Lumbar revision microdiscectomy in patients with recurrent lumbar disc herniation: A single-center prospective series.

BACKGROUND: Recurrent lumbar disc herniation (RLDH) is a common complication following primary microdiscectomy. Notably, revision surgery for recurrent disc herniation typically warrants "aggressive discectomy (AD)" rather than microdiscectomy due to the marked changes in anatomy, including postoperative scar. Here, we prospectively evaluated clinical outcomes of 22 RLDH patients following secondary aggressive discectomy (AD).
METHODS: Records of 15 males and seven females averaging 41.7 years of age (range 21-60) who developed RLDH following primary microdiscectomy at the L4-5 (n = 12) and L5-S1 (n = 10) levels were studied. All patients underwent secondary AD for recurrent lesions (2014-2019). Multiple clinical parameters were assessed for these 22 patients. Outcomes were evaluated an average of 28.8 months postoperatively and included assessment of visual analog scales (VASs) and Japanese Orthopedic Association (JOA) Scores.
RESULTS: The VAS scores for back and radicular pain significantly improved, as did the JOA scores following surgery in all 22 patients after secondary AD.
CONCLUSION: The authors concluded that secondary conventional revision discectomy (e.g., AD) effectively and safely managed RLDH. Copyright:

INTRODUCTION

Recurrent lumbar disc herniation (RLDH) following initial microdiscectomy is the most common cause for reoperations.[7] Notably, revision for RLDH is more complex and challenging, thus typically warranting increased exposure offered by more “open” aggressive discectomy (AD). This study evaluated the risk factors for RLDH and clinical outcomes for 22 patients who originally underwent lumbar microdiscectomy followed by secondary AD for RLDH.

MATERIALS AND METHODS

With IRB approval, we prospectively studied outcomes for 22 patients who originally underwent microdiscectomies, but secondarily whose RLDH were managed with 19 AD versus 2 simple excisions of extruded fragments (2014 and 2019) [Table 1]. Patients all underwent X-ray and MR studies to define RLDH. Outcome criteria included: the visual analog scale (VAS; low back/radicular pain) and the Japanese Orthopedic Association (JOA) Scores.[2] Nineteen primary operations were performed by a single surgeon, while three were transferred from other institutions [Figure 1]. Clinical demographic data, the average follow-up duration (28.8 mos.: range 24-70), and level of RLDH were studied (e.g., L4-5 [12 patients; 54.54%] and L5-S1 levels [10 patients; 45.45%]) [Table 2].

Table 1:

Inclusion and exclusion criteria.

Figure 1:

Primary discectomy done on January 11, 2014 at L 4-5 level of 46-year-old man. (a) Dynamic X-ray shows no instability (b), and (c,d) sagittal and axial view of T2W magnetic resonance imaging shows disc herniation.

Table 2:

Demographic profile of the patients with revision discectomy in RLDH (n=22).

Statistical analysis

The quantitative data were analyzed statistically using Statistical Package for the Social Science, version 25, Armonk, NY, IBM Corp.

RESULTS

The operative time for secondary AD was 95.0 ± 9.0 min (range 65–125 min), the mean blood loss 85 ml (range, 70–150 ml), and average postoperative hospital stay was 5 days (range, 4–8 day). The mean VASs and JOA scores were significantly improved postoperatively [Tables 3 and 4]. Surgical results were excellent in 6 (27.27%), good in 14 (63.64%), and fair in 2 (9.09%) patients. The JOA mean recovery score was 88.8 (±32.25), while the average satisfactory JOA rate was 86.36%. Six (27.27%) patients developed postoperative complications: dural tear (one patient), superficial wound infection (two patients), transient neurological deficit (one patient), postoperative instability (one patient), and additional recurrent herniation (one patient).

Table 3:

Clinical outcomes of patients with revision discectomy in RLDH (n=22).

Table 4:

Clinical outcomes of patients with revision discectomy in RLDH (n=22).

DISCUSSION

Surgical options for RLDH

The main two surgical options for RLDH include revision lumbar discectomy (e.g., repeat microdiscectomy vs. AD) [Figure 2] and/ or instrumented fusion. Notably, however, revision surgery is much more difficult than primary surgery due to perineural scarring.[2] Although recent papers document that both approaches may be equally efficacious for RLDH cases, AD exposures offer better visualization and lesser rate of complications (e.g., CSF leaks, infection, retained disc, and reoperation), including instability (e.g., more restricted bony exposure).[4]

Figure 2:

Revision discectomy is done of the same patient on February 20, 2018 after 4 years. (a-d) shows recurrence disc herniation in sagittal and axial magnetic resonance imaging in T2W image, (e) and (f) preoperative dynamic X-ray in lateral position showing no instability.

Timing of redo surgery

The typical pain-free interval between the index microdiscectomy and the RLDH is typically 6 months.[1,7] With MR, establishing the diagnosis of an RLDH within these six postoperative months may be difficult due to postoperative scarring. Various risk factors have reportedly been associated with RLDH, including (1) older age/male sex, (2) occupation (e.g., heavy labor), (3) elevated BMI, and (4) more severe Modic changes.[5,7] The higher risk of recurrence in older patients is believed to be attributable to the greater disc degeneration in these patients.[4] Heavy laborers, heavy weight lifters, the lack of regular physical exercise, low body mass index (BMI), higher BMI, and obesity (BMI ≥30 kg/m2) were all significant predictors for reoperations.[3,5,6]

CONCLUSION

The management of the RLDH requires following original microdiscectomy that warrants AD for better visualization and safer operative dissection (e.g., to more readily deal with postoperative scar formation).