Full-endoscopic technique for posterior fossa decompression in Chiari malformation type I: An anatomical feasibility study in human cadavers.

Although endoscope-assisted techniques have been described, a full-endoscopic approach is yet to be performed for posterior fossa decompression (PFD) in Chiari malformation type I (CM-I). This study aims to describe the full-endoscopic PFD technique and evaluate its feasibility. Five fresh-frozen anonymized adult human cadavers were operated on using an endoscope with an oval shaft cross-section with a diameter of 9.3 mm, a working length of 177 mm, and a viewing angle of 20°. It also had an eccentric working channel with a diameter of 5.6 mm, a light guide, a sheath for continuous irrigation, and a rod lens system. The instruments were introduced from the working channel. Posterior craniocervical structures were dissected, and PFD was achieved. The planned steps were performed in all five cadavers. The endoscope was introduced to the posterior craniocervical region, dissecting the structures to easily expose the suboccipital bone and C1 posterior arch. Important structures, such as the C1 posterior tubercle, rectus capitis posterior minor muscles, and posterior atlantooccipital membrane, were used as landmarks. PFD was feasible even with the dural opening. Using the full-endoscopic approach, posterior craniocervical structures can be reached, and PFD can be performed successfully. The instruments used are well-defined for spinal usage; thus, this full-endoscopic technique can be widely used in the surgical treatment of patients with CM-I.

Percutaneous Radiofrequency Disc Decompression: A Study of 27 Patients.

BACKGROUND: Percutaneous radiofrequency nucleoplasty is a true minimally invasive technique for treatment for radiculopathy caused by contained disc protrusions. This minimally invasive procedure uses controlled thermoablation for reducing the intervertebral disc and decompressing the lumbar nerve root. Material and Methods: Our study is a prospective analysis of 27 patients aged from 30 to 64 years with lumbar disc protrusion who were treated with percutaneous radiofrequency disc decompression (PRFD) between May 2018 and May 2019. Clinical follow-up was reported at 1 month, 3 months, and 6 months. The outcomes were assessed using a visual analog scale (VAS) and MacNab score. RESULTS: Of the 27 patients, 14 were female and 13 were male. Their mean age was 53 ± 2 years. In all 27 patients, percutaneous radiofrequency nucleotomy was performed. An excellent outcome as reflected by MacNab score was observed in 17 patients (63%), a good outcome in 8 patients (29.7%), and a poor outcome in 2 patients (7.3%). Prior to treatment, the average back and leg VAS scores were 7.95 and 7.82, respectively. At sixth month follow-up, the back and leg VAS scores were reduced to 3.17 and 3.04, respectively. Patients with a poor outcome developed early recurrent disc prolapse and required endoscopic discectomy. CONCLUSION: PRFD is a safe and effective treatment of contained disc protrusion. PRFD is a good alternative to surgery. These procedures significantly increase quality of life in patients with lumbar radiculopathy.

[The trend towards full-endoscopic decompression : Current possibilities and limitations in disc herniation and spinal stenosis]. / Der Trend zu vollendoskopischen Dekompressionen : Aktuelle Möglichkeiten und Grenzen bei Bandscheibenvorfall und Spinalkanalstenose.

BACKGROUND: The most frequent causes of degenerative constrictions of the spinal canal are disk herniations and spinal stenoses. The lumbar and cervical spine is the most affected. SURGICAL PROCEDURES: After conservative treatments have been exhausted, surgical intervention may be necessary. Today, microsurgical decompression is regarded as the standard procedure in the lumbar region, while in the cervical spine, microsurgical anterior decompression and fusion are standard. Full-endoscopic techniques for decompression are becoming increasingly widespread worldwide. The development of various surgically created approaches and appropriate instrument sets have made the full-endoscopic operation of disk herniations and spinal stenosis possible. This development has also permitted resection of soft disk herniations in the cervical spine. The use of the approaches depends on anatomical and pathological inclusion and exclusion criteria. RESULTS: The clinical results of standard procedures have been achieved, which must be regarded as a minimum criterion for the introduction of new technologies. On the basis of EBM criteria, it can be established that using the full-endoscopic techniques developed, adequate decompression is achieved in the defined indications with reduced traumatization, improved visibility conditions, and positive cost benefits. Today, full-endoscopic operations may be regarded as an expansion and alternative within the overall concept of spinal surgery.

[Minimally invasive decompression techniques for spinal cord stenosis]. / Minimal-invasive Dekompressionsverfahren der Spinalkanalstenose.

BACKGROUND: Lumbar spinal canal stenosis is frequently found among elderly patients and significantly limits their quality of life. Non-surgical therapy is an initial treatment option; however, it does not eliminate the underlying pathology. Surgical decompression of the spinal canal has now become the treatment of choice. OBJECTIVE: Minimalization of surgical approach strategies with maintaining sufficient decompression of the spinal canal and avoiding disadvantages of macrosurgical techniques, monolateral paravertebral approach with bilateral intraspinal decompression, specific surgical techniques. MATERIALS AND METHODS: Minimally invasive decompression techniques using a microscope or an endoscope are presented and different surgical strategies depending on both the extent (mono-, bi-, and multisegmental) and the location of the stenosis (intraspinal central, lateral recess, foraminal) are described. RESULTS: Minimally invasive microscopic or endoscopic decompression procedures enable sufficient widening of the spinal canal. Disadvantages of macrosurgical procedures (e. g., postoperative instability) can be avoided. The complication spectrum overlaps partially with that of macrosurgical interventions, albeit with significantly less marked severity. Subjective patient outcome is clearly improved. CONCLUSIONS: Referring to modern minimally invasive decompression procedures, surgery of lumbar spinal canal stenosis represents a rational and logical treatment alternative, since causal treatment of the pathology is only possible with surgery.

AOSpine Consensus Paper on Nomenclature for Working-Channel Endoscopic Spinal Procedures.

STUDY DESIGN: International consensus paper on a unified nomenclature for full-endoscopic spine surgery. OBJECTIVES: Minimally invasive endoscopic spinal procedures have undergone rapid development during the past decade. Evolution of working-channel endoscopes and surgical instruments as well as innovation in surgical techniques have expanded the types of spinal pathology that can be addressed. However, there is in the literature a heterogeneous nomenclature defining approach corridors and procedures, and this lack of common language has hampered communication between endoscopic spine surgeons, patients, hospitals, and insurance providers. METHODS: The current report summarizes the nomenclature reported for working-channel endoscopic procedures that address cervical, thoracic, and lumbar spinal pathology. RESULTS: We propose a uniform system that defines the working-channel endoscope (full-endoscopic), approach corridor (anterior, posterior, interlaminar, transforaminal), spinal segment (cervical, thoracic, lumbar), and procedure performed (eg, discectomy, foraminotomy). We suggest the following nomenclature for the most common full-endoscopic procedures: posterior endoscopic cervical foraminotomy (PECF), transforaminal endoscopic thoracic discectomy (TETD), transforaminal endoscopic lumbar discectomy (TELD), transforaminal lumbar foraminotomy (TELF), interlaminar endoscopic lumbar discectomy (IELD), interlaminar endoscopic lateral recess decompression (IE-LRD), and lumbar endoscopic unilateral laminotomy for bilateral decompression (LE-ULBD). CONCLUSIONS: We believe that it is critical to delineate a consensus nomenclature to facilitate uniformity of working-channel endoscopic procedures within academic scholarship. This will hopefully facilitate development, standardization of procedures, teaching, and widespread acceptance of full-endoscopic spinal procedures.

Decompression for cervical disc herniation using the full-endoscopic anterior technique.

OBJECTIVE: Resection of a cervical disc herniation using a full-endoscopic technique with an anterior approach. INDICATION: Fresh disc herniation with monoradicular symptoms in the upper extremity. CONTRAINDICATIONS: Pure neck pain, cervical myelopathy, older and calcified disc herniations, higher grade of instability and deformity. SURGICAL TECHNIQUE: Introduction of a guidewire and dilatator to a cervical disc using an anterior approach. Under full-endoscopic view, preparation of the posterior parts of the annulus, opening of the annulus and posterior longitudinal ligament and resection of the herniated fragment from the epidural space. POSTOPERATIVE MANAGEMENT: Immediate mobilisation, isometric/coordinative exercises, functional exercises from week 3, building up strength from week 6. RESULTS: A total of 120 patients were operated using the full-endoscopic or microsurgically assisted technique and were followed up for 24 months. Significant improvement was achieved in both groups. The group of full-endoscopic operated patients returned to work significantly earlier and 89% of all patients would undergo the operation again.

[Decompression for cervical disc herniation using the full-endoscopic anterior technique - German version]. / Dekompression beim zervikalen Bandscheibenvorfall in vollendoskopischer, ventraler Technik.

OBJECTIVE: Resection of a cervical disc herniation using a full-endoscopic technique with an anterior approach. INDICATION: Fresh disc herniation with monoradicular symptoms in the upper extremity. CONTRAINDICATIONS: Pure neck pain, cervical myelopathy, older and calcified disc herniations, higher grade of instability and deformity. SURGICAL TECHNIQUE: Introduction of a guidewire and dilatator to a cervical disc using an anterior approach. Under full-endoscopic view, preparation of the posterior parts of the annulus, opening of the annulus and posterior longitudinal ligament and resection of the herniated fragment from the epidural space. POSTOPERATIVE MANAGEMENT: Immediate mobilisation, isometric/coordinative exercises, functional exercises from week 3, building up strength from week 6. RESULTS: A total of 120 patients were operated using the full-endoscopic or microsurgically assisted technique and were followed up for 24 months. Significant improvement was achieved in both groups. The group of full-endoscopic operated patients returned to work significantly earlier and 89% of all patients would undergo the operation again.

Full-endoscopic posterior foraminotomy surgery for cervical disc herniations.

OBJECTIVE: Surgery for cervical disc herniation with full-endoscopic posterior access. INDICATIONS: Cervical disc herniation and neuroforaminal pathology with radicular symptoms. CONTRAINDICATIONS: Neck pain alone, cervical myelopathy or pathologies with central nervous system symptoms, instabilities requiring correction/instabilities. SURGICAL TECHNIQUE: Introduction of a surgical tube to the facet joint at the level to be operated on. Resection of bony and ligamentous parts of the cervical spinal canal under endoscopic guidance. Visualisation of the disc herniation and decompression of the neural structures. POSTOPERATIVE MANAGEMENT: Immediate mobilisation, specific rehabilitative physiotherapy depending on pre-existing neurological deficits. RESULTS: A total of 87 patients underwent full-endoscopic posterior surgery and were followed over a period of 2 years. Significant improvement was observed. No serious complications occurred. In all, 5 patients underwent revision in the follow-up period. Of the patients, 93% would undergo the procedure again.

[Decompression of lumbar lateral spinal stenosis: full-endoscopic, interlaminar technique]. / Dekompression der lumbalen Rezessusstenose : Endoskopische, interlaminäre Technik.

OBJECTIVE: Decompression in lumbar recess stenosis in a full-endoscopic technique using an interlaminar approach. INDICATIONS: Lumbar recess stenosis due to ligamentous, osseous, discogenic compression, and/or juxta-facet cysts. CONTRAINDICATIONS: Pure back pain, instability/deformity requiring correction, pure foraminal stenosis. SURGICAL TECHNIQUE: Introduction of a surgical sleeve to the intralaminar window. Endoscopic resection of compressing bony/ligamentary structures and also of osteophytes or parts of annulus. POSTOPERATIVE MANAGEMENT: Immediate mobilization, isometric/coordination exercises, functional exercises from week 3, building up strength from week 6. RESULTS: A total of 192 patients underwent full-endoscopic surgery or microsurgery and were followed up over a minimum of 2 years. A significant improvement was revealed. Serious complications occurred in 5% and were significantly reduced in the endoscopic group. Five patients were revised with decompression and/or fusion. Eighty-nine percent would undergo the operation again.

[Differential diagnosis of back pain in patients with ankylosing spondylitis: instable cervical spine fracture]. / Differenzialdiagnose Rückenschmerz bei Patienten mit Spondylitis ankylosans: instabile Halswirbelsäulenfraktur.

HISTORY AND ADMISSION FINDINGS: A 65-year-old patient with longstanding ankylosing spondylitis (AS) complained of persistent pain in the right shoulder and the neck; elevation of the shoulder was impaired. The symptoms had started a week before admission after a fall. Physical examination revealed generally decreased mobility of an already hyperkyphotic cervical spine (CS) and decreased thoracic excursion. The paravertebral muscles were stiff . CLINICAL INVESTIGATIONS: Because of the trauma extensive imaging procedures with conventional radiographs, magnetic resonance imaging (MRI) and computed tomography (CT) of the CS were performed. These showed a compression fracture of C5, detachment of the dorsal and ventral ligaments and a ventral dislocation of C4 with dislocation (Type C fracture). TREATMENT AND COURSE: After immediate consultation of the cooperating center for spinal surgery corpectomy of C5 and ventral fusion of C3-7 were performed on the same day, together with a dorsal transpedicular fusion. During the imaging procedures symptoms of a beginning paraplegia occurred. After successful surgery and early postoperative rehabilitation, the patient was discharged to an in-patient rehabiltation unit. At discharge, there was but a slight paresis of the right arm. CONCLUSION: Patients with AS and advanced spinal ankylosis are at increased risk of vertebral fracture after minor accidents. Regardless of the initial report of clinical symptoms it is mandatory to perform appropriate imaging procedures usually including MRI.

A new full-endoscopic technique for cervical posterior foraminotomy in the treatment of lateral disc herniations using 6.9-mm endoscopes: prospective 2-year results of 87 patients.

Anterior cervical decompression and fusion (ACDF) is the standard procedure for operation of cervical disc herniations with radicular arm pain. Mobility-preserving posterior foraminotomy is the most common alternative in the case of a lateral localization of the pathology. Despite good clinical results, problems may arise due to traumatization of the access. Endoscopic techniques are considered standard in many areas, since they may offer advantages in surgical technique and rehabilitation. These days, all disc herniations of the lumbar spine can be operated in a full-endoscopic technique. The objective of this prospective study was to examine the technical possibilities of full-endoscopic posterior foraminotomy in the treatment of cervical lateral disc herniations. 87 patients were followed for 2 years. The results show that 87.4% no longer have arm pain and 9.2% have only occasional pain. The decompression results were equal to those of conventional procedures. The operation-related traumatization was reduced. The recurrence rate was 3.4%. No serious surgical complications occurred. The recorded results show that the full-endoscopic posterior foraminotomy is a sufficient and safe supplement and alternative to conventional procedures when the indication criteria are fulfilled. At the same time, it offers the advantages of a minimally invasive intervention.

A New full-endoscopic technique for the interlaminar operation of lumbar disc herniations using 6-mm endoscopes: prospective 2-year results of 331 patients.

Even with good results, conventional disc operations may result in consecutive damage due to traumatisation. Endoscopic techniques have become the standard in many areas because of the advantages they offer in surgical technique and in rehabilitation. The transforaminal operation is the most common full-endoscopic procedure in surgery of the lumbar spine. It is frequently necessary to reach the spinal canal directly in order to achieve sufficient resection of lumbar disc herniations. Even in using a lateral approach, the authors recognise the clear limitations of the transforaminal procedure. The objective of this prospective study was to examine the technical possibility of a full-endoscopic interlaminar access. The focus was on questions of sufficient decompression, as well as advantages and disadvantages of the minimally invasive procedure. 331 patients were followed for 2 years. The results show that 82 % reported no longer having leg pain, and 13 % had only occasional pain. The decompression results are equivalent to those of conventional procedures. Traumatisation of both the access pathway and the spinal canal structures was reduced. Epidural scarring was minimised. The recurrence rate was 2.4 %. No serious surgical complications were observed. The authors view the technique described, which offers the advantage of a truly minimally invasive procedure, as a sufficient and safe alternative to conventional procedures, when the appropriate indication criteria are heeded. There are technical problems because of the small instruments. In conjunction with the transforaminal procedure, this is an expansion of the spectrum for full-endoscopic surgery of lumbar disc herniations.

Application of holmium:YAG laser in epiduroscopy: extended practicabilities in the treatment of chronic back pain syndrome.

OBJECTIVE: Minimally invasive and endoscopic techniques offer advantages in the treatment of chronic back pain syndrome and may provide for expanded indications and visualization. Epiduroscopy for the visualization of the epidural space still is burdened with technical problems. The mechanical instruments now available, coupled with the narrow working canal, result in marked limitations. The aim of this study was to assess the possibilities and technical requisites for the use of the holmium:YAG laser in lumbar epiduroscopy. BACKGROUND DATA: Epiduroscopy has been used for visualization of the lumbar epidural space since the 1930s. Studies have been performed to evaluate the effects and possibilities of epiduroscopy in chronic back pain. Most of them only describe the anatomical aspects. MATERIALS AND METHODS: Forty-seven patients were epiduroscopied and treated, for findings of corresponding epidural adhesions, with the holmium:YAG laser. The examinations concentrated on the general applicability of the holmium:YAG laser in epiduroscopy and the technical parameters necessary for this procedure. The clinical evaluation of therapy was made prospectively in comparison with the preoperative status and compared to already recorded groups in previous studies. RESULTS: Bending behavior without negative impact of the epiduroscope was only attained with laser fibers less than 300 microm, so a fiber with a diameter of 265 microm was used as the standard. The minimum energy output of the laser required for an adequate ablative effect was 0.8 J at a frequency of 8 Hz. The total energy output was 0.256-1.4 kJ. Complications did not occur intraoperatively nor following the procedure. The follow-up examinations showed no deterioration of the complaints in any patient. There was no occurrence of relevant laser-related edemas or adhesions. The proportion of painful conditions that could be positively influenced corresponded to that in a control group treated only by mechanical means. CONCLUSION: The results show that the holmium:YAG laser considerably expands therapeutic possibilities and aids in solving the technical problems of epiduroscopy. No negative effects occurred when the laser is used.

Endoscopic surgery of the lumbar epidural space (epiduroscopy): results of therapeutic intervention in 93 patients.

Determination and therapy of the underlying pathology in chronic pain syndrome in the lumbar spine is frequently difficult. Minimally invasive and microsurgical techniques may offer advantages. Epiduroscopy is available for visualization of the lumbar epidural space. 93 patients with chronic back-leg pain syndrome were epiduroscopically operated. When findings were appropriate, mechanical instruments and the holmium:YAG laser were applied therapeutically. 45.9 % of these patients presented with positive results in postoperative examination. Pathomorphological processes corresponding to the multifactorial pain processes, which escape detection in modern imaging procedures, can be diagnosed in the epidural space using epiduroscopy Therapeutic intervention is basically possible. However, use is limited due to technical difficulties. Navigation of the endoscope is especially limited in access via the hiatus sacralis.

[Epiduroscopic diagnosis and treatment of epidural adhesions in chronic back pain syndrome of patients with previous surgical treatment: first results of 31 interventions]. / Epiduroskopische Diagnostik und Therapie epiduraler Adhäsionen beim chronisch lumbalen Schmerzsyndrom des voroperierten Patienten: Erste Ergebnisse von 26 Interventionen.

AIM: Scars in the epidural space play an important role in the chronic lumbar pain syndrome of patients with previous surgical treatment. The results of surgical resection are frequently unsatisfactory. Discrepancies to imaging diagnostics are conspicuous. These are known from experience with endoscopic operations. Minimal adhesions may promote pain. Epiduroscopy is available for visualization of the epidural space. The objective of this study was to examine its possibilities in patients with previous surgical treatment. METHOD: 31 patients with chronic lumbar pain syndrome who had previously received surgical treatment were operated epiduroscopically. Mechanical instruments and the holmium:YAG laser were used for epidural adhesion. RESULTS: All patients showed adhesions. 24 patients also presented with adhesions on the contralateral side. There were marked discrepancies between imaging and intraoperative findings. The use of mechanical instruments was limited. The use of laser fibers resulted in greater possibilities. Back pain could be better influenced than leg pain. The procedure was limited by still-existing technical problems. CONCLUSION: Epiduroscopy offers a novel view of this compartment. Minimal adhesions which are not visible in imaging ean promote pain. They can be partially diagnosed and treated by epiduroscopy. There are still marked limitations to epiduroscopy due to technical problems. These must be minimized.