Full-Endoscopic Posterior Lumbar Interbody Fusion: A Review and Technical Note.

Remarkable innovations in spinal endoscopic surgery have broadened its applications over the past 20 years. Full-endoscopic fusions have been widely reported, and several full-endoscopic approaches for interbody fusion have been published. In general, full-endoscopic lumbar interbody fusion (LIF) is called Endo-LIF, and facet-preserving Endo-LIF through the transforaminal route is called trans-Kambin's triangle LIF, which has a relatively longer history than facet-sacrificing Endo-LIF via the posterolateral route. Both approaches can reduce intraoperative and postoperative bleeding. However, there is a higher risk of subsidence and exit nerve root injury. There is no direct decompression in either of the interbody fusions, and additional decompression is required if there is severe lumbar bony canal stenosis. However, the posterior interlaminar approach, which is a well-known standard in full-endoscopic spine surgery, has rarely been applied in the field of endoscopic lumbar fusion surgery. Full-endoscopic posterior LIF (FE-PLIF) via an interlaminar approach can accomplish direct decompression of bony canal stenosis and safe interbody fusion. FE-PLIF via an interlaminar approach demonstrated a longer operation time, less blood loss, and shorter hospitalization duration than minimally invasive transforaminal LIF. FE-PLIF, which can accomplish direct decompression for bony spinal canal stenosis, is superior to other Endo-LIFs. However, FE-PLIF requires technical dexterity to improve efficiency and reduce technical complexity.

Enhancing Transforaminal Full Endoscopic Discectomy: Efficacy of the Hand Down Outside-In (HDOI) Technique.

Endoscopic lumbar discectomy (ELD) is a key advancement in minimally invasive spinal surgery, particularly for lumbar disc herniation. Interlaminar endoscopic lumbar discectomy (IELD) and transforaminal endoscopic lumbar discectomy (TELD) are the two major methods used for FED. TELD, while less familiar to spine surgeons inexperienced in endoscopic surgery, presents challenges in visualizing the dura mater, a crucial aspect for reducing surgical complications. The hand down outside-in (HDOI) technique introduced by Dezawa enhances this visualization by positioning the cannula tip dorsally on the intervertebral disc and maneuvering it between the dura mater and disc to the spinal canal's midpoint. The cannula is then flipped to directly visualize the dura mater, enabling safe removal of the prolapsed disc material. A comparative study involving 20 patients treated from April 2020 to April 2022 examined the efficacy of the HDOI technique against conventional TELD. Each group, comprising ten patients, underwent ELD for lumbar disc herniation. While both groups showed similar improvements in clinical outcomes, as assessed using the Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) for pain, the HDOI group exhibited a 100% success rate for dura mater visualization, and this rate is significantly higher than the 60% observed in the conventional TELD group. Additionally, the time required for dura mater visualization was notably shorter for the HDOI technique. These results indicate that the HDOI technique not only enhances the safety and efficacy of TELD but may also encourage its wider use in clinical settings.

Histological analysis of nucleus pulposus tissue from patients with lumbar disc herniation after condoliase administration.

Background: Condoliase is an enzyme used as a treatment for lumbar disc herniation (LDH). This enzyme degrades chondroitin sulfate (CS) in the nucleus pulposus of the intervertebral disc (IVD). However, there are cases in which symptoms do not improve, despite condoliase administration. This study reports histological analysis of lumbar disc tissue of LDH patients who underwent surgery because condoliase had no therapeutic effect. Methods: Between March 2019 and August 2019, 12 LDH patients who underwent full endoscopic spine surgery (FESS) discectomy at the Dezawa Akira PED Clinic were the subjects of the study. There are two study groups: six cases underwent FESS after condoliase administration, while six underwent FESS without condoliase administration. The average duration from drug administration to surgery was 152 days. Herniated disc removed at surgery was evaluated by histological staining including immunohistochemistry by anti-CS antibodies. Results: Multiple large clusters (40-120 µm in diameter) were observed in the nucleus pulposus of those who received condoliase, but no clusters were observed in those who did not. The lumbar disc tissues, including the nucleus pulposus of recipients, were stained with anti-CS antibodies that recognize the CS unsaturated disaccharide, but non-administration tissue was not stained. These findings suggest that the enzyme acted on the nucleus pulposus, even in cases where symptoms were not improved by condoliase administration. Furthermore, there was no histological difference between stained images of the extracellular matrix in those who did or did not receive condoliase, suggesting that condoliase acted specifically on CS in the nucleus pulposus. Conclusions: We demonstrated that CS in the nucleus pulposus was degraded in patients in whom condoliase did not have a therapeutic effect. Moreover, condoliase acts in human IVD without causing necrosis of chondrocytes and surrounding tissues.

In Vitro Study of the Effects of Denosumab on Giant Cell Tumor of Bone: Comparison with Zoledronic Acid.

Giant cell tumor of bone (GCTB) is a locally aggressive primary bone tumor that contains numerous osteoclasts formed from marrow-derived precursors through receptor activator of nuclear factor κ-B ligand (RANKL), an osteoclast differentiation factor expressed in neoplastic cells of GCTB. Denosumab, a fully human monoclonal antibody targeting RANKL, has recently been used for the treatment of GCTB, and superior treatment effects have been reported. The aim of this work was to elucidate the mechanism of action of denosumab, and the differences between denosumab and zoledronic acid at the level of GCTB cells. We isolated GCTB cells from 3 patients and separated them into osteoclasts, osteoclast precursors and proliferating spindle-shaped stromal cells (the true neoplastic component), and examined the action of denosumab on differentiation, survival and bone resorption activity of osteoclasts. Denosumab and zoledronic acid inhibited osteoclast differentiation from mononuclear cells containing osteoclast precursors. Zoledronic acid inhibited osteoclast survival, whereas an inhibitory effect of denosumab on osteoclast survival was not observed. The inhibitory effect on bone resorption by both agents was confirmed in culture on dentin slices. Furthermore, zoledronic acid showed dose-dependent inhibition of cell growth of neoplastic cells whereas denosumab had no inhibitory effect on these cells. Denosumab has an inhibitory effect on osteoclast differentiation, but no inhibitory effects on survival of osteoclasts or growth of neoplastic cells in GCTBs.

Surgical treatment of a lumbar aneurysmal bone cyst using percutaneous endoscopic lumbar discectomy.

PURPOSE: Aneurysmal bone cysts of the lumbar spine are usually treated by curettage followed by bone or bioactive ceramics grafting. Here, we present the first case of an aneurysmal bone cyst of the lumbar spine treated by percutaneous endoscopic lumbar discectomy (PELD). METHODS: We describe the clinical characteristics of the patient including the radiological and pathological findings of the tumor and the surgical technique used. RESULTS: A 15-year-old boy presented with low back pain, and he was diagnosed with an aneurysmal bone cyst of the L3 vertebra based on radiological findings, including plain radiograph, computed tomography, and magnetic resonance imaging. The technique and equipment of PELD were used to perform curettage of the tumor cavity and fill it with hydroxyapatite granules. The skin incision was only 8 mm. The patient was discharged 1 day postoperatively and could walk without assistance. The postoperative course was uneventful and the symptoms improved following surgery. CONCLUSION: Endoscopic surgery via PELD can be a treatment option for ABCs of the lumbar spine.

Etiology of Adult-onset Stress Fracture in the Lumbar Spine.

STUDY DESIGN: This study was a case series. OBJECTIVE: The purpose of this paper was to present a case series of fresh stress fractures (spondylolysis) in the lumbar spines of adult athletes. SUMMARY OF BACKGROUND DATA: Lumbar spondylolysis is a stress fracture of the pars interarticularis, which is generally considered a disease of children or adolescence. There is only 1 case series written in English reporting on adult-onset fresh spondylolysis. METHODS: Eleven patients aged 20-27 years are included in this case series. A retrospective analysis was made of events that may cause stress fracture such as traumatic episodes or sports activities, spinal level, radiologic findings, stage of spondylolysis, treatment, and prognosis. RESULTS: Among the 11 patients, two had bilateral early-stage spondylolysis, 7 had unilateral early-stage spondylolysis and 2 had unilateral progressive-stage spondylolysis. Three occurred subsequent to a preexisting terminal-stage spondylolysis in the contralateral side, 1 occurred subsequent to a terminal-stage spondylolysis at the adjacent spinal level, and 1 occurred subsequent to a terminal-stage spondylolysis at a distant level. Thirteen pedicles adjacent to the pars interarticularis in the 11 patients showed bone marrow edema-like signal on magnetic resonance imaging. Six spondylolyses were found at L5, 2 each at L3 and L4, and 1 spondylolysis at L2. The 11 patients were divided into 4 groups according to suspected pathogenic mechanism: preexistent spondylolysis in the contralateral side, alteration of the athletic event, apparent traumatic episode, and others. Conservative treatment was prescribed for return to sports in all cases. Although 1 patient retired because of persistent low back pain, the remaining 10 patients returned to competition. CONCLUSIONS: Although lumbar spondylolysis is generally recognized to occur in childhood or adolescence, fresh lumbar spondylolysis should be included in the differential diagnosis of adult low back pain when patients are high-level athletes. Conservative treatment should be attempted for adult patients.

State of the art: Transforaminal approach for percutaneous endoscopic lumbar discectomy under local anesthesia.

Minimally invasive percutaneous endoscopic discectomy (PED) with a transforaminal approach under local anesthesia was started in the late 20th century. As the procedure requires a skin incision of only 8 mm, it is the least invasive disc surgery procedure at present, and owing to advances in instruments and optics, the use of this technique has gradually spread. In Japan, Dr. Dezawa from Teikyo University Mizonokuchi Hospital introduced this technique in 2003. Thanks to his efforts, the number of surgeons who can perform PED has increased, although the number of active PED surgeons is still only around 20. The first author (K.S.) started PED in 2010. In this review article, we explain the state-of-the-art PED transforaminal technique for minimally invasive disc surgery and present three successful cases.

Assessment of maximal insertional torque of cervical and thoracic screws during posterior spinal surgery.

STUDY DESIGN: Multicenter intraoperative biomechanical analysis. PURPOSE: This study aimed to assess the maximal insertional torque (MIT) of lateral mass screw (LMS) and pedicle screw (PS) in the cervical or thoracic vertebrae during surgery. METHODS: During posterior spinal fusion, cervical or thoracic multi-axial screws were placed at different cervical or thoracic levels and the MIT was recorded for each screw revolution using an analogue torque wrench. Screw number was as follows: 11 PS at C7, 134 LMS (C3-6) (Magerl technique, 70; Roy-Camille technique, 64), and 33 PS in the thoracic region. RESULTS: Average MIT values (cNm) were as follows: for PS (diameter: 3.5 mm) at C7, 45.3 ± 21.9 in men and 60.0 ± 20.1 in women (p=0.28); for Magerl screws, 69.0 ± 20.5 in men and 58.6 ± 15.7 in women (p=0.13); and for Roy-Camille screws, 51.0 ± 17.9 in men and 42.4 ± 15.9 in women (p=0.52). The average MIT for Magerl screws was significantly higher than that for Roy-Camille screws in men and women (both p<0.01). CONCLUSIONS: Intraoperative insertional torque could be a good indicator to evaluate the purchase and help guide decisions on screw type and insertion technique. Further postoperative assessments with sequential X-rays are needed to reveal the significance of MIT during posterior spinal fusion.

Persistent tight hamstrings following conservative treatment for apophyseal ring fracture in adolescent athletes: critical appraisal.

Apophyseal ring fracture is a unique disease in children and adolescents. Its clinical features include low back pain, sciatica, paravertebral muscle spasm and tenderness, restricted back motion, neurological symptoms, and tight hamstrings. For all athletes, body flexibility is one of the most important factors for better performance. Therefore, persistent tight hamstrings has a negative influence on athletic performance. In this report, we present two adolescent athletes with apophyseal ring fracture treated successfully by conservative treatment for severe low back pain (LBP) and leg pain, despite having persistent tight hamstrings for more than one year. Unlike herniated nucleus pulposus, bony fragments in the spinal canal never disappear. Although conservative treatment can alleviate LBP and leg pain, surgical removal of fragments is considered when symptoms such as tight hamstrings and restricted lumbar motion due to canal stenosis are found, particularly in athletes.

Comparison of organic electroluminescence and liquid crystal displays for clinical utility in orthopedic endoscopic surgery.

INTRODUCTION: Organic electroluminescence displays (OELD) use organic materials that self-emit light with the passage of an electric current. OELD provide high contrast, excellent color reproducibility at low brightness, excellent video images, and less restricted viewing angles. OELD are thus promising for medical use. This study compared the utility of an OELD with conventional liquid crystal displays (LCD) for imaging in orthopedic endoscopic surgery. METHODS: One OELD and two conventional LCD that were indistinguishable in external appearance were used in this study. Images from 18 patients were displayed simultaneously on three monitors and evaluated by six orthopedic surgeons with extensive surgical experience. Images were shown for 2 min, repeated twice, and viewed from the front and side (diagonally). Surgeon rated both clinical utility (12 parameters) and image quality (11 parameters) for each image on a 5-point scale: 1, very good; 2, good; 3, average; 4, poor; and 5, very poor. RESULTS: For clinical utility in 16 percutaneous endoscopic discectomy cases, mean scores for all 12 parameters were significantly better on the OELD than on the LCD, including organ distinguishability (2.1 vs 3.2, respectively), lesion identification (2.2 vs 3.1), and overall viewing impression (2.1 vs 3.1). For image quality, all 11 parameters were better on the OELD than on LCD. Significant differences were identified in six parameters, including contrast (1.8 vs 2.9), color reproducibility in dark areas (1.8 vs 2.9), and viewing angle (2.2 vs 2.9). CONCLUSION: The high contrast and excellent color reproducibility of the OELD reduced the constraints of imaging under endoscopy, in which securing a field of view may be difficult. Distinguishability of organs was good, including ligaments, dura mater, nerves, and adipose tissue, contributing to good stereoscopic images of the surgical field. These findings suggest the utility of OELD for excellent display of surgical images and for enabling safe and highly accurate endoscopic surgery.

Spino-pelvic-rhythm with forward trunk bending in normal subjects without low back pain.

A strong correlation between low back pain and tight hamstrings has been reported. However, the effect of tight hamstrings on spinal biomechanics remains unclear. The purpose of the study was to investigate spino-pelvic-rhythm during forward bending of the trunk and to clarify the rhythm features with regard to hamstrings tightness. Eighteen healthy male adults with no history of low back pain volunteered to participate. First, we measured the finger-to-floor distance (FFD) in the upright position and set this parameter to 100 %. Using a spinal mouse, spinal alignment was measured in the following four positions: (1) upright posture­100 % FFD; (2) forward bending­50 % FFD; (3) forward bending­25 % FFD; and (4) forward bending­0 % FFD (fingers in contact with the floor). Changes of the angle of the thoracic and lumbar spine as well as the pelvis were calculated. As an indicator of tight hamstrings, we measured straight leg raising (SLR) angle. From positions 1­2 (phase I), the entire spino-pelvic angle moved in 104°. During this phase, the lumbar spine mainly moved. In the second phase (positions 2­3), it moved in 16°. Interestingly, all but 2 subjects showed a negative angle in the thoracic motion, meaning that the thoracic spine extended 4° during trunk flexion, thus exhibiting paradoxical motion. During this phase, lumbopelvic rhythm showed 2 patterns. In 7 subjects, pelvic motion was greater than lumbar motion, while the remaining subjects showed the opposite. In subjects without tight hamstrings, 83 % showed a pelvis-dominant pattern. Only 7 subjects were capable of position 4. During this phase, only slight motion was noted in the spine, and the majority of the motion occurred in the pelvis. Lumbar and pelvic motion correlated negatively in all phases. SLR angle and pelvic motion correlated strongly during phase III, indicating dominant pelvic movement in flexible subjects. The lumbo-pelvic-rhythm comprises 2 patterns­lumbar dominant and pelvis dominant. In flexible subjects, pelvis movement was dominant. In conclusion, improving tight hamstrings may reduce lumbar loading thereby reducing low back pain.

Spino-pelvic-rhythm with forward trunk bending in normal subjects without low back pain.

A strong correlation between low back pain and tight hamstrings has been reported. However, the effect of tight hamstrings on spinal biomechanics remains unclear. The purpose of the study was to investigate spino-pelvic-rhythm during forward bending of the trunk and to clarify the rhythm features with regard to hamstrings tightness. Eighteen healthy male adults with no history of low back pain volunteered to participate. First, we measured the finger-to-floor distance (FFD) in the upright position and set this parameter to 100 %. Using a spinal mouse, spinal alignment was measured in the following four positions: (1) upright posture-100 % FFD; (2) forward bending-50 % FFD; (3) forward bending-25 % FFD; and (4) forward bending-0 % FFD (fingers in contact with the floor). Changes of the angle of the thoracic and lumbar spine as well as the pelvis were calculated. As an indicator of tight hamstrings, we measured straight leg raising (SLR) angle. From positions 1-2 (phase I), the entire spino-pelvic angle moved in 104°. During this phase, the lumbar spine mainly moved. In the second phase (positions 2-3), it moved in 16°. Interestingly, all but 2 subjects showed a negative angle in the thoracic motion, meaning that the thoracic spine extended 4° during trunk flexion, thus exhibiting paradoxical motion. During this phase, lumbopelvic rhythm showed 2 patterns. In 7 subjects, pelvic motion was greater than lumbar motion, while the remaining subjects showed the opposite. In subjects without tight hamstrings, 83 % showed a pelvis-dominant pattern. Only 7 subjects were capable of position 4. During this phase, only slight motion was noted in the spine, and the majority of the motion occurred in the pelvis. Lumbar and pelvic motion correlated negatively in all phases. SLR angle and pelvic motion correlated strongly during phase III, indicating dominant pelvic movement in flexible subjects. The lumbo-pelvic-rhythm comprises 2 patterns-lumbar dominant and pelvis dominant. In flexible subjects, pelvis movement was dominant. In conclusion, improving tight hamstrings may reduce lumbar loading thereby reducing low back pain.

Lumbar spondylolysis in juveniles from the same family: a report of three cases and a review of the literature.

Spondylolysis is reported as a stress fracture of the pars interarticularis with a strong hereditary basis. Three cases of lumbar spondylolysis in juveniles from the same family are reported, and the genetics of the condition are reviewed. The first boy, a 13-year-old soccer player, was diagnosed with terminal stage L5 bilateral spondylolysis with grade 1 slippage. The second boy, a 10-year-old baseball player, had terminal stage right side unilateral spondylolysis. The third boy, also a 10-year-old baseball player, was diagnosed with early stage bilateral L5 spondylolysis. The second and third boys are identical twins, and all three cases exhibited concomitant spina bifida occulta. Lumbar spondylolysis has a strong hereditary basis and is reported to be an autosomal dominant condition.

Percutaneous endoscopic discectomy and thermal annuloplasty for professional athletes.

INTRODUCTION: Percutaneous endoscopic discectomy (PED) for herniated nucleus pulposus has become increasingly popular since first reported by Yeung and Tsou. Additionally, radiofrequency thermal annuloplasty (TA) with PED (PED/TA) has been reported to be effective for discogenic low back pain. We used the PED/TA procedure to successfully treat four professional athletes with discogenic low back pain. METHODS: All patients were men; their age at operation was 35, 35, 34, and 28 years. Daily low back pain was provoked by discography in all four patients, who had been receiving conservative but ineffective treatment for over 1 year. Surgery was conducted with the patients under local anesthesia. A cannula was placed posterior to the disc and ventral to the posterior annulus fibrosus through a 7-mm skin incision. Degenerated nucleus pulposus at the site was removed percutaneously and the posterior annulus was modulated by bipolar radiofrequency TA. RESULTS: After surgery, low back pain was resolved in all cases. After effective post-surgical rehabilitation with a physical trainer or physical therapist, all patients returned to their original competitive level. CONCLUSION: PED/TA is a minimally invasive and effective procedure for discogenic low back pain, especially in athletes.

Four-rod stabilization of severely destabilized lumbar spine caused by metastatic tumor.

We report a case of a 67-year-old female with severely destabilized lumbar spine caused by metastatic malignant tumor. The primary lesion was a thyroid follicular adenocarcinoma. Complete destruction of the L3, L4, and L5 vertebrae had resulted in severe instability, which left the patient with severe back pain and bed-ridden. Since the vertebrae were so severely damaged at 3 levels, 4 rods were used to stabilize the spine. Following stabilization, the pain was alleviated and the patient's quality of life improved. We introduce here the 4-rod technique to stabilize the spine over 3 vertebral levels following severe destruction by metastatic tumor.

V-rod technique for direct repair surgery of pediatric lumbar spondylolysis combined with posterior apophyseal ring fracture.

We report a pediatric baseball player having both a fracture of the posterior ring apophysis and spondylolysis. He was presented to a primary care physician complaining of back pain and leg pain. Despite conservative treatment for 3 months, the pain did not subside. He was referred to our clinic, and surgical intervention was carried out. First, a bony fragment of the caudal L5 apophyseal ring was removed following fenestration at the L5-S interlaminal space, bilaterally: and decompression of the bilateral S1 nerve roots was confirmed. Next, pseudoarthrosis of the L5 pars was refreshed and pedicle screws were inserted bilaterally. A v-shaped rod was inserted beneath the L5 spinous process, which stabilized the pars defects. After the surgery, back pain and leg pain completely disappeared. In conclusion, the v-rod technique is appropriate for the spondylolysis direct repair surgery, especially, in case the loose lamina would have a partial laminotomy.

Percutaneous endoscopic transforaminal approach to decompress the lateral recess in an elderly patient with spinal canal stenosis, herniated nucleus pulposus and pulmonary comorbidities.

A 70-year-old man with severe pulmonary comorbidities was referred to our institution for treatment of a right L5 nerve impingement. He had suffered from spinal canal stenosis and herniated nucleus pulposus (HNP) at the level of L4-L5 for more than a year and had been treated conservatively. However, the pain could not be alleviated, and his primary care physician scheduled posterior decompression surgery. During this procedure, the anesthesiologist refused to induce general anesthesia because of the patient's very poor pulmonary condition. Subsequently, the patient was referred to us. We used a transforaminal approach with percutaneous endoscopic discectomy, with the patient under local anesthesia. First, herniated nucleus pulposus fragments at the disc level were removed. With a trephine drill, the upper part of the L5 pedicle was removed, which allowed for the extraction of dorsally migrated fragments. Following complete removal of the herniated nucleus pulposus fragments, osseous decompression was performed. The osseous endplate of L5 (anterior part of the lateral recess) was removed to enlarge the lateral recess so that decompression of the L5 nerve root was possible. The patient's lower back pain and right leg pain subsided following surgery. Percutaneous endoscopic discectomy is useful for patients with severe comorbidities as it can be done with local anesthesia.

Multilevel direct repair surgery for three-level lumbar spondylolysis.

A 45-year-old man presented to our clinic requesting evaluation for surgical treatment of chronic low back pain of more than 20 years duration. He was diagnosed with 3-level lumbar spondylolysis at L3-5. Direct repair using the pedicle screw and hook-rod system was conducted for all three levels. After the surgery, his low back pain completely disappeared. Six months later, he felt discomfort and heard a metallic sound as he twisted his trunk. Computed tomography and radiography indicated that the hook head for L3 and the screw head for L4 were interfering with each other, causing the sound. We confirmed bony union at L3 and removed the L3 system. Surgeons should be aware of such complications if direct repair using a pedicle screw and hook-rod system is conducted for multilevel spondylolysis.

Jack-knife stretching promotes flexibility of tight hamstrings after 4 weeks: a pilot study.

Tight hamstrings are reported to be one of the causes of low back pain. However, there have been few reports on effective stretching procedures for the tight hamstrings. The so-called jack-knife stretch, an active-static type of stretching, can efficiently increase the flexibility of tight hamstrings. To evaluate hamstring tightness before and after the 4-week stretching protocol in healthy volunteer adults and patients aged under 18 years with low back pain. For understanding the hamstrings tightness, we measured two parameters including (1) finger to floor distance (FFD) and (2) pelvis forward inclination angle (PFIA). Eight healthy adult volunteers who had no lumbar or hip problems participated in this study (mean age: 26.8 years). All lacked flexibility and their FFD were positive before the experiment. Subjects performed 2 sets of the jack-knife stretch every day for 4 weeks. One set consisted of 5 repetitions, each held for 5 s. Before and during the 4-week experiment, the FFD and PFIA of toe-touching tests were measured weekly. For 17 of the sports players aged under 18, only FFD was measured. In adult volunteers, FFD was 14.1 ± 6.1 cm before the experiment and decreased to -8.1 ± 3.7 cm by the end of week 4, indicating a gain in flexibility of 22.2 cm. PFIA was 50.6 ± 8.2 before the experiment and 83.8 ± 5.8 degrees after. Before and after the experiment, the differences were significant (p < 0.05). For those aged under 18, FFD was 8.1 ± 8.0 and -9.6 ± 6.8, before and after the stretching, respectively. This difference was significant (p < 0.05). The jack-knife stretch is a useful active-static stretching technique to efficiently increase flexibility of tight hamstrings.

Endoscope-assisted excision of a juxtafacet cyst in an adolescent athlete: a case report.

BACKGROUND: Juxtafacet cysts (JFCs) are a cause of back and radicular pain that can be treated conservatively and operatively. Such strategies include lumbosacral brace, epidural injection, open surgery, and minimally invasive surgery; although surgical treatment is usually reserved for unsuccessful conservative treatment. The role of minimally invasive surgery in athletic youth with JFCs has yet to be determined. PATIENTS/MATERIAL AND METHODS: The patient is a 16-year-old basketball player with a JFC. We performed endoscope-assisted cystectomy. RESULTS: Endoscope-assisted JFC excision immediately and completely resolved the patient's lower back and leg pain with no recurrence of symptoms 4 years after surgery. CONCLUSION: We suggest that JFCs of the lumbar spine be a part of the differential diagnosis in young patients with back and radicular pain. Furthermore, we recommend that endoscope-assisted surgery be employed in the treatment of JFCs in young athletes.