Lumbar Spinal Stenosis is a narrowing of the space between vertebrae where the spinal cord and the spinal nerves travel.
It is a diagnostic term to describe lower back pain with or without weakness and loss of sensation in the legs. It is a very common condition brought on mostly by aging and the accompanying degeneration of the spine.
As we age, discs compress, muscles, ligaments, and tendons weaken. With the spine weakened, the boney structures of the vertebrae begin to overgrow (osteoarthritis) as a means to stabilize the structure. The new boney mass begins to encroach on the openings in the spine that the nerves and spinal canal pass through. As the openings begin to narrow, the spinal canal and nerves rub against the bone causing irritation, inflammation and the symptoms of stenosis mentioned above.
In this article I will discuss the different types of injections that may be used to treat spinal stenosis including epidural steroid injections.
Many patients come into our office with a date for surgery or, and more unfortunate, a diagnosis of failed back surgery. For the patients who had put off surgery, they have explored their options and have discovered that surgery is not the answer for them. For the patients who had the surgery, they need more options than before.
In the recommended surgical procedures for spinal stenosis, two choices are the most favored. A decompression procedure where the surgeon will shave and cut away the bone narrowing the spinal canals. The second, a fusion procedure to limit the movement between two vertebrae and hopefully stop the compression of nerves.
Surgery for spinal stenosis should be considered only after other conservative therapies have been exhausted because it is usually not as successful as hoped and leads to a new diagnosis “failed back surgery syndrome,” where symptoms continue to deteriorate. It is important to note that in instances where stenosis is so severe that the patient has lost circulation to the legs or bladder control – a surgical consult should be made immediately.
Many “conservative” or non-surgical treatment options include the use of anti-inflammatories or epidural cortisone injections. We avoid the use of these treatments as they are temporary “quick-fixes.” The medical literature is now long in studies that have shown that these treatments are contributors to accelerated deterioration of spinal and joint degeneration.
Osteoarthritis occurs because the bone is trying to stabilize a joint. Fusion surgery is recommended as a means to accelerate that type of stabilization – the use of bone for stabilization. Stem cell therapy and Platelet Rich Plasma therapies work a completely different way. It stabilizes by strengthening the often forgotten and under appreciated spinal ligaments and tendons.
Bone marrow concentrate injections: Two case studies.
Two case studies we recently published research in the Biomedical Journal of Scientific & Technical Research.(1)
- The patient was a 77 year-old female with a 20-year history of lower back pain, which had progressed with age.
- The patient wore a back brace to attempt to reduce the stiffness and pain when standing or sitting for extended periods of time.
- Radiographic assessment of her lumbar spine showed mild dextroscoliosis (a sideways curve) and
- a mild narrowing of L1-L2, L3-L4 and moderately severe narrowing of L5-S1.
- Her baseline resting and active pain prior to treatment was:
- 1/10 (resting) and 5/10 (active), and a 33/40 functionality score.
After physical assessment of her lower back, we determined her pain was generated from a lumbosacral sprain. Not the narrowing of the L1-L5,S1.
She had one Bone marrow derived stem cell injection treatment and at first follow up two weeks after the injections, the patient experienced no pain or stiffness and reported 90% total improvement. Approximately a year after injection treatment, she felt even better, and stated that she was able to perform aerobics and line dancing for an hour and a half a day with no pain. She reported infrequent stiffness, but not as severe as it was prior to treatment.
Her resting and active pain were 0/10 and functionality score was 39/40.
The second case: a 56-year-old male who had a two-year history of lower back pain
- The patient reported pain that was most prominent when sitting or lying on his stomach. MRI of his lumbar spine demonstrated moderate L3-L4 central stenosis due to a broad based disc bulge and facet degenerative change with hypertrophy.
- The patient underwent an epidural injection, physical therapy, and massage therapy none of which provided consistent pain relief.
- His resting pain was 3/10, active pain was 6/10, and functionality score was 17/40 at baseline.
- When I examined his lower back, the patient was diagnosed with a lumbosacral sprain.
- The patient underwent four bone marrow concentrate stem cell treatments within 146-day period.
- He experienced a minor improvement after the first treatment, reporting only dull aches with less frequency and stretching his lower back reduced the pain.
- After the third treatment, he reported improved ability to perform daily activities with less pain.
- At the short-term follow-up after the fourth treatment he experienced the most symptomatic relief, reporting a 75% total overall improvement.
- Another follow-up was administered approximately a year and half post-treatment, and his overall improvement increased to 90%. Additionally, his resting pain was 0/10, his active pain was 2/10, and his functionality score increased to 34/40.
These are two documented cases we published in the medical literature. Not every case will have this level of success.
Doctors question spinal stenosis surgery
Many of the patients we see are looking for a an alternative to spinal surgery. Many are deciding between injection treatments whether cortisone injection, epidural injection, PRP or or stm cell injections. For many of these people, they have been told that surgery is the only option because an MRI showed stenosis. For some people surgery is the only answer, as in neurological defect. However, if the patient’s pain is in the lower back, we can have a realistic expectation that our injection treatments can help.
“Symptomatic lumbar spinal stenosis is the most common indication for spinal surgery. However, more than one-third of the patients undergoing surgery for lumbar stenosis report dissatisfaction with the results.”
Despite the fact that many studies insist that surgical treatment is the best option for lumbar spinal stenosis, a startling study was published in the medical journal Spine. (2) In this study, American, Canadian and Italian researchers published their evidence:
“We have very little confidence to conclude whether surgical treatment or a conservative approach is better for lumbar spinal stenosis, and we can provide no new recommendations to guide clinical practice. . . However, it should be noted that the rate of side effects ranged from 10% to 24% in surgical cases, and no side effects were reported for any conservative treatment.”
In the above research it should be pointed out the comparison between lumbar surgery and conservative treatments did not include stem cell therapy. They included the traditional conservative treatments including physical therapy, cortisone injections, pain medications and others listed below.
In 2019, researchers announced the formation of a new study (3) that would test whether conservative care treatment would offer better outcomes than lumbar stenosis surgery. Why? “Symptomatic lumbar spinal stenosis is the most common indication for spinal surgery. However, more than one-third of the patients undergoing surgery for lumbar stenosis report dissatisfaction with the results.”
The MRI’s role in confusing patients
One of the reasons surgery may be no better than conservative care is that the surgery tried to fix a problem that was not there: Pain.
In the medical journal Osteoarthritis and Cartilage,(4) doctors reported that many asymptomatic individuals, those with no pain or other challenges, have radiographic lumbar spinal stenosis. In other words they only have lumbar spinal stenosis on the MRI.
The doctors noted:
- We found that 77.9% of participants had more than moderate central stenosis and 30.4% had severe central stenosis. Only 17.5% of the participants with severe central stenosis were symptomatic.
- They also concluded: Although radiographic lumbar spinal stenosis is common. Symptomatic lumbar spinal stenosis were relatively uncommon in these patients.
I cite more research in my article – My MRI is suggesting back surgery. In one of the studies researchers suggested: “Inappropriate use of MRI leads to increasing interventions and surgeries for low back pain. (The researchers) probed the potential effects of a routine MRI report (how the report was explained to the patient) on the patient’s perception of his spine and functional outcome of treatment.” This helped convince patients that surgery was the only way for them. As demonstrated in this article, it needed not be.
Do steroid injections work? Patients with spinal stenosis seek information on alternatives on epidurals and other injections
A diagnosis of spinal stenosis
A diagnosis of spinal stenosis can be frightening because of the implications that a surgery may be needed to avoid paralysis. It is important to note that in instances where stenosis is so severe that the patient has lost circulation to the legs or bladder control – a surgical consult should be made immediately.
In the December 2017 edition of the medical journal Spine, (5) doctors from the University of Pittsburgh and University Toronto reported these observations in patients seeking non-surgical treatments for lumbar spinal stenosis.
- Three themes related to medical treatment and symptom management arose from analyses –
- (1) an emotional response (depression, anxiety) to lumbar spinal stenosis;
- (2) a desire for education about lumbar spinal stenosis and motivation to pursue education from any available source; and –
- (3) a desire for individualized care based on self-management techniques and lifestyle changes.
- Emotional responses were more evident in individuals receiving medical care, while the other two themes were consistent across all 3 treatment groups.
Individuals with lumbar spinal stenosis may believe misinformation and information from non-medical sources, especially when medical providers do not spend sufficient time explaining the disease process and the reasoning behind treatment strategies. Receiving individualized care focused on self-management led to fewer negative emotions toward care and the disease process. Clinicians should be prepared to address all three of these aspects when providing care to individuals with lumbar spinal stenosis.
Back pain can certainly cause anxiety, depression, and catastrophizing thoughts. The people in this study wanted education and involvement in their choice of treatment. I hope I can provide some for you here in this article.
Epidural injections and Minimally invasive lumbar decompression. Doctors should either just go to the surgery or wait no longer than the failure of the first epidural injection minimally invasive to recommend a more speedy surgery.
Typically, doctors will inject either a steroid to act as an anti-inflammatory to bring down swelling or inflammation or a pain-killer / numbing agent like lidocaine. These treatments are considered to be short-term pain management injection treatments. That is when steroid injections work,
A November 2021 paper (6) presented a summary of a study performed to look at the benefit, if any, of more than one epidural steroid injection in the spine before the mild® Procedure. The mild procedure (minimally invasive lumbar decompression) and epidural steroid injections are both common treatment options for lumbar spinal stenosis. According to the paper the best way to determine how to best treat lumbar spinal stenosis patients, healthcare professionals use a guide to help with the decision-making process (called an algorithm) to pass through non-medical to more invasive therapies that often includes one or more epidural steroid injections and other stenosis steroid injections.
An epidural steroid injection is medication inserted in the lower back to reduce swelling and provide relief from pain. Researchers wanted to look at what changed in the treatment process to a point when the the epidural steroid injections were stopped and a minimally invasive lumbar decompression is carried out. Typically this the point where it would not be in the patient’s best interests to be given more epidural steroid injections. In the study, researchers compared the medical records of participants who had received either just one lumbar epidural steroid or no epidural steroid injection prior to the minimally invasive lumbar decompression, to participants who received two or more epidural steroid injections prior to the minimally invasive lumbar decompression.
Similar outcomes in both treatment groups in this clinical study protocol proved that giving more than one epidural steroid injection prior to the minimally invasive lumbar decompression did not improve how well patients did and may have delayed patient care. Simply, the epidural steroid injections prevented a more productive spinal stenosis treatment from being used. Based on the summary results information of the study, it is recommended that the lumbar stenosis steroid injections standard treatment process for lumbar spinal stenosis patients be changed to offer minimally invasive lumbar decompression either as soon as lumbar spinal stenosis is diagnosed or after the failure of the first epidural steroid injection. It is not suggested to offer multiple epidural steroid injections.
To explore further on this subject I am going to summarize my article Research compares PRP injections to steroid injection for back pain. I invite you to read the whole article for updates and the medical references referred to.
In this article are the basic concepts that epidural steroid injections do not heal pain, they mask pain. Eventually the effectiveness of the epidural steroid injections, if effective at all would wear off. Epidural steroid injections typically provide modest pain relief up to 3 months in patients with lumbosacral radicular pain caused by herniated disks, but they have no impact on spinal stenosis physical disability or incidence of surgery. In fact some researchers consider epidural steroid injections to be, at best, a very short-term painkiller that sometimes prevents a patient from getting the proper treatment for his/her back pain, as suggested in the above research. Further, injections into the epidural space comes with its own risks. Epidural steroid injections have been associated with serious complications, including paralysis and death.
A December 2019 study, (7) also found that use of Epidural steroid injection before surgery offered greater risk of complication in the form of incidental durotomy, damage to the dura mater, the membrane covering the spinal cord.
When epidural steroid injections do not work many physicians will move the patient unto surgery. Procedures will be recommended that will “stabilize the spine” such as spinal fusion, or surgeries or laser methods that will create more space for the nerves by removing bone from the vertebrae.
In a January 2023 paper, (19) doctors evaluated the effectiveness of transforaminal PRP injections in the treatment of radicular pain in patients with lumbar disc herniation.
- Twenty-five patients were enrolled and injected with 4 ml of autologous platelet rich plasma under fluoroscopic guidance via transforaminal epidural injection into area of affected nerve root.
- Patients who received transforaminal injections with autologous PRP showed statistically significant improvements in standard pain, disability and and function scores. The improvements were sustained over twelve-month follow-up and there were no associated complications.
- The researchers concluded: “Transforaminal injection with autologous PRP helps patients relieve chronic pains and be able return to work. Besides, autologous PRP can be considered as a good alternative to epidural steroids in management of lumbar disc herniation.”
Understanding the surgical options for stenosis
In the recommended surgical procedures for spinal stenosis, two choices are the most favored following failed epidural steroid injections.
- A Decompression procedure where the surgeon will shave and cut away the bone narrowing the spinal canals.
- The second, a fusion procedure to limit the movement between two vertebrae and hopefully stop the compression of nerves.
A paper published in October 2017 gives a good outline where conservative medicine is in the treatment of Lumbar stenosis. It is from doctors at the University of South Carolina
- Current literature supporting the inclusion of physical therapy and gabapentin/pregabalin (nerve pain medications) within initial treatments have been positive.
- A recent randomized, double-blinded clinical trial of adding calcitonin (prevents bone breakdown) to epidural steroid injections have shown improvement in pain and function up to 1 year.
- The minimally invasive lumbar decompression (mild) procedure is showing ongoing beneficial results in pain and function.
- Spinal cord stimulation (SCS) may have a role for select patients with lumbar spinal stenosis.
- Finally, the benefits of surgical treatment versus nonsurgical treatment is ultimately inconclusive because of the nature of data collection, inconsistencies.(8)
This is indeed a fair assessment of SOME of the treatment options available to patients. However, not all doctors agree. At New York University in June 2017 research, doctors wrote:
The highest levels of evidence do not support minimally invasive surgery over open surgery for cervical or lumbar disc herniation. However, minimally invasive surgery fusion demonstrates advantages along with higher revision and hospital readmission rates. These results should optimize informed decision-making regarding minimally invasive surgery versus open spine surgery, particularly in the current advertising climate greatly favoring minimally invasive surgery.(9)
Should a patient then seek surgery, minimally invasive or open spine? It is possible that a sham or placebo surgery can deliver the same results?
Researchers at the University of Sydney say that the evidence for recommending lumbar spinal surgery as the best option to patients is lacking and it is possible that a sham or placebo surgery can deliver the same results.(10)
In the research I cited at the top of this article, doctors at the Italian Scientific Spine Institute in Milan wrote: We cannot conclude on the basis of this review whether surgical or nonsurgical treatment is better for individuals with lumbar spinal stenosis. We can however report on the high rate of effects reported in three of five surgical groups and that no side effects were reported for any of the conservative treatment options.(11)
“Considering the majority of these procedures are unnecessarily being performed for degenerative disc disease alone, spine surgeons should be increasingly asked why they are offering these operations to their patients”
A team of Japanese researchers found that patients with lumbar spinal stenosis who do not improve after nonsurgical treatments are typically treated surgically using decompressive surgery and spinal fusion surgery. Unfortunately the researchers could not determine if the surgery had any benefit either.(12) Maybe the patient’s problem was not the stenosis?
The incidence of nerve root injuries following any of the multiple minimally invasive surgical techniques
Now let’s go to another paper that has more of an opinion: From Dr. Nancy Epstein of Winthrop University Hospital:
- “The incidence of nerve root injuries following any of the multiple minimally invasive surgical techniques resulted in more nerve root injuries when compared with open conventional lumbar surgical techniques. Considering the majority of these procedures are unnecessarily being performed for degenerative disc disease alone, spine surgeons should be increasingly asked why they are offering these operations to their patients?”(13)
Surgeons at Leiden University Medical Centre in the Netherlands speculate that doctors go into a diagnosis of lumbar spinal stenosis with the thought that there is osteoarthritis – a bony overgrowth on the spinal nerves. Once determined, the symptoms of patients can be categorized into two groups; regional (low back pain, stiffness, and so on) or radicular (spinal stenosis mainly presenting as neurogenic claudication – nerve inflammation).
In the patients who primarily complain of radiculopathy (radiating leg pain) with an stable spine, a decompression surgery may be recommended to remove bone from around the nerve root to give the nerve root more space. The surgeons warn of the fear that surgery to a stable spine will make it unstable.(14)
A fusion procedure to limit the movement between two vertebrae and hopefully stop the compression of nerves is another option. As mentioned by independent research above – surgery for spinal stenosis should only be considered after conservative therapies have been exhausted. Surgical treatment of lumbar spinal disorders, including fusion, is associated with a substantial risk of intraoperative and perioperative complications,as pointed out in the research by surgeons from Catholic University in Rome.(15)
People still have pain, even after successful surgery.
In the medical journal Public Library of Science one, a November 2019 study (16) from a combined group of 22 medical researchers look at post-surgical patients with degenerative lumbar spinal stenosis from 13 surgical spine centers. The patients were deemed to be good surgical candidates. Following pain and disability testing in the follow up periods post surgery, the researchers concluded that.
“Although most patients experienced important reductions in pain and disability, 29% to 42% of patients were classified as members of an outcome trajectory subgroup that experienced little to no benefit from surgery. These findings may inform appropriate expectation setting for patients and clinicians and highlight the need for better methods of treatment selection for patients with degenerative lumbar spinal stenosis.”
In the video below PRP injections, not, epidural steroid injections are given into the patients lower back area.
Treatment with Bone marrow derived stem cells injections and PRP injections
At the beginning of this article I gave two case histories that were published in a peer-reviewed medical journal. Now I would like to give more of an explanation of bone marrow derived stem cell injection therapy and also provide information about Platelet Rich Plasma injections.
Spinal stenosis is the result of bone growth in the spine. The bone growth is occurring because the bone is trying to stabilize the spine from excessive movement or laxity, a state of vertebrae slipping out of place. Fusion surgery is recommended as a means to stop the bone spur growth and vertebrae instability by quickly replacing the slow natural fusion with a rapid surgical fusion.
Regenerative medicine including PRP injections and Stem Cell Therapy injections (watch the video below) work in a completely different way than epidural steroid injections. These injection treatments stabilize the spine by strengthening the often forgotten and underappreciated spinal ligaments and tendons. These injection techniques help stabilize the spine, which is imperative as unstable joints can lead to – or further exacerbate – the arthritis that causes spinal stenosis.
In the medical journal Insights into imaging, researchers wrote of the four factors associated with the degenerative changes of the spine that cause spinal canal stenosis:
- disc herniation.
- hypertrophic facet joint osteoarthritis, (an overgrowth of bone)
- ligamentum flavum hypertrophy (inflammation of the spine’s supporting ligaments – the ligamentum flavum).
- and spondylolisthesis (stress fractures causing the vertebrae to slip out of place)
The same research suggests that these conditions can prevent the formation of new tissue (collagen) which can initiate repair.(17)
Collagen is of course the elastic material of skin and ligaments. Here the association between collagen interruption and spinal stenosis can be made to show spinal instability can be THE problem of symptomatic stenosis.
In the above video Dr. Marc Darrow describes bone marrow stem cell injections.
A study on what damaged spinal ligaments can do
A study in the Asian Spine Journal investigated the relationship between ligamentum flavum thickening and lumbar segmental instability, disc degeneration, and facet joint osteoarthritis. Ligament thickening is the result of chronic inflammation. Chronic ligament inflammation is the result of a ligament injury that is not healing.
What these researchers found was a significant correlation between ligamentum flavum thickness, spinal instability and disc degeneration. More so, the worse the degenerative disc disease, the worse the ligamentum flavum thickness.(18)
PRP injections and stem cells address the problem of ligament damage and instability that epidural steroid injections do not. While injections of epidural steroid addresses inflammation, they do not rebuild damaged tissue. Addressing these problems address the problems of spinal instability. Addressing the problems of spinal instability can address the problems of spinal and cervical stenosis.
1 Darrow M, Shaw BS. Treatment of Lower Back Pain with Bone Marrow Concentrate. Biomed J Sci&Tech Res 7(2)-2018. BJSTR. MS.ID.001461. DOI: 10.26717/ BJSTR.2018.07.001461.
2 Pazarlis K, Punga A, Schizas N, Sandén B, Michaëlsson K, Försth P. Study protocol for a randomised controlled trial with clinical, neurophysiological, laboratory and radiological outcome for surgical versus non-surgical treatment for lumbar spinal stenosis: the Uppsala Spinal Stenosis Trial (UppSten). BMJ Open. 2019 Aug 20;9(8):e030578. doi: 10.1136/bmjopen-2019-030578. PMID: 31434781; PMCID: PMC6707759.
3 Zaina F, Tomkins‐Lane C, Carragee E, Negrini S. Surgical versus non‐surgical treatment for lumbar spinal stenosis. The Cochrane Library. 2016 Jul 1.
4 Lynch AD, Bove AM, Ammendolia C, Schneider M. Individuals with lumbar spinal stenosis seek education and care focused on self-management–results of focus groups among participants enrolled in a randomized controlled trial. The Spine Journal. 2017 Dec 12
5 Ishimoto Y, Yoshimura N, Muraki S, Yamada H, Nagata K, Hashizume H, Takiguchi N, Minamide A, Oka H, Kawaguchi H, Nakamura K. Associations between radiographic lumbar spinal stenosis and clinical symptoms in the general population: the Wakayama Spine Study. Osteoarthritis and cartilage. 2013 Jun 1;21(6):783-8.
6 Pryzbylkowski P, Bux A, Chandwani K, Khemlani V, Puri S, Rosenberg J, Sukumaran H. Understanding whether chronic lower back pain patients with lumbar spinal stenosis benefit from multiple epidural steroid injections prior to the mild® Procedure. Pain Management. 2021 Aug(0).
7 Labaran LA, Puvanesarajah V, Rao SS, Chen D, Shen FH, Jain A, Hassanzadeh H. Recent Preoperative Lumbar Epidural Steroid Injection Is an Independent Risk Factor for Incidental Durotomy During Lumbar Discectomy. Global Spine Journal. 2019 Dec;9(8):807-12.
8 Patel J, Osburn I, Wanaselja A, Nobles R. Optimal treatment for lumbar spinal stenosis: an update. Current Opinion in Anesthesiology. 2017 Oct 1;30(5):598-603.
9 Vazan M, Gempt J, Meyer B, Buchmann N, Ryang YM. Minimally invasive transforaminal lumbar interbody fusion versus open transforaminal lumbar interbody fusion: a technical description and review of the literature. Acta Neurochir (Wien). 2017 Jun;159(6):1137-1146
10 Machado GC, Ferreira PH, Yoo RI, et al. Surgical options for lumbar spinal stenosis. Cochrane Database Syst Rev. 2016 Nov 1;11:CD012421.
11 Zaina F, Tomkins-Lane C, Carragee E, Negrini S. Surgical Versus Nonsurgical Treatment for Lumbar Spinal Stenosis. Spine (Phila Pa 1976). 2016 Jul 15;41(14):E857-68.
12 Inoue G, Miyagi M, Takaso M. Surgical and nonsurgical treatments for lumbar spinal stenosis. Eur J Orthop Surg Traumatol. 2016 Oct;26(7):695-704. doi: 10.1007/s00590-016-1818-3. Epub 2016 Jul 25.
13 Epstein NE. More nerve root injuries occur with minimally invasive lumbar surgery: Let’s tell someone. Surg Neurol Int. 2016 Jan 25;7(Suppl 3):S96-S101. doi: 10.4103/2152-7806.174896. eCollection 2016.
14 Overdevest GM, Moojen WA, Arts MP, Vleggeert-Lankamp CL, Jacobs WC, Peul WC. Management of lumbar spinal stenosis: a survey among Dutch spine surgeons. Acta Neurochir (Wien). 2014 Aug 7.
15 Proietti L, Scaramuzzo L, Schiro’ GR, Sessa S, Logroscino CA. Complications in lumbar spine surgery: A retrospective analysis. Indian J Orthop. 2013 Jul;47(4):340-5. doi: 10.4103/0019-5413.114909.
16 Hebert JJ, Abraham E, Wedderkopp N, Bigney E, Richardson E, Darling M, Hall H, Fisher CG, Rampersaud YR, Thomas KC, Jacobs B. Patients undergoing surgery for lumbar spinal stenosis experience unique courses of pain and disability: A group-based trajectory analysis. PloS one. 2019;14(11):e0224200-.
17 Kushchayev SV, Glushko T, Jarraya M, et al. ABCs of the degenerative spine. Insights into Imaging. 2018;9(2):253-274. doi:10.1007/s13244-017-0584-z.
18 Yoshiiwa T, Miyazaki M, Notani N, Ishihara T, Kawano M, Tsumura H. Analysis of the Relationship between Ligamentum Flavum Thickening and Lumbar Segmental Instability, Disc Degeneration, and Facet Joint Osteoarthritis in Lumbar Spinal Stenosis. Asian Spine Journal. 2016;10(6):1132-1140. doi:10.4184/asj.2016.10.6.1132. —
19 Le VT, Dao LT, Nguyen AM. Transforaminal injection with autologous platelet-rich plasma in lumbar disc herniation: A single-center prospective study in Vietnam.