Intraspinal cyst communicating with the intervertebral disc in the lumbar spine: discal cyst

Treatment of gas-containing lumbar disc cysts via a combination of posterior and extraforaminal approaches in arthroscopic-assisted uni-portal spine surgery: a case report and literature review

BACKGROUND

Gas-containing lumbar disc cysts (LDCs) are a rare spinal pathology that frequently manifest as sciatica and exhibit clinical features akin to those observed in lumbar disc herniation. Their radiological presentation closely resembles that of synovial cysts, which can result in misdiagnosis, and their development is hypothesized to be associated with the 'vacuum phenomenon' observed in degenerative discs. Previous literature has documented various treatment modalities for disc cysts. In this report, we successfully excised the lesion using a combination of a posterior approach and an extraforaminal approach, facilitated by arthroscopy-assisted uniportal spinal surgery.

CASE PRESENTATION

An 85-year-old male patient developed persistent low back pain one month prior, accompanied by radiating discomfort in both lower extremities, predominantly on the right. Lumbar magnetic resonance imaging (MRI) and computed tomography (CT) scans revealed hypertrophy of the ligamentum flavum at the posterior margin of the L4/5 level, accompanied by spinal canal stenosis, and a gas-containing cyst on the right side extending into the extraforaminal region, which resulted in neural compression and functional impairment. The patient was treated using the AUSS technique. During the procedure, a unilateral posterior approach was initially employed to achieve unilateral laminotomy for bilateral decompression (ULBD) and excision of the intracanal cyst, followed by resection of the cysts in the foraminal and extraforaminal regions via an extraforaminal approach.

CONCLUSION

Although gas-containing lumbar disc cysts are rare, the combined dual-approach AUSS technique has yielded favorable clinical outcomes. Postoperatively, the patient experienced marked improvement in lower limb pain and numbness; CT imaging confirmed complete cyst resection and adequate decompression of the dural sac and nerve roots.

Cysts and hematomas in the spine: Rare Entities

INTRODUCTION

Intervertebral discs are part of the vertebral column and are considered the pads that help in cushioning and flexibility. These discs consist of nucleus pulposus, annulus fibrosus, and cartilage end plate and their major functions include spinal motion and loading. However, they are prone to numerous pathologies such as intradiscal hematoma and discal cyst formation that may significantly alter the biomechanics of the spine and hence the quality of life of the patient. This case report aims to shed light on these rare pathologies.

CASE PRESENTATION

The following is a report on two cases demonstrating the difficulties in managing patients with intradiscal hematoma and discal cysts. Both cases are non-traumatic. The first case includes a 23-year-old male patient with right-sided lumbosacral pain unresponsive to conservative measures diagnosed with intradiscal hematoma using MRI. The second case concerns a 21-year-old male with left lumbar cruralgia following a motor vehicle accident. Conservative management at the onset helped to give a short time relief and when it relapsed it led to the diagnosis of an extradural compressive cyst that called for surgery.

DISCUSSION

An intradiscal hematoma provokes severe pain increasing with intraspinal pressure. Discal cysts, which are more frequent in young people, most likely manifest clinical signs of disc herniations. The pathophysiological theories may include the presence of hematomas or a gradual degenerative process due to mechanical stress. An MRI scan is essential for correct diagnosis and developing a proper treatment strategy for both diseases. The management of the condition includes medical treatment, physical therapy, injections, and surgical procedures for chronic cases.

CONCLUSION

The diagnosis and management of intervertebral disc pathology is quite challenging. The first case presents the deficiency of minimizing conservative approach in the management of intradiscal hematomas while the second case demonstrates the propensity for symptom reappearance in discal cysts and therefore the effectiveness of surgical management. MRI and other forms of imaging are vital in the diagnosis of the disease and in planning treatment. Science has embarked on the exploration of the exact causes of these diseases to enhance the lives of patients and the efficiency of the management of such illnesses.

Imaging review of the atypical spinal epidural space pathologies

Pathologies affecting the spinal epidural space (SES) comprise various abnormalities. However, they all have the potential to cause thecal sac narrowing or spinal cord compression. In this review, we group these pathologies into degenerative, infective, neoplastic, vascular, traumatic, and others, focusing on their imaging features. Degenerative pathologies of the SES range from disc to facet disease, with a particular emphasis on the less common degenerative pathologies in this review. Infective pathologies affecting the epidural space include spondylodiscitis and associated epidural phlegmon and abscess. Neoplasms arising from typical SES components include neurofibroma, hemangioma, and liposarcoma. MRI is the best modality to assess the anatomy and abnormalities of the epidural space. MRI, combined with computed tomography, or a radiograph, is useful for the evaluation of bones or radiopaque foreign bodies.

Evaluation and Treatment of Lumbar Spine Extradural Cysts: A Narrative Review

The main objective was to describe the different types and characteristics of lumbar spine extradural cysts and their optimal treatment options with a focus on endoscopic technique. We searched Pubmed, EMBASE, Medline, and Google Scholar for articles published between 1967 and 2020 using the keywords "Spinal Cyst," "Extradural Cyst," and "Lumbar Cyst." The various anatomical and histological types of the extradural cysts with their presentations, etiologies, imaging, and optimal treatment with a focus on endoscopic techniques were reviewed from the articles. Lumbar spinal cysts are relatively rare pathologies that might cause radicular symptoms similar to lumbar disc herniation. Spinal extradural cysts are classified either histologically based on the cyst lining tissues (synovial cysts or non-synovial, ganglion cysts) or anatomically based on the structure of origin (epidural cysts, ligamentum flavum cysts, discal cysts, post-discectomy pseudocysts, posterior longitudinal ligament cysts, facet cysts). Surgical excision is the recommended treatment of symptomatic cysts with endoscopic techniques being a viable option. Extradural lumbar cysts can be identified based on their histological structure or depending on their structure of origin. Regardless of their classification, they could all give similar clinical findings, and the optimal treatment would be surgical excision with endoscopic technique being a viable option with a satisfactory outcome.

Postoperative discal pseudocyst: Report of A case with an unusual complication after microlumbar discectomy and successful treatment by transforaminal endoscopic lumbar decompression

Background

Lumbar discal pseudocysts are uncommon complications that can arise following lumbar spine surgery. It manifests as a fluid-filled sac near the intervertebral disc, causing pain and discomfort. Understanding its causes, symptoms, and management is crucial for patients and healthcare professionals involved in postoperative spinal care.

Case Description A

35-year-old female developed a discal pseudocyst after undergoing laminectomy and discectomy for lumbar disc herniation. The patient presented with recurrent lower back pain, radiculopathy, and neurological deficit two months post-surgery. Imaging revealed a discal pseudo cyst causing compression of the traversing right L5 nerve root. Given the refractory nature of her symptoms, an endoscopic procedure was offered. Using the transforaminal endoscopic technique, the pseudo cyst was identified and removed, leading to immediate symptomatic relief.

Conclusion

This article reports the rare occurrence of discal pseudocyst and highlights the use of endoscopic techniques in its surgical management. Surgeons should be aware of the minimally invasive techniques, as they can offer less morbidity, shorter recovery times, and reduced healthcare costs compared to traditional open surgery.

A rare discal cyst with concurrent double-level isthmic lumbar spondylolisthesis: a case report and literature review

We presented a 47-year old male diagnosed as a discal cyst with concurrent isthmic lumbar spondylolisthesis, which was not reported in the literature previously. A cystectomy with two-segmental transforaminal lumbar interbody fusion and instruments was performed. The association between concurrent discal cyst and isthmic spondylolisthesis may be illuminated by excessive strain and focal degeneration of the disc. Preoperative discography is probably unnecessary when surgical resection and histopathology are indicated for the patient.

Discal cysts and pseudocysts: Single center experience

Introduction

Current knowledge of intervertebral discal cysts is restricted to case reports and surgical case series, typically in young adult males presenting with back pain and radiculopathy.

Objective

We review our single-center experience to describe presentation, management, and outcomes of these rare lesions.

Methods

We performed a retrospective electronic search of our institution database using key words "discal cyst," "disc cyst" and variations. Clinical presentation, imaging findings, management and outcomes were reviewed and tabulated.

Results

Nine patients were identified (4 female), with mean age 49.1 years. Three patients had prior surgery at the level of the cyst. Seven patients presented with back pain, five with additional radiculopathy, one patient with radiculopathy alone, and one asymptomatic. Most discal cysts occurred at L5-S1, were left-sided, paracentral in location with a T2 hypointense rim and variable enhancement. One patient underwent primary cyst resection. Amongst 6 patients who underwent primary image-guided procedures, two had sustained pain relief, three proceeded to cystectomy, microdiscectomy and/or posterior decompressive surgery, and two were lost to follow-up.

Conclusion

Our retrospective cohort includes a wider age group with more heterogeneous clinical features, treatment approaches and response to therapy than that described in the literature. CT or fluoroscopy-guided steroid injection provided short-term symptomatic relief with several cases managed definitively with surgery. Further research is required to better understand and manage these rare lesions.

Clinical impact

Discal cysts and pseudocysts occur in a wider range of patients and with more heterogenous presentations than previously described. Imaging-guided intervention can provide short-term symptomatic relief, but further research is required to optimize long-term management.

A multilocular discal cyst extending from the spinal canal to the extraforaminal region: A case report

BACKGROUND

Lumbar discal cysts are intraspinal extradural cysts communicating with the intervertebral disc. The usual location and morphology are in the caudal ventrolateral epidural space of the spinal canal, without extension to the neural foramen or crossing the midline and described as a well-defined homogeneous oval or spherical cyst on low and high signal intensities observed in lumbar lesions on T1- and T2-weighted magnetic resonance imaging, respectively. We report an unusual lumbar discal cyst in terms of the lesion location and morphology.

CASE PRESENTATION

A 33-year-old-man presented with lower back and right anterior thigh pain. Magnetic resonance imaging revealed multilocular cystic lesions in the cranial ventrolateral epidural space at L2-L3 with low and high signal intensities on T1- and T2-weighted magnetic resonance imaging, respectively. We performed a full-endoscopic transforaminal cystectomy under general anesthesia.

CONCLUSION

Lumbar discal cysts should be considered a differential diagnosis for multilocular intraspinal cystic lesion.

Postoperative discal pseudocyst caused by percutaneous endoscopic lumbar discectomy: two case reports and a literature review

Postoperative discal pseudocyst (PDP) is a rare complication that can occur after percutaneous endoscopic lumbar discectomy (PELD), microendoscopic discectomy, and laminectomy. The PDP pathogenesis and pathological process remain unclear. We described two PDP cases following PELD, with long-term follow-up results. The first patient was an Asian male, 30 years old, who experienced unbearable low back pain with right lower limb radiating pain for 2 years. The second patient was also an Asian male, 21 years old, who experienced low back pain with bilateral lower limb numbness. Both patients were diagnosed with lumbar disc herniation, underwent PELD, and relapsed after discharge. The diagnosis was PDP in each case, and conservative treatment was initiated with oral anti-inflammatory drugs and rest. Eventually, the symptoms in both patients resolved. Magnetic resonance imaging showed that the discal cysts had disappeared. The follow-up of these two PDP cases after PELD showed good results, demonstrating that PDP may be a self-healing disease. Conservative treatment is effective, and surgery should be performed only in an emergency. These case reports and literature review can help improve the understanding of PDP.

Discal Cyst, a Physical Risk: A Case Report on Endoscopic Resection

Discal cysts are a rare diagnosis involving the formation of an intraspinal extradural cyst. They are a diagnostic challenge as it is difficult to differentiate discal cysts from other causes of back pain, neurological deficit, and radiculopathy. Due to its rarity, there is a lack of research-based evidence on the optimal management of the discal cyst. This case report aims to increase awareness of this diagnosis and to highlight a possible treatment option for this condition.

Surgical treatment of recurrent postoperative discal pseudocyst: A case report and literature review

INTRODUCTION

Postoperative discal pseudocyst (PDP) is rare. Few studies have reported on the recurrence of PDPs, and there is a lack of understanding of their clinical features and treatment methods. This study discusses the clinical characteristics and treatment of recurrent PDPs.

PATIENT CONCERNS

A 25-year-old man presented with radiating pain and numbness in the lateral left calf and dorsum of the foot.

DIAGNOSIS

Postoperative discal pseudocyst.

INTERVENTIONS

He underwent lumbar discectomy, which provided immediate postoperative relief. However, the symptoms recurred 45 days later. Magnetic resonance imaging (MRI) showed a lesion compressing the dura and nerve roots at the site of the previous surgery. The lesion appeared hypointense on T1-weighted imaging and hyperintense on T2-weighted imaging. The patient was treated conservatively for 1 month without significant relief. He then underwent lumbar discectomy and cyst removal, which immediately relieved his symptoms. However, 27 days later, the patient again developed the same symptoms. MRI examination showed recurrence of PDP. As 1 month of conservative treatment failed to relieve the patient's symptoms, we performed posterior instrumented lumbar fusion and cyst removal.

OUTCOMES

The patient's symptoms disappeared, and have not recurred for 1 year at the time of writing.

CONCLUSIONS

PDP is a rare complication of lumbar discectomy. Repeat lumbar discectomy can effectively treat PDP, but the cyst can recur. We, for the first time, used posterior instrumented lumbar fusion to successfully treat recurrent PDP.

Discal cyst: a rare cause of low back pain and sciatica

We report a case of a 54-year-old man suffering from sciatalgia unresponsive to medical treatment. Imaging revealed a discal cyst the level L3-L4, a rare cause of low back pain, which has characteristic imaging features. In particular, on Magnetic Resonance Imaging it appears as a cystic formation with fluid content, which usually arises from the posterior contour of the intervertebral disc and it frequently has air bubbles within it. The patient underwent surgical treatment with resolution of symptoms.

Revision surgery for symptomatic postoperative pseudocyst following full-endoscopic lumbar discectomy: clinical characteristics and surgical strategies

BACKGROUND

A symptomatic postoperative pseudocyst (PP) is a cystic lesion that is formed in the operation area of the intervertebral disc, leading to worse symptoms. Some minority patients who developed PP experienced rapidly aggravating symptoms and could not be treated by any kind of conservative treatment. However, no clinical studies have evaluated the clinical characteristics and surgical strategies of symptomatic PP requiring a revision surgery after full-endoscopic lumbar discectomy (FELD). This study aimed to demonstrate the clinical characteristics and surgical strategies of symptomatic PP requiring a revision surgery after FELD.

METHODS

We retrospectively analyzed the data of patients who received FELD revision surgeries due to symptomatic PP formation between January 2016 and December 2021. Common characteristics, time intervals of symptom recurrence and revision surgery, strategies for conservative treatment and revision surgery, operative time, imaging characteristics, numeric rating scale (NRS) score, Oswestry disability index (ODI) and overall outcome rating based on modified MacNab criteria were analyzed.

RESULTS

Fourteen patients (males = 10, females = 4), with a mean age of 24.4 years, were enrolled. The mean time intervals of symptom recurrence and revision surgery were 43.5 and 18.9 days respectively. While the patients were conservatively managed with analgesics and physical therapy, pain persisted or progressively worsened. In comparison to the initial herniated disc, the PP was larger in 11 cases, and up- or down-migrated in four cases. The PP location included the lateral recess (n = 12), foraminal (n = 1), and centrolateral (n = 1) zones. One of the two cases treated by percutaneous aspiration (PA) was eventually treated by FELD as pain was not relieved. Follow-ups revealed an improved mean NRS score from 7.1 to 1.4, mean ODI from 68.6 to 7.9% and promising overall surgical outcomes.

CONCLUSIONS

The progressively severe pain experienced due to PP might be a result of its enlargement or migration to the lateral recess and foraminal zones. As complete removal of capsule is the goal, we recommend FELD instead of PA.

Lumbar discal cyst and post-operative discal pseudocyst: a case series

Four cases of lumbar cyst (2 discal cysts and 2 post-operative discal pseudocysts) who presented predominantly with features of sciatica without any motor, sensory or sphincteric disturbances. The patients were treated conservatively, and the management was aimed to avert any untoward surgical intervention taking into consideration patient safety and care. Two had previous lumbar decompressive discectomy. During the mean follow-up period of 13 months, there was progressive recovery of symptoms in all our 4 patients. All our patients were successfully managed by conservative approach. An intervertebral disc cyst should be considered in young patients in the differential diagnosis of any extradural intraspinal mass ventral to the thecal sac, notwithstanding its rarity. Alongside, conservative management can be offered as first line of management with appropriate patient selection that is absence of any motor/sensory/sphincteric disturbances. Facetal micro-instability could be one of the aetiologies of this pathology which necessitates further study.

Successful Full Endoscopic Surgery for L5 Radiculopathy Due to L4-5 Discal Cyst and Disc Herniation in a Professional Baseball Player

Discal cysts are rare intraspinal extradural cysts that communicate with the corresponding intervertebral discs, and the diagnosis is difficult to distinguish from other causes of low back pain and radiculopathy. Optimal management for this type of cyst has not been determined because of its rarity. Here, we report successful treatment of a discal cyst and lumbar disc herniation using full endoscopic surgery in a professional baseball player with a chief complaint of weakness in his left lower leg. He had been treated conservatively but symptoms did not improve. Discography helped us to differentially diagnose discal cyst from other cystic lesions. Conventional surgical treatment would have resulted in considerable loss of baseball playing time for the patient. We opted to perform minimally invasive transforaminal full endoscopic surgery under local anesthesia to treat the discal cyst and lumbar disc herniation simultaneously without resection of bone and ligament handling. We removed the discal cyst and disc herniation, which released tension on the left nerve root at the L5 level, and then performed thermal annuloplasty to avoid recurrence. Postoperative course was good and he returned to play baseball at his original competitive level 3 months later. To our knowledge, there have been no previous reports of successful full endoscopic surgery for discal cyst and lumbar disc herniation performed simultaneously in a professional baseball player. It can be difficult to decide on the proper treatment for discal cysts, but full endoscopic surgery for symptomatic discal cyst might be one good option especially for elite athletes.

Could gas-filled pseudocyst mimick extruded disc herniation?

There are case reports and small case series in the literature reporting gas-filled pseudocysts (GFP). However, a systematic review presenting overall view of the disease and its management is still lacking. In the present study, we aimed to make a systematic review of GFP cases, and present an exemplary case of ours. Our second aim was to discuss current theories for pathogenesis of GFP. A systematic review of GFP was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Two large-scaled data search engines were used. A total of 53 articles were retrieved from the literature and presented with an exemplary case of ours. Mean age of the historical cohort was 59.47 years. There were 66 male (54.1%) and 56 female (45.9%) patients. The most prevalent clinical presentation was radicular sign/symptom in lower limbs with (29.1%) or without low back pain (LBP) (67%). Gas-filled pseudocyst has most commonly been diagnosed at the lower lumbar spine (L4-L5, 45.3%; L5-S1, 37.7%). Surgery was the treatment of choice in most of the patients (80%). In the whole cohort, 79.1% of the patients had complete recovery. Gas-filled pseudocysts are rarely observed in daily practice. They present mostly in men at the age of 60s. Precise differential diagnosis determination using appropriate imaging would help clinicians treat the patients properly. Gas-filled pseudocysts should be treated similarly to other spinal pathologies causing nerve root compression.

Subacute hemorrhagic cyst of the ligamentum flavum occurred in the lumbosacral transitional vertebra presenting as progressive lumbar nerve root compression: a case report

The lumbosacral transitional vertebrae (LSVT) has been reported to be a cause of lumbar disc herniation as a result of mechanical stress, however there were no reports about relationship between LSTV and hemorrhagic intervertebral cystic lesion. We report a rare case of a hemorrhagic intravertebral cystic lesion that occurred in the LSVT of a 42-year-old man and had a subacute course of lumbar nerve root compression. He presented our hospital with complain of increasing left leg pain for one week. Contrast-enhanced MRI (Gd-T1WI) showed a heterogenous contrast-enhanced effect on the nodule at the entrance of the left pedicle root of L6. The LSTV was classified as Type IIIA using the Castellvi's classification, and the nodule was found on the ipsilateral of the lumbarization. From the imaging findings, disc cysts, ganglion cysts, synovial cysts, disc sequestration and Schwannomas were differentials of the intravertebral canal cystic lesions; however, it was suspected to be a hemorrhagic cystic lesion because of their acute progression of his symptoms, his relatively young age and imaging findings. His symptoms improved shortly after the resection of the cyst and he was diagnosed as intracystic hemorrhage of a ganglion in the ligamentum flavum. There were no features suggestive of recurrence of the cystic lesion in the follow-up MRI on 6 months after the surgery. It was speculated that in the LSTV, twisting movements act on the upper part adjacent to the transitional vertebra, causing microtrauma around the facet joint that leads to the forming a hemorrhagic cyst following damage around the joint capsule. It is difficult to make a diagnosis of hemorrhagic cyst from imaging alone. It must be suspected from the aspect of age (relatively young), gender (male), clinical course (acute to subacute) and MR imaging (various signal intensity patterns on T2WI and contrast effect on Gd enhancement).

Transforaminal percutaneous endoscopic discectomy for symptomatic gas-filled discal cysts-report of three cases and literature review

OBJECTIVE

The aim of this retrospective study is to review our experience in the diagnosis and role of transforaminal percutaneous endoscopic discectomy (TPED) for symptomatic gas-filled discal cysts.

METHODS

Between May 2014 and June 2017, 3 patients from Lishui Center Hospital (Lishui China), who underwent TPED for symptomatic gas-filled discal cysts, were analyzed. The clinical features, imaging findings, operative findings, and treatment outcomes are presented. In addition, relevant literature regarding gas-filled discal cysts was searched using PubMed, and their characteristics, clinical features, therapeutic strategies, and survival outcomes were reviewed.

RESULTS

The median age of the patients was 56.7 years (range, 55-60 years). In all patients, a discal cyst was located in the lumbar region, and the patients presented with backache and numbness in the lower extremities. The diagnosis was made by lumbar 3-dimensional computed tomography (3D-CT) or magnetic resonance imaging (MRI). All patients underwent TPED. All patients recovered successfully and were eventually discharged. Eighteen articles were identified from the searches of the database, and a total of 42 patients were included. There were 28 males and 14 females. The mean age was 56.8 years, ranging from 27 to 85 years. Lower back pain was the major symptom. Twenty-two patients underwent surgery, 4 patients underwent percutaneous needle aspiration, 2 patients underwent drug therapy, 13 patients received nonoperative treatment, and 1 patient was unknown.

CONCLUSION

TPED for gas-filled discal cysts is feasible, effective, and successful, although it should be performed by an experienced surgeon with awareness of the potential risk of severe nerve root injury.

Symptomatic postoperative discal pseudocyst following percutaneous endoscopic lumbar discectomy: A case report and review of the literature

RATIONALE

Percutaneous endoscopic lumbar discectomy (PELD) is an effective treatment for lumbar disc herniation and postoperative discal pseudocyst (PDP) can rarely develop after PELD.

PATIENT CONCERNS

A 30-year-old man experienced low back pain and pain in the right lower extremity for 1 month, which aggravated for 3 days.

DIAGNOSES

Preoperative CT and MRI showed lumbar disc herniation at the L4/5 level. Then the patient underwent PELD under local anesthesia and his symptoms disappeared immediately after surgery. After 37 days of PELD, the patient complained of recurrent low back pain on the right side, and pain on the outer side of his lower leg. MR imaging revealed cystic mass with low signal on T1-weighted images (T1WI), and high signal on T2-weighted images (T2WI). The patient was diagnosed with a symptomatic PDP after PELD.

INTERVENTIONS

Initially, the patient was treated with conservative treatment, including administration of aescin and mannitol by intravenous infusion, physical therapy, sacral canal injection. Then he underwent discography at L4/5 and ozone ablation under local anesthesia.

OUTCOMES

The patient's condition improved significantly after 1 week of surgery and was discharged. One-year and 3-month follow-up revealed no recurrence of low back pain and leg pain.

LESSONS

PDP is one of the rare complications of PELD, usually occurs in young patients. Patients with PDP have a low signal intensity on T1WI and high signal intensity on T2WI, which can be treated by conservative treatment, interventional therapy, and surgical treatment.

Symptomatic Postoperative Discal Pseudocyst After Percutaneous Endoscopic Interlaminar Discectomy: Case Report and Literature Review

Background

A postoperative discal pseudocyst (PDP) is a cystic lesion that is formed in the operation area of the intervertebral disc, leading to recurrence or even worse symptoms. To our knowledge, to date, there is no research focusing specifically on PDP following percutaneous endoscopic interlaminar discectomy (PEID).

Case presentation

We present the case of a 27‐year‐old man with L₅S₁ intervertebral disc herniation who was treated with PEID after failed conservative treatment. His leg pain was relieved immediately but reoccurred on the 40th day. MRI showed a PDP. Because loxoprofen and bedrest were ineffective and the patient was anxious, we performed a cystectomy. The patient's symptoms were significantly relieved, and a 6‐month follow up showed no recurrence both clinically and on MRI.

Conclusion

A PDP is more likely to form using the interlaminar approach than the transforaminal approach. For patients with mental stress, severe pain, and neurological symptoms, surgery is suggested to remove the cyst. Discectomy cannot be performed when disc degeneration is mild.

Clinical, magnetic resonance imaging and histologic findings of canine thoracolumbar discal pseudocyst: 8 cases (2014-2019)

OBJECTIVE

To report the clinical and MRI features, and histologic findings of thoracolumbar discal pseudocyst in dogs.

MATERIALS AND METHODS

The records of eight dogs with thoracolumbar discal cyst-like structures were retrospectively collected to record their clinical signs, MRI features and surgical and histologic findings.

RESULTS

Eight dogs with surgically and histologically confirmed thoracolumbar discal pseudocysts were included in the case series. Six dogs presented with acute onset and two dogs presented with subacute onset of thoracolumbar myelopathy. MRI showed compressive thoracolumbar myelopathy due to a round to oval-shaped epidural mass lesion communicating with the intervertebral disc, iso/hypointense on T1WI and mostly hyperintense on T2WI, associated with a variable contrast-enhancing wall, compatible with a cyst-like structure. These structures were surgically visualised and removed through a mini-hemilaminectomy or hemilaminectomy and submitted for histologic investigation. One dog also underwent cytologic examination of the cystic content. Similar to that in humans, histology revealed a cyst-like nature with a wall consisting of dense fibrous connective tissue containing clusters of chondroid cells accompanied by groups of notochordal cells and occasional erythrocytes; however, a real epithelial lining was missing and the term pseudocyst seemed more appropriate.

CLINICAL SIGNIFICANCE

This report describes clinical signs, and MRI and histologic findings of discal pseudocysts in dogs with thoracolumbar myelopathy. Despite being rare, discal pseudocysts should be considered as a differential diagnosis in dogs with acute onset thoracolumbar myelopathy.

Classification of Intervertebral Disc Disease

Intervertebral disc disease (IVDD) has been recognized in dogs since the 1800s, when the first descriptions of extruded disc material within the vertebral canal were published. In the intervening time our understanding of intervertebral disc pathology in dogs and cats has increased dramatically, with many variations of IVDD described. Whilst the volume of literature and collective understanding of IVDD has expanded, there has also been scope for confusion as the definition of intervertebral disc disease, with its myriad different manifestations, becomes more complicated. A large volume of literature has aimed to combine the use of histopathology, diagnostic imaging and clinical findings to better understand the various ways in which IVDD can be classified. Much of this research has focused on the classification of mechanisms of intervertebral disc degeneration, centering around the differences between, and overlaps in, IVDD in chondrodystrophic and non-chondrodystrophic dog breeds. However, with the increasing availability of advanced imaging modalities allowing more accurate antemortem diagnosis, the concept of IVDD has expanded to include other clinical presentations that may not fit into traditional models of classification of IVDD. This review aims to provide an up to date overview of both historical and current systems of IVDD classification, highlighting the important findings and controversies underpinning them.

Factors Influencing Patient Satisfaction After Decompression Surgery Without Fusion for Lumbar Spinal Stenosis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Decompression without fusion is a standard surgical treatment for lumbar spinal stenosis (LSS) with reasonable surgical outcomes. Nevertheless, some studies have reported low patient satisfaction (PS) following decompression surgery. The cause of the discrepancy between reasonable clinical outcomes and PS is unknown; moreover, the factors associated with PS are expected to be complex, and little is known about them. This study aimed to identify satisfaction rate and to clarify the factors related to PS following decompression surgery in LSS patients.

METHODS

We retrospectively reviewed 126 patients who underwent lumbar decompression with a minimum follow-up of 1 year. Patients were divided into 2 groups based on the PS question. The Japanese Orthopaedic Association (JOA) scores, and the Numeric Rating Scale (NRS) scores of low back pain (LBP), leg pain, and leg numbness were compared between the 2 groups preoperatively and at the latest visit. To identify the prognostic factors for dissatisfaction, multiple logistic regression analysis was performed.

RESULTS

Overall satisfaction rate was 75%. The JOA recovery rate, NRS improvement, and Short Form-8 (SF-8) were significantly higher in the satisfied group. Postoperative NRS scores of LBP, leg pain, and leg numbness were significantly lower in the satisfied group. Multivariate logistic regression analysis showed that smoking and scoliosis were significant risk factors for dissatisfaction.

CONCLUSIONS

Overall satisfaction rate was 75% in patients with LSS undergoing decompression surgery. This study found that smoking status and scoliosis were associated with patient dissatisfaction following decompression in LSS patients.

Percutaneous Endoscopic Surgery for Lumbar Discal Cyst: Two Case Reports

Discal cyst is a rare disease, the pathogenesis is not yet clear and its symptoms are very similar to lumbar disc herniation. Although some cases may regress spontaneously, most cases of lumbar discal cysts are treated surgically. At present, there is no consensus on the treatment of this disease. The authors report the clinical usefulness of the percutaneous endoscopic transforaminal surgery technique in two patients with the lumbar 4-5 discal cyst. The clinical symptoms of both patients were unilateral lower extremity pain and lower back pain. Magnetic resonance imaging of the lumbar spine revealed lumbar discal cysts, causing compression to the spinal dura and roots. Both patients received conservative treatment for more than 6 months, but the clinical symptoms persisted so surgical treatment by percutaneous endoscopic transforaminal surgery without additional discectomy was performed under local anesthesia. The symptoms were relieved immediately after removal of the discal cysts. Postoperative magnetic resonance imaging showed that both patients had complete excision of discal cysts and complete decompression of the treated segmental. There were no recurrent lesions and complications during the follow-up period. We believe that percutaneous transforaminal endoscopic surgery could be a safe, mini-invasive and appropriate method for the treatment of discal cysts.

Clinical Application of Percutaneous Transforaminal Endoscopic Surgery in Lumbar Discal Cyst

BACKGROUND

Discal cyst is very rare and can cause intractable low back pain and radiating leg pain. Symptoms are hard to distinguish from lumbar disc herniation. The best treatment for discal cyst is controversial. Most lumbar discal cysts are treated surgically, while most studies of percutaneous transforaminal endoscopic surgery are case reports. This study investigated the clinical value of percutaneous transforaminal endoscopic surgery for lumbar discal cyst.

METHODS

A retrospective study was conducted in 9 patients with a discal cyst from June 2016 to November 2018. All patients had been treated by percutaneous transforaminal endoscopic surgery via a superior vertebral pedicle notch approach. Surgical outcomes were evaluated preoperatively and postoperatively using a visual analog scale for leg pain and the Oswestry Disability Index. At the final follow-up, patients were evaluated for clinical efficacy using modified Macnab criteria.

RESULTS

All 9 patients had remission of symptoms after removal of discal cysts. Postoperative magnetic resonance imaging showed that all patients had complete excision of discal cysts and complete decompression of the treated segment. There were no recurrent lesions during follow-up. Mean operative time was 68.67 ± 14.02 minutes. Mean hospitalization time was 4.22 ± 1.64 days. Preoperative visual analog scale and Oswestry Disability Index score improved significantly after surgery. Visual analog scale leg score improved from 7.88 ± 1.05 preoperatively to 1.78 ± 0.66 at final follow-up (P < 0.05), and ODI score improved from 53.65 ± 12.46 to 16.25 ± 8.76 (P < 0.05). According to the modified Macnab criteria, 5 patients (55.6%) were rated excellent, 3 patients (33.3%) were rated good, and 1 patient (11.1%) was rated fair at final follow-up, with an overall excellent and good rate of 88.9%. There were no serious complications during follow-up.

CONCLUSIONS

Percutaneous transforaminal endoscopic surgery could be a safe, minimally invasive surgical treatment for discal cyst, particularly suitable for patients who cannot undergo general anesthesia.

Gender Differences in Pre- and Postoperative Health-Related Quality of Life Measures in Patients Who Have Had Decompression Surgery for Lumbar Spinal Stenosis

Study Design

Retrospective chart audit.

Purpose

This study aimed to investigate the gender difference in pre- and postoperative health-related quality of life (HRQOL) in patients who have had decompression surgery for lumbar spinal stenosis (LSS).

Overview of Literature

Gender differences may contribute to variations in disease presentations and health outcomes. The influence of gender on pre- and postoperative HRQOL in spinal disorders remains unclear.

Methods

We reviewed 125 patients (79 men and 46 women) who had lumbar spinous process splitting laminectomy (LSPSL) for LSS. We assessed the following clinical information: Japanese Orthopedic Association (JOA) score; numerical rating scale (NRS) for low back pain (LBP), leg pain, and leg numbness; Zurich Claudication Questionnaire; JOA Back Pain Evaluation Questionnaire; Roland- Morris Disability Questionnaire (RMDQ); and Short Form 8 (SF-8) as HRQOL. We compared the HRQOLs of men and women pre- and postoperatively.

Results

Although the preoperative NRS results for LBP were significantly higher in women (p <0.05), there were no significant differences in clinical outcomes between men and women postoperatively. For HRQOL, the RMDQ scores were significantly worse in women preoperatively (p <0.05), but no significant differences were found postoperatively between men and women. Similarly, the SF-8 mental health score was also significantly lower in women preoperatively (p <0.05), but no significant differences were noted between the two groups postoperatively.

Conclusions

LSPSL greatly reduced LBP, leg pain, and leg numbness in both genders. There were limited differences in pain and several HRQOL questionnaire responses between men and women after surgery. We found that women had greater sensitivity to and/or lower tolerance for pain than men, which led to lower HRQOL mental health scores preoperatively.

Epiduroscopic decompression of a symptomatic perineural cyst: A case report

RATIONALE

Perineural cysts in the spinal canal are usually asymptomatic. However, symptoms can occur when the cyst becomes large enough to compress a nerve root. There are still no established treatment options for this disease. In this report, we describe a case of successful decompression of the large symptomatic perineural cyst using epiduroscope.

PATIENT CONCERNS

A 42-year-old male patient visited our pain center complaining of discomfort and pain in his right posterior thigh. Magnetic resonance imaging of the patient showed a large perineural cyst (53 × 31 × 21 mm) compressing the right S1 nerve. No other abnormalities that would explain the patient's symptoms were identified.

DIAGNOSIS

Perineural cyst at the right S1 nerve.

INTERVENTIONS

We performed an epiduroscopic decompression of the perineural cyst. After advancing the epiduroscope and locating the cyst, we used the laser to make a hole in the cyst wall. Then, the epiduroscope was advanced into the cyst, and the cystic fluid was aspirated.

OUTCOMES

The symptoms of the patient were relieved after the procedure, without any complications. There was no recurrence of symptoms until 6 months after the procedure.

LESSONS

The epiduroscope is a minimally invasive method which can be used safely for decompression of symptomatic perineural cysts in the spinal canal.

Clinical outcomes of lumbar diseases specific test in patients who undergo endoscopy-assisted tubular surgery with lumbar herniated nucleus pulposus: an analysis using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ)

Purpose

This study was to evaluate clinical outcomes using a patient-oriented test that scores health-related quality of life (HRQOL) for patients after minimally invasive surgery using microendoscopic discectomy (MED) for lumbar disc hernia. Few studies regarding MED in terms of disease-specific quality of life measures using Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) have been published.

Methods

Retrospective analysis of the surgical and clinical outcomes with regard to reducing pain and improving the functional status for 31 patients who underwent MED for lumbar disc hernia was conducted. These patients were evaluated at 3-year follow-up. The evaluations were based on a visual analogue scale (VAS), the Japanese Orthopaedic Association (JOA) scoring system, and the JOABPEQ, which is an objective, patient-oriented test that assesses HRQOL in patients with lumbar disorders.

Results

A low rate of improvement was seen only in mental health until 1 year, the low rate of improvement in mental health and was independently correlated with body mass index (BMI), pre-operative scores on the Brief Scale for Psychiatric problems in Orthopaedic Patients (BS-POP), and scores on the BS-POP at 12 months post-operatively.

Conclusions

All categories of VAS, JOA scores, and all domains of JOABPEQ were significantly higher over 3 years than those obtained pre-operatively. But only mental health domain showed mild improvement until 1 year. Moreover, BMI showed a negative correlation with improvements in the mental health domain post-operatively. As patients may be mentally exhausted from lumbar disc herniation, pre-operative mental health may be improved by surgical treatment.

Tubular surgery with the assistance of endoscopic surgery via a paramedian or midline approach for lumbar spinal canal stenosis at the L4/5 level

BACKGROUND

Lumbar spinal canal stenosis surgery has recently improved with the use of minimally invasive techniques. Less invasive procedures have emerged, and microendoscopic decompression through smaller incisions is frequently performed. Tubular surgery with the assistance of endoscopic surgery procedures has led to particularly remarkable changes in surgery, with reduced tissue trauma and morbidity.

PURPOSE

The purpose of this study was to compare the clinical outcomes of two different minimally invasive decompressive surgical techniques (microendoscopic bilateral decompression surgery using the unilateral approach [microendoscopic laminectomy (MEL)] and microendoscopy-assisted muscle-preserving interlaminar decompression (MILD; ME-MILD)) using spinal endoscopy for lumbar spinal canal stenosis measured using a visual analog scale (VAS), the Japanese Orthopedic Association (JOA) score, and the JOA Back Pain Evaluation Questionnaire (JOABPEQ), which is based on a patient-oriented scoring system.

STUDY DESIGN

This study was a retrospective review of prospectively collected surgical data.

METHODS

The study included 81 patients (MEL 39 patients, 20 men and 19 women, mean age 68.9 years; and ME-MILD 42 patients, 22 men and 20 women, mean age 73.1 years) with lumbar spinal stenosis (LSS). The indications for surgery were moderate-to-severe stenosis, persistent neurological symptoms, and failure of conservative treatment over 3 months, with a JOA score under 15 points or intermittent claudication at 100 m. This study included patients having LSS at a single vertebral level (L4/5).

RESULTS

Low back pain, buttock-leg pain, and numbness were significantly improved in terms of the VAS score from 3 months with both MEL and ME-MILD. In all periods, JOA scores over 3 years of follow-up were significantly higher than those obtained before surgery with both MEL and ME-MILD, and there were improvements of low back pain and walking function.

CONCLUSIONS

These observations demonstrate that ME-MILD is a safe and very effective minimally invasive technique for degenerative LSS, similar to MEL.

The influence of preoperative mental health on clinical outcomes after laminectomy in patients with lumbar spinal stenosis

OBJECTIVE

The influence of preoperative mental health on health-related quality of life (HRQOL) in patients with lumbar spinal stenosis (LSS) remains unclear. This study aims to investigate the influence of preoperative mental health HRQOL after laminectomy in patients with LSS.

PATIENTS AND METHODS

We retrospectively reviewed 122 patients who had lumbar spinous process splitting laminectomy (LSPSL) for LSS. We assessed clinical information; Japanese Orthopedic Association (JOA) score; numerical rating scale (NRS) for low back pain, for leg pain, and for leg numbness; Zurich Claudication Questionnaire (ZCQ); JOA Back Pain Evaluation Questionnaire (JOABPEQ); Roland-Morris Disability Questionnaire (RMDQ); and Short Form 8 (SF-8) as patient reported outcomes. Patients were divided into two groups (Group L ≤ 36.2 points and Group NL > 36.2 points) based on the results of the preoperative mental health (MH) score in SF-8 to examine the influence of MH in LSS. We compared the HRQOL between the two groups postoperatively.

RESULTS

The JOA score, NRS, and ZCQ score significantly improved after surgery. HRQOL outcomes including JOABPEQ, RMDQ, and SF-8 showed that the LSPSL improved not only the physical but also the mental function in patients with LSS. All HRQOL outcomes in Group L exhibited significantly worse scores preoperatively; however, no significant differences between two groups were found postoperatively.

CONCLUSIONS

LSPSL greatly reduced low back pain, leg pain, and leg numbness. LSPSL resulted in a significant improvement based on HRQOL questionnaires even in patients with preoperative depressive mood. Not only the physical status but also the mental health may improve after LSPSL even in patients with LSS with a depressive mood preoperatively.

Nonsurgical integrative Korean Medicine treatment of discal cyst: A case report and a retrospective chart review analysis

RATIONALE

Discal cysts are rare lesions characterized by pain caused by neurogenic compression with similar symptoms as those of disc herniation. This study aims to report the spontaneous regression of discal cyst achieved through nonsurgical integrative Korean Medicine treatment and the clinical epidemiological features of discal cyst cases collected from 4 institutions.

PATIENT CONCERNS

A 31-year-old woman had low back pain and radiating pain equivalent to a numeral rating scale (NRS) of 8 and had limitations in daily work and activities.

DIAGNOSES

The patient was diagnosed as having discal cysts that compressed the left S1 based on findings of L-spine magnetic resonance imaging (MRI) performed at our hospital.

INTERVENTIONS

The patient received nonsurgical Korean Medicine treatment and after 24 days of treatment in the hospital, she underwent 16 additional treatments as an outpatient.

OUTCOMES

Spontaneous regression was confirmed in the L-spine MRI follow-up at 36 days and 99 days after the initial test, and the patient underwent once-a-week follow up to examine NRS, Oswestry Disability Index (ODI), EuroQol-5 Dimensions (EQ-5D), and fear-avoidance beliefs questionnaire (FABQ) after 4 weeks, and 2, 3, and 6-month follow-ups after that. The patient was discharged in a painless condition, and she was able to carry on for 5 months without increased pain.

LESSONS

Discal cysts are more rapid progress than disc herniation, it seems valid to attempt nonsurgical treatment. Epidemiologically, this is the first study to present the clinical epidemiological characteristics of discal cysts, it would provide valuable information to clinicians who treat and study discal cysts.

Surgical Treatment of Lumbar Spinal Discal Cyst: Is It Enough to Remove the Cyst Only without Following Discectomy?

Discal cysts are a rare cause of low back pain and radiculopathy with unknown pathophysiologic mechanism. Associated symptoms are difficult to distinguish from those caused by extruded discs and other spinal canal lesions. Most discal cysts are treated surgically, but it is unclear whether the corresponding intervertebral disc should be excised along with cyst. We conducted a retrospective clinical review of 27 patients who underwent discal cyst excision at our institution between 2000 and 2017. The mean follow-up period was 63.6 months. We recorded symptoms, radiographs, operative findings, postoperative complications, and short- and long-term outcomes. Structured outcome assessment was based on Numeric Rating Scale (NRS) for pain intensity, Oswestry disability index, and Macnab classification. All patients underwent partial hemilaminectomy and microscopic cyst resection without discectomy. All patients had preoperative back or leg pain. Other preoperative clinical features included motor weakness, neurogenic intermittent claudication, and cauda equina syndrome. After surgery, NRS scores of back and leg pain decreased. The other symptoms also improved. During long-term follow-up, patients reported no restrictions on daily life activities, and were satisfied with our intervention. There were no cases of cyst recurrence. We conducted a review of the literature on lumbar discal cysts published before January, 2018. Including our cases, 126 patients were described. We compared two surgical modalities—cystectomy with and without discectomy—to elucidate both effectiveness and long-term complications. We found that microsurgical cystectomy without corresponding discectomy is an effective surgical treatment for lumbar discal cysts, and is associated with a low recurrence rate.

Impact of sagittal spinopelvic alignment on clinical outcomes and health-related quality of life after decompression surgery without fusion for lumbar spinal stenosis

OBJECTIVE

Patients with lumbar spinal stenosis (LSS) tend to bend forward to relieve neurological symptoms. They therefore have a positive sagittal vertical axis (SVA). The importance of the SVA value is well known in the field of adult spinal deformity; however, little is known about its impact on LSS. The authors sought to investigate the impact of sagittal spinopelvic alignment on clinical outcome and health-related quality of life (HRQOL) after decompression surgery for LSS.

METHODS

The authors retrospectively reviewed 83 patients who underwent lumbar decompression without fusion between January 2014 and September 2015 with a minimum follow-up of 2 years. Standing whole-spine radiographs were examined preoperatively and at final follow-up. Based on the SVA, patients were allocated to a sagittal balance group (group B; SVA < 50 mm) or a sagittal imbalance group (group I; SVA ≥ 50 mm). The authors compared the groups using Japanese Orthopaedic Association (JOA), Zurich Claudication Questionnaire (ZCQ), Roland-Morris Disability Questionnaire (RMDQ), and the 8-item Short Form Health Survey (SF-8) scores.

RESULTS

Preoperative groups B (group pre-B) and I (group pre-I) included 58 and 25 patients, respectively. Preoperative sagittal malalignment had negative effects on the JOA score recovery rate, postoperative ZCQ physical function domain score, and numeric rating scale (NRS) score of postoperative low-back pain (LBP), but no significant effects were observed for RMDQ and SF-8 domain scores. Postoperatively, groups B (group post-B) and I (group post-I) included 60 and 23 patients, respectively. Group post-I had a significantly worse JOA score recovery rate, postoperative symptom severity domain score in the ZCQ, and NRS score for postoperative LBP. Similarly, the postoperative RMDQ score and the Physical Component Summary score of the SF-8 were significantly worse in group post-I.

CONCLUSIONS

Positive SVA had significantly negative effects on clinical outcome and HRQOL in LSS patients after lumbar decompression surgery.

A Rare Case of a Discal Cyst Following Percutaneous Endoscopic Lumbar Discectomy via a Transforaminal Approach

A discal cyst is a rare lesion that causes low back pain and radiculopathy of the lower extremities. There are several reports of discal cysts occurring after surgery, but data are limited on their occurrence after percutaneous endoscopic discectomy (PED). A 21-year-old man with disc herniation at the L4-L5 disc level underwent PED via a transforaminal approach. The immediate postoperative course was uneventful and his symptoms were relieved. Six weeks after surgery, low back pain and mild pain in the left thigh recurred. Magnetic resonance imaging (MRI) revealed a cystic lesion adjacent to the left side of the L4-L5 intervertebral disc. Conservative treatment was ineffective, so we reoperated using PED with the same approach. Pain improved and MRI revealed disappearance of the cystic lesion. When symptoms relapse after PED, it is necessary to consider the occurrence of a cyst.

Lumbar Spinal Fusion Affects Sitting Disability on the Floor

Background

Lumbar spinal fusion is a standard of care for certain lumbar spinal diseases. However, its impact on sitting, especially on the floor, has not been assessed, even in the countries where people usually sit on the floor instead of using a chair.

Methods

A total of 100 Korean patients who underwent lumbar spinal fusion and 47 patients who underwent decompression surgery were enrolled. In a postoperative Oswestry Disability Index (ODI) questionnaire, an additional section 11 (Sitting on the Floor) was inserted, in which the phrase "sitting in a chair" of section 5 was replaced with "sitting on the floor." The ODI scores were calculated twice using either the section with "sitting in a chair" or the section with "sitting on the floor" and comparing the two.

Results

In the fusion group, the mean postoperative ODI calculated with "sitting on the floor" is significantly worse than that with "sitting in a chair" (P < .0001). This difference was the same regardless of whether the fusion was done at a single level (P < .0001) or 2 or more levels (P = .006) or whether location was at L4-L5 (P = .002) or L5-S1 (P = .02) in a single-level fusion. The scores of the decompression group showed no difference. Though preoperative and postoperative ODI showed no difference between groups, the postoperative ODI using "sitting on the floor" was significantly worse in the fusion group than the decompression group (P = .009).

Conclusion

ODI scores using "sitting on the floor" after lumbar fusion were significantly worse than those with "sitting in a chair." A sitting disability on the floor after lumbar arthrodesis has not been appreciated adequately so far and should be seriously considered if a lumbar arthrodesis is planned in a society where people's usual style of sitting is on the floor.

Redefining the Evolution of Spinal Discal Cyst Under Percutaneous Endoscopy: Report of Two Cases

Discal cyst has been recognized as a distinct cause of back pain and radiculopathy. The clinical features are similar to other pathologies as disc prolapse and stenosis. Various treatment modalities have been described, ranging from nerve blocks to surgical excision. There are scarce reports on the endoscopic appearance of discal cysts. The present paper based on two cases operated by transforaminal and interlaminar endoscopy at our institute demonstrates the explicit intraoperative view and different pathological components of discal cysts.

Discal Cyst of the Lumbar Spine: Case Report of a Rare Clinical Entity

Being a rare clinical entity, discal cyst presents indistinguishably from other causes of lower back pain and radiculopathy. It is an extremely rare pathology with unclear pathogenesis, indeterminate natural history with no consensus on the ideal management of the condition. We report a rare case of discal cyst in a patient who presented to our centre with localised low back pain and subsequently left sided radicular pain. With the aid of MRI and with clear surgical indication we proceeded with endoscopic removal of the cyst and intraoperatively confirmed its origin from the adjacent disc. The patient had immediate relief of his symptoms and no postoperative complications. We recommend that endoscopic surgery can be an effective alternative to conventional open surgery for discal cyst of the lumbar spine.

Extraforaminal Discal Cyst as Cause of Radiculopathy

We report the first extraforaminal location of a lumbar discal cyst. The patient was treated by hemilaminectomy, arthrectomy, cyst resection, and unilateral arthrodesis, achieving complete release of the nerve root. Extraforaminal lumbar discal cyst may represent an unexpected cause of sciatic pain with favorable outcome after surgical resection.

Acute Herniation of Nondegenerate Nucleus Pulposus: Acute Noncompressive Nucleus Pulposus Extrusion and Compressive Hydrated Nucleus Pulposus Extrusion

Acute herniation of nondegenerate nucleus pulposus material is an important and relative common cause of acute spinal cord dysfunction in dogs. Two types of herniation of nondegenerate or hydrated nucleus pulposus have been recognized: acute noncompressive nucleus pulposus extrusion (ANNPE) and acute compressive hydrated nucleus pulposus extrusion (HNPE). Spinal cord contusion plays an important role in the pathophysiology of both conditions. Sustained spinal cord compression is not present in ANNPE, whereas varying degrees of compression are present in HNPE. Although affected animals often present with severe neurologic signs, good outcomes can be achieved with appropriate treatment.

Ventral Lumbar Synovial Cyst Causing Cauda Equina Compression: Case Report and Literature Review

BACKGROUND

Juxtafacet spinal cysts are cystic synovial lesions that often are indistinguishable clinically or radiologically and require histopathology analysis to confirm the diagnosis. Lumbar synovial cysts usually arising from the synovium of the facet joints. They have been described posterolaterally or rarely in the posterior midline. However, we describe the first synovial cyst ventral to the dural sac.

CASE DESCRIPTION

We report a lumbar 3-4 lesion causing cauda equina compression in a 57-year-old man who presented with a 3-month history of low back pain and bilateral sciatica, intermittent urinary incontinence, and erectile dysfunction. Preoperative magnetic resonance imaging suggested prolapsed disc, after decompression, histological analysis of the fragment confirmed a synovial cyst.

CONCLUSIONS

Hitherto synovial cysts have not been reported anterior to the dural sac. We describe a lumbar ventral cystic mass with cauda equina compression that mimicked a disc prolapse due to synovial metaplasia. The patient had urgent decompression with subsequent resolution of the symptoms.

Different operative findings of cases predicted to be symptomatic discal pseudocysts after percutaneous endoscopic lumbar discectomy

Percutaneous endoscopic lumbar discectomy (PELD) is a minimally invasive treatment for lumbar disc herniation (LDH). This report focused on one of the rare complications of PELD: symptomatic postoperative discal pseudocyst (PDP). A 27-year-old male patient (case 1) presented with recurrent radiculopathy in his left leg. Twenty days previously, he had undergone PELD for left L4/5 LDH and his symptoms temporarily improved. A 14-year-old female patient (case 2) also developed recurrent pain in her left leg. Thirty days previously, she had undergone PELD for left L4/5 LDH and her symptoms disappeared. On the basis of the finding of an expandable round lesion at the evacuated sites of LDH on magnetic resonance imaging (MRI), with low intensity of T1-weighted imaging and high intensity on T2-weighted imaging, we predicted symptomatic PDP in both cases. Given the progressive leg pain in both cases, surgical treatments were adopted (case 1: microendoscopic discectomy, case 2: PELD). During the operation, we confirmed that case 1 was a simple recurrence of LDH and case 2 was symptomatic PDP. Previous studies on symptomatic PDP included cases diagnosed without operative findings. Therefore, it should be carefully considered that such cases might be a simple recurrence of LDH.

Canine acute cervical myelopathy: Hydrated nucleus pulposus extrusion or intraspinal discal cysts?

OBJECTIVE

To differentiate between hydrated nucleus pulposus extrusion and ventral intraspinal discal cysts in dogs.

STUDY DESIGN

Prospective case series.

ANIMALS

Twenty dogs with acute onset of cervical myelopathy due to hydrated nucleus pulposus extrusion or ventral intraspinal discal cysts.

METHODS

Clinical and magnetic resonance (MR) imaging findings, outcome after surgical treatment, cytologic and histologic findings of compressive material were taken into account. Comparisons and considerations were done between findings reported herein and what was previously described as suspected hydrated nucleus pulposus extrusion and intraspinal cysts.

RESULTS

All dogs were presented with acute onset of cervical myelopathy. MR imaging showed compressive cervical myelopathy at C2-C3 (n = 1), C3-C4 (n = 6), C4-C5 (n = 8), and C5-C6 (n = 5) intervertebral disc spaces, due to extradural material suggestive of either partially hydrated nucleus pulposus extrusion or intraspinal discal cyst, with T2 hyperintense and T1 iso-hypointense signal and variable contrast enhancement after gadolinium injection. All dogs were treated surgically by ventral slot (n = 15) or dorsolateral hemilaminectomy (n = 5). All dogs had a favorable outcome and regained a normal gait. The extradural material collected at surgery varied from liquid to more obvious gelatinous material. Cytologic or histologic examination of the material revealed similar findings for all dogs, compatible with partially degenerated nucleus pulposus.

CONCLUSIONS

Dogs with acute onset of compressive cervical myelopathy due to extradural material resembling human intraspinal cysts on MR images are most likely to have extrusion of partially degenerated nucleus pulposus and should be treated accordingly.

Transition of a herniated lumbar disc to lumbar discal cyst: A case report

Background:

Another rare cause of lower back pain with radiculopathy is the discal cyst. It is believed to arise from degeneration of a herniated disc, although many other theories of its origin have been proposed. Here, we report a patient with lower back pain/radiculopathy attributed originally to a herniated lumbar disc, which transformed within 6 months into a discal cyst.

Case Description:

A 42-year-old male had a magnetic resonance (MR) documented herniated lumbar disc at the L4-5 level. It was managed conservatively for 6 months, after which symptoms recurred and progressed. The follow-up MR study revealed a discal cyst at the L4-5 without residual herniated disc. Of interest, the cyst communicated with the L4-5 intervertebral disc, which was herniated under the posterior longitudinal ligament and the disc space. During surgery, the cyst was completely removed, and his symptoms/signs resolved.

Conclusion:

A discal cyst develops as pathological sequelae of a degenerated herniated disc. Although rare, these lesions must be considered among the differential diagnoses in young patients with radicular back pain. MR study clearly documents these lesions, and surgical excision of the cyst is the treatment of choice.

Uncommon Manifestations of Intervertebral Disk Pathologic Conditions

Beyond the familiar disk herniations with typical clinical features, intervertebral disk pathologic conditions can have a wide spectrum of imaging and clinical manifestations. The goal of this review is to illustrate and discuss unusual manifestations of intervertebral disk pathologic conditions that radiologists may encounter, including disk herniations in unusual locations, those with atypical imaging features, and those with uncommon pathophysiologic findings. Examples of atypical disk herniations presented include dorsal epidural, intradural, symptomatic thoracic (including giant calcified), extreme lateral (retroperitoneal), fluorine 18 fluorodeoxyglucose-avid, acute intravertebral (Schmorl node), and massive lumbar disk herniations. Examples of atypical pathophysiologic conditions covered are discal cysts, fibrocartilaginous emboli to the spinal cord, tiny calcified disks or disk-level spiculated osteophytes causing spinal cerebrospinal fluid (CSF) leak and intracranial hypotension, and pediatric acute calcific discitis. This broad gamut of disease includes a variety of sizes of disk pathologic conditions, from the tiny (eg, the minuscule calcified disks causing high-flow CSF leaks) to the extremely large (eg, giant calcified thoracic intradural disk herniations causing myelopathy). A spectrum of clinical acuity is represented, from hyperacute fibrocartilaginous emboli causing spinal cord infarct, to acute Schmorl nodes, to chronic intradural herniations. The entities included are characterized by a range of clinical courses, from the typically devastating cord infarct caused by fibrocartilaginous emboli, to the usually spontaneously resolving pediatric acute calcific discitis. Several conditions have important differential diagnostic considerations, and others have relatively diagnostic imaging findings. The pathophysiologic findings are well understood for some of these entities and poorly defined for others. Radiologists' knowledge of this broad scope of unusual disk disease is critical for accurate radiologic diagnoses. Online supplemental material is available for this article. (©)RSNA, 2016.

Successful Treatment of a Symptomatic Discal Cyst by Percutaneous C-arm Guided Aspiration

Although discal cysts are a rare cause of low back pain and radiculopathy. Currently, surgical excision is usually the first-line treatment for discal cysts. However, alternative treatment methods have been suggested, as in some cases symptoms have improved with interventional therapies. A 27-year-old man presented with an acute onset of severe pain, and was found to have a discal cyst after an open discectomy. The patient underwent cyst aspiration and steroid injection through the facet joint under C-arm guidance. After the procedure, the patient's pain improved to NRS 0-1. On outpatient physical examination 1 week, and 1 and 3 months later, no abnormal neurological symptoms were present, and pain did not persist; thus, follow-up observation was terminated. When a discal cyst is diagnosed, it is more appropriate to consider interventional management instead of surgery as a first-line treatment, while planning for surgical resection if the symptoms do not improve or accompanying neurologic deficits progress.