Research Review By Dr. Robert Rodine©

Date Posted:

April 2010

Study Title:

A review of current treatment for lumbar disc herniation in children and adolescents

Authors:

Dang L & Liu Z

Author Affiliations:

Orthopedic Department, Peking University Third Hospital, China.

Publication Information:

European Spine Journal 2010; 19: 205-214.

Background Information:

The lifetime prevalence of lumbar disc herniation (LDH) is 40% in adults (1). Based on recent literature, we also know that close to 50% of asymptomatic patients have some form of disc pathology demonstrated on special imaging (2). Therefore, we must approach this condition with caution. Additionally, previous research has found that 85% of all back pain results from a non-specific cause, meaning due to a cause other than lumbar disc herniation (3).

The frequency of LDH in children and adolescents is less than that seen in adults, and overall this topic has received less research attention. However, a Finnish study of over 12,000 babies followed for almost 30 years for symptoms of back pain revealed that no subjects were hospitalized prior to the age of 15 years for LDH. However, at 20 yrs of age 0.1-0.2% of subjects had been hospitalized for LDH. This number had increased further to 9.5% at 28 years of age for males and 4.2% for females (4).

As a result of its rarity, there is limited research available to direct clinicians in the management of LDH in children and adolescents. The aim of this paper was to review the existing evidence on the management of LDH in this patient group.

Literature Reviewed:

While the search strategy detailed no timeline, retrieved and included studies ranged in publication date from 1945 to 2008.

In total, 55 case series and 8 single-case studies were identified which included a total of 1963 cases of surgically/intradiscally treated patients. Following exclusions, 44 case series and 8 single-case studies remained, including data on 1664 patient cases.

All trials involved surgical intervention, with no included studies pertaining directly to manual therapy. That being said, there are some relevant points that practitioners can keep in mind.

Pertinent Points Include:
  • Identified literature points to trauma as being the most common inciting event leading to LDH in a younger population, with 30-60% of hospitalized patients noting a history of trauma.
  • Genetics was the 2nd most common predisposing factor towards LDH, as 13-57% of hospitalized patients had first-degree relatives who also suffered from the condition.
  • While vertebral anomalies are considered to be related to adolescent LDH, its direct influence has not been measured as a general group. Epiphyseal ring separation however has been noted concurrently in up to 40% of cases.
  • Clinical presentation of LDH in children and adolescents is similar to that of adults, however children are less likely to present with neurological symptoms. As children tend to have greater nerve root tension than adults, a positive straight leg raise is noted in 90% of patients.
Conservative Therapy for LDH in Children/Adolescents:

Conservative treatment noted within this manuscript is limited to bed rest, activity limitation, generically labeled physical therapy, NSAIDs and analgesics. Despite what we know of its influence in the adult population, bed rest is recommended for 1-2 weeks in patients with severe pain, followed by bracing for a similar period. Representing a major flaw of this manuscript, conservative therapy is presented as one generic group, despite its heterogeneity. No descriptions are provided on what physical therapy might employ, or its individual success rate.

The authors note that the success rate for conservative therapy in this patient population ranges from 25-50% in those without neurological symptoms and simply states that it ‘has been widely agreed upon by most authors that conservative therapy is not as effective for pediatric LDH as it is for adults.’ (Note that the authors here referred to pediatric patients, rather than children or adolescents).

As no other information is provided for the other two age groups, it is unclear if this is simply a generalization towards all those under the age of 21, or specifically to a pediatric population. Regardless, the data is incomplete and over-generalized as potential positive effects of physical/manual therapies are grouped together with the potential negative effects of 1-2 weeks of bed rest.

The authors did review a rationale for why conservative therapy for LDH in this population may fail as compared within an adult population. Primarily, as the nucleus is more hydrated in younger individuals, it is less likely to dehydrate and become reabsorbed by the immune system. Also, as trauma is a more common inciting event, the severity of rupture within the annulus may be greater. As the epiphyseal rings are not fully formed, trauma that results in separation may create additional structural problems. Most surprisingly, the authors note that children and adolescents are less likely to adhere to bed rest, predisposing them to poor recovery.

Surgical Considerations:

The authors reviewed several options and techniques.

Intradiscal therapy:

Chemonucleolysis is the only reported intradiscal technique being utilized in this patient population. As it is associated with less surgical trauma, less post-operative scarring, shorter in-hospital stay and earlier re-entry to mobility, this technique is considered advantageous.

It is proposed that those with more severe leg pain, limited SLR, and CT confirmation of disc lesion are indicated for this technique. Success rate is noted as 80-89% in the short term (<5 years) and 64% in the intermediate term (5-10 years). Failure rate is estimated at 11-26% of patients, who will eventually require surgery. The major disadvantage of this procedure versus more aggressive surgery is the limited ability to remove nuclear material, and decompress effected nerve roots.

More advanced surgery can involve a percutaneous endoscopic discectomy (PED), open discectomy, which can range from an open discectomy with or without laminectomy or a microdiscectomy, or fusion. The indications for such procedures are severe pain subsequent to at least 4-6 weeks of conservative therapy, affected ADL’s, progressive neurological deficit and/or associated spinal deformities.

Percutaneous endoscopic discectomy:

This procedure is associated with a 93-100% short term success rate, when complications are not encountered. As with the previous surgical indications, PED is indicated with an intact disc or when a protruded/extruded disc still remains subligamentous.

Discectomy:

Discectomy is used when more decompression is required. However, as a result of the greater surgical insult to the surrounding soft-tissues compared to PED the rate of post-operative pain increases. Additionally, there is an increased risk of nerve damage from the procedure. The success rate of discectomy ranges from 79-100% short-term, 65-100% in the intermediate and 67-100% in the long-term.

With regards to open discectomy (the most common surgical procedure for LDH in children and adolescents), partial laminectomies are conducted with a posterolateral herniation and semilaminotomy/full laminectomies are performed with central herniations. Microdiscectomy has recently shown success rates of 98-100% for the short-term in pediatric populations, dropping only to 92% for the intermediate term and 85% for the long term (>10 years).

With respect to long-term outcome however, the probability of requiring a subsequent operation with discectomy for LDH was found to be 80% at 10 years and 74% at 20 years.

Fusion:

This technique is reported infrequently within the literature in the pediatric population, which is in unison with the most common opinion of included authors that this surgery should not be performed in this population. Indications for fusion however are aimed at restoring stability and include a clear indication of instability and/or spondylolisthesis, ‘incompetent’ facet joints or in cases whereby multiple laminectomies are being performed.

Post-operative complications typically surround the risk of infection or hematoma’s. However, with discectomy there is a risk of narrowed disc space, foraminal stenosis and adjacent disc degeneration.

Clinical Application & Conclusions:

It is evident from this review that research into conservative care for LDH in children and adolescents is required. For now, no firm clinical recommendations can be made with respect to the optimal treatment approach.

Study Methods:

PUBMED and EMBASE databases were searched using MeSH terms relating to disc herniations in children and adolescent patients with relation to treatment. Retrieved articles were hand-searched for additional references.

Retrieved articles were grouped according to the outcome attained, with success-rate being described as the rate of cases attaining a good and/or excellent outcome. This related to patients experiencing no/mild pain, returning to normal ADL’s and stating satisfaction with treatment.

Cases were excluded if the patient age was 21 years or greater or if detailed outcome summaries were not included.

Study Strengths / Weaknesses:

The study design is the strongest limitation of this manuscript. While the authors detailed the search strategy used, databases and search terms utilized and inclusion/exclusion criteria, this is by no means a systematic review. Strength of the study would be increased if the authors identified how they reached a consensus upon disagreements, the rate of agreement between reviewers and a quality assessment measure of the studies included/excluded.

Additionally, the manuscript is clearly geared towards medical practitioners, providing a detailed summary on surgical procedures and their success rates. More importantly, the utilized search strategy and inclusion/exclusion criteria do not specify that the review will only be reviewing surgical cases, however only identifies surgical cases. Subsequent to this, conservative care is reviewed within the discussion and heavily referenced, with no indication as to where this information came from based on the search results listed.

Conservative therapy is considered to be bed rest, NSAID’s, activity limitation, analgesics and physical therapy. No details on the individual effectiveness of these therapies are offered, nor on the characteristics of physical therapies provided within included literature, nor guidance on what to attempt/avoid. This being said, we must not take for granted the scarceness of manual medicine literature within this clinical area, which reveals an obvious possibility for future research within manual therapy.

Additional References:

  1. Frymoyer et al. Risk factors in low back pain. An epidemiological survey. JBJS 1983; 65: 213-218.
  2. Kanayama et al. Cross-sectional magnetic resonance imaging study of lumbar disc degeneration in 200 healthy individuals. J Neurosurg Spine 2009; 11(4): 501-7.
  3. Deyo et al. What can the history and physical examination tell us about low back pain? JAMA 1992; 268(6):760-5.
  4. Zitting et al. Cumulative incidence of lumbar disc diseases leading to hospitalization up to the age of 28 years. Spine 1983; 2337-2343