Y, Melamed E, Halperin N, Mirovsky Y.
J Spinal Disord Tech. 2004 Dec;17(6):467-9. PMID: 15570116 (Link to Abstract)
Rhee JM, Schaufele M, Abdu WA.
J Bone Joint Surg Am. 2006 Sep;88(9):2070-80. PMID: 17036418 (Link to Abstract)
Average 3.0 of 49 Ratings
In patients with lumbar disc herniations resulting in significant unilateral leg pain but no functionally limiting weakness, surgical decompression has what long term effects when compared to nonoperative management?
Worse outcomes in pain, physical function, and return to work status at 4 years.
Equivalent outcome in pain and physical function at 4 years.
Improved outcome in pain and physical function at 4 years.
Improved outcome in return to work status only at 4 years.
Worse outcome in return to work status with equivalence in pain and physical function at 4 years.
Recent evidence now supports that patients who undergo surgery for lumbar disc herniation have improved outcomes in bodily pain and physical function at 4 years.
Weinstein et al showed in the as-treated analysis that patients treated surgically for intervertebral disc herniation showed significantly greater improvement in pain, function, satisfaction, and self-rated progress over 4 years compared to patients treated non-operatively. They found at four years there was no significant difference in work status between the surgical and nonsurgical group.
Answer 1,2 &5: Surgical patients have improved outcomes in pain, physical function, at 4 years.
Answer 4: There is no difference in work status at 4 years.
Average 3.0 of 31 Ratings
A far lateral disc herniation at the L4/5 level would likely present with what neurologic symptoms and physical finding.
Weakness to hip flexion, numbness on the inner thigh, a decreased patellar reflex
Weakness to knee extension, numbness on the anterior shin, a decreased patellar reflex
Weakness to ankle dorsal flexion, numbness on the dorsal foot, a decreased Achilles reflex
Weakness to extensor hallicus longus, numbness in the first web space, a decreased Achilles reflex
Weakness to ankle plantar flexion, numbness on the lateral foot, normal reflexes
This is a basic anatomy question. A far lateral disc herniation affects the exiting nerve root. At the L4/5 level this would be the L4 nerve root. The L4 nerve root innervates knee extension, the patellar reflex, and a sensory distribution that travels over the knee into the anterior shin. (see illustration A). Illustration B demonstrates the ASIA Classification of Spinal Injury diagram which also depicts ankle dorsiflexion as a test for L4.
HPI - The patient is 59-year-old male that was moving a tree branch when he developed severe pain in his left leg 10 days ago. He localizes the pain to his knee and his medial calf and ankle. He reports his pain was so severe initially he could not get off the ground, and has remained severe enough that he is unable to perform ADL, and is having difficulty sleeping. He was given a steroid taper and narcotics by his PCP, but his symptoms remained severe so an MRI was performed and he was referred to my office. He does report initially he could not "extend his knee", but reports that is improving.
Would you operate on this patient acutely
In this video Dr. Jeffrey P. Johnson explains how to identify a far lateral lumb...
Average 2.0 of 57 Ratings
45-year-old manual laborer presents to the office with acute onset back pain that radiates to his right leg after carrying a heavy object. He also has mild non-progressive weakness with ankle dorsiflexion on that side. A representative MRI cut is shown in Figure A. What should be his initial treatment?
Posterior spinal fusion with instrumentation
Anti-inflammatory medication and physical therapy
Lumbar disc herniation is the most common cause of radicular pain in the adult working population. 95% of these herniations involve L4/5, L5/S1 lumbar disc spaces. Patients typically present with low back pain and sharp stabbing leg pain with sensory symptoms in a specific dermatomal distribution. Persistent intractable pain following non-surgical treatment during a minimum 6 week period is the most frequent indication for surgery.
The Weber article was a RCT over 10 yrs of 126 pt with sciatica due to herniated lumbar discs. The results of surgical treatment were significantly better than the results in the conservatively treated group after one year of observation, however this difference became much less pronounced after nine more years.
Saal et al retrospectively reviewed 11 patients treated nonoperatively with lumbar disc extrusions through CT/MRI to evaluate disc morphology initially and at follow up (mean 25 mos). Only 1 patient had progression of stenosis, and all patients had disc dessication at the level of disc herniation with contiguous levels being normally hydrated. All patients had a decrease in neural impingement.
Saal JA, Saal JS, Herzog RJ.
Spine (Phila Pa 1976). 1990 Jul;15(7):683-6. PMID: 2218716 (Link to Abstract)
Average 3.0 of 25 Ratings
HPI - 69 ys old female patient ..complaining of LBP with rt sciatica
Based on the MRI shown, what do you think is the lesion seen in the right paracentral space with displacement of the thecal sac.
HPI - Patient is 32-year old orthopedic surgeon with history of right side S1 radiculopathy for 8 months that progressed to bilateral S1 radiclopathy for last 3 months. Epidural steroid injection after 1st 2 month did not lead to improvement in sign and symptom. No complaints of muscle weakness and no bladder or bowel involvement.
Paraesthesia improved after first 3 month. Pain last 2 month increase , interfere significantly with daily activity
Lumbar discectomy performed in 4 / 12 / 2013.
Fenestration done and sequestrectomy done .
Surgeon how did the surgery tell me he found all disc sequestrated annulus healed no any further compression on root .
Bleeding from epidural vein occur , gel foam
Postop. No any improvement ,still bilateral S1 radiculopathy more sever in right side with intermitten throbbing pain in right paraspinal area at level of sacral ala at rest With Backache
The pain even more intense than preoperative p
what your opnion about the case
HPI - The patient presents with 6 week hx of rt side leg pain and paraesthesia below knee in the S1 dermatome. He has a mild backache, no fever, no weakness. Pain intensity changes with position. It is mild in the morning and increases gradually. It is worse with sitting more than 30 minutes. Current management with NSAISs and physical therapy.
What would be your next step in management for this patient?
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