Successful Return to Elite Competition following a Foraminal Block for Minimal Far-lateral Disc Herniation at L5-S1: A Report of 2 Cases

Takayuki KITAHARA; Yuji NAGAO; Naoto ONO; Takafumi OHSHIMA; Saori SOEDA; Kosuke SUGIURA; Masatoshi MORIMOTO; Hiroaki MANABE; Fumitake TEZUKA; Hiroshi KAGEYAMA; Junzo FUJITANI; Kazuta YAMASHITA; Koichi SAIRYO

doi:10.2176/jns-nmc.2025-0287

Abstract

This report presents 2 cases demonstrating how a foraminal block served as both a diagnostic tool and an effective treatment for small far-lateral lumbar disc herniation at L5-S1 in elite athletes. The patients were a male swimmer in his early 20s and a female figure skater in her late teens, both of whom developed activity-related low back pain, with symptoms acutely exacerbated by the high flexion and extension loads inherent to their sports, which compromised their ability to compete at the highest level. A fluoroscopy-guided foraminal block was performed in each case; the key technical component was careful paraneural needle placement, stopping just short of the nerve root to minimize the risk of iatrogenic injury while targeting the inflammatory environment throughout the foramen. The diagnosis was confirmed in both athletes by reproducing their specific pain during injection. This non-operative intervention provided pain relief that was sufficient for successful participation in a major international competition in one case and continuation of a critical qualifying season for a premier global event in the other. This approach represents a critical diagnostic and therapeutic strategy that can avoid the need for surgery and preserve an elite athlete's immediate career goals.

Introduction

Low back pain is a common problem in elite athletes and can disrupt training and compromise competitive performance.¹^,²⁾ Among the various etiologies, far-lateral lumbar disc herniation (FLLDH) represents a clinical challenge, often requiring specific surgical considerations to achieve satisfactory outcomes.³⁾ Failure to recognize this condition can lead to persistent symptoms and unsatisfactory outcomes after treatment.⁴⁾ FLLDH often results in severe radicular pain, which can be more intense than that associated with typical intraspinal herniations because of direct compression of the dorsal root ganglion.⁵⁾

For elite athletes, linking low back pain to specific imaging findings is particularly challenging, given the reported poor association between magnetic resonance imaging (MRI) abnormalities and symptoms in this group⁶⁾ and the common occurrence of asymptomatic imaging changes.⁷⁾ This diagnostic uncertainty is especially pertinent in FLLDH, a condition that may be missed on initial imaging.⁸^,⁹⁾ Although transforaminal epidural steroid injections are an effective non-operative option for FLLDH,¹⁰^,¹¹⁾ clinicians must consider the potential for direct needle trauma to neural structures¹²⁾ and the possibility that the relief provided may not be permanent, with some patients later proceeding to surgery.¹³⁾

Furthermore, treatment decisions in elite athletes often present a clinical dilemma, with spine surgeons and sports physicians needing to balance performance pressures with long-term spinal health.¹⁴⁾ There is a clear conflict between the demand for a rapid return to competition and the need to avoid surgical intervention that could jeopardize an athlete's career longevity.¹⁵⁾ Therefore, a non-operative approach that reliably relieves symptoms while minimizing downtime is desirable.¹⁶^,¹⁷⁾

This report presents the cases of 2 elite athletes-one a swimmer and the other a figure skater-with activity-limiting low back pain secondary to a small FLLDH at L5-S1. We describe the successful application of a fluoroscopy-guided foraminal block, a technique that is conceptually distinct from a conventional nerve root block. This approach is specifically intended to infiltrate the inflammatory environment throughout the foramen, rather than targeting the exiting nerve root alone. These cases demonstrate that this approach is a safe and effective strategy for facilitating a rapid return to high-level competition.

Case Reports

Case 1: an elite swimmer

Presentation and diagnostic assessment

An elite male swimmer in his early 20s presented with left-sided low back pain that was hindering his training for a major international competition. The pain, which did not radiate to his leg, was characterized as a sensation of the "waist giving way" following intensive swimming sessions. On physical examination, there were no signs of nerve tension, and motor strength was full. Localized tenderness was present over the facet joints on the left at L4/5-S1. MRI revealed a small herniated nucleus pulposus in the left L5-S1 foramen that, consistent with the symptoms, was mildly compressing the exiting nerve root (Figure 1A and B). Although facet joint tenderness was noted, the decision was made to proceed with a foraminal block rather than a facet block. This decision was prioritized because the MRI clearly identified a structural lesion (FLLDH) corresponding to the L5 nerve root, making it the primary diagnostic target over the non-specific physical finding of facet tenderness.

Figure 1

Pre-intervention magnetic resonance and intra-operative fluoroscopic images for case 1 (an elite swimmer) with low back pain. (A) Sagittal T2-weighted magnetic resonance image showing a small, far-lateral disc herniation at L5-S1 (arrowhead). (B) Axial T2-weighted magnetic resonance image showing a small, left-sided far-lateral disc herniation at L5-S1. (C) An initial small injection of contrast medium demonstrates correct needle placement within the left foramen at L5-S1. (D) Contrast medium was observed to spread diffusely throughout the foraminal space, confirming that the foraminal block technique worked as intended.

Therapeutic intervention

With the patient prone, the left foramen at L5-S1 was targeted under fluoroscopic guidance using a 45-degree oblique view. A 22-G spinal needle was advanced via a subpedicular approach, with small incremental injections of contrast medium administered as the needle was carefully advanced into the superior aspect of the foramen. The needle tip was intentionally kept just short of the exiting nerve root to ensure that the injection was perineural rather than intraneural. This technique enabled diffuse intraforaminal spread and, importantly, produced a mild provocation response attributable to the contrast medium injection pressure rather than mechanical needle irritation, which faithfully reproduced the patient's presenting pain (Figure 1C and D). Next, a therapeutic injectate consisting of 2 mL of 1% lidocaine (Xylocaine; Sando Co., Ltd., Tokyo, Japan) mixed with 0.5 mL (1.65 mg) of dexamethasone (Decadron^® Phosphate Injection 1.65 mg; Sandoz Pharma K.K., Tokyo, Japan) was delivered.

Follow-up and outcome

The therapeutic outcome was excellent. The patient obtained immediate and complete relief from his low back pain, which was confirmed by pain-free forward and backward bending post-procedure. He was very satisfied with this result, which enabled him to travel and compete successfully in a major international competition as planned.

Case 2: an elite figure skater

Presentation and diagnostic assessment

An elite female figure skater in her late teens presented with right-sided low back pain that had started following a major international event at the end of the previous season. The pain was localized to her right iliac crest area and was exacerbated by movements that were essential to her sport, including landing jumps and hyperextension maneuvers. The pain was severely compromising her training for the upcoming national championships, a critical qualifying competition for a premier global event. On examination, she had localized tenderness over the right iliac crest and L5 spinous process but no neurological deficits in the lower extremities. Lumbar MRI confirmed a right-sided, far-lateral disc herniation at the right L5-S1 foramen (Figure 2A and B). An L5 spondylolysis was also identified.

Figure 2

Images for case 2, an elite figure skater with right-sided low back pain. (A) Sagittal T2-weighted magnetic resonance image showing a small, far-lateral disc herniation at L5-S1 and L5 spondylolysis (arrowheads). (B) Axial T2-weighted magnetic resonance image showing a small, right-sided far-lateral disc herniation at L5-S1. (C) Anteroposterior fluoroscopic view demonstrating precise needle placement in the right L5-S1 foramen. (D) Spread of contrast medium confirming broad infiltration within the foramen.

Therapeutic intervention

The patient underwent a therapeutic intervention at the right L5-S1 foramen using a similar approach. Positioned prone, the target was visualized using a standard anteroposterior fluoroscopic view. Under continuous fluoroscopic guidance, a 22-G spinal needle was advanced via a subpedicular approach toward the superior part of the foramen (Figure 2C). Advancement of the needle was guided by direct visualization of the needle tip against the bony anatomy, without the use of contrast puffs, to precisely control its final depth. The needle tip was intentionally halted just short of the exiting nerve root, using a technique we call "stopping just short," to ensure that its final position was in the paraneural space and to prevent any mechanical irritation to the nerve root itself. A final contrast injection confirmed diffuse infiltration throughout the foramen (Figure 2D) and, crucially, elicited a concordant pain response. This response was clearly a result of hydraulic distention of the inflamed foraminal tissues, not direct needle-to-nerve irritation, and it exactly matched the symptoms that had compromised her athletic performance. Next, a therapeutic injectate consisting of 2 mL of 1% lidocaine and 0.5 mL (1.65 mg) of dexamethasone was administered.

Follow-up and outcome

The foraminal block provided sufficient pain relief to allow the athlete to perform successfully in her scheduled ice shows. It ultimately enabled her to continue the intensive training regimen required for her to prepare for the crucial qualifying season.

Patient perspective

From the athletes' perspectives, this intervention was career-saving. The pain had induced significant anxiety, threatening their participation in high-stakes competitions. The immediate relief from this non-operative procedure restored their function, allowing a successful return to elite competition. Both expressed profound gratitude for preserving their athletic careers.

Discussion

Management of low back pain in elite athletes requires an intervention that is not only effective but unequivocally safe, minimizing any risk to their careers. This report describes the use of a foraminal block as such an intervention. The value of this technique lies in its safety, multifaceted efficacy, and clinical superiority over other options in this specific population.

A safety-first strategy: foraminal block vs. nerve root block

A critical aspect of our technique is the clinical strategy that differentiates it from a conventional nerve root block or transforaminal epidural steroid injection.

Although the transforaminal approach is similar, a conventional block often involves needle advancement toward the nerve root to seek a paresthesia response for diagnostic confirmation. For an elite athlete preparing for a career-defining event, this diagnostic step carries an unacceptable iatrogenic risk (e.g., direct needle trauma or post-procedural neuralgia).¹¹^,¹⁸⁾ Such a complication, even if temporary, would be a significant adverse outcome. Therefore, we judged this conventional diagnostic step to be clinically contraindicated in this high-stakes population.

In contrast, our foraminal block strategy was optimized for safety as the absolute priority.

The needle tip was intentionally positioned in the paraneural space-a technique we call "stopping just short" -to deliberately avoid nerve root contact. This 'safety-first strategy' minimizes iatrogenic risk by shifting the therapeutic target from the nerve root itself to the entire inflammatory environment and potential perineural adhesions throughout the foramen.

Multifaceted efficacy: mechanism of action and confirmation of the diagnosis

The therapeutic success of this approach is attributed to its ability to infiltrate the entire pathological environment of the foramen. The pathophysiology of foraminal neuropathy extends beyond simple mechanical compression; it involves a diffuse inflammatory state driven by cytokines such as interleukin-1β and tumor necrosis factor-α, as well as irritation from fibrous adhesions.¹⁹^,²⁰⁾ Our paraneural injection technique delivers corticosteroids throughout this complex inflammatory milieu and may simultaneously have a hydrodissection effect on perineural adhesions, likely explaining the rapid pain relief observed.

Although MRI did not show overt signs of active inflammation, such as high-intensity signal or contrast enhancement within the foramen, the pathophysiology of radiculopathy from disc herniation is understood to involve not just mechanical compression but also a significant 'chemical radiculitis' driven by inflammatory cytokines. The immediate and effective pain relief provided by the corticosteroid injection in both athletes strongly supports the hypothesis that this inflammatory environment was the primary therapeutic target.

Furthermore, the efficacy of this technique is both diagnostic and therapeutic. In athletes without classic radiculopathy, identifying a small FLLDH as the definitive pain source is a diagnostic challenge.²¹⁾ A foraminal block, by reproducing concordant pain during injection of contrast, provides unequivocal confirmation of the diagnosis and can guide subsequent treatment.

This diagnostic capability was particularly crucial in these cases. While both athletes presented with atypical symptoms-localized to the iliac crest or described as a 'waist giving way' sensation -rather than classic lower-limb radiculopathy, such presentations can occur with FLLDH due to irritation of the dorsal root ganglion or the posterior ramus of the nerve root, leading to referred pain patterns.

The definitive diagnostic confirmation in both cases was the reproduction of this specific, atypical pain (concordant pain provocation) during the injection of contrast medium.

This response, caused by hydraulic distention rather than direct needle irritation, confirmed the L5-S1 foramen affected by the FLLDH as the primary pain generator.

Clinical superiority as a non-operative strategy for elite athletes

For an elite athlete, the greatest advantage of the foraminal block is that it facilitates an immediate return to competition. Although minimally invasive surgery has shortened recovery times, it still requires a post-operative rehabilitation period that is untenable for an in-season athlete.²²^,²³⁾ Moreover, there is a risk that an athlete may not return to their pre-operative competitive level after surgery.²⁴⁾ Our approach, which combines definitive diagnosis with safe therapy, enables athletes to bypass these surgical risks and career interruptions, positioning it as a valuable first-line treatment option, particularly when a critical competition is imminent.

Future directions: role of ultrasound guidance

Ultrasound Guidance offers the distinct advantage of real-time visualization of soft tissues, including nerves and vasculature, allowing the operator to "see and avoid" these structures. In contrast, our fluoroscopy-guided approach relies on precise navigation relative to bony landmarks (e.g., the subpedicular space) to ensure the needle tip remains paraneural. While fluoroscopy provides superior visualization of the bony foramen, a future combination of both fluoroscopy and ultrasound guidance may represent an ideal evolution of this technique. This dual-modality approach could leverage the strengths of both, maximizing safety by definitively visualizing both the osseous target and the adjacent neural structures.

Limitations

The primary limitation of this report is its short follow-up period. Although the intervention proved invaluable as a bridging therapy for a critical competitive season, its ability to prevent recurrence in the long term is unknown. Future research should investigate long-term outcomes to better define the role of this technique in the overall management algorithm.

Furthermore, the success observed in these cases is likely attributable to the specific patient population: young athletes with minimal spinal degenerative changes and a single, clearly defined pathological lesion (FLLDH). The applicability and efficacy of this specific block as a standalone treatment in patients with multilevel degenerative disease or multifactorial pain (e.g., co-existing facet arthropathy) may be limited and require further investigation.

Conclusions

For elite athletes with debilitating low back pain from FLLDH, a foraminal block represents an effective non-operative intervention, whose primary advantage is a safety profile that deliberately avoids direct nerve root contact to minimize the risk of iatrogenic sequelae that could jeopardize an athlete's career. Its efficacy is multifaceted, providing not only a definitive diagnosis through provocation but also therapeutic relief by targeting the inflammatory environment throughout the foramen. This approach facilitates a rapid return to competition, positioning it as a superior strategy that can preserve an athlete's immediate and long-term career goals.

Conflicts of Interest Disclosure

All authors have no conflict of interest.

Informed Consent

Written informed consent was obtained from the patient for the publication of this case report.

References

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