FUNCTIONAL OUTCOMES AFTER LUMBAR MICRODISCECTOMY FOR LUMBAR DISC HERNIATION: A SINGLE-CENTER EXPERIENCE

Lumbar disc herniation (LDH) is one of the most prevalent spinal afflictions in adults and is a significant contributor to low back pain and sciatica in the world. It is mainly caused by disc degeneration with a nucleus pulposus protruding or extruding through the annulus fibrosus. The displaced disc material can press on neighbouring nerve roots, creating pain in the radiating leg, sensory disturbances, motor weakness, and functional disability. It is a condition that mainly occurs in the third to fifth decades of life and has an important socio-economic dimension, due to loss of productivity, health costs, and lower quality of life [1,2].It is estimated that 1–3% of the general adult population has symptomatic lumbar disc herniation and that L4–L5 and L5–S1 are the most commonly affected spinal levels due to the greater biomechanical stress. While about 10-20% of patients will improve with conservative measures such as analgesics, physical therapy, activity modification, and epidural steroid injections, others will still have persistent radicular pain or progressive neurologic deficits that require surgical treatment [3]. Lumbar Microdiscectomy has emerged as the "gold standard" surgical approach to the treatment of symptomatic, conservative-refractory lumbar disc herniation. Microdiscectomy is now widely used in place of the traditional open discectomy due to the exceptional visualisation and the low soft tissue damage that it causes. With the use of an operating microscope and microsurgical technique, the removal of the herniated disc fragments can be achieved with a shorter incision and limited muscle dissection for accurate removal. Thus, patients have less pain after surgery, a shorter hospital stay, are mobilized earlier, and return to a normal lifestyle sooner [4,5]. Lumbar microdiscectomy has been proven to provide fast relief of radicular pain and significant improvement in neurological function in several studies. Quality of postoperative recovery is often expressed using patient-reported outcome measures, including a pain Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI). The majority of patients improve in pain and disability in the first few months after surgery. The extent of functional recovery, however, depends on patient characteristics, length of symptoms, age, body mass index, smoking, work demands, psychological factors, and preoperative neurologic impairment [6,7].While the recovery rate of a lumbar microdiscectomy is over 80% for the right patient, some complications can hurt recovery, including recurrent herniation, dural tear, wound infection, nerve root injury, epidural fibrosis, and chronic pain. Thus, proper patient selection, precise surgical procedures, and rehabilitation are key to achieving optimal function and minimizing complications [8].Although lumbar microdiscectomy has been studied in many studies worldwide, outcome data from a single centre in developing countries are relatively small. There may be variations in healthcare facilities, patient age, availability of surgical intervention, and rehabilitation, resulting in variations in postoperative recovery. Thus, it is important to assess the outcomes of the institutions for benchmarking of surgical performance and enhancing clinical practice [9]. A retrospective analysis was done in the present study to evaluate the functional results of lumbar microdiscectomy in patients with a symptomatic lumbar disc herniation treated in a tertiary care hospital. The functional improvement was assessed with validated clinical outcome scales, and demographic and clinical variables related to the recovery after surgery were also analyzed. Results of this study are anticipated to yield valuable knowledge about the efficacy and safety of lumbar microdiscectomy in the actual clinical setting and help optimize patient selection and post-operative care [10].

 Study Objectives

To assess improvement in functional outcomes following lumbar microdiscectomy for lumbar disc herniation and identify demographic and clinical variables that are associated with this improvement in pain, disability, neurological status, and functional status.

A total of 100 patients underwent lumbar microdiscectomy during the study period. There were 62 (62%) males and 38 (38%) females, with a mean age of 44.8 ± 11.2 years. The majority of patients belonged to the 31–50-year age group. The L4–L5 intervertebral level was involved in 54% of patients, followed by L5–S1 in 36%, while 10% had herniation at L3–L4. The mean preoperative VAS pain score was 8.2 ± 1.1, which significantly improved to 2.1 ± 1.3 at six months after surgery (p<0.001). Likewise, the mean Oswestry Disability Index improved from 56.4 ± 12.7 preoperatively to 18.9 ± 9.3 postoperatively (p<0.001). Eighty-seven patients achieved excellent or good functional recovery, whereas thirteen demonstrated fair or poor outcomes. Patients younger than 50 years showed significantly greater improvement in functional status than older patients (p=0.028). Patients with symptom duration below six months experienced better recovery compared with those having prolonged symptoms (p=0.015). Gender was not significantly associated with postoperative outcomes (p=0.482). Postoperative complications occurred in six patients, including superficial wound infection (3%), incidental dural tear (2%), and recurrent lumbar disc herniation requiring revision surgery (1%). No mortality or permanent neurological deterioration was observed.

 Table 1. Baseline Demographic and Clinical Characteristics of the Study Population (n = 100)

Values are presented as frequency (n), percentage (%), or mean ± standard deviation (SD).

Table 2. Comparison of Preoperative and Postoperative Functional Outcomes

Functional outcomes were assessed using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI). Statistical significance was set at p<0.05.

 Table 3. Factors Associated with Good Functional Recovery After Lumbar Microdiscectomy

Good functional recovery was defined as excellent or good postoperative outcome based on clinical assessment and ODI improvement.

Table 4. Postoperative Complications Following Lumbar Microdiscectomy

Overall postoperative complication rate was 6%. Most complications were managed successfully without permanent neurological deficits.

A single-center, retrospective analysis was performed on the functional outcome of lumbar microdiscectomy in 100 patients with symptomatic lumbar disc herniation. The results showed a substantial reduction in pain intensity and functional disability, and 87% of patients had a good to excellent postoperative outcome. In addition, patient age was inversely correlated with good functional recovery, while sex was not. Duration of symptoms was also significantly correlated with the outcome of surgery. The results confirm the efficacy and safety of lumbar microdiscectomy for the right candidates [11,12]. The demographic data of our study were similar to what has been recently reported in the literature. The mean age of 44.8 ± 11.2 years and the majority of patients were male (62%) were similar to the conclusions of the studies performed in the last five years, which reported that the mean age of the patients with lumbar disc herniation was 45 to 46 years, and the majority of patients were male [13,14]. As in previous studies, the L4–L5 level was the most frequently affected disc level compared to the L5–S1 level, which is most subjected to biomechanical stress [15]. Perhaps the most important result of this study was the large reduction in postoperative pain and disability scores. After 6 months of follow-up, the mean VAS score dropped from 8.2 to 2.1, and the mean Oswestry Disability Index (ODI) increased to 18.9 from 56.4. These enhancements are consistent with recent prospective and retrospective studies, which have shown  significant pain and disability improvement after lumbar microdiscectomy. This is consistent with the results of large multicenter studies, which have shown that over 80% of patients have clinically significant improvements in pain and function at 1 year after surgery [16,17]. The success rate in our series was 87%, which is similar to the success rate reported by recent studies after lumbar microdiscectomy [16–18]. These consistently high success rates are due to the ongoing improvements in microsurgical techniques, patient selection, and perioperative care, as well as the setup of rehabilitation protocols that can be followed. Our study found a relatively low rate of complications (6%), which is consistent with recent systematic reviews that found complication rates kept below 10% with superficial wound infections, incidental dural tears, and recurrent disc herniation being the most common adverse events [18,19].One of the key findings of this study was that there was a significantly greater functional recovery for younger patients compared with older patients. This is corroborated by recent studies indicating that younger patients have decreased degenerative spinal processes, increased postoperative rehabilitation potential, and increased regenerative capacity. Similarly, patients who had symptoms for less than 6 months had a better outcome after surgery than those with more than 6 months of symptoms. If there is a delay in surgical treatment, chronic compression of the nerve root and permanent nerve injury may develop, leaving a poor chance of full recovery of function. Recent cohort studies have also found similar results, with a focus on the advantages of early surgical intervention following failure of conservative treatment [20-21]. In this study, a correlation between patient gender and postoperative recovery was not significant. This result is consistent with a few recent studies that showed that patients of both sexes are benefiting from lumbar microdiscectomy in a similar way when performed based on the accepted surgical indications [22]. From these observations, it would seem that demographic factors should not really be considered in surgical management decisions. There are a few limitations to the results of this study. Because of the retrospective design of the study and the single center, there is a possibility of selection bias and incomplete documentation. The number of patients in the study was small, and the functional outcomes were evaluated only at 6 months after surgery. Furthermore, other factors that could affect long-term outcomes, such as smoking status, occupation requirements, psychological status, and body mass index, were not assessed. The results of these studies need to be confirmed with longer follow-up and larger sample sizes in multicenter prospective studies in order to establish other predictors of postoperative success [23]. In general, the present study shows that lumbar microdiscectomy is an excellent pain relief procedure, which leads to significant improvements in functional parameters, and has a low complication rate in patients suffering from lumbar disc herniation. The results are congruent with current knowledge and add to the body of evidence indicating that lumbar microdiscectomy is the preferred surgical procedure for a well-selected patient population who have not responded to conservative management.

 Limitations

The limitations of this study are that it is retrospective, was conducted in a single center, and the sample size is relatively small, the findings may not be generalizable. Long-term results were not possible due to the short follow-up. The follow-up was too short to assess recurrent or late complications. Further multicenter studies with longer follow-up are indicated.

Lumbar microdiscectomy is a safe and effective surgical procedure for lumbar disc herniation, which relieves pain and improves function and has a low incidence of complications. Better postoperative outcomes were related to earlier surgical intervention and younger age. This Study confirms the use of lumbar microdiscectomy in the proper patients.

 Disclaimer: Nil

Conflict of Interest: Nil

Funding Disclosure: Nil

Authors Contributions

Concept & Design of Study: Baynazir khan

Drafting: attiya nasir,

Data Collection & Data Analysis:faiz alam, saad sultan      

Critical Review: Baynazir khan

Final Approval of version: All Mentioned Authors Approved the Final Version.

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