Posterior spinal fusion in patients with spinal muscular atrophy: a surgical technique to allow intrathecally inject nusinersen.

BACKGROUND: Nusinersen, the recently approved medical therapy in the treatment of spinal muscular atrophy (SMA), has revolutionized the natural history of this disease. Until now, surgical treatment of scoliosis in SMA patients was an exclusion criterion for drug therapy. In fact, the bone graft positioned posteriorly during surgery, in order to obtain a solid fusion, prevented the lumbar puncture necessary for the intrathecal administration of the drug. The aim is to describe a surgical technique that allows for safe and easy intrathecal administration of nusinersen. METHODS: We present a single-center, single-surgeon case series descriptive study. From 2019 to 2021 seven consecutive patients affected by genetically confirmed SMA suitable for treatment with nusinersen and suffered from neuromuscular scoliosis needing posterior spinal fusion surgery were included in the present study. During posterior spinal fusion surgery a L3-L4 or L2-L3 laminectomy was performed to provide safer access to intrathecal injection. The drainage scar was used as a skin landmark so as to facilitate future procedures. RESULTS: The median of operative time was 250 min (range: 200-370 min). The median correction rate was 57% (range: 43.5-68). The median of intraoperative blood loss was 650 mL (range 320-940 mL). The median value of the correction loss at the last follow-up was 10% (range: 4.5-15%). CONCLUSIONS: The surgical procedure allowed all patients to receive nusinersen therapy without complications. The procedure described is simple and effective in providing safe intrathecal access to make these patients suitable for undertaking or continuing the protocol of treatment with nusinersen.

Arthrodesis versus dynamic neutralization: A short/mid- and long-term retrospective evaluation in degenerative disk disease treatment.

Study Design: This was a retrospective comparative study. Objectives: The aim of this study was to perform a clinical and radiological retrospective evaluation of the most used techniques for the lumbar degenerative disk disease (DDD) treatment: arthrodesis versus dynamic neutralization (DN)-Dynesys dynamic stabilization system. Methods: The study included 58 consecutive patients affected by lumbar DDD, 28 treated with rigid stabilization and 30 with DN at our department between 2003 and 2013. The clinical evaluation was performed through the Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI). The radiographic evaluation was performed through standard and dynamic X-ray projections and magnetic resonance imaging. Results: Both techniques determined a clinical improvement in the postoperative period compared to the preoperative one. There were no significant differences between the postoperative VAS of the two techniques. The DN group postoperative ODI percentage showed a significant improvement (P = 0.026) compared to the arthrodesis group. During the follow-up, no clinically significant differences were highlighted between the two techniques. At a long term follow up period, radiographic results showed, in both groups, a L3-L4 disk mean height reduction and an increase of segmental and lumbar lordosis without significant differences between the two techniques. During an average of 96-month follow-up period, 5 (18%) patients developed an adjacent segment disease in the arthrodesis group and 6 (20%) patients developed this syndrome in the DN group. Conclusions: We are confident in recommending arthrodesis and DN as effective techniques for lumbar DDD treatment. Both techniques are potentially burdened, with similar frequency, by the development of long-term adjacent segment disease.

Surgical approach to single-level symptomatic thoracic disc herniations through costotransversectomy: A report of ten case series.

Study Design: This was an observational study. Objectives: The treatment of symptomatic thoracic disc herniation (TDH) remains a matter of debate. We report our experience with ten patients affected by symptomatic TDH, surgically treated through costotransversectomy. Methods: A total of ten patients (four men and six women) with single-level symptomatic TDH were surgically treated by two senior spine surgeons at our institution between 2009 and 2021. The most common type was a soft hernia. TDHs were classified as lateral (5) or paracentral (5). Preoperative clinical symptoms were varied. The diagnosis was confirmed by computed tomography (CT) and magnetic resonance imaging of the thoracic spine. The mean follow-up period was 38 months (range: 12-67 months). The Oswestry Disability Index (ODI), the Frankel grading system, and the modified Japanese Orthopedic Association (mJOA) scoring system were used as outcome scores. Results: Postoperative CT study documented satisfactory decompression either on the nerve root or the spinal cord. All patients experienced a reduction of disability with an improved mean ODI score by 60%. Six patients reported total recovery of neurological function (Frankel Grade E) and four patients improved by 1 Grade (40%). The overall recovery rate estimated with the mJOA score was 43.5%. We reported the absence of significant difference in outcome compared to either calcified and noncalcified discs or paramedian and lateral location. Four patients had minor complications. No revision surgery was required. Conclusion: Costotransversectomy represents a valuable tool for spine surgeons. The major limit of this technique is the possibility to approach the anterior spinal cord.

Case series of four complex spinal deformities: new frontiers in pre-operative planning.

BACKGROUND AND AIM: Osseous and medullar anomalies constitute a hard challenge for interpretation of complex vertebral deformities anatomy. To better frame these deformities three-Dimensional (3D) printing represents a new frontier in this field. The aim of this brief report is describing the use of 3D printed models for surgical planning in four complex vertebral deformity cases treatment. METHODS: Four cases of severe scoliosis were treated between December 2017 and January 2019; patients' mean age was 12,25 years. Two patients underwent neurosurgical intervention for myelomeningocele at the time of birth. Standard and dynamics X-Ray, Computed Tomography (CT) and Magnetic Resonance (MR) of the column were performed pre-operatively. CT files were implemented to build the 3D model of each spine and selected ribs. The models were 3D printed in thermoplastic material, then used to study the deformities and for surgical planning. A survey proposal about 3D models' utility and accuracy has been made to 15 residents and 6 main surgeons. RESULTS: Preparation of each 3D models required about 316.5 minutes and printing time was about 108 hours each. The average cost was 183.16 € to produce one 3D printed model, which resulted useful in surgical planning and educational. CONCLUSIONS: The manufacture of 3D models requires time, resources and multidisciplinary approach, it must be justified by complexity of the case. In this study 3D Printing allowed surgeons to carefully plan and simulate the surgery, ensuring for a better sizing of the implant.

Non-specific spondylodiscitis: a new perspective for surgical treatment.

PURPOSE: Pyogenic spondylodiscitis is a relatively rare spinal disease; non-specific spondylodiscitis (NSS) cases are increasing. This study aims to identify if changes of inflammatory markers under antibiotic therapy can be used to determine which NSS patients can benefit from surgical indication earlier than others. METHODS: Two groups of patients with NSS were examined. Group A underwent surgery, while Group B was treated conservatively. Group B was also subdivided in patients undergoing antibiotic therapy for > 6 weeks (B1) and < 6 weeks (B2). Groups were compared for age, gender, BMI, blood levels of ESR and CRP and VAS scale. RESULTS: There were no differences (P = 0.06) in reduction in ESR at 4 weeks between two main groups. A reduction in CRP, with < 2.7 mg/dl at 4 weeks, was observed in Group A (P = 0.01). Comparing Group B1 to B2, a reduction (P = 0.0001) in VAS, ESR and CRP at 4 weeks was observed in Group B2. It was possible to isolate the pathogen in 52.8% of Group B, without any differences on VAS, ESR and CRP values and on length of the antibiotic therapy. CONCLUSIONS: The surgical treatment should be considered for patients who, after 4 weeks of conservative therapy, do not show a reduction in the ESR < 50 mm/h and of the CRP < 2.7 g/dl. The comparison between groups underwent surgically and those treated conservatively showed a reduction in the CRP at 4 weeks and better VAS for pain at 3 months in Group A.

Percutaneous k-wire leverage reduction and retrograde transphyseal k-wire fixation of angulated radial neck fractures in children.

PURPOSE: To describe clinical and radiographic outcomes after surgical management of angulated radial neck fracture in children. METHODS: Twenty children (aged 2-11 years) with angulated radial neck fracture with more than 30° angulations (Judet type III and IV fractures) were retrospectively reviewed. All the enrolled patients were surgically treated with percutaneous k-wire leverage reduction and retrograde transphyseal k-wire fixation. Clinical outcomes were evaluated using Tibone and Stoltz score and the Mayo Elbow Performance Score (MEPS). Radiographic outcomes were evaluated with Métaizeau score. Complications were also evaluated. RESULTS: At a mean follow-up of 20 months, no patients showed axial deformity of the upper limb or instability of the elbow. The mean value of the MEPS was 99.2, and excellent clinical results were achieved in 14 patients (73.7%) at Tibone and Stoltz score. The final X-rays showed fracture healing in all patients; furthermore, 75% of patients showed excellent reduction at Métaizeau score. No patient developed complication. There were no iatrogenic nerve injuries or pin infections. CONCLUSIONS: The results demonstrate that percutaneous k-wire leverage reduction and retrograde transphyseal k-wire fixation of angulated radial neck fracture treatment is a simple, effective, rapid and inexpensive procedure. LEVEL OF EVIDENCE: IV (case series and systematic review of level IV studies).

A New Single Volar Approach for Both-Bone Fractures of the Forearm: The Mediolateral Windows Approach Extended.

Fractures of the forearm are common injuries in adults. Particularly, both-bone fractures of the radius and ulna are frequently encountered by orthopedic surgeons. To date, these fractures are typically treated with open reduction and internal fixation, because of the propensity for malunion of the radius and ulna and the resulting loss of forearm rotation. We propose a modification of the classic double approach for both-bone fractures of the distal radius and ulna. Indeed, we described a minimal and anatomic approach to prevent complications such as the heterotopic ossification of the interosseus membrane and vascular-nervous lesions. By a single anterior incision, we utilize 2 windows to expose the medial and lateral compartments of the forearm. In this way, we avoid the handling of the interosseous membrane, and we protect the ulnar, median, and radial nerves from the surgical approach. This technique is indicated for complex distal radius and ulna fractures. We exclude open fractures, and Monteggia, Galeazzi, or Essex-Lopresti lesions. In this report, we describe the surgical anatomy, surgical approach, and complications regarding this approach.

Pediatric intervertebral disc calcification: case series and systematic review of the literature.

Pediatric intervertebral disc calcification (PIDC) is an uncommon disease with an unclear etiology. The clinical picture may suggest a severe spinal disease, thus involving an extensive differential diagnosis. The aim of this study was to find a diagnostic and treatment approach for PIDC on the basis of the literature. The Medline, Embase, Web of Science, and Cochrane Systematic Review databases were searched for relevant studies, whose reference lists were checked manually for additional articles. For each study, year of publication, study design, demographics, onset type, history of trauma, clinical and neurological signs and symptoms, imaging studies performed, blood test results, treatment strategies, and outcomes were recorded. The charts of eight patients with symptomatic PIDC treated at our institution from 2000 to 2016 were reviewed. Of 1522 articles identified by the search, 51 level IV studies involving 91 patients fulfilled the inclusion criteria. Most patients were treated conservatively and achieved complete recovery. Of the 13 patients who were treated surgically, one had a persistent myelopathy at the final follow-up. All the patients of our case series were treated conservatively and achieved complete symptom resolution at the final follow-up. PIDC is predominantly a benign and self-limiting condition. Surgery should be considered only in case of failure of conservative treatment in the presence of severe neurological impairment and myelopathy. Level of Evidence: IV (case series and systematic review of level IV studies).

Unilateral uniplanar modular external fixator for percutaneous proximal femoral osteotomy in children: surgical technique.

Varus derotation femoral osteotomy (VDFO) is a commonly used surgical procedure in association with pelvic osteotomy for dislocated hip in developmental hip dysplasia. Several types of internal fixation devices were described in the literature, but none of them showed a superiority or a lower rate of complication over the others. Different types of external fixator were also described for proximal osteotomy fixation with good results. We describe the surgical technique of the VDFO using a modular external fixator with an illustrative case.

Mesenchymal Stem Cells from Nucleus Pulposus and Neural Differentiation Potential: a Continuous Challenge.

Mesenchymal stem cells (MSCs) are well-characterized adult stem cells, recently isolated from human nucleus pulposus of degenerate and non-degenerate intervertebral disc. The attention to this source is linked to its embryologic history and cells may conserve a stronger aptitude to neuronal differentiation than other MSCs. Here, MSCs from nucleus pulposus (NP-MSCs) were successfully isolated and characterized for morphology, proliferation, and expression of selected genes. Subsequently, the neuronal differentiation was induced by 10 days of culture with a neuronal medium. NP-MSCs subjected to neural differentiation media (NP-MSCs-N) showed a morphological and biochemical modifications. NP-MSCs-N displayed elongated shape with protrusion, intermediate filaments, microtubules, and electron dense granules and the ability to form neurospheres. Even if they expressed neural markers such as NESTIN, ß-TUBULIN III, MAP-2, GAP-43, and ENOLASE-2, the neural differentiated cells did not show neither spontaneous nor evoked intracellular calcium variations compared to the undifferentiated cells, suggesting that cells do not have electric functional properties. Further studies are required in order to get a better understanding and characterization of NP-MSCs and analyzed the molecular mechanisms that regulate their neural differentiation potential.

Endoscopic Endonasal Odontoidectomy with Anterior C1 Arch Preservation in Rheumatoid Arthritis: Long-Term Follow-Up and Further Technical Improvement by Anterior Endoscopic C1-C2 Screw Fixation and Fusion.

OBJECTIVE: To examine the long-term outcomes (minimum of 4.5 years) of endoscopic endonasal odontoidectomy (EEO) with preservation of anterior C1 ring to treat irreducible ventral bulbo-medullary compressions in rheumatoid arthritis (RA) and to illustrate a novel technique of anterior pure endoscopic craniovertebral junction (CVJ) reconstruction and fusion. In fact, long-term clinical studies are still lacking to elucidate the effective role of EEO and whether it can obviate the need for posterior fixation. METHODS: From November 2008 to January 2012, clinical and radiologic data of 7 patients presenting with RA and associated irreducible bulbo-medullary compression treated with EEO were analyzed retrospectively. In all patients, decompression was achieved by EEO with anterior C1 arch preservation. In the last 2 patients, after EEO, we used the spared anterior C1 arch for reconstruction of anterior column of CVJ by positioning, under pure endoscopic guidance, autologous bone and 2 tricortical screws between the anterior arch of C1 and the residual odontoid. All patients were examined clinically with Ranawat classification and radiographically with computed tomography, magnetic resonance imaging, and dynamic radiography immediately after surgery and during follow-up. RESULTS: Adequate bulbo-medullary decompression with anterior C1 arch preservation was obtained in all cases. At follow-up (average, 66.2 months; range, 51-91 months) all patients experienced an improvement at least of one Ranawat classification level and presented no clinical or radiologic signs of instability. CONCLUSIONS: EEO with anterior C1 arch sparing provides satisfying long-term results for irreducible ventral CVJ lesions in RA. The preservation of anterior C1 arch and, when possible, the reconstruction of anterior CVJ can prevent the need for posterior fusion.

OP-1 Compared with Iliac Crest Autograft in Instrumented Posterolateral Fusion: A Randomized, Multicenter Non-Inferiority Trial.

BACKGROUND: Spinal fusion with the use of autograft is a commonly performed procedure. However, harvesting of bone from the iliac crest is associated with complications. Bone morphogenetic proteins (BMPs) are extensively used as alternatives, often without sufficient evidence of safety and efficacy. The purpose of this study was to investigate non-inferiority of osteogenic protein-1 (OP-1, also known as BMP-7) in comparison with iliac crest bone graft in posterolateral fusions. METHODS: This study was a randomized, controlled multicenter trial. Patients who underwent a single-level instrumented posterolateral fusion of the lumbar spine for degenerative or isthmic spondylolisthesis with symptoms of neurological compression were randomized to receive OP-1 combined with local bone (OP-1 group) or autologous bone graft from the iliac crest combined with local bone (autograft group). The primary outcome was overall success, defined as a combination of clinical success and evidence of fusion on computed tomography (CT) scans, at one year postoperatively. RESULTS: One hundred and nineteen patients were included in the study, and analysis of the overall outcome was performed for 113. Non-inferiority of OP-1 compared with iliac crest autograft was not found at one year, with a success rate of 40% in the OP-1 group versus 54% in the autograft group (risk difference = -13.3%, 90% confidence interval [CI] = -28.6% to +2.10%). This was due to the lower rate of fusion (the primary aim of OP-1 application) seen on the CT scans in the OP-1 group (54% versus 74% in the autograft group, p = 0.03). There were no adverse events that could be directly related to the use of OP-1. CONCLUSIONS: OP-1 with a collagen carrier was not as effective as autologous iliac crest bone for achieving fusion and cannot be recommended in instrumented posterolateral lumbar fusion procedures. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Endoscopic Transnasal Odontoidectomy With Anterior C1 Arch Preservation and Anterior Vertebral Column Reconstruction in Patients With Irreducible Bulbomedullary Compression by Complex Craniovertebral Junction Abnormalities: Operative Nuance.

BACKGROUND: During the past decades, the transoral transpharyngeal approach has been advocated as the standard route for the removal of odontoid causing an irreducible symptomatic neural compression. However, it may be potentially associated with a significant built-in morbidity because of the splitting of the soft palate for an adequate working angle, tracheostomy, and incision of the oral mucosa, causing exposure to a higher risk of infection by oral flora. OBJECTIVE: To describe our experience with the minimally invasive pure endoscopic transnasal odontoidectomy in patients with bulbomedullary compression affected by complex anterior craniovertebral junction abnormalities. METHODS: Five patients underwent a pure endoscopic neuronavigation-assisted transnasal odontoidectomy with anterior C1 arch preservation. Moreover, the anterior cervical spine column was reconstructed by filling the gap between the C1 arch and the residual C2 body with autologous/artificial bone. Neither tracheostomy nor enteral tube feeding were needed in any case. RESULTS: A postoperative neurological improvement was observed in all patients. Postoperative imaging confirmed a satisfactory spinal cord decompression with cervical anterior column arthrodesis, and without evidence of instability at follow-up, so far. CONCLUSION: The endoscopic transnasal approach seems to represent an efficient and safe alternative to the transoral route for the resection of odontoid process causing irreducible bulbomedullary compression. It provides a straightforward and minimally invasive natural surgical corridor to the anterior craniocervical junction, allowing a better working angle with preservation of spine biomechanics, while minimizing potential comorbidities.

Is posterior fixation alone effective to prevent the late kyphosis after T-L fracture?

INTRODUCTION: The posterior transpedicular fixation technique is a standard procedure for stabilizing the injured thoracolumbar spine but the long-term results of this approach are controversial. Clear guidelines are missing and the literature shows complete disagreement regarding indications, approaches, surgical techniques, and type of fixation. MATERIAL AND METHOD: The objective of this study is to investigate if the surgical treatment by posterior approach alone is always enough to prevent the late kyphotic deformity through the retrospective analysis of 219 patients affected with a thoracolumbar injury. Follow-up examinations included radiographic measurements of the sagittal index (SI) and the sagittal plane kyphosis (SPK). RESULT: Results show that, at the follow-up, the SI remains almost stable after the surgical correction, while the SPK (which describes the eventual injury of the affected intervertebral disc) decreases indicating a progressive regional kyphotic deformity. Thus, in some cases posterior fixation alone is not sufficient for long-term spinal stabilization and often can be not effective to prevent the late kyphotic deformity.

Endoscopic endonasal odontoidectomy with anterior C1 arch preservation in elderly patients affected by rheumatoid arthritis.

BACKGROUND CONTEXT: Rheumatoid arthritis is the most common inflammatory disease involving the spine with predilection for the craniovertebral segment. Surgery is usually reserved to patients with symptomatic craniovertebral junction (CVJ) instability, basilar invagination, or upper spinal cord compression by rheumatoid pannus. Anterior approaches are indicated in cases of irreducible ventral bulbo-medullary compression. Classically performed through the transoral approach, the exposure of this region can be now achieved by a minimally invasive endonasal endoscopic approach (EEA). PURPOSE: The aim of this article is to demonstrate the feasibility of performing an odontoidectomy and a rheumatoid pannus removal by a minimally invasive EEA, preserving the anterior C1 arch continuity and avoiding a posterior fixation procedure. STUDY DESIGN: Technical description and cohort report. METHODS: We report three cases of elderly patients with a long history of rheumatoid arthritis and irreducible anterior bulbo-medullary compression secondary to basilar invagination and/or rheumatoid pannus. Anterior decompression was achieved by an endonasal image-guided fully endoscopic approach. RESULTS: Neurological improvement and adequate bulbo-medullary decompression were obtained in all cases. The anterior C1 arch continuity was preserved, and none of the patients required a subsequent posterior fixation. CONCLUSIONS: Anterior decompression by a minimally invasive EEA could represent an innovative option for the treatment of irreducible ventral CVJ lesions in elderly patients with rheumatoid arthritis. This approach permits the preservation of the anterior C1 arch and the avoidance of a posterior fixation, thus preserving the rotational movement at C0-C2 segment and reducing the risk of a subaxial instability development.

Endoscopic transnasal odontoid resection to decompress the bulbo-medullary junction: a reliable anterior minimally invasive technique without posterior fusion.

PURPOSE: Anterior decompression of the craniovertebral junction is reserved to patients with irreducible ventral bulbo-medullary lesions and rapidly deteriorating neurological functions. Classically performed through the transoral approach, the exposure of this region can be now achieved by a minimally invasive endonasal endoscopic approach (EEA). METHODS: Four patients with irreducible, anterior bulbo-medullary compression due to rheumatoid pannus and basilar invagination were enrolled. The imaged-guided EEA was used to resect the odontoid process, trying to preserve the C1 anterior arch. RESULTS: Neurological improvement and adequate bulbo-medullary decompression were obtained in all patients. In two cases, anterior C1 ring was preserved. These patients did not required a posterior fusion. CONCLUSIONS: Compared with the standard transoral technique, the EEA provides the same good exposure but with potentially less complications. The preservation of the anterior C1 arch can contribute to avoid cranial settling and posterior fusion with its related risk of subaxial instability.

"In situ" fusion or reduction in high-grade high dysplastic developmental spondylolisthesis (HDSS).

PURPOSE: To assess if the evaluation of the spino-pelvic balance can be effective in the surgical decision making of the high-grade high dysplastic developmental spondylolisthesis (HDDS). METHODS: Sixteen patients affected with high-grade HDDS (6 treated with "in situ" fusion, and 10 with reduction and fusion) were retrospectively evaluated. A clinical and radiological assessment of the deformity correction was carried out, with a minimum follow-up of 2 years. The differences between the pre- and postoperative measures were statistically analyzed using a two-tailed, paired t test. RESULTS: The six patients treated with "in situ" fusion showed no statistically significant change at the last follow-up relative to pelvic tilt (PT), sacral slope (SS), and grade, while the 10 patients treated with reduction showed significant changes: PT significantly decreased following surgery, while SS and grade significantly increased. CONCLUSIONS: The analysis of the spino-pelvic sagittal balance allows to identify two types of HDDS: the balanced deformities, which do not need reduction, and the unbalanced deformities, in which correction is needed.

Novel concepts in the evaluation and treatment of high-dysplastic spondylolisthesis.

The classification system of spondylolisthesis proposed by Marchetti and Bartolozzi is the most practical regarding prognosis and treatment and includes the description of both low- and high-dysplastic developmental spondylolisthesis (HDDS). Unfortunately, it does not provide strict criteria on how to differentiate between these two subtypes. The accepted treatment for HDDS is surgical. However, there is no consensus on how to surgically stabilize this subtype of spondylolisthesis, and although the concept of reducing spinal deformity before fusion is attractive, the issue of surgical reduction versus in situ fusion remains controversial, especially for HDDS (Meyerding Grades III and IV). The purpose of this study was (1) to describe the severity index (SI) as a simple method that can be used in the identification of low-dysplastic developmental spondylolisthesis from HDDS allowing earlier surgical stabilization to prevent slip progression, (2) to provide guidelines for using the unstable zone for the inclusion of L4 in stabilization, and (3) to describe a surgical technique in the reduction and stabilization of this challenging surgical entity in an attempt to decrease the risk of iatrogenic L5 neurologic injury. The concepts of SI and unstable zone in the evaluation and treatment of HDDS are relatively new. In our study, patients with an SI value >20% were classified as having HDDS and surgical stabilization was offered. In addition, all vertebrae that were contained in the defined unstable zone were surgically instrumented and fused with attempts at anatomic reduction. This case series involved the retrospective radiological review of 25 consecutive patients surgically treated for HDDS between April 2000 and September 2004 by two senior surgeons. All 25 patients had a minimum 3-year follow-up. Reduction of slip, lumbosacral kyphosis, sacral inclination, fusion rate, maintenance of reduction, and iatrogenic L5 neurologic injury were evaluated. Twenty-two patients underwent a single-level L5-S1 fusion. Three patients had extension of the L5-S1 fusion to include L4 because it fell into the unstable zone. Slip improved from 67.2 to 13.6%, focal L5-S1 kyphosis improved from +17.5 degrees to -6.4 degrees . There were no pseudoarthroses and all patients had radiographic evidence of solid bony fusion at latest follow-up. To date, there have been no re-operations secondary to progression of deformity or loss of fixation. Two re-operations were performed, one for a superficial wound infection, the other for further laparoscopic decompression for continued L5 nerve root symptoms after the index surgery. One patient developed an iatrogenic L5 radiculopathy with dysaesthesiae 3 days postoperatively which completely resolved over 6 weeks. HDDS is best treated surgically. Early identification and stabilization of this challenging surgical entity could prevent the progression of slip and deformity making the index surgery less technically demanding. Vertebrae that are contained in the unstable zone can be instrumented and stabilized so that progression of the deformity and re-operation might be avoided. The authors suggested surgical technique can provide a way to restore sagittal balance, provide an environment for successful fusion, and decrease the risk of iatrogenic L5 neurologic injury.

Responsiveness of Dupuytren's disease fibroblasts to 5 alpha-dihydrotestosterone.

PURPOSE: We recently showed that androgen receptors are expressed in Dupuytren's contracture. The aim of the present work was to test the responsiveness of Dupuytren's fibroblasts to 5 alpha-dihydrotestosterone (5 alpha-DHT), the active form of testosterone. RESULTS: Cultured palmar fascia cells from 10 patients with Dupuytren's contracture and 4 normal subjects were exposed to 5 alpha-DHT (10 or 100 ng/mL) for 1, 3, 7, and 15 days. Their phenotype was analyzed immunohistochemically for alpha-smooth muscle actin and androgen receptor expression and proliferation rates were studied. RESULTS: At 15 days the higher concentration of 5 alpha-DHT induced an increase in Dupuytren's fibroblast proliferation, whereas anti-alpha-smooth muscle actin exhibited the strongest expression. At the same time point androgen receptor expression decreased with the lower concentration and disappeared altogether with the higher dose of 5 alpha-DHT. CONCLUSIONS: The palmar fascia is a target tissue for androgen action via androgen receptors. Further studies are required to determine whether control of androgen receptor may control the evolution of Dupuytren's disease.

Cytokines and growth factors in the protruded intervertebral disc of the lumbar spine.

Nerve root irritation induced by factors produced by the intervertebral disc may play a crucial role in the pathophysiology of sciatic pain production. In this study we used immunohistochemistry to investigate the presence of transforming growth factor-beta1 (TGF-beta1), insulin-like growth factor-1 (IGF-1), interleukin-6 (IL-6), IL-6-receptor (IL-6R) and fibronectin in lumbar disc bioptic specimens from 30 patients with disc herniation (protrusion type). Chondrocytes of herniated discs stained positive for TGF-beta1, IGF-1, IL-6 and fibronectin. We demonstrated for the first time the presence of IL-6-R in the chondrocytes of herniated tissue. Specimens from autoptic healthy tissue were used as controls. In these sections no immunoreaction for TGF-beta1, IL-6, or IL-6R was found, while they expressed IGF-1 and fibronectin, but in lower quantities than herniated discs. These results demonstrated the production of factors such as TGF-beta1, IGF-1, IL-6, IL-6R and fibronectin at the site of lumbar disc herniation.