Results of Mini-open Discectomy According to Sagittal Profile
Condition: Displacement of Intervertebral Disc Without Myelopathy
MeSH terms: Intervertebral Disc Displacement; Spinal Cord Diseases
Study type: Observational

Summary: 
      In the normal healthy population, the sagittal alignment can be divided into four types based
      on the size of the sacral slope and lumbar lordosis. The effect of this sagittal profile
      especially type 2 with almost straight lordosis on the clinical outcomes of patients after
      mini-open discectomy is unknown. In this study, the results of patients who underwent
      mini-open discectomy were evaluated according to sagittal profile types of the patients.
    

Detailed description: 
      Lumbar disc herniation (LDH) is the most common cause of sciatica and when conservative
      treatment fails or there is progressive neurological deficit, surgical excision of the
      herniated nucleosus pulposus is standard of care. Although minimally invasive methods such as
      endoscopic discectomy have been tried to be popular in recent years, open lumbar discectomy
      is still successfully performed in lumbar disc herniations due to some drawbacks of
      endoscopic techniques such as having long learning curve, higher radiation exposure to the
      surgeon, similar long-term results or the deception of commercial enterprises about
      endoscopic techniques and the pressure placed on surgeons in this direction.

      Herniation of the nucleus pulposus as a result of massive LDH will inevitably result in
      disruption of normal lumbar biomechanics. Moreover, it has been shown that the healing
      process of the posterolateral herniation, which is biologically the weakest part of the
      posterior longitudinal ligament, will cause disc degeneration as a result of the repair and
      inflammation process in the annulus. However, the same authors claimed that, unlike the
      process in discogenic low back pain, macrophages in herniated discs can act to remove free
      pulposus fragments. There are few studies in the literature about the long-term consequences
      of this degeneration, which the investigators can consider as an accelerated aging process.
      Although clinically very successful results are obtained in the early postoperative period,
      it has been reported that the long-term success after discectomy may decrease from 90% to 60%
      over time. Depression or somatization, strenuous job and recurrent disc herniation or
      degeneration have been shown to cause long-term regression of results. In a prospective
      cohort study the authors reported a similar or worse leg pain rate in 30% of patients at the
      end of 10 years. In a study investigating reoperation after open lumbar discectomy, it was
      reported that the estimated rate of reoperation reached almost 45% at the end of 30 years.

      In an extraordinary review evaluating the spinopelvic organization and the pathological
      adaptation to it, the mechanical stress, especially increased by hypolordosis, would cause
      the degenerative process in the spine to progress more rapidly. The basic theories explaining
      this are that the contact force, which is defined as the resultant force of the system
      created by gravity and abdominal pressure from the front and the dense paraspinal muscle mass
      from the posterior, mainly targets the discs. However, studies evaluating spinopelvic
      orientation in patients with LDH are limited. In a case-control study investigating the
      relationship between sciatica and spinopelvic harmony, more vertical sacrum, anterior C7
      plumb line and hypolordosis were found in the LDH group. In a study examining the etiology
      and mechanism of sagittal imbalance caused by LDH, lumbar lordosis improved almost twice
      after endoscopic discectomy and LDH is probably one of the causes of compensatory sagittal
      imbalance.

      Although there are studies on the pathogenesis and mechanics of LDH's etiology and
      post-discectomy results, the effect of the generally accepted normal lordosis types described
      by Roussouly P. on the degenerative process and patient scores after open standard discectomy
      is unknown. Therefore, in this study, the investigators aimed to compare the clinical results
      of patients with hypolordotic Type 2 and other types after open discectomy. Our hypothesis is
      that the mid-term clinical scores will be worse in Roussouly Type 2 patients with less
      lordosis.
    

Intervention name(s): lumbar discectomy
Intervention type(s): Procedure
Intervention description(s): mini-open discectomy
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Adult patients with lumbar disc herniation who are candidates for surgical treatment
      
Keywords: intervertebral disc displacement, spinal curvatures, Outcome