Characterising the arthroplasty in spondyloarthropathy in a large cohort of eighty-seven patients with alkaptonuria.

Arthroplasty in the spondyloarthropathy (SPOND) of alkaptonuria (AKU) in incompletely characterised. The aim was to improve the understanding of arthroplasty in AKU through a study of patients attending the National Alkaptonuria Centre (NAC). Eighty-seven patients attended the NAC between 2007 and 2020. Seven only attended once. Fifty-seven attended more than once and received nitisinone 2 mg daily. Twenty-three attended at least twice without receiving nitisinone. Assessments including questionnaire analysis eliciting details of arthroplasty and other surgical treatments for SPOND, 18 FPETCT and CT densitometry at the neck of hip and lumbar spine, as well as photographs of the eyes and ears were acquired from patients attending the National Alkaptonuria Centre (NAC) at baseline when 2 mg nitisinone was commenced, and yearly thereafter. Photographs were scored to derive ochronosis scores. Blood and urine samples were collected for chemical analyses. The prevalence of arthroplasty was 36.8%, similar in males and females, occurring especially in the knees, hips and shoulders. Multiple arthroplasties were found in 29 patients (33.3%) in this cohort. Incident arthroplasty was 6.5% in the nitisinone group and 7.1% in the no-nitisinone group. Incident arthroplasty was 11.3% in the group with baseline arthroplasty and 3.51% in the group without. A strong association of arthroplasty with SPOND (R = 0.5; P << .0001) and ochronosis (R = 0.54; P < .0001) was seen. Nitisinone had no significant effect on incident arthroplasty. Arthroplasty due to ochronosis and SPOND is common in AKU. Nitisinone decreased ochronosis but had no effect on arthroplasty in this cohort.

Management of a pseudarthrosis with sagittal malalignment in a patient with ochronotic spondyloarthropathy.

PURPOSE: Ochronotic spondyloarthropathy is an uncommon disease, and its association to sagittal malalignment in the context of a pseudarthrosis has never been described. METHODS: We present the case of a 56-year-old female, who underwent previously L4L5 laminectomy for central canal stenosis and started later on to complain of progressively severe low back pain with a significant forward imbalance while walking. X-rays showed non-compensated sagittal malalignment due to thoracolumbar kyphosis, CT scan revealed multilevel central intradiscal calcifications with important vacuum disc at L4L5, and MRI showed T1 and T2 hypointensity signal at the same level with bone marrow oedema. Alkaptonuric ochronosis was suspected and confirmed by the presence of homogentisic acid in the urine, and the diagnosis of L4L5 pseudarthrosis with associated severe sagittal malalignment in the context of ochronotic spondyloarthropathy was established. RESULTS: The patient underwent surgery with a posterior-only approach with a long-segment pedicle screw construct from T10 to the pelvis with a 360° fusion with a cage at L4L5. Samples taken from the disc and ligaments confirmed the diagnosis of ochronotic spondyloarthropathy macroscopically and microscopically. She could walk on day 2 with a satisfactory clinical and radiological result at 2 years. CONCLUSION: This is the first case in the literature to describe a post-laminectomy pseudarthrosis leading to a significant sagittal malalignment in a patient with ochronotic spondyloarthropathy. Management of such a case is challenging as the spine is partially ankylosed; therefore, a long construct is advisable to avoid ankylosing disorders related complications.

Clinical outcomes after posterior cervical decompression and fusion surgery for destructive spondyloarthropathy in patients undergoing long-term hemodialysis: A matched case-control study.

BACKGROUND: Cervical destructive spondyloarthropathy (DSA) often leads to cervical myelopathy in long-term hemodialysis patients. However, the surgical outcomes after instrumented fusion surgery for cervical DSA are still unclear. The objective of this study was to investigate the clinical outcomes of cervical DSA in comparison with a control group. MATERIALS AND METHODS: A consecutive series of 20 undergoing long-term hemodialysis patients who underwent instrumented fusion surgery for cervical DSA between 2010 and 2016 were included in this study (DSA group). The mean age at surgery was 65 years, and there were 11 men and 9 women. The average length of hemodialysis was 23 years. The age- and sex-matched control group consisted of 20 patients (degenerative conditions). The Japanese Orthopedic Association (JOA) score, recovery rate, complications, and loss of correction of fused level were compared between the groups. RESULTS: Two of the 20 patients died due to perioperative complications. More than 1 year of follow-up data after surgery was available for 18 patients. The mean JOA score significantly increased from 5.4 before surgery to 9.7 at 1 year after surgery and 8.3 at the final follow-up (mean: 33.2 ± 21.3 months, P = 0.019). There were no significant differences in the mean recovery rate (41% vs. 37%, P = 0.44) between the DSA group and control group. Loss of correction of more than 5°was significantly higher in the DSA group (44% vs. 10%, P = 0.027). The rate of pseudarthrosis (17% vs. 5%, P = 0.328) and adjacent segment disease (22% vs. 10%, P = 0.17) tended to be higher in the DSA group. DISCUSSION: The clinical outcomes showed significant recovery in both groups. Therefore, posterior cervical decompression and fusion surgery was effective for treating cervical DSA.

Quadriplegia caused by an epidural abscess occurring at the same level of cervical destructive spondyloarthropathy: a case report.

BACKGROUND: Destructive spondyloarthropathy (DSA) is one of the major complications in patients undergoing long-term hemodialysis. To the best of our knowledge, an epidural abscess occurring at the level of preexisting cervical DSA has not been well described in the literature. We report a unique case of quadriplegia caused by an epidural abscess occurring at the same level of preexisting cervical DSA. CASE PRESENTATION: A 49-year-old woman was transferred to our emergency department with 5 days of sepsis, drowsy mental status, and quadriplegia below the C5 level. The patient had a medical history of hemodialysis for 10 years. Magnetic resonance imaging showed spinal cord compression by an epidural abscess at the level of preexisting cervical DSA. Blood culture revealed methicillin-sensitive Staphylococcus aureus. Infection of the arteriovenous (AV) shunt was considered as the primary focus of sepsis and pyogenic spondylitis. We performed an emergent open door laminoplasty and the vascular team debrided the infected AV shunt site. Approximately 8 months after surgery, the patient was able to perform activities of daily living somewhat independently. CONCLUSIONS: Emergent surgical decompression and intensive medical care led to successful recovery from a septic and quadriplegic state in this patient. When diagnosing a patient who has undergone long-term hemodialysis presenting with neurologic deficits, the possibility of infectious spondylitis at the same level as DSA should be considered.

Prognosis and adjacent segment disease after lumbar spinal fusion surgery for destructive spondyloarthropathy in long-term hemodialysis patients.

BACKGROUND: Lumbar destructive spondyloarthropathy (DSA) is a serious complication in long-term hemodialysis patients. There have not been many reports regarding the surgical management for lumbar DSA. In addition, the adjacent segment pathology after lumbar fusion surgery for DSA is unclear. The objective of this study was to assess the clinical outcome and occurrence of adjacent segmental disease (ASD) after lumbar instrumented fusion surgery for DSA in long-term hemodialysis patients. MATERIALS AND METHODS: A consecutive series of 36 long-term hemodialysis patients who underwent lumbar instrumented fusion surgery for DSA were included in this study. The mean age at surgery was 65 years. The mean follow-up period was 4 years. Symptomatic ASD was defined as symptomatic spinal stenosis or back pain with radiographic ASD. The Japanese Orthopedic Association score (JOA score), recovery rate (Hirabayashi method), complications, and reoperation were reviewed. RESULTS: The mean JOA score significantly increased from 13.5 before surgery to 21.3 at the final follow-up. The mean recovery rate was 51.4%. Six of the 36 patients died within 1 year after index surgery. One patient died due to perioperative complication. Symptomatic ASD occurred in 43% (13 of 30) of the cases. Of these 13 cases, 5 had adjacent segment disc degeneration and 8 had adjacent segment spinal stenosis. Three cases (10%) required reoperation due to proximal ASD. Multi-level fusion surgery increased the risk of ASD compared with single-level fusion surgery (59% vs. 23%). The recovery rate was significantly lower in the ASD group than the non-ASD group (38% vs. 61%). DISCUSSION: This study demonstrated that symptomatic ASD occurred in 43% of patients after surgery for lumbar DSA. A high mortality rate and complication rate were observed in long-term hemodialysis patients. Therefore, care should be taken for preoperative planning for surgical management of DSA.

Insights and preventive approaches of rod erosion in the occipital bone after complex posterior cervical spine surgery for destructive spondyloarthropathy: A case report.

RATIONALE: Complications of rod migration into the occipital bone after upper cervical fusion are very rare. No other cases have been reported, especially when associated with destructive spondyloarthropathy (DSA). The purpose of this case report is to remind clinicians of the risk of rod migration in cervical spine surgery in patients with DSA and to provide information on its causes, countermeasures, and treatment. PATIENT CONCERN: This case report presents the clinical course of a 61-year-old female patient with chronic kidney disease that required hemodialysis. DIAGNOSIS, INTERVENTION, OUTCOMES: The patient was diagnosed DSA involving the cervical spine. Initial treatment involved a halo vest, followed by anterior cervical corpectomy and fusion spanning from C5 to Th1. However, subsequent complications, including C5 fractures, kyphotic cervical alignment, and rod migration into the occipital bone, lead to multistage surgical interventions. This case highlights the challenges in managing DSA, the significance of optimal fixation strategies, and the importance of accounting for potential alignment changes. CONCLUSION: The effective management of occipital bone erosion after posterior cervical spine surgery for destructive spondyloarthropathy necessitates meticulous fixation planning, proactive rod length adjustment, preoperative assessment of the occipital position, and consideration of the compensatory upper cervical range of motion to prevent migration-related issues.

Clinical outcomes of spinal surgery in patients treated with hemodialysis.

STUDY DESIGN: Retrospective study. OBJECTIVE: The purpose of this study is to review clinical outcomes, including survival rate, and to discuss the potential benefit of surgical treatments for spinal disorders in patients treated with long-term hemodialysis (HD). SUMMARY OF BACKGROUND DATA: Long-term HD is known to possibly cause destructive spondyloarthropathy (DSA) with spinal canal stenosis. There have been few reports, however, regarding clinical outcomes and patient survival rates after spinal surgeries in this population. METHODS: We retrospectively reviewed 33 chronic HD patients who underwent 21 cervical and 13 lumbar spinal surgeries. According to the radiologic findings, we divided them into the non-DSA and the DSA groups. In general, only decompression was performed for the non-DSA patients, whereas spinal fusion was added for the DSA patients. We analyzed the following data, respectively: male-female ratio, age, operative time, estimated blood loss, duration of HD, follow-up duration, preoperative and postoperative Japanese Orthopaedic Association score, improvement ratio of the Japanese Orthopaedic Association score, amyloid deposition characteristics, and survival rate. RESULTS: All patients improved neurologically and functionally after surgery. There were significant differences in the operative time between the DSA and the non-DSA groups in patients with cervical spinal lesions, whereas in patients with lumbar spinal lesions, there were significant differences in sex, operative time, and estimated blood loss. Amyloid deposition was found signficantly more commonly in DSA than in non-DSA patients and was associated with a longer duration of HD. Nine patients died within 49 months of the surgery because of HD-related complications, but there was no surgery-related morbidity. Kaplan-Meier analysis showed a trend toward decreased survival rate in non-DSA patients more than 40 months after the index surgery. CONCLUSIONS: Even in patients treated with long-term HD, spinal surgeries reliably obtain neurological and functional improvement if surgeons judge the preoperative inclusion criteria correctly. However, if surgeries are necessary for these patients, surgeons should consider the patients' comorbidity-related survival rate after the spinal surgeries.

Evaluation of pain as a preference-based health status measure in patients with cervical spondylotic myelopathy undergoing central corpectomy.

BACKGROUND: Assessment of pain in patients with cervical spondylotic myelopathy (CSM) before and after decompressive surgery has not been adequately addressed in the literature. The purpose of this study was to ascertain the intensity of various pain scores in patients with cervical spondylotic myelopathy (CSM) before and after surgery, and to assess their correlation with other outcome measures. METHODS: In this prospective study, 51 patients with CSM were assessed preoperatively and 1 year or more after uninstrumented central corpectomy (CC) using the Visual Analogue Scale (VAS), Nurick grade, patient perceived outcome score (PPOS) and SF-36. RESULTS: At presentation, there was a higher incidence of neck pain (43.1%) and arm pain (51%) than low axial pain (23.5%), with the mean VAS scores being 53.6 ± 27.4, 55.5 ± 27.4 and 34.0 ± 20.3, respectively. Following surgery, the mean neck, arm and low axial pain scores decreased significantly (p < 0.05) to 14.4 ± 22.6, 5.2 ± 11.8 and 16.0 ± 26.1, respectively. Improvement in pain scores demonstrated poor agreement (κ <0.2) with PPOS, Nurick grade recovery rate (NGRR), and the physical component summary (PCS) and mental component summary (MCS) of the SF-36. Pain scores did not influence quality of life as assessed by SF-36. CONCLUSIONS: Pain was reported by about half the patients with CSM, but was not severe in any of them. Following decompressive surgery, the intensity of all these pain components decreased significantly. Low axial pain, a reflection of CSM-related spasticity perceived in the lumbosacral region, became prominent in many patients after surgery.

Characteristics of dialysis-related amyloidosis in patients on haemodialysis therapy for more than 30 years.

BACKGROUND: Dialysis-related amyloidosis is one of the chronic the complications of haemodialysis. We conducted an investigation of dialysis-associated amyloidosis in extremely long-term survivors. METHODS: Twenty-one patients on haemodialysis for more than 30 years ('30+' group) and 13 patients on haemodialysis for 20-30 years ('20-30' group) at Sangenjaya Hospital were enrolled in this study. The frequencies of operations for conditions related to haemodialysis-related amyloidosis were examined. RESULTS: The mean age at the start of haemodialysis was younger in the '30+' group (29.1 +/- 7.3 years) than in the '20-30' group (40.5 +/- 8.2 years, P = 0.0003). Eighteen (85.7%) patients had undergone surgery for CTS, six (28.6%) had undergone surgery for trigger finger and six (28.6%) had undergone surgery for cervical destructive spondyloarthropathy (DSA) at 30 years after the start of haemodialysis therapy. Patients who were over the age of 30 years at the start of dialysis therapy more frequently underwent CTS operations (100%) than those who were under 30 years of age at the start of dialysis (76.9%; P = 0.025) in the '30+' group at 30 years after the start of haemodialysis. The frequencies of operations for CTS did not differ significantly between the '20-30' group and the '30+' group. CONCLUSIONS: Haemodialysis-associated amyloidosis was common in extremely long-term survivors. Even though the mean age at the start of haemodialysis was younger in the '30+' group than in the '20-30' group, the frequency of operations for CTS did not differ. This may be attributable to the recent advances in haemodialysis technologies.

Surgical management of a complex case of Charcot arthropathy of the spine: a case report.

Introduction: The authors present a case of a 55-year-old male with T10 complete paraplegia diagnosed with Charcot arthropathy of the spine (CAS). Case presentation: He presented to an outside institution with vomiting and productive cough with subsequent computed tomography (CT) and MRI imaging revealing L5 osteomyelitis and a paraspinal abscess. Given the patient's inability to remain in good posture in his wheelchair he underwent a multilevel vertebrectomy and thoracolumbar fusion. Due to multiple co-morbidities, surgical recovery was complex, ultimately requiring revision circumferential fixation. Discussion: CAS is an uncommon, long-term complication of traumatic spinal cord injury (SCI). Surgical management is often complex and associated with significant complications. Currently, a consensus on CAS prevention, specific surgical fixation techniques and post-surgical nursing care management is lacking. In this case report we provide our experience in the management of a complex case of CAS to aid in decision making for future neurosurgeons who encounter this sequela of traumatic SCI.

Quantitative Correction of Cervical Sagittal Deformity in Atlanto-Axial Dislocation.

STUDY DESIGN: A mechanism-based reasoning and retrospective cohort study. OBJECTIVE: To establish a quantitative relationship between the change of clivo-axial angle (CXA) and the change of subaxial cervical lordosis (CL) in correction surgery of atlantoaxial dislocation (AAD). SUMMARY OF BACKGROUND DATA: The evolving understanding of mechanism has dramatically improved the treatment modality of AAD. Cervical sagittal alignment is another important aspect of the surgery, in addition to reduction of odontoid process. However, a quantitative reference for correction surgery has not been established. METHODS: Frankfort-axial angle (FXA) was introduced. Based on two assumptions, (1) sagittal alignment of the spine aims at keeping horizontal gaze and (2) deformities at craniovertebral junction make little impact on slope of T1 vertebra, we deduced that the change of CXA equaled change of CL (ΔCXA = -ΔCL). We retrospectively reviewed our case cohort to validate this finding with linear regression analysis. RESULTS: Sixteen cases (eight male and eight female, mean age 40.4±12.5 yr old) were included. Liner fitting equation for ΔFXA and ΔCXA is y=1.005x (coefficient of determination, R=0.966; significance of the estimated coefficients P<0.001, t-statistics) and that for ΔCL and ΔCXA is y=-1.023x (R=0.976, P<0.001). These results support our deduction that ΔCXA = -ΔCL, which can be used as a guidance of quantitative correction of sagittal deformity in AAD. CONCLUSION: Correction of CXA will influence the subaxial cervical lordosis (ΔCXA = -ΔCL) of AAD patients. This equation can serve as a quantitative reference for preoperative planning and intraoperative refining of the correction of cervical sagittal deformity in AAD. LEVEL OF EVIDENCE: 4.

Surgical treatment of the severely damaged atlantoaxial joint with C1-C2 facet spacers: Three case reports.

RATIONALE: Atlantoaxial subluxation (AAS), caused by congenital factors, inflammation such as rheumatoid arthritis, infection, neoplasia, or trauma, is rare and severely erodes and subluxates atlantoaxial (AA) joints. For these patients, surgical reduction, and stabilization are difficult. Surgery, including anterior transoral decompression and posterior fixation, anterior endonasal decompression and fixation, and posterior decompression with AA or occipitocervical fixation, is often the only treatment available. However, there have only been 2 reports of C1-C2 facet spacer use in treating AAS. Here, we report the case histories of 3 patients with severely damaged and subluxated AA joints and symptomatic basilar invagination (BI), malalignment, or C2 root compression. PATIENT CONCERNS: The cases included 2 women with rheumatoid arthritis and 1 man with spondyloarthropathy secondary to ulcerative colitis. DIAGNOSIS: Radiographic imaging revealed severely damaged and subluxated AA joints. Their symptoms included worsening pain in the neck or occiput with or without myelopathy and neuralgia. INTERVENTIONS: After realignment with C1-C2 spacers and posterior C1-C2 screw fixation, the patient symptoms were resolved. OUTCOMES: Of note, 2 of the 3 patients were healed without complications. One patient who underwent secondary revision surgery because of rod breakage and obvious nonunion at C0-C2 was determined to be healed at 1-year follow-up after the revision surgery. LESSONS: We confirmed that C1-C2 facet spacers both reduced BI and occipitocervical coronal malalignment as well as releasing C2 root compression. Therefore, surgical restoration and fixation should be a required treatment in this very rare group of patients.

"As Black as Ink": A Case of Alkaptonuria-Associated Myelopathy and a Review of the Literature.

STUDY DESIGN: Case report and literature review. OBJECTIVE: To characterize the rare presentation of myelopathy occurring secondary to alkaptonuria and to evaluate the available evidence regarding its treatment. SUMMARY OF BACKGROUND DATA: Alkaptonuria is an autosomal recessive genetic condition with an estimated incidence of 1 in 250,000 to 1 in 1,000,000 people. Mutation of the enzyme homogentisate 1,2-dioxygenase leads to the production of high levels of homogentisic acid, with subsequent deposition in ligaments, cartilage, and menisci. Involvement of the spine is termed "ochronotic spondyloarthropathy," of which myelopathy is an uncommon presentation. METHODS: We present the case of a 57-year-old man with alkaptonuria-associated myelopathy, who underwent surgical decompression. Ten additional cases were identified in the literature by a systematic search of PubMed and Google Scholar. RESULTS: In a patient presenting with myelopathy, alkaptonuria may be suspected because of medical history, family history, symptoms (including darkened urine, pigmented ear cartilage, and sclera), or radiographic changes, such as multilevel disc collapse, progressive wafer-like disc calcification, extensive osteophyte formation, and spinal deformity. The diagnosis can be confirmed by urine homogentisic acid testing. Of the 11 patients presented here or identified in the literature, 2 were treated nonoperatively, 8 were treated with decompressive spinal surgery, and treatment of the myelopathy was not discussed for 1 patient. In all cases in which outcomes were reported, substantial improvement in the patient's condition was seen. CONCLUSION: Alkaptonuria is a rare cause of myelopathy, but one that clinicians should understand. Although no disease-modifying treatment currently exists for alkaptonuria, the use of symptomatic treatments and, particularly, surgical decompression is recommended to address myelopathy if it develops. LEVEL OF EVIDENCE: 4.

Surgical Management for Destructive Atlantoaxial Spondyloarthropathy in Long-Term Hemodialysis Patients.

BACKGROUND: Atlantoaxial spondyloarthropathy most often results from rheumatoid arthritis, cancer metastasis, or basilar invagination. Dialysis-related spondyloarthropathy is a rare cause of spinal deformity and cervical myelopathy at the atlantoaxial joint. We report 2 patients on long-term hemodialysis who presented with atlantoaxial spondyloarthropathy. CASE DESCRIPTION: Two patients with end-stage renal failure presented with a history of progressively worsening neck pain, motion limitation, and gait disturbance. In both patients, radiologic findings showed a bone-destroying soft tissue mass lateral to C1 and C2, compressing the spinal cord and causing atlantoaxial instability. We performed a C1 laminectomy and C12 transarticular screw fixation and biopsied the osteolytic mass. The neck pain, hand numbness, and gait disturbance improved. CONCLUSIONS: Although the surgical management of these patients involves many challenges, appropriate decompression and fusion surgery is an effective treatment option.

Long-term follow up of surgical outcomes in patients with cervical disorders undergoing hemodialysis.

OBJECT: As increasing numbers of patients receive long-term hemodialysis, the number of reports regarding hemodialysis-related cervical spine disorders has also increased. However, there have been few reports summarizing the surgical results in patients with these disorders. The objective of this study was to evaluate the long-term follow up and clinical results after surgical treatment of cervical disorders in patients undergoing hemodialysis. METHODS: Seventeen patients in whom surgery was performed for cervical spine disorders while they received long-term hemodialysis therapy were enrolled in this study. Of these, 15 underwent follow-up review for more than 3 years after surgery, and these represent the study population. The remaining two patients died of postoperative sepsis. The average follow-up period was 120 months. Five patients without spinal instability underwent spinal cord decompression in which bilateral open-door laminoplasty was performed. Ten patients with destructive spondyloarthropathy (DSA) underwent reconstructive surgery involving pedicle screw (PS) fixation. In eight patients in whom posterior instrumentation was placed, anterior strut bone grafting was performed with autologous iliac bone to treat anterior-column destruction. Marked neurological recovery was obtained in all patients after the initial surgery. In the mobile segments adjacent to the site of previous spinal fusion, the authors observed progressive destructive changes with significant instability in four patients (40%) who underwent circumferential spinal fusion. No patients required a second surgery after laminoplasty for spinal canal stenosis without DSA changes. CONCLUSIONS: Cervical PS-assisted reconstruction provided an excellent fusion rate and good spinal alignment. During the long-term follow-up period, however, some cases required extension of the spinal fusion due to the destructive changes in the adjacent vertebral levels. Guidelines or recommendations to overcome these problems should be produced to further increase the survival rates of patients undergoing hemodialysis.

Challenges of cervical reconstruction for destructive spondyloarthropathy in renal osteodystrophy.

Patients with end stage renal disease on hemodialysis may present with destructive spondyloarthropathy of the spine, most commonly in the subaxial cervical and lumbar spine, often with severe stenosis and instability. However, surgical management of these patients is challenging due to a high pseudarthrosis rate, poor bone quality, and medical frailty. We present a 49-year-old man on hemodialysis who presented with C4-C5 vertebral body destruction and a focal kyphotic deformity with myelopathy. The patient underwent a 360 degree decompression and reconstructive procedure that resulted in posterior instrumentation failure. Several salvage techniques were used in order to adequately stabilize the spine while preserving the patient's remaining cervical motion.

[Expansive laminoplasty: an alternative for the treatment of cervical spondyloarthrosis]. / Laminoplastia expansiva: uma alternativa no tratamento da mielopatia espondilótica cervical.

We describe the surgical technique of expansive cervical laminoplasty and analyse the results in 28 patients treated by this method for cervical spondylotic myelopathy with a minimum follow-up of six months. Twenty-four patients (86%) had clinical improvement according to the Nurick scale while three (10%) had no improvement and one patient died on the first days post-operatively. The good results achieved demonstrate that this technique is simple, effective and has few complications on the treatment of spondylotic myelopathy.

Progressive symptomatic kyphotic deformity after decompressive surgery for lumbar destructive spondyloarthropathy.

Destructive spondyloarthropathy (DSA) is a serious complication of haemodialysis for end stage renal failure. We present a case of a patient who complained of back pain and cruralgia due to L2-3 disc degeneration with instability, and was treated with posterior decompression and bone grafting. Soon after surgery, the kyphotic deformity progressed and the symptoms deteriorated. A correction of the deformity and posterior fusion was required six years after initial surgery. Pathological findings showed characteristic findings of DSA. Our findings indicate that in some cases with unstable DSA, spinal decompression as well as spinal fixation may be necessary.

[Efficacy of arthrodesis in the posterior approach of cervical myelopathy: comparative study of a series of 36 cases]. / Eficacia de la artrodesis en el abordaje posterior de la mielopatía cervical: estudio comparativo de una serie de 36 casos.

OBJECTIVE: The effectiveness of arthrodesis associated to laminectomy as a treatment for cervical myelopathy has been retrospectively evaluated analysing the clinical evolution of 36 patients as well as the change in cervical column saggittal curvature comparing a group of patients with a simple laminectomy to another in whom laminectomy was accompanied by posterior arthrodesis. MATERIAL AND METHODS: 36 posterior approaches were performed to treat patients diagnosed of spondyloartrosic myelopathy between 1992 and 1999; 19 cases were treated with a simple laminectomy and other 17 also underwent arthrodesis with posterior instrumentation. The clinical evolution (using grades 0-5 on the Nurick scale) and cervical curvature have been evaluated for an average time interval of 40 months. RESULTS: Patients treated with laminectomy plus arthrodesis showed an average 1.24 point improvement on the Nurick scale in comparison to the 0.84 point improvement observed in patients treated with laminectomy alone. The cervical curvature attained a more physiological angulation in 53% of the patients with an arthrodesis and in 29% of the patients with simple laminectomy; curvature worsened in 7% of the patients with arthrodesis and in 24 degrees/a of those with laminectomy alone. CONCLUSION: Cervical myelopathy cases requiring a posterior approach for laminectomy obtain a better clinical evolution when an arthrodesis with posterior instrumentation is associated with the laminectomy. These patients also present improved cervical curvature as compared to the group without instrumentation.

Risk factors for intraoperative lateral mass fracture of lateral mass screw fixation in the subaxial cervical spine.

OBJECT: Although lateral mass screw fixation for the cervical spine is a safe technique, lateral mass fracture during screw fixation is occasionally encountered intraoperatively. This event is regarded as a minor complication; however, it poses difficulties in management that may affect fixation stability and clinical outcome. The purpose of this study is to determine the incidence and etiology of lateral mass fractures during cervical lateral mass screw fixation. METHODS: A retrospective clinical review of patient records was performed in 117 consecutive patients (mean age 57 years, range 15-86 years) who underwent lateral mass screw fixation using a modified Magerl method from 1997 to 2010 at a single institution. A total of 555 lateral masses were included in this study. The outer diameters of the screws were 3.5 or 4.0 mm. In the retrospective clinical analysis, the incidence of intraoperative lateral mass fractures was reviewed. Potential risk factors for this complication were assessed using multivariate analysis. RESULTS: The incidence of lateral mass fractures during cervical lateral mass screw fixation was 4.7% (26 lateral masses) among all cases. Among the disorders, the incidence was highest in patients with destructive spondyloarthropathy (DSA) (18.8%, 12 lateral masses). There was no significant difference with respect to lateral mass fracture between the use of 4.0-mm screws (5.6%) and 3.5-mm screws (3.6%). Independent risk factors identified by logistic regression were DSA (OR 7.89, p < 0.001) and screw insertion in the C-6 lateral masses (OR 2.80, p = 0.018). CONCLUSIONS: The overall incidence of lateral mass fracture during cervical lateral mass screw fixation was 4.7%. Destructive spondyloarthropathy as an underlying cause of morbidity and screw placement in the C-6 lateral mass were identified as independent risk factors. Use of a 4.0-mm screw in patients with DSA may be a principal risk factor for this complication.